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Tanzanian government, IITA to further joint efforts to develop cassava industry in the country


Tanzanian government, IITA to further joint efforts to develop cassava industry in the country

Cassava has and will always play a big role in improving the lives of farmers in Tanzania as it is widely grown in most parts of the country and holds immense potential as a cash crop through value addition. The government will therefore support efforts aimed at supporting farmers to optimize the crop and realize this potential, the Minister of Agriculture, Food Security and Cooperatives, Hon Engineer Christopher Chiza has said.

Hon Chiza noted that in Tanzania cassava still suffers from being widely perceived as a fall-back crop during famine while the prevalence of cassava mosaic and cassava brown streak diseases hamper  its production.  

The minister was speaking to a delegation from the International Institute of Tropical Agriculture (IITA) led by Dr Victor Manyong, Director for Eastern Africa, during a courtesy call to the minister’s office this week.

The minister also noted that although a lot of cassava is being grown in different parts of the country and some even exported to neighboring countries, a good volume of the crop is still wasted and rotting in many farmers’ fields. He therefore urged IITA to continue assisting the country’s farmers to optimally produce and use this crop through its research efforts, and in return he assured the team of his ministry’s full support.

He said the country  needed research on processing and on marketing, and the findings to be widely disseminated to reach farmers. He added that farmers also need access to varieties that can withstand the two main cassava diseases.

Dr Manyong, on his part, said Tanzania is one of IITA’s priority countries and that the institute is investing a lot of resources to boost its research and development capabilities and activities in the country.

He emphasized that it is due to the good support received from the government that IITA decided to establish its Eastern Africa Hub in Dar es Salaam, Tanzania. He added that IITA is currently constructing a state-of-the-art science building at its offices in Mikocheni to backstop its research activities in the country. He reported that the science facility will be completed early next year.

Dr Manyong also assured the honourable minister  that IITA will bring to fore its abundant technical expertise to support the Tanzanian government in enhancing the country’s agricultural sector, especially focusing its efforts towards cassava commercialization.

Dr Kanju, IITA Cassava Breeder who was also with the visiting delegation, told the minister that the institute, together with relevant government departments and development partners in the country,  had achieved significant successes in developing cassava varieties that were tolerant to the two diseases. He added that some of these varieties have already been officially released to farmers.  He noted, however, that the challenge now is producing enough planting materials to address the demands of farmers. To this end, he said that IITA and its partners are undertaking planting material multiplication efforts.

The minister assured the IITA team that in order to help with the multiplication efforts, his office will explore the possibility of tapping into institutions such as prisons and the National Youth Service (NYS).

For more information, please contact:
Catherine Njuguna ( This e-mail address is being protected from spambots. You need JavaScript enabled to view it )
IITA East Africa Hub
Dar es Salaam, Tanzania

Dear Hoang Kim,     
Below, please find a press release that may be of interest to your blog.
Warm regards,
For immediate release
08  September 2012

About IITA

Africa has complex problems that plague agriculture and people's lives. We develop agricultural solutions with our partners to tackle hunger and poverty. Our award-winning research for development (R4D) is based on focused, authoritative thinking anchored on the development needs of sub-Saharan Africa. We work with partners in Africa and beyond to reduce producer and consumer risks, enhance crop quality and productivity, and generate wealth from agriculture. IITA is an international nonprofit R4D organization established in 1967, governed by a Board of Trustees, and is a CGIAR Research Center.

Lessons from Vietnam (Trip report of Mr. Boma)

“Vietnam is a classic example of how cassava can contribute to rural industrialization and development. Previously, people were reluctant to grow cassava because they thought that cassava caused soil degradation and produced low profits. But in reality one hectare of cassava can produce 60-80 tones of fresh roots and leaves. The situation has changed because of the development of sustainable cultivation techniques and new high-yielding varieties with the availability of a large and growing market demand. Cassava has become a cash crop in many provinces of Vietnam. Cassava chips and starch is now being produced competitively, and cassava markets are promising. The combination of wide spread production of fresh cassava roots and the processing of cassava into chips starch and ethanol has created many jobs, has increased exports, attracted foreign investment, and contributed to industrialization and modernization of several rural areas”.


CROPS FOR BIOFUEL to follow up 234NEXT.COM. By Ayodamola Owoseye December 20, 2009. With the whole world clamouring for reduction in the burning of carbon in order to slow down the effects of global warming, Nigeria may soon be able to reduce its carbon emission by using ethanol fuel as substitute for kerosene. (Picture: Dwindling cassava cultivation inhibits the planned conversion of cassava to ethanol for energy production)

More ...

Boma Anga, the chief executive officer of Cassava Agro Industries Service Ltd (CAISL) said in a telephone interview that Nigerians will soon be able to use ethanol across the country as an option for household cooking fuel.

"Nigerians will be able to purchase ethanol fuel for cooking by March 2010," said Mr. Anga. "The cooking fuel also known as Cassakero (cassava-kerosene) will be available to the public as an alternative to kerosene in order to reduce the money spent on fuel usage by most families," Mr. Anga added.

Ethanol as substitute

The idea of looking for a substitute for the carbonised cooking fuel (kerosene) and wood came as a result of the harmful impact on the environment and climate change.

Since carbon burning has been identified as one of the reasons for climate change, the world decided to look for alternative means in terms of biofuel, which is renewable fuel derived from biological matter, for instance biodiesel, biogas, and methane which are all believed to have less hazardous impact on the ecosystem.

Mr. Anga said the Cassakero initiative was planned as substitute for kerosene and wood for Nigerians through the production of ethanol from cassava root.

"This is to promote the use of ethanol as a substitute for kerosene in the country as this will reduce the greenhouse effect caused by the use of carbon fuel. The programme is targeted toward installing about 10,000 small-scale bio ethanol refineries in the 36 states of the federation, including the FCT, over the next four years, to produce daily ethanol cooking fuel requirement for four million families," he said.

Food security

But the project is raising concerns about food security as cassava is a major staple of most Nigerians. It is used in producing flour which is made into a paste and the popular garri, eaten in most homes across the land.

Mr. Anga, however, said the project will not have any negative effect on cassava supply in the market nor will it affect food security as the companies will be using specially cultivated, industrial cassava.

"Considering the tonnes of cassava required for the project, I want to assure you that it will not endanger food security as we will be using non-edible industrial variety of cassava which will be planted on fresh land.

"We have already established a feedstock supply that will produce eight million tonnes of cassava at an average yield of 25 tonnes per hectares from 320,000 hectares to be planted nationwide. To also ensure a steady supply of cassava for the feedstock, we have signed a contract with Nigerian Cassava Growers Association (NCGA) to supply eight million tonnes of cassava tubers," he added.

He said the contract would benefit over 250,000 cassava farmers across the country with additional 400,000 hectares to be deployed for cassava cultivation as the refinery will require 40 hectares of cassava to supply 100 per cent feedstock requirement annually.

Cassava farmers welcome the initiative

Cassava farmers see this as a welcome initiative, as it will increase the market for the produce and encourage more people to embark on farming.

Jimoh Bashir, a cassava farmer, said the initiative is a good one as this will allow more farmers to cultivate the crop more, knowing that there is a market for it as compared to when farmers had to seek for buyers to buy the commodity from them.

"This is a nice initiative that we hope will last long as it will open up the market," Mr. Bashir said.

