Soil insect pests of crops grown by subsistence farmers in Malawi

Smallholder farmers in southern Malawi cropping systems are dominated by maize, either as a mono crop or interplanted with other crops, principally legumes. The crops are damaged by a wide range of soil insect pests where the damaging stage of their life cycle lives in the soil, within the crop or below ground level and they can damage crops from sowing to harvesting. Soil insects are more cryptic and the damage they cause is poorly appreciated by farmers and other extension workers.<br /><br />A survey of soil insect pests in smallholder farms was conducted to establish the status of the pest nationally in order to develop realistic pest management strategies for the farmers. The Ecological Planning Areas (EPAs) were selected within the three Agricultural Development Divisions (ADD) &ndash; Machinga, Blantyre and Shire Valley.<br /><br />The study found that:<br /> maize: damage was manifested by attacks on the roots, leading in some cases to upward penetration of the stem, or direct cutting of the stem. The highest incident of damage was caused by termites sorghum: damage was manifested by attack on the root system. Termites were the only pest recorded phaseolus beans: the only pests causing damage Alcidodes ssp, Ophiomyia ssp, and termites cowpeas: Alcidodes ssp, Hilda ssp and termites were the only pests with an overall incidence pigeonpeas: termites were the only pest with an overall incidence groundnuts: whitegrubs, termites, Gonocephalum ssp, wireworms, schizonycha and Hilda ssp cotton: termites were the only pests with an overall incidence.<br /><br />The authors conclude that it is important to continue these surveys to establish the status of the pest nationally in order to develop realistic pest management strategies particularly for small holder farmers and that this requires adequate financial and material support from donors, private sector and government.