Department of Entomology, G. B. Pant University of Agriculture and Technology, Pantnagar, Distt. Nainital-263145
Studies on growth and development on 28 ornamental plant species revealed that larvae of Diacrisia obliqua were unable to complete the development on 21 plant species. Larvae were able to survive and develop on Chrysanthemum leucanthemum, Dahlia spp., Euphorbia splendens, Griselinia lucida, Meyenia erecta, Mimosa pudica and Zinnia elegans. Significant difference was observed in larval survial, larval period, per cent pupation, pupal weight and adult emergence. Females from Mimosa pudica did not lay eggs. When Griselinia lucida was fed to larvae adults laid few infertile eggs. Maximum number of eggs were laid by females from Dahlia spp. The highest number of eggs hatched in Zinnia elegans. Computation of growth index showed Meyenia erecta and Mimosa pudica poor host plants while Dahlia spp. and Zinnia elegans the superior ones for the development of this insect. Both Mahalanobis D2 statistics and Canonical variate analysis indicated six clustrers having G. lucida and Z. elegans in one cluster while all other plant species in different cluster. Contribution of different growth parameters in creating diversity among ornamental plants revealed that larval period contributed most followed by pupal weight, pupal period and per cent pupation.