"Most of what is produced in the country is used in the food sector. Having the product used in the industries will only enhance our financial status as this means there will be more produce with a ready market. This means most of the farmers that have abandoned farming will be lured back to it," he said.

Mr. Bashir is, however, concerned about the affect of this on food production in the country as there is a tendency for farmers to change from producing edible cassava for the industrialised ones.

"This might, however, pose a threat to the production of edible cassava by farmers. Farmers will tend to concentrate more on producing the industrial cassava root with a ready market and use, than cultivating the normal ones. This might also affect the market price of the crop," he said.

Economic implications for Nigerians

With the federal government's plan to deregulate the downstream oil sector which might lead to a sharp increase in the prices of petroleum products, especially kerosene, the domestic cooking fuel for most households, the average Nigerian will have to spend more on the purchase of the product or seek alternative means such as coal or wood which will further endanger the environment.

Mr. Anga arued that ethanol will be cheaper and available for the masses as it burns slower than the normal kerosene fuel.

"The new fuel will be locally produced; and provide Nigerians with a new household fuel for use in cooking, lighting, heating, refrigeration and electricity generation. This fuel will be cleaner, safer and cheaper than kerosene without the need for government subsidy and the introductory price will be retailed at about N75 per litre," he said.

"The production and the distribution of the ethanol based appliances will create employment and wealth to investors and the nation in general. The programme will also create sustainable employment and reduce poverty and deforestation while enhancing food and energy security in the Nation.

"The primary goal is to make ethanol as a cooking fuel available, accessible and affordable, in a commercially profitable and sustainable manner, to low income Nigerians," he added.



ICES Biofuels Project

FOODCROPS. Dự án nhiên liệu sinh học của ICES.



What 's in the news of biofuel 12.2009

CROPS FOR BIOFUEL to follow up Peter Baker 2010 in Biofuel Information Exchange:  A new major report on biofuels by UNEP1 helps us do this by usefully summarizing the current global biofuels situation. Biofuels now account for 1.8% of transport fuels with ethanol production having tripled between 2000 and 2007 and biodiesel production rising eleven-fold. Mandates to blend biofuel into fossil fuels for vehicles had been enacted in 17 countries by 2006, mostly requiring blending with 10 to 15% ethanol or 2 to 5% biodiesel. In short, biofuels has become a major business with all the momentum that such a new commercial endeavour can create. Thus Brazil exported 5 bn L of ethanol in 2008 and investment in biofuels rose to US$4 bn in 2007 and has most likely risen substantially since then. So much for recent history: when we come to the future however, projections vary wildly, from a pessimistic energy provision of 40 EJ/annum2 to 200 to 400 EJ per annum or even higher by 2050. This compares to current fossil fuel energy use of 388 EJ/annum. The report considers that the most realistic range is 40 to 85 EJ/annum by 2050. Shorter term projections expect biomass and waste to contribute 56 EJ/annum by 2015 and 68EJ/annum by 2030. Most of this increase is expected to come in USA, EU, Brazil and China.

