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Wild potato genes in fight against late blight
Scientists at the International Potato Center (CIP) have identified a large number of
genes from a wild potato species that are potentially useful for breeding for resistance to
late blight, a disease that causes annual global losses to potato production of up to
US$5 billion. Results of a study, recently published by CIP scientists in Molecular Plant
Pathology, have revealed that when S. cajamarquense plants were inoculated with an
extremely virulent pathogen strain found in Peru, the plants were found to be highly
resistant, showing only small diseased lesions in few plants. "Wild potatoes are
important because their full genetic potential is as yet untapped for agriculture," says
Meredith Bonierbale, Head of CIP's Germplasm Enhancement and Crop Improvement
Division. "Many genes conferring resistance to today's major pests were left behind in
the processes of domestication and crop improvement."
Experiments more than ten years ago at CIP's highland station at Huancayo, Peru first
flagged the potential for rare wild species, reporting evidence of resistance to late blight
in seven species endemic to the South American centre of origin of potatoes. "Right
now, we have several wild species under investigation," explains CIP plant pathologist
Willmer Perez. "To date we've only tested about 40 per cent of all the germplasm that
we have in the genebank collection. That leaves 60 per cent still untapped. They are, in
effect, a kind of secret weapon."
Capturing the diversity of wild potatoes and transferring the traits to cultivated varieties
remains a complex and lengthy endeavor. CIP breeders are currently working to adapt
and routinely apply in vitro technologies, such as embryo rescue, to facilitate the
process of crossing wild potatoes with cultivated varieties. Wild potatoes also offer a
rich source of resistance to other diseases and abiotic stresses, such as drought and
salinity. But with FAO forecasting that the area where they are able to grow may be
reduced by as much as 70 per cent due to climate change, it is imperative that these
genetic gems are preserved and investigated now.
Maize rough dwarf virus yet to be an epidemic
With the severity and spread of maize rough dwarf virus (MRDV) still confined to a
relatively small area in Uganda, scientists have indicated that the disease has yet to
reach epidemic levels or to severely impact maize production in East Africa. The
International Maize and Wheat Improvement Centre (CIMMYT) opinion is that maize
streak virus and northern leaf blight remain more important to the scientific community
and farmers due to their widespread coverage in East Africa. But in affected areas of
Uganda, MRDV has reduced yields by 20-30 per cent.
Dr. Stephen Mugo, senior scientist and maize breeder at CIMMYT-Kenya, explains that
resistant maize plants are the best option for farmers, but in the short term delayed
sowing and efforts to kill the virus-carrying plant hoppers about 20-30 days before
maize is planted will offer adequate control of the disease. Affected farmers are already
uprooting and burning infected crops in an effort to contain the spread of the disease.
"We need to understand the disease to control it," Mugo says. But like all plant
diseases, Mugo asserts that technical and financial constraints will delay development
of chemical pesticides and pest-resistant seeds.
The virus causes galls to develop on the underside of leaves along the veins, leading to
severe stunting and dwarfing, malformed leaves, restriction of root development and a
reduction in the yield of fodder and grain. MRDV was first identified early this year in
Masindi district and Namulonge in Uganda.
United against hunger
Despite recent gains that have reduced the number of people who suffer from chronic
hunger from 1 billion in 2009 to 900 million in 2010, FAO and WFP report that the
number of hungry people in the world remains unacceptably high. "With a child dying
every six seconds because of undernourishment-related problems, hunger remains the
world's largest tragedy and scandal," says FAO director general Jacques Diouf. "This is
absolutely unacceptable." In a new hunger report published in the run-up to World Food
Day (16thOctober), the UN agencies blame natural disasters, conflict and weak
institutions for causing repeated food crises and extremely high levels of hunger in 22
countries in 2010.
According to the newly published Global Hunger Index, malnutrition among children
under the age of two is one of the leading challenges to reducing global hunger.
Countries in sub-Saharan Africa and in Asia were shown to have the highest levels of
hunger, with 29 countries identified as having levels of hunger that are 'extremely
alarming' or 'alarming'. Conflict, political instability and high rates of HIV and AIDS are
among some of the major challenges identified for sub-Saharan Africa. The report
suggests that child malnutrition could be cut by a third by providing healthcare and
nutrition to young children and their mothers during pregnancy and breastfeeding.
