Diversity of Insects of Two Rice (Oryza sativa L. 1787) Farms in Nnamdi Azikiwe University, Awka, Nigeria

Abstract

The recognition of insect-related damages to rice plants and the subsequent consequences for biodiversity have shown the relevance of insect communities in rice farms. This study documented the insect fauna of rice (Oryza sativa L. 1787) in two rice farms in Nnamdi Azikiwe University, Awka, Nigeria from September to November, 2022. The insects associated with the two sites were collected using handpicking, sweep net, water trap and pitfall trap methods. Data collected from the study were subjected to non-parametric t- test at 5% significant level. A total of 51,021 insects belonging to twelve insect orders were found associated with the two sites. Out of the aforementioned number, 15,120 (29.63%) were collected from site 1 while 35,901 (70.37%) were collected in site 2. There was significant difference (P <0.05) on insect abundance between site 1 and 2. Crematogaster peringueyi was found to be the most abundant (82.67%) insect in site 1, whereas Camponotus perrisi was found to be the most abundant (27.85%) in site 2. The result further showed that only Hobomok skipper had the least relative abundance (0.01%) in site 1, while Catantops quadratu, Anacatantops notatus, Dysdercus cingulatus, Crematogaster peringueyi, Dasyleurotettix infaustus and Apis mellifera had the least relative abundance (0.01%) in site 2. The diversity indices computed showed that Site 1 had a higher Simpson dominance index (0.6845), Shannon Weiner diversity index (1.07597) and Shannon Weiner evenness  than site 2 (0.0019, 0.41248and 0.0393 respectively). The Margalef richness index (6.3879) of site 2 was greater than site 1 (4.9876).There is need for regular monitoring of insects in rice farms for sustainable management of the crop.