CROPSFORBIOFUEL vừa cập nhật tin của Peter Baker 2010 trong Trao đổi Thông tin Nhiên liệu Sinh học (BIOFUEL INFORMATION EXCHANGE): Một báo cáo mới đây về nhiên liệu sinh học của UNEP 2009 đã giúp chúng ta tài liệu quý giá tổng kết tình hình nhiên liệu sinh học toàn cầu hiện nay. Năm 2007, nhiên liệu sinh học chiếm 1,8% nhiên liệu giao thông với sản lượng ethanol tăng gấp ba lần so với năm 2000 và sản xuất dầu diesel sinh học tăng lên mười lần. Nhiệm vụ  pha trộn nhiên liệu sinh học vào nhiên liệu hóa thạch cho xe đã được ban hành tại 17 nước vào năm 2006, chủ yếu là đòi hỏi phải pha trộn 10-15% ethanol hoặc 2-5% dầu diesel sinh học vào xăng. Nhiên liệu sinh học những năm gần đây đã trở thành một thị trường rộng lớn với một nỗ lực thương mại mới đang hình thành. Năm 2008, Brazil đã xuất khẩu 5 tỷ lít ethanol và đầu tư vào nhiên liệu sinh học đã tăng lên 4 tỷ đô la Mỹ so với năm 2007. Thị trường thương mại nhiên liệu sinh học đang tăng mạnh ở Mỹ EU, Brazil và Trung Quốc.
The end of the biofuel decade
A major agricultural phenomenon of the first decade of the 21st century has been the rise of biofuels, and as it draws to a close, it’s a useful time to take stock.
A new major report on biofuels by UNEP1 helps us do this by usefully summarizing the current global biofuels situation. Biofuels now account for 1.8% of transport fuels with ethanol production having tripled between 2000 and 2007 and biodiesel production rising eleven-fold. Mandates to blend biofuel into fossil fuels for vehicles had been enacted in 17 countries by 2006, mostly requiring blending with 10 to 15% ethanol or 2 to 5% biodiesel. In short, biofuels has become a major business with all the momentum that such a new commercial endeavour can create. Thus Brazil exported 5 bn L of ethanol in 2008 and investment in biofuels rose to US$4 bn in 2007 and has most likely risen substantially since then. So much for recent history: when we come to the future however, projections vary wildly, from a pessimistic energy provision of 40 EJ/annum2 to 200 to 400 EJ per annum or even higher by 2050. This compares to current fossil fuel energy use of 388 EJ/annum. The report considers that the most realistic range is 40 to 85 EJ/annum by 2050. Shorter term projections expect biomass and waste to contribute 56 EJ/annum by 2015 and 68EJ/annum by 2030. Most of this increase is expected to come in USA, EU, Brazil and China.
The report makes the important point that in making future projections there are major uncertainties regarding the demand for land for agriculture, especially considering expected low growth in crop yields, expanding populations as well as yield and land degradation due to climate change.
These uncertainties extend to Life Cycle Assessments (LCA), which, depending on the study, show wide variations in efficiencies. The highest variations are observed for biodiesel from palm oil and soya. The highest greenhouse gas saving come from biogas derived from manure and ethanol derived from agricultural and forest residues, as well as biodiesel from wood; though this latter is based only on experimental plants. And, despite many studies, the UNEP report finds them lacking in assessment of indirect effects, including eutrophication, acidification, human and eco-toxicity potential or ozone depletion. Significant variation in LCAs result from nitrous oxide emissions, which are a particularly strong GHG –many of the LCA studies have used rather low values from the Intergovernmental Panel on Climate Change, but if the higher levels suggested by Crutzen et al.3 are corroborated, the LCA studies will have to be recalculated. Tellingly too says UNEP, none of the LCA studies look at biodiversity effects.
Estimates of land required for biofuels, to meet current country mandates, vary widely. These depend on basic assumptions – the feedstock, geographical location and levels of input and yield increases expected. The range of estimates is staggeringly broad, from 35 to 166 million ha by 2020, which is a conservative range, assuming no new biofuels policies are promoted. It is calculated that somewhere between 118 to 508 million ha would be required to provide 10% of global transport fuel demand.
However, by 2020 somewhere between 144 and 334 million ha of extra land is needed for food, so there is currently no convincing strategy or even concept of where biofuels will be grown. Some indication of where things might be heading can be found in a new article by Tom Simpson4. He points to the many deficiencies of corn based ethanol and seriously questions its viability on environmental and economic grounds.
Simpson believes that the future for US biofuels at least is more likely in perennial biomass crops, like switchgrass or fast-growing hardwoods, which lose 75 to 90 percent less Nitrogen to water, reduce greenhouse gas emissions, provide habitat, and can be used to replace crude oil without conversion to ethanol.
In another recent paper, Jerry Melillo5, with his colleagues of the Woods Hole Marine Biological Laboratory in the US, has modeled how growth in biofuel production will change world agriculture during the 21st century. They concentrate on the most likely future— which like Simpson, they believe is cellulosic biofuels from whole plants such as fast-growing grasses, rather than today’s biofuel crops mostly derived from food plants. Surprisingly perhaps, they believe that Africa is the best place to grow biofuels, and the one that will lead to most carbon capture in the long run. But their model also shows that expansion of biofuel crops is likely to cause a net global release of greenhouse gases during the first half of the century, as land is cleared and fertilized. In the right circumstances the CO2 account, they find, could move into profit by mid-century, but the nitrous oxide account never does. The problem with this of course is that with accelerating climate change, there is an urgent need to reduce emissions over the next 20 years, so it is very questionable whether it is justifiable to allow the carbon account of biofuels to enter what looks like a prolonged period of deficit.
Corroboration for this comes from a new paper by Vuichard et al.6, which through modeling shows a carbon deficit of at least 25 years for any implementation of a grassy biofuel production strategy on the 20 million ha of abandoned Soviet agricultural lands, compared to their current state of inactivity. An interesting new angle on the enigma that is Jatropha comes in a recent paper by Maes et al.7 who set out to define the climatic conditions in its area of natural distribution by combining the locations of herbarium specimens with corresponding climatic information. Most specimens (87%) were found in tropical savannah and monsoon climates and in temperate climates without dry season and with hot summer, while very few were found in semi-arid and none in arid climates. Surprisingly, more than 95% of the specimens grew in areas with a mean annual rainfall above 944 mm per year and an average minimum temperature of the coldest month (Tmin) above 10.5°C. The mean annual temperature range was 19.3-27.2°C.
However, when they compared these conditions with those in 83 Jatropha plantations worldwide, they found a very different story. Roughly 40% of the plantations were situated in regions with a drier climate than in 95% of the area of the herbarium specimens, and 28% of the plantations were situated in areas with a Tmin below 10.5°C. They suggest therefore that many plantations are sub-optimally located, holding the risk of chronic low productivity or cold damage.
Another Jatropha paper by Kheira and Atta8 studied its suitability under Egypt's climate in unused lands under scarce water conditions. The results revealed that the average water consumption rate of the Jatropha bush was 6 L per week throughout the growing season, which means that Jatropha can survive and produce full yield with high quality seeds under minimum water requirements compared to other crops. The yield of extracted oil however was extremely low, achieving only 58 kg oil yield per ha at an optimal 100% of potential evapotranspiration.
The sheer complexity of biofuels is brought out well by a recent exchange of letters in the December 4th edition of Science9: various scientists well-known in the biofuels sector comment on a previous article by Tilman et al.10 that argued that the search for beneficial biofuels should focus on feedstocks that (i) do not compete with food crops, (ii) do not lead to land-clearing, and (iii) offer real greenhouse-gas reductions. The various letter writers suggested additional criteria:
v) Rist et al.: the maximization of social benefits, for example the negative impacts of oil palm development such as poor wages and labour standards, impacts on health and local culture, “land grabbing,” and the loss of environmental goods and services.
v) Biksey & Wu: environmental and health impacts of the co-products that arise during generation of biofuels from feedstocks. For example, maize-based ethanol production results in the production of by-products sold as animal feed. It has been found that any mycotoxins in the original maize become up to three times as concentrated in these co-products and production of biofuels from waste materials may release chemicals such as dioxins and heavy metals that could result in unintended environmental and public health exposures.
vi) Duffy et al.: algae were overlooked by Tilman et al. as a solution. They claim that about 30 million ha of algal culture would yield more than 100% of the US petroleum diesel usage, even assuming modest algal productivity. They consider that microalgae are typically at least an order of magnitude more productive than even the fastest growing terrestrial feedstock crops. However, as we reported in the October 2009 addition of 'What's in the News', not all scientists agree with this optimistic assessment of the efficiency of algae.
vii) Kauppi & Saikku: the neglected role of forests and carbon capture and storage. Trees offer promise as an energy crop in areas where they grow well on degraded lands. A new and permanent reservoir of carbon is created as planted forest develops toward a steady state where mature trees mix with young saplings. Forests also offer a great variety of ecosystem services such as biodiversity promotion, nutrient retention, and flood protection. Timber crops can be harvested at any time during the year, and the durable wood serves as an interim energy storage—two assets for energy transport logistics. The carbon budget of wood is competitive against other materials in end uses such as construction.
Opportunities to use side-products from wood-processing industries in electricity production should be fully explored. As Simpson above also suggests, biopower by almost any criterion deserves attention. Greenhouse gas benefits are better achieved making electricity than fuels.
viii) Lal & Pimentel: the dangers of using crop residues and harvesting biomass from double crops and mixed cropping systems. Retention of crop residues on soils, including the biomass produced from cover crops, is essential to numerous ecosystem services such as carbon sequestration, conservation of soil and water, and high use-efficiency of inputs for increasing and sustaining agronomic productivity. They point out that the almost perpetual food deficit in sub-Saharan Africa is attributed to severe soil degradation caused by extractive farming practices. These involve continuous removal of crop residues for use as traditional biofuels and cattle feed that has created a negative nutrient budget. Soils are a source of greenhouse gases when prone to accelerated erosion and when under management that creates negative carbon and nutrient budgets. Furthermore, crop residues and other biosolids are essential to maintain activity and species diversity of soil biota (micro and macroorganisms) and to improve soil structure and tilth. Lal and Pimental urge that the indiscriminate removal of crop residues and harvesting of biomass from cropland soils is supported neither by science nor by conventional wisdom.
x) Spangenberg & Settele: the downside of growing perennials on degraded lands that can no longer be used for agriculture. Land fertile enough to grow plants offering substantial yields for biofuels, should be suitable for agriculture as well. Even if not used today, this land could be kept as a productive reserve and used later to combat the foreseeable problems in feeding the world in the future. If the land is not fertile enough for that purpose, the perennial energy plants will probably be dependent on anthropogenic inputs such as fertilizers and, in some regions, irrigation. These are the factors disrupting the energy balance; nitrogen fertilization is the basis for nitrous oxide emissions with the potential to overcompensate all greenhouse gas gains. Economically, such plantations would not be viable without intensive farming practices, raising doubts regarding the expected benefits for biodiversity and wildlife.
Currently only about 10% of the global primary energy demand is covered by renewable resources, and humans already appropriate large percentages of the potentially available biomass (20 to 40% globally, 50% in some industrialized countries, up to 90% in intensively farmed regions). Hence, Spangenberg and Settele are sceptical about the potential of biofuels and they cannot support the demand that “a robust biofuels industry should be enabled now.”
The authors of this final letter end by suggesting to ‘better look before we leap’, which is a fitting epitaph on the ‘noughties’ (2000-2009) – when so many catastrophic political and economic decisions were made on flimsy evidence or a dogmatic, one-sided view of life. Let us hope that the future of biofuels can be placed on firmer ground by thoroughly modelling and researching their true potential to reveal all the complexity and long term ramifications that we are now just beginning to comprehend.
By Peter Baker
Assessing Biofuels, UNEP 2009
EJ = exajoules = 1018 joules
Crutzen PJ, Mosier AR, Smith KA Winiwarter W, 2007. N2O release from agro-biofuel production negates global warming reduction by replacing fossil fuels. Atmos. Chem.
Phys. Discuss., 7: 11191–11205
Simpson T, 2009. Biofuels: The Past, Present, and a New Vision for the Future. BioScience Vol. 59 No. 11: 926-927
Melillo JM, Reilly JM, Kicklighter DW, Gurgel AC, Cronin TW, Paltsev S, Felzer BS, Wang X, Sokolov AP, Schlosser CA, 2009. Indirect Emissions from Biofuels: How Important? Science, 326: 1397 - 1399
Vuichard N, Ciais P, Wolf A, 2009. Soil Carbon Sequestration or Biofuel Production: New Land-Use Opportunities for Mitigating Climate over Abandoned Soviet Farmlands. Environ. Sci. Technol., 43: 8678–8683
Maes WH, Trabucco A, Achten WMJ, Muys B, 2009. Climatic growing conditions of Jatropha curcas L. Biomass and Bioenergy, Vol. 33 No. 10: 1481-1485
Kheira, A, Atta N 2009, Response of Jatropha curcas L. to water deficits: yield, water use efficiency and oilseed characteristics. Biomass and Bioenergy, 33: 1343-1350
Science Letters, Vol 326: 1345-46.
Tilman D, Socolow R, Foley J, Hill J, Larson E, Lynd L, Pacala S, Reilly J, Searchinger T, Somerville C, Williams R, 2009. Beneficial Biofuels — The Food, Energy, and Environment Trilemma. Science, 325: 270 - 271
Current situation of cassava in Vietnam and the breeding of improved cultivars

