Crops, forest products, pest control
Crop pests and diseases
Research reports for "weed management"
Crop pests and diseases
Research reports for "weed management"
- Boosting lowland rice yields and banishing weeds
New ways to control weeds and plant rice using direct-seeding have great potential to increase rice harvests in Bangladesh. At the moment, one-third of farmers lose half a tonne of rice per hectare because of weeds. Now, a range of cost-effective weed management practices have been validated, which include applying herbicides or using a manual rotary weeder. Yields are the same or better than with normal hand-weeding, but costs are 30-45% less. Direct-seeding has also proved valuable in drought-prone areas. It gives earlier rice harvests, allows farmers to grow a second crop, and reduces outlays on irrigation water and labour. Extensionists and NGOs are already spreading the word, and training manuals, leaflets and posters for pesticide-dealers’ stores are available. (Ref: CPP30) - Imported fungi help farmers defend themselves against invasive weeds
A rust fungus collected in Trinidad and Peru is helping to control Mikania micrantha in southwest and northeast India. Previously, this invasive (‘mile-a-minute’) weed smothered vegetation over vast areas of tropical forests. Smallholder farmers can now fight back using biological control methods. The Indian Government provided a national framework for the project and sponsored public awareness activities to promote understanding of the control technology. Indian scientists and extension workers received training and are now undertaking on-going monitoring programmes. The rust fungus is being mass-produced in specially built facilities for wide release on the continent. Scientists in China, Fiji, Taiwan and Papua New Guinea are also using the technique, and many other countries have expressed interest. (Ref: CPP06) - New opportunities for cotton croppers in Sub-Saharan Africa
A range of crop and pest management technologies have been tested in Uganda and Zimbabwe and are now available to make cotton growing more profitable in Sub-Saharan Africa. These go hand in hand with easy-to-understand tools like manuals and identification sheets. One of the most innovative aspects of the project was the partnership that it formed with private cotton-processing companies (ginneries) to disseminate the results to farmers and provide them with new opportunities. To this end, around 600 ginnery staff were trained in integrated pest management. They then went on to provide training to 6000 farmers hosting on-farm cotton demonstrations. (Ref: CPP39) - Ploughs, hoes and cheap herbicides beat weeds in cotton
Smallholder cotton growers in Zimbabwe now use low-cost techniques to control weeds. In the Zambezi Valley, the rainy season is short and hot. If farmers don’t weed promptly and thoroughly, they can lose nearly all their crop. Previously, controlling weeds needed lots of labour for constant weeding. In the Lower Zambezi Valley and South East Lowveld of Zimbabwe, farmers now beat weeds by ploughing before planting, hand hoeing and applying low-cost herbicides - techniques within their means and that save labour. Extension services now routinely advise farmers that this is a good way to deal with weeds and universities teach this system in their courses. Plus, inquiries from South Africa, Mozambique, Tanzania, Uganda, Kenya, Pakistan, Slovenia, Togo and Brazil are pouring in. (Ref: CPP67) - Simple labour-saving ways to boost maize and rice harvests in southern Africa
Farmers in dry uplands in southern Africa mainly grow maize. In wetlands, where their fields flood in the rainy season, they intercrop maize with rice. But maize and rice are labour-intensive and harvests were poor. Now, farmers use simple labour-saving practices and work their oxen more effectively. New farmer groups in Masvingo, Zimuto, Mshagashe, Chatsworth and Chivito, Zimbabwe, are spreading the word that soaking seeds, planting on ridges to combat waterlogging, ridging fields to get rid of weeds, and conserving moisture in furrows and pits saves work and boosts harvests. The Universities of Zimbabwe and Gweru, and agricultural colleges also now teach these and other practices. Plus, seeing the benefits for themselves, farmers are quick to copy what obviously works. (Ref: CPP48) - ‘Off-the-shelf’ biocontrol for weeds in India
Scientists in India now have the skills to screen and use biological controls for pests. The exotic noxious weed Parthenium not only causes severe crop losses but also affects people - causing contact dermatitis and allergies. Already used in many countries, biological controls for weeds are sustainable and environmentally friendly. Now, Indian scientists have successfully imported, screened and released a rust to control Parthenium. Proven in UK and Australia, this opens the door for other ‘off-the-shelf’ pest controls to be introduced. Biological controls could have a major impact on raising incomes of the poor, helping them to use less pesticide and boost crop yields. Interest in these biological control methods is now spreading throughout Asia. (Ref: CPP71) - Controlling wild rice infestations in cultivated rice
