Efficacy of some selected botanicals and broad spectrum pesticides against foliage insect pests of cultivars of potato (Solanum tuberosum L.) in Zoba Anseba, Eritrea

Abstract

Potato is one of the major vegetable crops after tomato and onion in Eritrea. This crop is highly attacked by many insect pests mainly Whiteflies, Aphids and Jassids. In Eritrea, limited research is done before on insect pest of potato hence this study aimed to know the most serious foliar insect pests and to determine the relative efficacy and performance of the common potato cultivars and the selected insecticides respectively. The experiment was conducted at Hamelmalo Agricultural College farm station, Eritrea using three potato cultivars (Picasso, Ajiba and Zafira). The design of the experiment was randomized complete block in triplicate. Besides two broad spectrum pesticides (deltamethrin, dimethoate) and two botanicals; neem seed kernel and tobacco leaf extracts were used. Data on the population count of insect pests before and after each spray were recorded. Whiteflies, aphids, jassids and red spider mites were identified and the result showed the highest aphid population reduction during tobacco leaf extracts spray followed by deltamethrin and neem seed extracts sprays respectively. Nevertheless, there was no significant difference between deltamethrin and neem seed extracts sprays in whitefly reduction and tobacco leaf and neem seed extracts sprays in reducing jassids population. The results further indicated maximum insect pest count in Ajiba and Zafira cultivars while Picasso showed minimum counts which indicate relative tolerance of the cultivar. The correlation analysis indicated, there was no significant association among insect pests and yield ha-1. However, the growth parameters showed significant correlations with yield ha-1 at 0.01% level of significance.