China's first bioenergy research center inaugurated in Nanning

CROPS FOR BIOFUEL to follow up CHINA DAILY June 16 2009. China's first bioenergy research center was inaugurated Sunday in Nanning, the capital city of southern Guangxi Zhuang autonomous region, amid government's plans of new energy development to combat global energy crisis. The research center is set up based on the national guidance on energy and grain security, and will look to cassava, sugar cane, sweet sorghum as the main sources for new energy development.



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Bioenergy has good prospects in tackling energy crisis and protecting grain security and ecological environment since it has low emission and in contest with human beings for resources, said Huang Ribo, director of the research center.

China has abundant bioenergy resources, which is expected to total five billion tons. The tropical Guangxi has rich reserve of cassava, sugar cane, which takes up more than 65 percent of the nation's total, he said.

China's first cassava-for-alcohol fuel project, which has an annual capacity of 200,000 tons, was started in Beihai city of Guangxi in 2007.

The Guangxi Academy of Sciences will support the research center with research talents and facilities.

According to a report released by the Chinese Academy of Sciences on June 10, bioenergy is expected to realize commercial production on a massive scale in China and replace 30 percent of the oil imports by 2050.


By Hao Zhou (

Updated: 2008-04-24 17:10 Comments(0) PrintMailChina will strictly control bioenergy development at the cost of grain and oil crop shortage, declared Agriculture Minister Sun Zhengcai, on April 21 in a talk with the Danish Minister for Food, Agriculture and Fisheries Eva Kjer Hansen, in China on a visit.

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As crude oil prices have continuously broken new highs in reaching the current level of $110 per barrel, developing bioenergies is heating up around the world. Some 40.5 million tons of fuel ethanol and 5.4 million tons of bio-diesel were produced worldwide in 2006, increasing two and three fold respectively from the figures in 2001.

However, around 12 percent of corn in the world and 20 percent in the United States is used for producing fuel ethanol, and 20 percent of rap oil in the world and 65 percent in the European Union, as well as 30 percent of Southeast Asia’s palm oil is used for producing bio-diesel, and has contributed the current global grain and edible oil prices.

Both the Organization for Economic Cooperation and Development and International Monetary Fund have expressed their concerns that roaring demand for biofuels would pressure farm produce prices globally in the long-run.

In this case, China should mainly utilize agricultural wastes, such as wheat straws and corn stalks, animal feces, as well as rotten leaves, and non-grain farm produces, like cassava, sweet potato, sweet sorghum, sugar beet, and jerusalem artichoke, as its own approach to develop bioenergies, rather than at the expense of grains that already short in supply, said Sun.

China has about 100 million hectares of mountains, shoals, and saline or alkaline lands which are not suitable for growing grains but energy plants.

Sun said roughly 26 million Chinese families in rural areas had started making use of self-produced methane last year, and five million more are expected to join in this year.

According to the Renewable Energy Development Plan for the 11th Five-Year period released last month by the National Development and Reform Commission, by the year of 2010 renewable energies will account for 10 percent of the national energy consumption structure, and electricity generated by biological materials will reach an installed capacity of 5.5 million kW.

Meanwhile, some 2.2 million tons more of fuel ethanol produced by non-grain materials are set forth for the 11th Five-Year period, and annual bio-diesel consumption will reach 200 thousand tons by 2010.


By Li Huayu (

Updated: 2008-01-09 11:47

The US new-energy firm General Biodiesel plans to launch four projects in Beijing, Shanghai, Guangzhou, and Wenzhou of East China's Zhejiang Province, said company CEO Yale W. Wong in Beijing yesterday.

Currently on visit to China, Wong said that the planned initial investment for the four projects is about $500,000, and after a year the company will increase its total investment to $100 million.

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With an office in Beijing, the Seattle-based company specializes in producing high-quality biodiesel by processing vegetable oils - primarily palm, canola, soy, linseed, coconut, mustard and cotton - and by cleaning and recycling cooking oils.

As energy saving and environmental protection in China are increasingly pressing issues, the country has launched a slew of policies to encourage the development of new energies. For instance, the Chinese government has set the target of increasing biodiesel output to 200,000 tons by 2010 and two million tons by 2020.

Eyeing the huge potential, General Biodiesel is also seeking a joint-venture partnership in China. Wong said that the company has picked some potential partners, and is expected to ink a deal during this visit.

One of the potential partners is in the aviation sector, disclosed Wong, without revealing the company's name. He said his company is testing feasibility of using biodiesel products as jet engine lubricants or jet fuel.

Being a member of a clean-energy trade mission headed by US Assistant Secretary of Commerce David Bohigian and scheduled to visit China and then India, Wong said he would fly back to the United States after the China leg. "China is enough for us," he said.

Biodiesel is the natural equivalent to diesel. Diesel comes from petroleum, a nonrenewable resource, while biodiesel comes from organic, and all renewable, sources –such as soybean or rapeseed oils, animal fats, waste vegetable oils, or microalgae oils.

Wong said with the process from his company, biodiesel production will consume 99 percent of waste oils and no water at all. One of its by-products is glycerin, which can be made into fertilizers or distilled to 99 percent purity or higher and sold for cosmetic and pharmaceutical markets use.

Cassava variety KM140

FOODCROPS. KM140 is a short growth duration variety (best harvesting time 7-9 months after planting) with fresh root yield 33.4 ton/ ha (higher than KM94), starch content 27% and starch yield about 9.5 ton/ha for 7-9 months after planting, HCN content about 105.9 mg/kg of root dry matter, good root shape with white flesh, high adaptability to various production conditions. KM140 is a supplementary variety for main variety KM94 in order to extend harvesting time.



