Pest management challenges for smallholder vegetable farmers in Zimbabwe

Smallholder vegetable production is expanding rapidly in Zimbabwe both for local sale in urban markets and for export. Pest management practices of 12 small-scale vegetable farmers in two areas of Zimbabwe were surveyed over a five-month period to gather information on crops, pests, diseases and cro p protection methods. A range of serious pests and diseases affects non-ind igenous vegetables such as Brassicas, tomatoes, onions and cucurbits. Altho ugh farmers use some cultural control methods and occasionally botanical pe sticides, pest control is predominantly by the use of conventional syntheti c pesticides. These are usually applied through lever operated knapsack spr ayers although some less orthodox application methods are occasionally used . Results are variable and there are concerns about risks to sprayer operat ors, consumers and the environment (including natural enemies) due to short comings in protective clothing, large deviations from recommended doses and excessive run-off to the soil. Field trials were carried out to evaluate a modified sprayer lance which directs the spray upwards rather than downwar ds in an attempt to place more of the spray under the leaves where most of the arthropod pests are found. The 'V lance' as it is called improved the u niformity of spray coverage on the upper and lower leaf surfaces and is exp ected to improve efficacy of spraying and/or offer the opportunity to reduc e doses or spray frequencies. Farmers who tested the device reported good r esults and gave constructive feedback for future improvements. The smallhol der vegetable sector requires support in the form of improved access to exi sting pest management information (in an appropriate form) and focused rese arch targeted at the knowledge gaps which currently impede implementation o f sustainable IPM. (C) 2000 Elsevier Science Ltd. All rights reserved.