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Subject: Entomology × Author: Manimala, Rayapureddi Naveena × End date: 2021 × Start date: 2021 × Type: Thesis ×
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    ThesisItemOpen Access
    Studies on diversity and abundance of predatory Coccinellids in different crop ecosystems at Pantnagar
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Manimala, Rayapureddi Naveena; Agnihotri, Meena
    The present investigation was carried out during November, 2020 - April, 2021 at six different locations and laboratory studies were conducted at Pulse Entomology Laboratory, Department of Entomology, Govind Ballabh Pant University of Agriculture & Technology, Pantnagar. Diversity of predatory coccinellid beetles was studied in 32 crops including field crops, vegetable, fruit and ornamental crops. Eleven species of predatory coccinellid beetles were recorded. Among all the species, ten species were recorded under the subfamily coccinellinae and the one species belonged to subfamily chilocorinae. Among all these crops, maximum number (six) of species of coccinellids were observed in rose and chrysanthemum and the minimum number (one) of species were observed in chilli, cabbage, gerbera and dahlia. Seasonal abundance of coccinellid species in different crops revealed that three species C. septumpunctata, C. sexmaculata and C. transversalis were found active throughout the study period. The peak population (1.1/m2) of H. dimidiata during 7th SW, C. transversalis (7.1/m2) during 11th SW, C. septempunctata (47.5/m2) and P. dissecta (3.1/m2) during 12th SW, I. koebelei (0.4/m2) and H. variegate (0.2/m2) during 15th SW, C. sexmaculata (30.5/m2), M. discolor (4.5/m2) and M. univittata (2.6/m2) during 50th SW while B. suturalis (2.4/m2) and A. cardoni (0.2/m2) during 52th SW. Present study showed that these predatory coccinellid species were well acclimatized with all the weather conditions at pantnagar, however population of coccinellids was different in various crops and this knowledge could be helpful for the utilization of these beetles in biological control program. Olfactory response of predatory coccinellid beetles towards aphids and their host plants revealed that an increased number of coccinellid beetles were observed when host plants were added with aphids. C. septempunctata showed a higher response (30%) towards R. Maidis infested wheat, L. erysimi infested mustard and M. rosae infested rose, C. sexmaculata showed a higher response (40%) towards R. maidis infested wheat and C. transversalis showed a higher response (35%) towards M. rosae infested rose. Present study revealed that the tested crops could be utilized as trap crops aside the major crops to attract the predatory coccinellid beetles.