Tran Cong Khanh1, Hoang Kim2, Vo Van Tuan1, Nguyen Huu Hy1,

Dao Huy Chien3, Pham Van Bien1, Reinhardt Howeler4 and Hernan Ceballos4

1. Institute of Agricultural Sciences for Southern Vietnam (IAS), 121 Nguyen Binh Khiem St., Ho Chi Minh city, Vietnam (website: ;  )

2.  Nong Lam University; Linh Trung Ward, Thu Duc District, Ho Chi Minh City, ;   

3.   Vietnamese Academy of Agricultural Sciences (VAAS) Van Dien, Thanh Tri, Ha Noi, Viet Nam

4. International Center for Tropical Agriculture (CIAT), Cali, Colombia; This e-mail address is being protected from spambots. You need JavaScript enabled to view it ; CIAT c/o FCRI, Dept. of Agriculture, Chatuchak, Bangkok, 10900 Thailand This e-mail address is being protected from spambots. You need JavaScript enabled to view it  


In Vietnam, cassava has rapidly changed its role from a food crop to industrials crop, with a high rate of growth during the first years of the 21 st Century. There are now 60 cassava processing factories in operation with a total processing capacity of 3.2-4.8 million tones of fresh roots/year. Total cassava starch production in Vietnam was about 800,000 -1,200,000 tonnes, of which 70% was exported and 30% used domestically. The main objectives of cassava breeding in Vietnam is improve root yield and starch content and enhance early harvestability to spread the time of harvest. Cassava variety KM140 is a hybrid selected from KM98-1 x KM 36 cross by Hung Loc Agricultural Research Center (HARC) in 1998. KM140 was widely tested, demonstrated and selected by most members of Viet Nam Cassava Research and Extension Network (VNCP) and cassava growers. In 2006, more than 10,000 ha of KM140 were planted in Dong Nai, Tay Ninh, Binh Phuoc, Binh Duong, DakLak, Kon Tum, Binh Dinh, Quang Ngai, Thua Thien- Hue, Quang Binh, Nghe An, Thanh Hoa, Yen Bai and Lao Cai. KM140 is a short growth duration variety (best harvesting time 7-9 months after planting) with fresh root yield 33.4 ton/ ha (higher than KM94), starch content 27% and starch yield about 9.5 ton/ha for 7-9 months after planting, HCN content about 105.9 mg/kg of root dry matter, good root shape with white flesh, high adaptability to various production conditions. KM140 is a supplementary variety for main variety KM94 in order to extend harvesting time.

Key words: cassava breeding; KM140 cassava variety.


We have caried out the study on the development of cassava cultivar with good yield and qualities for different ecological zones in South Vietnam, in collaboration with Root Crop Center- Institute of Agricultural Science and Technology of Vietnam. The objectives of this study were to breed and develop new cassava cultivars with growth duration from 7-10 months (1-2 months earlier as compared to cultivar KM94) with the same starch yield. New cultivars must have good appearance in root tube, white flesh, less bitterness, straight plant, shot nodes, small plant diameter, resistant to pests and diseases.


Currently, the cassava breeding program in Vietnam is evaluating about 123,566 hybrid seeds introduced from CIAT/Colombia, and is producing itself more than 48,848 hybrid seeds from 9-15 cross combinations. At Hung Loc Agricultural Research Center there are ten cassava breeding experiments conducted every year, and 18-24 regional trials are conducted in different cassava producing regions in collaboration with various institutions, universities and provincial extension offices. Cassava variety KM140 is a hybrid selected from KM98-1 x KM 36 cross in 1998.

Thirty cassava comparison experiments and two experiments for determining the best harvesting time of some cassava cultivars were carried out. On red soil, experiments were planted at beginning of rainy season and harvested after planting from 6,7,8,9,10,11 and 12 months. On grey soil, planted at beginning rainy season and harvested after 10,11 and 12 months.


Cassava cultivar comparison (1998-2005)

Data of 30 cassava comparison experiments from 1998 to 2005 revealed that KM140 has fresh root yield of 33.4 ton/ha, starch yield of 9.5 ton/ha; better than that of KM94. Content of HCN in KM140 is 105.9 mg/kg dry matter, it can be used as fresh consumption, lower than that of KM94; its harvest index was 65%, good resistance to pests and diseases.

KM140 is now playing an important role in cassava production in South East and Central Coastal regions, Central Highlands and the mountainous areas in the North (Quang Binh, Nghe An, Thanh Hoa, Yen Bai, Lao Cai). KM94 has been recognized by CIAT as one of the best cultivars in Asia (CIAT Review, 2005).

Determination of optimal harvesting time

Planting at middle of rainy season and harvesting 10 months later revealed that all cassava cultivars gave low starch content (16.6%-22.5%). If harvested 11 months after planting , almost cultivars had starch content around 25% satisfying the requirement of processors. If harvested 12 months after planting most of the cultivars gave good fresh root yield and starch content, but this would cause inconveniences for next crop cultivation. Considering above results and reason, it is recommended that the best harvesting time is 11 months after planting.

Planting at beginning rainy season and harvesting at 7,8 and 9 months after, KM140 gave fresh root yields of 23.5, 26.7 and 28.7 ton/ha, respectively, equal to that of KM94. Starch content of KM140 harvested 8 months after planting was 28.4% higher than that of KM94 (26.2%), with signnificant difference.


After 7 years (1998-2005) of breeding and selection at HungLoc Agricultural Research Center and testing- demonstrations over provinces, the prominent cultivar KM 140 has appeared to satisfy the objectives of study:

- Best harvesting time must be between 7 to 9 months after planting at beginning rainy season in South Eastern region of Vietnam.

- Fresh root yield of 33.4 ton/ha, starch content of 26.1 -28.5%; Starch yield of 9,45 ton/ ha.

- HCN content in KM140 root flesh is 105.9 mg/kg of dry matter.

- Erective and short inter-node plants, non branching in South Eastern region, low branching in Western Highland Plateau and in the Northern provinces.

- Uniform root shape, white root flesh which are satisfying the market preference and processing requirements.

- Resistance to pests and diseases


Sự phát triển gần đây của thế giới về nhiên liệu sinh học: Hè 2010

CROPS FOR BIOFUEL . Trang tin Chuyên gia Nhiên liệu Sinh học của CABI đã điểm tin "Sự phát triển gần đây của thế giới về nhiên liệu sinh học: Hè 2010". Nội dung chính đề cập đến phương pháp đánh giá toàn diện các dự án nghiên cứu và phát triển nhiên liệu sinh học theo Tổ chức tiêu chuẩn quốc tế (ISO). Có ít nhất 67 bản đánh giá chu kỳ dự án nhiên liêu sinh học đã được phân tích, xem xét. Những báo cáo mới về tình hình trồng cây dầu mè (Jatropha) ở Brazin và Trung Mỹ, virus khảm của cây dầu mè và ô nhiễm vi sinh vật của nhiên liệu sinh học.



How functional are life-cycle assessments (LCA)?

A recent review of no less than 67 biofuel life-cycle assessments (LCAs) was published recently in a new biofuel journal1. As Ester van der Voet and her colleagues point out, the very fact that politically determined biofuel targets have been set, has led to a major effort to show whether they might actually have a desirable effect for society. The review tries to find out what can be concluded from the studies and why and how they may differ.