"It is shameful that ten years since world leaders vowed to halve global hunger by 2015,
we are no closer towards achieving this goal," says Oxfam's director of campaigns and
policy, Phil Bloomer. Halving hunger is still possible, a new Oxfam report concludes, but
only if developing countries take the lead with the right policies and investments, if
donor countries dramatically increase aid for agriculture, food security and social
protection, and if the global issues affecting food security are collectively addressed.
"We know it is possible, we know how it can be done, but what is missing is the political
will," Bloomer adds.
Colombia tackling coconut diseases
Colombia's coconut farmers are facing a double assault from two diseases which kill
coconut palms. In the south of the country, Red Ring Disease has already killed up to
80 per cent of palms in Nariño and Cauca. Meanwhile, scientists have warned
that Lethal Yellowing Disease will spread down from Central America, where it has
already killed millions of palms in Mexico and Honduras.
To tackle this 'disease squeeze', the International Center for Tropical Agriculture (CIAT)
has teamed up with several partners to help scientists quickly find sustainable and
eco-efficient solutions. "We must take these kinds of disease threats extremely seriously
and act as a matter of urgency to help small farmers," says Alonso González, leader of
CIAT's tropical fruits program. Coconut is an important cash crop and source of food for
many farmers, particularly in remote jungle areas on the Pacific coast where soils are
poor and rains are heavy year-round.
In addition to propagating coconut germplasm and using tissue culture techniques to
speed up the research process, scientists are also investigating possible genetic
resistance to Lethal Yellowing in the 'high palms' native to Mexico, and developing
methods to test for resistance to Red Ring Disease more rapidly. "The good news is we
have some very promising possibilities, but funds are required to expand the
international collaboration, to test a broad case of coconut genetic resources, and
facilitate the exchange of germplasm among countries," González adds.
Causing trees to wither and die, Red Ring Disease is caused by a nematode
(Bursaphelenchus cocophilus L.), which is carried by the palm weevil (Rhynchophorus
palmarum L.). Lethal Yellowing is caused by pathogens spread by planthopper insects,
and results in the loss of flowers, fruits and leaves, killing palms in a few months.
Scientists control water hyacinth with weevils
Weevils have been introduced by scientists into the Mono River, in Benin, to limit the
spread of water hyacinth, the invasive plant now found in waterways across Africa.
"These weevils feed only on water hyacinth and proved to be effective biocontrol agents
of the water weed when used in the Oueme River eight years ago," says Obinna
Ajuonu, a scientist with the International Institute of Tropical Agriculture (IITA), "So we
are confident this approach will yield results."
Floating freely, mats of water hyacinth double in size every four to seven days,
obstructing electricity generation, irrigation, navigation and fishing. The weed also
increases diseases such as bilharzia and water loss resulting from evapotranspiration.
In Sudan, it has been estimated that more than 400 hectares could be irrigated with the
annual water loss from evapotranspiration (from water hyacinth) over 300 square
kilometres of the Nile.
Mass-produced by the Department of Agriculture in Porto-Novo, the weevils Neochetina eichhorniae and N. bruchi - were bred using a start-up colony supplied by
IITA, which also provided technical assistance. Although it may take some years for the
impact to be seen, Ajounu explains that the weevils are environmentally friendly and
more economical than other control methods.
African governments urged to increase uptake of drought tolerant maize
Researchers have called on African governments to encourage the development of
private seed companies and improve input, pricing and marketing policies to increase
the uptake of Drought Tolerant Maize (DTMA) varieties across sub-Saharan Africa. With
the potential to increase yields by 20 to 30 per cent, the International Maize and Wheat
Improvement Center (CIMMYT) and International Institute of Tropical Agriculture (IITA)
estimate that DTMA could generate an additional US$1.5 billion if existing maize
varieties were completely replaced.
Uptake of DTMA in Benin has remained low at 20 per cent, compared to 85 per cent in
Kenya. Wilfred Mwangi, head of CIMMYT's global maize program, attributes this
difference to Kenya's vibrant privately-owned seed industry. "Governments must
support investment in seed companies and also strengthen community-based seed
producers including community-based organisations and NGOs to increase adoption,"
he says. Mwangi also recommends government subsidies to tackle high seed prices. "It
has been done in Malawi and Kenya with good results," he states. "This is the way to go
for Africa."