New practices for managing infestations of wild rice species in lowland rice in West and East Africa have been developed and validated by farmers. Such infestations can reduce rice yields by up to 2 tonnes per hectare, and require a lot of labour for weeding. Plus, rice contaminated with seeds of wild species sells for only half the market price. In Ghana, farmers preferred to spray with glyphosate before planting, or to switch to transplanting in bunded fields if they couldn’t afford herbicide. In Tanzania, farmers took up a reduced tillage-plus-herbicide system as it was a cost-effective labour-saving option that could even reclaim land previously abandoned to wild rice. These practical options are ready for out-scaling to large areas, and extension materials already exist. (Ref: CPP31) - Direct-seeded rice saves money, water and labour
A suite of new techniques associated with direct-seeding of rice has the potential to secure and sustain India’s rice bowl—the Indo Gangetic Plains. The time is ripe for alternatives to transplanted irrigated rice, as the system used now is threatened by increasing shortages of irrigation water, higher energy costs, and the rising cost of labour. Recommendations on managing weeds, and on how and when to plant, have been produced for areas with different soils, rainfall and ploughing methods. Plus, decision-support tools are available for extension workers and farmers that present the choice of technology options for direct-seeded rice in a farmer-friendly way. (Ref: CPP29) - Improving information on rice pests and diseases in Bangladesh
A computer programme to record and analyse information on pests and diseases will help agricultural departments in Bangladesh alert farmers quickly to threats. The new system speeds up the time it takes for data from districts to be analysed and the results fed back to the local offices. This means early warnings for farmers who can then take action. As it’s based on the old paper system, the new system is very user-friendly. Proven for rice pests and diseases in Bangladesh, the software could also be used for other crops, and even across borders. Indian authorities are already interested in using the software to monitor pests in the border area with Bangladesh. (Ref: CPP61) - Legume rotations improve fertility and help control witchweed
Farmers in eastern and southern Africa could double their yields simply by growing legumes for a year in between cereal crops. Two problems that cause low yields are poor soil fertility and the rampant witchweed, Striga. Rising populations in rural areas mean that land is cropped more intensively. So farmers plant cereals - maize, upland rice, sorghum and finger millet - year after year, instead of leaving the land crop-free to recover and to help control witchweed. Villagers in Kyela, Morogoro and Mbeya in Tanzania now rotate cereals and legumes. They dig in the legumes as green manure. In rice–legume rotations, witchweed dropped by half. These rotations could have a major impact in the region, as many poor farmers cannot afford fertilizers or herbicides. (Ref: CPP66) - Push-pull deals with pests and improves soils
‘Push–pull’ pest management means growing plants that repel pests together with those that attract and kill them. One of these partnerships, Napier grass and the legume Desmodium, prevent stemborer and witchweed in maize. These push–pull partners are also good fodder crops and improve soil fertility. Other integrated pest and soil management strategies proven in Kenya, Uganda, Tanzania, Malawi, Ethiopia and Nigeria are now available for small farmers to improve mixed maize–livestock systems - crop rotation, intercropping, manure and fertilizer, dual-purpose grain legumes and resistant varieties. Over 6000 smallholders in Kenya and Tanzania already use environmentally friendly push–pull methods to control witchweed and stemborer, improve soils, and grow more fodder for livestock. These technologies have great potential for other cereals, particularly sorghum and millet. (Ref: CPP52) - Weed pest no longer a bottleneck in raising rice-wheat productivity
Thousands of farmers in rice–wheat areas of the Indo-Gangetic Plains now practice reduced tillage to control the weed Phalaris minor. This pest was a major bottleneck in raising yields. Previously, farmers didn’t understand how long the weed seeds survived in the soil and what caused them to start growing. Now, they’ve stopped ploughing their fields because they know that this encourages the weed seeds to germinate. Farmers in Haryana State and Punjab, India, successfully used low tillage to control Phalaris. The technique has already spread throughout the Indo-Gangetic Plains in India, Pakistan, Nepal and Bangladesh. Besides curbing the weed, low tillage also reduces erosion, improves soil fertility and lowers input costs - fuel, farm machinery and labour. (Ref: CPP72)
Crop pests and diseases
