author(s)
Srinivas G and Sushil Kumr

abstract
Comparative insect and mite biodiversity studies were undertaken in organic and conventional Farming Systems (FS) of okra at certified organic farming unit of ASPEE College of Horticulture and Forestry (ACHF) and conventional farm of N. M. College of Agriculture (NMCA), Navsari Agricultural University, Navsari during 2016-2018. Total number of 1669 insect and mite individuals belonging to 10 insect orders and 1 mite order and 25 insect and 2 mite families of 32 species of insects and 2 mite species were recorded at organic okra farm against 1503 individuals belonging to 9 insect orders and 1 mite order and 22 insect and 2 mite families containing 26 insect and 2 mite species at conventional okra farm. The diversity of insect and mites was higher in organic okra farm as compared to conventional okra farm. Higher species richness (34 species), species abundance (1669), species evenness (J=0.81), species richness index (R=4.45) and Shannon diversity index (H=2.87) was observed at organic okra farm against lower species richness (28 species), species abundance (1503), species evenness (J=0.77), species richness index (R=3.69) and Shannon diversity index (H=2.57) in conventional okra farming system. Insect order Hemiptera and mite order Acarina were more represented at conventional farm (53.71 and 15.21%) as compared to organic farm (42.63 and 11.59%). Insects of Coleoptera (14.18 and 7.13%) and Hymenoptera (9.29 and 5.58%) were more abundant at organic farm as compared to conventional farm. Relative abundance of herbivores was higher (85.36%) with lower species evenness (J=0.77), species richness (R=2.24) and Shannon diversity index (H=2.18) at conventional farm as compared to lower relative abundance (72.86%) with higher species evenness (J=0.80), species richness (2.54) and Shannon diversity index (H=2.37) at organic okra farm. Similarly, 426 insect and mite predators comprising of 12 insect predators and 1 predatory mite species were recorded at organic farm as compared to 207 individuals of 8 species of insect predators and 1 predatory mites at conventional okra farm. The relative abundance of predators was higher (25.46%) with higher species evenness (J=0.84), species richness (R=1.99) and Shannon diversity index (1.93) at organic okra farm whereas, lower relative abundance (13.67%) with lower species evenness (J=0.76), species richness (R=1.50) and Shannon diversity index (H=1.84) were recorded at conventional okra farm. In the present investigation, no parasitoids were observed in both the farming systems. Species abundance and relative abundance of pollinators was also higher in organic okra as compared to conventional okra farming system. Higher abundance (39), relative abundance (1.68%), species evenness (J=0.93), species richness (R=0.31) and Shannon diversity index (H=0.63) were observed at organic okra farm as compared to lower abundance (28), relative abundance (0.97%), lower species evenness (J=0.81), species richness (R=0.27) and Shannon diversity index (H=0.54) of pollinators in conventional okra farming system. The lower Shannon diversity values indicate very low pollinator diversity in both organic and conventional okra farming systems.