And differ they most certainly do: in the first place the studies do not adopt the same functional units. Some express results in terms of amount of energy contained in the fuel, others the weight of the fuel or the yield per unit area (e.g. hectare) or even a composite measure. Such differences make comparison between studies difficult and lead to major differences between them. Different allocation methods, all approved under the International Organization for Standardization (ISO) standard for LCA studies, can cause percentage improvement compared with fossil fuels to vary from negative to above 100%.

The authors point out that the system boundaries vary between studies, which reflect their different purposes. Hence some are well-to-wheel, others are well-to-tank, cradle-to-gate (where ‘gate’ means the final product less costs of delivery to the tank) and even cradle-to-grave where the whole transport system is evaluated, including the car and the road. The latter is the most complete and indeed is surely needed if society is to evaluate the full costs of our current free-wheeling life styles. But by so doing, these most comprehensive studies tend to reduce the overall differences between the biofuel feedstock involved, which is often the centre of interest.

At the heart of this is a fundamental problem: LCAs were never designed to cover wide-ranging questions of such global concern. LCAs are, by concept, a way of determining costs and impacts of a particular process. They are especially useful for firms looking to reduce costs of energy and materials for a particular supply chain, or of reducing environmental pollution; Coca-Cola and Mobil Oil were early adopters. It is easy for a company to use LCAs, because they can be reduced to a bottom line expressed in terms of money saved.

But when we come to biofuels, the whole point of which is to be an overall benefit to humanity, the boundaries become global and the uncertainties proliferate. This is covered in some detail in a new book by Giampietro & Mayumi2, who point out that when dealing with living systems, one can easily get caught in an analytical loop in which everything depends on everything else. E.g. several options may be considered to calculate the required energy input for generating the supply of energy carriers (‘energy carriers’ are gasoline, biofuel and wind power for example):

Option A: include only the energy spent on the operation by the machines used in the energy sector;

Option B: Option A plus the energy used to fabricate and maintain the machines used in the energy sector;
Option C: A+B plus the energy used to reproduce the energy sector as a whole. This requires including the infrastructure and demand of services of the energy sector;
Option D: A+B+C plus the energy used to reproduce the humans working in the energy sector. Includes the leisure time, education & assistance to their families.

It’s easy to see that for an investor in a short term project, s/he might only be interested in A and B. For a long term investor option C would be important, and for a caring government, option D would be important though the reason may not be immediately obvious. For D, in the case of a country that decides to rely mainly on biofuels, many times more people would have to become involved in the business than for a fossil fuel economy because bio-energy is less efficiently created; long-sighted politicians would need to decide if it would indeed be feasible to divert so much capital and human assets to this end rather than to another part of the economy.

So fundamental is energy to the workings of a society, say Giampietro & Mayumi, that it is not possible to isolate and compare sub-systems such as biodiesel and wind power, without considering the way society itself functions. In other words, the very nature of our society depends on the way that it finds and processes energy. The authors refer to historical examples of civilizations that got it wrong: ruling elites that were no longer able to gain wealth by conquest, would turn inwards to divert more and more internal resources for their own ends, to the point that primary producers (mainly farming communities) collapsed or rebelled. Societies that can no longer afford fossil fuels may in future do the same, and perhaps the increase in land-grabbing that we are seeing in parts of the world is an indication that this has already started3.

Van der Voet et al. conclude that some of the problems with LCA can be fixed by standardizing methodologies. However, there are other limitations with regard to large-scale long-term impacts, where other types of analysis may be more appropriate; for example, land use change as a result of biofuel policies. Aspects such as risk of competition with food crops and local and regional social consequences are outside the scope of present LCA, and they may never be able to include all relevant aspects. However, the concept of social LCAs is being developed. All decision makers should take heed of what the authors say and then read Giampietro & Mayumi’s book to help reorient their thoughts.

LCA of second generation biofuels. When reading LCA papers on the impacts of second generation biofuels, it is sometimes easy to forget that second generation biofuels are not yet commercially available. A new review by Zhu and Pan4 highlights some of the challenges that are faced to commercialise cellulosic ethanol. Despite substantial progress in cellulosic ethanol research and development they say, many problems remain to be overcome. For example, the high energy consumption for biomass pre-treatment remains a challenge. Excellent wood cellulose saccharification efficiency can be achieved using the organosolv process, sulphite pre-treatment to overcome recalcitrance of lignocellulose (SPORL), and steam explosion in the case of hardwood; however improvement in the yield of hemicellulose sugars is still needed. Scaling up the whole process is a key challenge: capital equipment required for commercial demonstrations of some technologies, such as steam explosion, does not yet exist.

Zhu and Pan point out that the pulp and paper industry has the capability and infrastructure for handling biomass on the scale of 1000 ton/day, equivalent to the scale of a future cellulosic ethanol plant of 100 million litres/year, but there is a lack of economic incentive for that industry to shift to a stand-alone biorefinery for ethanol production because fibre for paper is still worth more than ethanol.

Other problems abound: the recovery of pre-treatment chemicals and wastewater treatment are also important issues in selecting commercial production technologies. The dilute acid and acid-catalyzed steam pre-treatment can be performed without the recovery of the acid because of the low cost of sulphuric acid. However, substantial amounts of alkaline chemicals are required to neutralize the pre-treatment hydrolysate. In addition, the salt produced from the neutralization needs to be properly disposed of. Furthermore, the dissolved organics in the stream of post-fermentation pre-treatment hydrolysate represent a significant amount of chemical oxygen demands and needs to be dealt with. On the other hand, the solvent ethanol used in the organosolv process can be easily recovered through distillation, but a significant amount of energy is required using current technology.

Finally, feedstock versatility is another factor to consider. Cellulosic ethanol is a commodity product and cannot afford high-grade feedstock. It is expected that future cellulosic ethanol refineries will have very little flexibility in their choices of feedstock (having to use what is cheap and available at any point in time), therefore the pre-treatment process must be versatile. Pre-treatment processes that are only effective on certain feedstocks will have difficulties in commercial adoption. Challenges in developing integrated forest biorefineries, include how to maintain pulp yield and strength and how to concentrate and ferment the hemicellulosic sugar stream that mainly contains pentose when hardwoods are used.

A new LCA review of switchgrass5, regarded as a promising second generation biofuel, finds that with regard to global warming potential, driving with switchgrass ethanol fuels would lead to less greenhouse gas (GHG) emissions than gasoline: a 65% reduction may be achieved in the case of E85 ethanol fuel. But apart from that, switchgrass would not offer environmental benefits in the other impact categories compared to gasoline. The authors estimate that switchgrass agriculture would become a main contributor to eutrophication, acidification, and eco-toxicity – and emissions from bioethanol production would cause a greater impact in photochemical smog formation.

A further review of LCAs of biofuels from a range of sources of lignocelluloses6, looks at seven impact categories. When it comes to GHG savings, it also finds that switchgrass is the best crop, followed by sugarcane+bagasse (the fibrous residue remaining after sugarcane stalks are crushed to extract their juice), which was included as a comparison. Fuels from corn stover, flax shives and hemp hurds led to a worse performance than gasoline. Sugarcane-derived ethanol turns out to be the best option in terms of photo-chemical oxidation potential (smog) whereas switchgrass and hemp are the poorest. In the category of human and ecotoxicity potential, as well as acidification and eutrophication potential, flax-derived ethanol showed the best environmental performance among all the ethanol fuels.