Low returns and unfair prices for maize grain also discourage farmers from investing in
quality seeds, say IITA plant breeders, Sam Ajala and Baffour Badu-Aparaku.
Recommendations include on-farm storage facilities to reduce waste, de-regulation of
grain markets to allow maize exports and encouragement for seed companies buy back
surplus maize. CIMMYT and IITA also call for extensive on-farm testing and
demonstration by national research and extension bodies, training for seed company
staff, increases in volumes of breeder seed and educational campaigns to increase
uptake.
Farmers must be put first in farm radio production
To improve the effectiveness of farm radio, farmers must be put first, access to radio
broadcasts must increase and specialised training for radio producers must be
provided, participants at the 2010 Malawi Farm Radio Symposium recently concluded.
Effective radio "is beyond knowing how to handle a microphone and getting people to sit
around a table," said Professor Kamlongera from the University of Malawi. "Farmers
know the answers to the problems they face, but do we even bother to find out what
they know? Can we then add value to what they know as the basis of our
communication with them?"
Symposium participants endorsed the suggestion that farm radio producers require
specialised accreditation and training to enable them to communicate effectively with
farmers. Studies to learn more about access, utilisation and benefits of farm radio for
women were highlighted as a priority, in addition to the promotion of listening groups
and radios that do not require batteries, to ensure that all farmers can access
broadcasts. Lobbying mobile phone service providers to offer subsidised rates and
thereby enable listeners to communicate more effectively with farm radio producers was
also endorsed.
To strengthen communities' capacity to engage in public debates and influence action
on climate change, meteorologist Elina Kululanga recommended the formation of radio
citizen clubs. By meeting regularly to share their knowledge and experience on a series
of common themes that integrate climate change into day-to-day farming practices,
listening groups would be able to ensure that listener feedback was placed at the centre
of radio programming, Kululanga asserted.
Restoring land with agroforestry in North Korea
Degraded land on the sloping lands of North Korea's mountains is being restored by
communities who are diversifying their crops with the help of a pioneering agroforestry
project. Only 16 per cent of Korea's land is suitable for cultivation. After the collapse of
the Soviet Union in 1989 and a lack of agricultural subsidies caused widespread famine
and malnutrition, many communities had to resort to cultivating the fragile mountainous
slopes to survive. As land was stripped of trees to provide fuelwood or land for cropping,
the slopes have been increasingly degraded and depleted of nutrients.
To stabilise and restore the soil, the Swiss Agency for Development and Cooperation,
Korea's Ministry of Land and Environmental Protection and the World Agroforestry
Centre, have been promoting the use of multi-purpose trees to provide fertiliser, fodder
or fruits. To produce their own planting materials, some community groups have
established their own nurseries. "Previously malnourished communities are now
producing their own trees and growing chestnut, walnut, peaches, pears and other fruits
and berries as well as medicinal bushes," explains Jianchu Xu, East-Asia coordinator
for the World Agroforestry Centre. "They have more food and vitamins and are earning
income through trading."
Since 2002, three user groups in Suan County have expanded to 65 groups in seven
counties with several hundreds of hectares now under sustainable management.
Representatives from the national academy, agricultural universities, forestry research,
planning institutes and staff of the Ministry have also been provided with training to
improve knowledge and skills in natural resource management. An agroforestry manual
and agroforestry policy for management of sloping lands are also in the process of
being developed.
New coffee variety offers bright future to Kenya growers
Production of Kenya's smallholder Arabica coffee is set to receive a boost with the
launch of a new coffee variety that is resistant to Coffee Berry Disease (CBD) and
Coffee rust. Known as 'Batian', the new variety has been developed by the Coffee
Research Foundation (CRF) and is reported to reduce production costs by 30 per cent.
"These are appreciable savings for farmers who have to cope with the cost of fungicides
and labour used to control CBD and leaf rust," says CRF director Joseph Kimemia.
"Batian is also a high yielding variety with good bean and cup quality. It is also well
suited for all coffee agro-ecological zones in Kenya."
