Mites and insects occurring on some leafy ornamentals and floricultural plants in Howrah and Purba Medinipur districts of West Bengal, with their economic importance

Abstract

The present paper deals with a total of 26 species of mites under 10 families, 17 genera and 3 orders as well as 10 species of insects under 5 families, 9 genera and 3 orders, collected from some floricultural and leafy ornamental plants in Howrah and Purba Medinipur districts of West Bengal. It may be mentioned here that these two districts are the largest producers of these plants. Among the mites, there are 14 species under 4 families and 8 genera which belong to phytophagous group, 10 species under 4 families and 7 genera belong to predatory group and remaining 2 species under as many families and genera belong to fungal feeding group. All the species of mites and insects are listed with their respective host/habitat plants, collection localities as well as their economic importance, if any. The most injurious species of mites which were observed in the field are Tetranychus urticae on Dahlia variabilis, Oligonychus biharensis on Rosa centifolia, Eutetranychus orientalis on Tabernaemontana divaricata and, Eotetranychus suginamensis on Nyctanthes arbor-tristis. Among the predatory mites, Amblyseius largoensis and Amblyseius herbicolus are important predators on phytophagous mites and the occurrence of the other predatory mites are only occasional. Among the insects, Ferrisia virgata, Aphis gossypii and Scirothrips sp. on Codiaeum variegatum, and Ferrisia virgata on Hibiscus rosa-sinensis, respectively were found abundantly.