The authors point out that in many impact categories (global warming potential, photochemical oxidation potential, human and eco-toxicity potential, acidification potential and eutrophication potential) ethanol fuels as a whole do not show advantages over gasoline, so they suggest that strong promotion of bioethanol as a transport fuel needs to be carefully considered. They also suggest that more advanced technologies with optimization of energy use and emissions in both agriculture and ethanol refinery still need to be developed to reduce the current relatively high scores.

The economics of CO2 missions in LCA. In their recent paper, de Gorter and Tsur7 offer a green house gas (GHG)-reduction standard for biofuel production based on a cost–benefit test that allows for a changing carbon price and a positive social discount rate (SDR). They argue that the economic consequences of CO2 emissions and uptakes associated with a biofuel policy must be based on cost–benefit analyses and the latter cannot be adequately addressed by LCA, whether it recognises indirect land use change (iLUC) or not. This is so because LCA is based on the summation of physical GHG balances (where each GHG is weighted by its global warming potential) and the comparison of aggregate emissions with aggregate uptake over a specified period of time (e.g. 30 years). Physical balances summed over many years, however, are devoid of cost–benefit significance for two reasons. First, attaching an economic value (benefit if positive or cost if negative) to a physical quantity requires the use of prices. Second, summing values that accrue at different years requires discounting. Physical GHG balances can be used in cost–benefit tests (in the sense that using them instead of genuine costs and benefits would yield the same cost–benefit criterion) only if (i) the price of carbon (i.e. the price that converts physical quantities into values) is constant over time and (ii) the SDR is zero. Both conditions are inappropriate say the authors: the price of carbon increases over time as long as atmospheric GHG concentration increases (with its ensuing climate-change-induced threats); and a positive (though not necessarily constant) discount rate is required to determine intergenerational tradeoffs when economic growth is expected to persist (even at a reduced rate). Existing biofuel GHG-reduction standards (with or without iLUC) are therefore biased and distort the ensuing policy recommendation.

The impact of the inherent variability of biofuel production systems in LCA. Chiaramonti & Recchia’s recently published paper8 also finds fault with the LCA process. They agree that LCA methodology is a principal tool for the estimation of the impact of biofuel chains and that this is also reflected in the recently issued EU Renewable Energy Directive on the promotion of the use of renewable energy. However, the results of LCAs depend heavily on the quality of the information given as input to the study. In addition, the comparison of a large number of very different aspects (technical, geographical, agronomic), as some LCAs attempt, is a very difficult task due to the extremely large number of variable conditions and parameters. Their paper looks at these problems by considering a very specific biofuel chain: the production and use of sunflower oil in North-Central Italy. Their results showed very large variations in the calculation of the CO2 equivalent emissions, depending on local agricultural practices and performances, even for such a small and well defined biofuel chain. For instance, they graph over 100 different energy input/output field measurements, and reveal an extraordinary variation – a range of ~ 6 to 46 GJ ha-1 input and ~15 to 130 GJ ha-1 output, with no significant relationship between them. They suggest that adoption of the present standardized LCA approach for generalized evaluations in the bioenergy sector should therefore be reconsidered. They recommend that LCA studies, even while addressing very specific and well defined chains, should always include the range of the estimates, since this range of variation of LCA could be significantly greater than the initially set quantitative targets and therefore compromise the whole study. The authors make suggestions for small scale projects to help develop sound but realistic processes to assess biofuel sustainability.

There are growing signs, therefore, that LCAs have a number of methodological difficulties and inconsistencies that urgently need to be addressed. An uncomfortable, but inescapable conclusion is that the systems being measured are so complex and variable, that they can all too easily be tweaked to come to almost any desired conclusion.

Impacts of using crop residues in biofuels production

A major problem of biofuels is that their overall energy gains are often low. This means that in many cases, all crop residues are collected and used to generate additional energy, as so called co-products, and are nearly always counted as such in prospective models of second generation biofuel production. A problem of LCAs is that they often don’t consider the various downsides of doing this. A new review by Blanco-Canqui9 looks specifically at these downsides. He finds that indiscriminate crop residue removal harvesting for expanded uses has adverse impacts on soil properties, water quality, soil organic carbon (SOC) sequestration, and crop production particularly in erodible and sloping soils. Alternatively, he found that growing perennial warm-season grasses (WSGs) and short-rotation woody crops (SRWCs) show promise to provide a range of ecosystem services over crop residue removal. Short-rotation woody crops sequester SOC, reduce soil erosion, improve soil properties, and promote wildlife habitat.

The authors suggest that the benefits of WSGs and SRWCs are greater when grown in marginal, degraded, and abandoned lands than when grown in prime agricultural lands. WSGs and SRWCs as biofuels would have to be carefully managed under such conditions however, to achieve the desired ancillary soil and environmental benefits. Development of sustainable systems of WSGs and SRWCs in marginal lands is a therefore a high priority say the authors.

An agro-ecological approach to second generation biofuel production

As if to reaffirm this point, a new paper by DeHaan et al. 10 reports detailed long-term studies of a field production system for a future grass-based lignocellulosic biofuel. There are two basic approaches to using grasses as biofuels: high input monocultures, or low input high-diversity grassland. The former is potentially easier to develop as a high yielding system, where high yielding strains can be continuously improved and deployed over time to give predictable performance. However, the latter scheme has many advantages since, low inputs decrease costs and pollution caused by those inputs, and there is an increase in biodiversity.

The authors looked at the relative yields from 168 plots in Minnesota where they varied the number of indigenous grass species. For some treatments they also included some leguminous species. Overall they found that the greater the number of grass species used (up to 16), the greater the yield, but the range of variation in yield was very high. Plots with legumes and grasses performed the best. Motivated by a desire to make future practical recommendations to farmers, they then calculated the minimum species number necessary for the system to have predictably high yields. They estimated that combinations of just one grass and the best performing legume (Lupinus perrenis) gave a performance as good as high diversity grass plots.

In practice, such ‘bi-cultures’ of one grass and legume species could be arranged so that the legume species is evenly distributed within a field, or the legumes could be grown in patches, fed to livestock, and the manure used to fertilize the grasses. With a sustained effort to breed and develop legume/C4 grass bi-cultures, plant breeders and agronomists might develop systems that are increasingly productive and mostly free from dependence on nitrogen fertilizers.

Clearly this is not a high diversity solution so the authors suggest an intriguing compromise. One strategy would be to develop numerous lower diversity systems and deploy them in a patchwork arrangement to achieve landscape-level diversity. Or, farmers could be paid to add noneconomic species to their fields solely to increase biodiversity. The authors also assert that this is not the final word: further research might show that the addition of other selected species to improved bi-cultures could increase their yields and the stability of these yields. This paper is therefore a very encouraging blend of agro-ecological theory, field experimentation and commercial awareness that many other researchers could learn from.

Jatropha update

We have just received a useful review of the present status of jatropha cultivation in Mexico and Central America11. This is the centre of origin of the plant and one of the first jatropha projects was started in Nicaragua in 1990, though it was abandoned in 1999. In this short review, Cifuentes & Fallot report that about 7,400 ha are currently under cultivation in seven countries of the region. The authors affirm the interest in jatropha throughout the region but point to the need to develop better regulatory frameworks and value chains in order to attract proper finance. Most of the projects they identify are no more than three years old and they suggest that much better dissemination of the data from these projects is required to show that the predicted yields are in fact achievable. Selection of varieties and development of technological packages appropriate to each country are also need, they suggest.