Speaking to New Agriculturist, Kimemia said that Batian offers farmers an opportunity to
increase their production and expand Kenya's market share in the international market.
"Farmers are currently harvesting around two metric tonnes of coffee per hectare,
although sometimes yields are as low as half a tonne. The new variety yields up to five
tonnes per hectare by the fourth year, when production is at its peak." He added that
Batian also takes a shorter time to mature, and farmers can start harvesting the crop by
the end of the second year.
Well known for its intense flavor, full body, and pleasant aroma, Kenya's Arabica coffee
is predominantly produced by smallholders. However, during the last two decades,
coffee production has dropped by almost 60 per cent, with around 50,000 tonnes
produced each year. Kenya has a popular disease-resistant hybrid called Ruiru 11, but
some coffee experts say it lacks the rich aroma of the variety SL28, which was
introduced in the 1900s. Kimemia said those who had cupped Batian had termed it 'as
of excellent character', adding that the new variety offers a good opportunity for
upcoming coffee-growing areas in the northern Rift.
African freshwater species under threat
Agriculture, water abstraction, dams and invasive species are putting over 20 per cent
of African freshwater species at risk from extinction, the International Union for
Conservation of Nature (IUCN) has warned. "Africa is home to an astonishingly diverse
range of freshwater species, many of which are found nowhere else on earth," explains
William Darwall, manager of IUCN's freshwater biodiversity unit. "If we don't stem the
loss of these species, not only will the richness of Africa's biodiversity be reduced
forever, but millions of people will lose a key source of income, food and materials."
In Lake Victoria, IUCN report that a decline in water quality and the introduction of the
Nile Perch (Lates niloticus) have led to the decline in native species over the last 30
years, threatening the livelihoods of traditional fisheries. The assessment carried out for
the IUCN Red List of Threatened Species™, found that 45 per cent of the fish
species in the Lake are threatened or thought to be extinct. In Lake Malawi, the
population of the Oreochromis karongae - an important source of food - has dropped by
70 per cent over the past ten years as a result of overfishing.
By highlighting priority areas, it is hoped that this new data will help to safeguard the
fisheries and freshwater supplies that are currently under threat. "This new study gives
us a unique opportunity to try to influence developers and governments when they're
planning freshwater infrastructure projects, which are still in the early stages in most of
Africa," says Anada Tiéga, secretary general of the Ramsar Convention on Wetlands.
"Armed with these assessments, we hope that decision-makers in Africa will now make
the right choices to develop their water resources in a sustainable manner whilst
protecting and valuing global biodiversity."
A new certification scheme for sustainable cattle farms
A new standard for cattle farms that promotes sustainable production to help mitigate
deforestation, greenhouse gas emissions and animal cruelty has been launched by the
Rainforest Alliance and the United States Agency for International Development
(USAID). "You can combine conservation and cattle production," explains Oliver Bach,
Rainforest Alliance standards and policy manager. "Tree cover, for example, not only
provides habitats for birds and insects, but it is also good at reducing heat stress for
cattle and providing leaves and fruits for fodder."
Developed during a two-year public consultation process involving stakeholders from 34
countries, the standards will be applied to farms located in tropical regions of Latin
America, Africa, Asia and Oceania. However, only farms where cattle have access to
pasture will be eligible for the scheme. The 'Standard for Sustainable Cattle Production
Systems' will enable farmers to use the Rainforest Alliance Certified™ guarantee
to market beef, dairy and leather products. "The Rainforest Alliance seal of approval will
inform consumers that these farms are conscious about the environment and climate
change," Bach adds.
In order to reduce greenhouse gas emissions, the Rainforest Alliance is promoting three
practical actions: improving cattle's diets, treating their manure and conserving trees to
capture carbon dioxide. "Selecting different fodder species that are easier to digest will
reduce methane emissions and conserve the soil in the long-term," Bach explains.
Integrated management systems, sustainable pasture management, labour welfare
standards, animal welfare and carbon-footprint reduction are all part of the criteria for
achieving Rainforest Alliance certification.
