Study: More IPM Knowledge Could Help Leafy Amaranth Farmers in East Africa
By Esther Lugwana Nampeera, Ph.D.
Leafy amaranth (Amaranthus) is an important vegetable for people with limited resources in East Africa and contributes to farmers’ livelihoods and food security. Over the past decade, the environmental adaptability and nutritional value of leafy amaranth has helped to increase commercial production and household consumption. Both the leaves and grains of amaranth species are consumed, and most are adapted to grow worldwide. In Sub-Saharan Africa, growing and consuming leafy amaranth has a positive impact on small-landholder farmers. Leafy amaranth has low production costs, is easily cultivated, requires low labor input, and needs only short growing seasons (harvesting can occur 45 days after seeding).
Much about pest biology and pest management practices to control pests of leafy amaranth was unknown, so scientists conducted interviews and focus groups with farmers in Kenya. In a new study published this month in the Journal of Integrated Pest Management, scientists present the knowledge gaps of farmers to show the need for training and innovation.
Six hundred leafy amaranth farmers from four counties (Kiambu, Kisii, Kisumu, and Vihiga) in Kenya were part of individual survey interviews and focus group discussions. The majority (71%) of survey respondents grew leafy amaranth on less than 0.25 acres (<0.1 ha) and vegetable production was regarded as a predominately female occupation with 59 percent female respondents. These small-landholder farmers indicated that insect pests were the major constraint of amaranth production. Of the farmers that reported insect pests as a constraint, 87 percent stated that aphids were the main field pest, ranking as the top insect pest of leafy amaranth in all four counties. Survey respondents were able to identify major aphid symptoms on leafy amaranth as curling of leaves and stunted growth that resulted in low yield and unsaleable leaves.
Forty-two percent of all leafy amaranth farmers managed aphids with some form of insecticide, with 34 percent using synthetic insecticides and 8 percent using non-synthetic methods. In many African countries where amaranth is grown, integrated pest management (IPM) was not employed. Most leafy amaranth farmers relied on insecticides to control pests, and inappropriate use of insecticides on other crops has led to insecticide resistance, residues, pest resurgence, secondary pest infestations, applicator safety, and consumer health concerns. A key informant stated, “Some small-landholder farmers use insecticides without knowing their chemical names; farmers use unacceptable insecticides, frequencies, and application rates that decrease farmers’ safety and increase consumers’ risks.” It was clear that farmers were not able to rate insecticide treatment as being as effective as preventing loss due to insect feeding.
Researchers showed that educational programs and training farmers about IPM in leafy amaranth production are needed. More field research is needed to determine successful IPM strategies for managing aphids on leafy amaranth, which may include biocontrol agents, host-plant resistance, and a variety of cultural methods to reduce pest pressure. Insect infestation causes low yields and poor quality in amaranth crops, so by improving IPM would help to reduce insecticide use and improve sustainability and nutritional food security for small-landholder farmers and consumers.
Journal of Integrated Pest Management
Esther Lugwana Nampeera is a Ph.D. student of Plant Health Science and Management at Jomo Kenyatta University of Agriculture and Technology, JKUAT, Nairobi, Kenya. Esther is also a research scientist at the National Agricultural Research Organization in Uganda. During her Ph.D. study, she was a research scholar at Iowa State University, Ames, Iowa, in the Departments of Horticulture and Entomology.