A survey of some insect pests of cultivated vegetables in three selected irrigation areas along Jakara River, Kano, Nigeria

Abstract

The survey aimed at identifying insect pests that attack vegetables grown in three irrigation areas along Jakara River in Kano, Nigeria. The areas were Kwarin gogau, Nomansland and Kwakwaci. Two methods of trapping the insects were employed, namely hand capture for wingless insects as well as hand net for flying insects. Morphological identification of insects was done using taxonomic keys, hand lens as well as light microscope for checking fine structures. Quadrant was used to determine the frequency of occurrence of insect pest on different vegetable plants at different sites, which was used in computing insect pest density. Six vegetable types were found to be predominantly cultivated in the irrigation sites. These included Lactuca sativa (Lettuce), Brassica oleracea (Cabbage), Amaranthus spp (Spinach), Lycopersicum esculentum (Tomato), Abelmoschus esculentus (Okra), and Allium cepa (Onion). The highest insect pest density of 66.7 pest/m 2 was obtained at Kwakwachi area, where Aphid was found only in that site. Caterpillar (Lepidoptera) and Leaf beetles (Coleoptera) were the only pests found in all the three irrigation sampling sites, while Bug (Hemiptera), Aphid (Homoptera) and Thrips (Thysanoptera) were found at Kwakwaci irrigation site. Amaranthus (spinach) was found to be attacked by all the insect pests identified (which include representatives from seven orders), with exception of Thrips (Thysanoptera). There was significant difference between number of insects per sites (P<0.05). There was also significant difference between average frequencies of insect pest per sites (P< 0.05).

Evolution spatiale et temporelle des dégâts du jasside <i>Jacobiella facialis</i> Jacobi, 1912 (Cicadellidae) en comparaison avec la distribution de la pluviométrie au cours des vingt dernières années dans les zones de culture cotonnière en Côte d’Ivoire

“…Le recours presqu'exclusif aux produits chimiques par les producteurs pour lutter contre les ravageurs pourrait entraîner une modification de l'entomofaune à travers l'élimination des ennemis naturels de certains ravageurs (Imam et al, 2010 ;Gopal et Tarikul, 2014). De plus, il est à signaler, par ailleurs, que pendant des décennies, les stratégies de protection ont essentiellement été dirigées contre les chenilles de la capsule qui sont les principales responsables des pertes de récoltes (Martin et al, 2000 ;Ochou et al, 2012).…”

A Survey of Some Insect Pests of Cultivated Vegetables in Ajiwa Irrigation Site of Katsina State, Nigeria

“…Methods of Imam et al (2010) were followed for sample collection. The sampling site was divided into four quadrates and five plants were selected within the square meter at random from each part.…”

“…Several insect pest surveys have been conducted in different parts of Nigeria (Oparaocha and Okigbo, 2003;Imam et al, 2010;Okunlola and Ofuya, 2010;Aderolu et al, 2013;Olaniran et al, 2014). However, information on the type of insect pests infesting vegetable grown at Ajiwa irrigation site of Katsina State, Nigeria is scarce.…”

“…Some insects are restricted to a limited number of host plants especially the leafy types like lettuce, cabbage and spinach. These insects are called monophagous (Imam et al, 2010).…”

“…Pests cause a lot of damage on crops including vegetables which reduce the quality and/or quantity of yield (Imam et al, 2010).…”