IFPRI warning over food price fears
Growing panic that another food price crisis could occur is unjustified and could hurt
poor people, claims the International Food Policy Research Intuition (IFPRI), despite
fears over volatile wheat prices, riots in Mozambique over food prices and the banning
of Russian wheat exports until 2011. "Apparent similarities between today's rising wheat
prices and the food-price crisis of 2007-2008 are just that: apparent, not real," states
Maximo Torero, director of the markets, trade and institutions division at the
International Food Policy Research Intuition (IFPRI). "Suggestions to the contrary serve
to drive up prices and hurt poor people, who spend much or most of their incomes on
food. They need neither jittery markets nor ad hoc protectionism, which has
exacerbated past food crises."
Media reports that tied the unrest in Mozambique to the price of wheat were wrong to do
so, Torero added. Instead, the higher cost of bread was the result of Mozambique's
currency weakening against the South African rand, making imports from South Africa
much more costly. "More thoughtful analysis has followed in recent days but not until
after the earlier, more reflexive narrative had already caused another global price
spike." Torero says. "That was the last thing consumers - especially poor ones needed."
To drive up food prices in the long term, wheat prices would have to stay high for a long
period, as happened in 2007. However, prices are currently under constant change.
"Volatility is not the same thing as inflation," Torero explains. "Recent spikes
notwithstanding, the prevailing trend is flat or slightly downward. In consequence, there
should be no knock-on effects." In addition, Torero noted that while Russia lost a
significant portion of their wheat crop, the United States, Argentina, Australia India and
Uzbekistan have all enjoyed good harvests. Wheat stocks are also significantly higher
than they were in 2007-2008, more than covering the losses from Russia, Ukraine,
Kazakhstan and the European Union.
Revitalising Maya nut in the Caribbean
An institute dedicated to the promotion of Maya nut has expanded its activities into
Jamaica and Haiti to teach rural women about the propagation, nutrition and processing
of Maya nut. Extinct in Haiti for more than 200 years, the Maya nut is now being
re-introduced by the Maya Nut Institute. Although less than five per cent of the first
batch of seed sent from Guatemala for reforestation survived, 35 seedlings have been
successfully established. Although the trees will take time to mature and provide fruit,
over 80 women from 34 communities have been trained to process and prepare dry
seed into a variety of local dishes, including sauces, ginger cookies, patties and drinks,
to develop their business skills and create a market. With further funding, the Institute
plans to provide more seed for reforestation as well as dry seed for use by the women.
As a result of discovering extensive Maya nut forests in Jamaica in April 2010, the
Institute is also working with the Jamaican Forestry Department. Since raising
awareness of the importance of Maya nut as a valuable source of food and fodder, the
Forestry Department has incorporated Maya nut trees into its reforestation programmes.
"Because our mission is to rescue lost indigenous knowledge about the Maya nut
throughout its native range, our vision is to continually expand to new sites," explains
Erika Vohman from the Maya Nut Institute. "Teaching rural people, governments and
land managers about the food and fodder potential of the Maya nut tree helps to
improve health, create jobs and income for women, and motivate conservation and
interest in reforestation."
Improved water storage to reduce impact of climate change
Millions of farmers, dependent on rainfed agriculture, require diverse forms of water
storage in order to cope with decreasing and erratic water availability due to climate
change, a new report from the International Water Management Institute (IWMI) states.
"Reliable access to water can make all the difference between chronic hunger and
steady progress toward food security," explains Matthew McCartney, a hydrologist at
IMWI and lead author of the report. "Even small amounts of stored water, by enabling
crops and livestock to survive dry periods, can produce large gains in agricultural
productivity."
Arguing against an overreliance on single solutions, such as big dams, the report calls
for an integrated approach, combining both large and small scale options including
water from wetlands, water stored in the soil, groundwater and water collected in ponds,
tanks and reservoirs. Studies have shown that in Zimbabwe and Niger, the use of small
planting basins to harvest water has boosted maize and millet yields. And in Rajasthan,
India, the construction of 10,000 water harvesting structures has enabled 70,000 people
to irrigate 14,000 hectares and grow vegetables and other cash crops. "Unless we can
reduce crippling uncertainty in rainfed agriculture through better water storage,"
McCartney adds, "many farmers in developing countries will face a losing battle with a
more hostile and unpredictable climate."