Quantitative assessment and seasonal incidence of soil invertebrates in okra (Abelmoschus esculentus L.) crop

The present study on population dynamics and diversity of soil invertebrates was carried out at Vegetable Research Farm, Punjab Agricultural University, Ludhiana during 2019. The study revealed that okra crop harboured 14 different soil invertebrate species belonging to nine orders and 13 families dominated by order coleoptera (five species) dominated by ground beetles. Interestingly, higher relative abundance (%) was recorded in order hymenoptera (80.72%) followed by polyzoniida (10.41%) among which higher dominance (%) was recorded in little black ants (80.78%). Species richness, species evenness, Shannon-Wiener index (H’) and Simpson’s index were calculated to be 14.0, 0.094, 0.098 and 0.051, respectively, indicating high degree of diversity among soil invertebrates in okra crop. Interestingly, an increase of 88.84 and 69.64% in population was recorded in root-knot and free-living/predatory nematodes at harvest time compared to the okra crop sowing time. A positive correlation (r=+0.06 to + 0.83) was recorded between soil temperature and soil moisture with soil invertebrate population. Okra crop fields survive soil fauna, which is a key factor for increasing soil fertility and productivity and its physical characteristics, which should be increased using soil amendments.