Population Ecology of Aphid Pests Infesting Potato

Abstract

Potato is one of the most important food crops contributing to nutritional and food security in the world. It is grown as a summer crop in temperate areas of the world and as a winter crop in the subtropics of India and China. Potato crop is damaged by numerous pests and diseases of which aphid transmitted viruses are the major concern for healthy seed potato production. Since potato is a vegetatively propagated crop, the viral diseases lead to an ongoing decline in health of the propagating material i.e., seed degeneration. Hence, the management of aphids and aphid transmitted viruses is the first and foremost requirement for seed potato production. Potatoes are infested by a large number of aphid species very few of them actually able to colonise the crop. Most of the aphids are non-specific to the crop and are cosmopolitan and polyphagous. The common colonising aphid species are Myzus persicae, Macrosiphum euphorbiae, Aulcorthum solani, Aphis gossypii, A. fabae, A. spiraecola etc.; while as more than 100 species of aphids are reported to transiently visit potato crop. Of these, more than 65 species are known to transmit one or more potato viruses. Aphids because of their cyclic parthenogenesis and short life cycle can assume epic proportions while on the other hand, their host selection and feeding behaviour predisposes them to being the most effective virus vectors. The host rang and life cycle characteristics of aphids are also key in determining the rate of spread of the viruses. Keeping in view the importance of life cycle variation and population ecology of aphids for virus transmission in potato crop, information is compiled and analysed to identify the gaps in knowledge and help determine the direction of future research, with special emphasis on the subtropics.