The need for better data from projects is a common deficiency and one that a recent report by GTZ tackles with some vigour12. It looks at the economics of jatropha growing for smallholders in Kenya and its conclusions are uncompromising:

‘The results of this survey, taken from interviews with hundreds of Jatropha farmers throughout Kenya, show extremely low yields and generally uneconomical costs of production. Based on our findings, Jatropha currently does not appear to be economically viable for smallholder farming when grown either within a monoculture or intercrop plantation model.

The only model for growing Jatropha that makes economic sense for smallholders, according to actual experiences in the field so far; this is growing it as a natural or live fence with very few inputs. Of course, this is precisely how Jatropha has been grown in this part of the world since it was introduced centuries ago.

Therefore, we recommend that the all stakeholders carefully re-evaluate their current activities promoting Jatropha as a promising bioenergy feedstock. We also suggest that all public and private sector actors for the time being cease promoting the crop among smallholder farmers for any plantation other than as a fence.

Although these conclusions provide a sobering retort to some of the unbridled hype that has swirled around Jatropha over the past few years, current research and development may lead to improved varieties. What is clear from the results of this field survey, however, is that that day has not yet arrived.’

The GTZ study uses the word ‘hype’ to describe the interest in jatropha and coincidentally the same word is also employed in another recent review of jatropha by Achten et al13. They write that ‘Popular claims on drought tolerance, low nutrient requirement, pest and disease resistance and high yields have triggered a jatropha hype with sky-high expectations on simultaneous wasteland reclamation, fuel production, poverty reduction and large returns on investments.’ Many of these claims are yet to be supported by scientific evidence, the authors conclude. They point to major knowledge gaps concerning basic ecological and agronomic properties (growth conditions, input responsiveness of biomass production, seed yield and the species’ genetics), that make seed yield poorly predictable. Considering the current expansion, this situation might hold considerable sustainability risks (economic, social and environmental). Among other issues, the water requirement and water footprint of jatropha are still poorly understood. A better knowledge of these agronomic properties is vital for the further application of the species. Jatropha should therefore still be considered a (semi-) wild, undomesticated plant showing considerable performance variability.

The authors highlight some potential breeding problems with this poisonous bush that might account for its notoriously variable yield: jatropha can set seed after both insect and self-pollination. However, self-pollinated fruits are lighter in general and abort before maturation in 25% of cases. It has been suggested that this could be due to early acting inbreeding depression and thus may reflect a high natural out-crossing rate. Preliminary studies indicate very low variation in microsatellite simple sequence repeat (SSR) markers within populations even of Mexican Jatropha. This is surprising since Mexico is the purported centre of origin of the species, and hence where you would expect genetically diverse populations to be found.

The authors point out that understanding the breeding pattern is central for design of domestication strategies. Breeding, large-scale mass propagation and distribution across landscapes will be much easier if the species is reproduced by natural selfing without inbreeding depression or, especially, if it reproduces by apomixis (asexual reproduction without fertilization). Given the successive introductions of jatropha and its ability of clonal mass propagation within a short time, it is possible that all African and/or Asian populations result from a narrow germplasm origin. Recent studies based on genetic markers uncovered surprisingly low levels of genetic diversity in jatropha landraces from China for instance. The authors suggest that, given the low genomic diversity in landraces, ‘smart’ out-crossing between superior Asian individuals with new introductions from the Americas should be performed. Such crosses should release any inbreeding depression and thereby increase vigour and fruit production if genetic diversity of American landraces is effectively larger.

The authors detail a number of steps that are needed to develop a breeding programme that might lead to reliable heavy yielding tree stocks. We recommend all those working on jatropha to read the paper and the GTZ report as two detailed and well argued contributions to the growing literature on this plant.

Jatropha mosaic disease
A paper by Gao et al. 14, reports the completion of the nucleotide sequence of the jatropha mosaic disease, which has emerged recently and now widely spread in India. Phylogenetic analysis of the virus genome suggests it is a new strain of Indian cassava mosaic virus. It is always unfortunate to have a single disease that affects two different crops, since this tends to make control of both more difficult. However, the authors suggest that with the genome sequenced information and the availability of the two infectious clones, it may be possible to use double-stranded hairpin RNA or artificial miRNA-mediated RNA interfering technology to generate transgenic Jatropha lines that are resistant to this new disease.

Microbial contamination of biofuels

Although it probably shouldn’t, it comes as a surprise to discover the amount of bacterial contaminants in the bioethanol industry. A new paper by Muthaiyan and Ricke15 reveals that in the process of scaling up ethanol production, bacterial contamination is becoming one of the more challenging problems facing the industry. The management of contaminants is often achieved in the bioethanol industry by using antibiotics such as penicillin G, streptomycin, tetracycline, virginiamycin, and monensin or mixtures of these compounds. Currently, penicillin and virginiamycin are commercially sold to treat bacterial infections of fuel ethanol fermentations, and some facilities use these antibiotics prophylactically. Of the antibiotics available, virginiamycin is considered one of the better choices for treatment since this antibiotic, unlike penicillin, retains its activity at lower pH values.

The authors question the concept of antibiotics use in an industrial process because of the considerable cost of adding large quantities of antibiotics and the rapid emergence of antibiotic resistance among the contaminant bacteria. This scenario represents potential public health consequences and therefore requires more research on the impacts of the bulk usage of antibiotics in bioethanol fermentation on antibiotic resistance in public health system. To avoid such a public health consequence consideration of better strategies by alternative means to control contaminants and much earlier detection of initial contamination long before drastic measures such as complete shutdown of the fermenter are required.

This paper therefore again reminds us of the ineluctable complexity of biofuel production: unlike gasoline which has rather few microbial contaminants, biofuels will always be more susceptible because there are many co-evolved organisms in the environment that will attack them and any method to control them will expend yet more energy on systems that struggle to achieve efficiency. It shows yet again that LCAs, which as far as we know never consider future problems of microbial contamination, are an imperfect tool to fully evaluate the utility of biofuels and the broader implications for society.

van der Voet, E., Lifset, R.J. & Luo, L. (2010) Life-cycle assessment of biofuels, convergence and divergence. Biofuels 1(3): 435–449.

Giampietro, M. & Mayumi, K. (2009) The Biofuel Delusion. Earthscan, London. 318pp.

Africa: up for grabs. The scale and impact of land grabbing for agrofuels (August 2010). Report Friends of the Earth Africa and Friends of the Earth Europe.

Zhu, J.Y. & Pan X.J. (2010) Woody biomass pretreatment for cellulosic ethanol production: Technology and energy consumption evaluation. Bioresource Technology. 101: 4992–5002

Bai, Y., Luo, L. & van der Voet, E. (2010) Life cycle assessment of switchgrass-derived ethanol as transport fuel. International Journal of Life Cycle Assessment. 15: 468–477.

Luo, L., Voet, E. & Huppes, G. (2010) Energy and Environmental Performance of Bioethanol from Different Lignocelluloses. International Journal of Chemical Engineering. 2010: 12pp.

de Gorter, H. & Tsur, Y. (2010) Cost–benefit tests for GHG emissions from biofuel production. European Review of Agricultural Economics. 37: 133–145.

Chiaramonti, D. & Recchia, L. (2010) Is life cycle assessment (LCA) a suitable method for quantitative CO2 saving estimations? The impact of field input on the LCA results for a pure vegetable oil chain. Biomass & Bioenergy. 34(5): 787-797.

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