ASSESSMENT OF NEMATODE DIVERSITY IN SELECTED AGRICULTURAL FARMLANDS AT SCIENCE VILLAGE, NNAMDI AZIKIWE UNIVERSITY, AWKA

Nematodes are essential yet often underappreciated components of agricultural ecosystems, influencing crop yields and soil health in diverse ways. This study investigates nematode diversity across selected agricultural sites at Nnamdi Azikiwe University, Awka, focusing on two rice farms, two maize farms, and two cassava farms, with a forest control site for comparison. Utilizing a soil auger and sucrose centrifugal extraction method, 250 nematodes were identified, with an average of 35.14±3.74 per site. The forest site exhibited the highest mean abundance (47±0.0), while the cassava farm had the lowest (23.5±5.5). Statistical analysis revealed significant differences in nematode abundance (F=10.4, P=0.02). The maize farm showed the highest diversity index (0.9±0.2) and evenness (1.00±0.00), while the rice farm displayed the lowest diversity index (0.64±0.32) and evenness (0.66±0.21). The forest control site had a greater diversity index (1.80±0.0) and evenness (1.01±0.00) than agricultural sites, although these differences were not statistically significant. Five nematode feeding categories were identified, with sedentary endoparasites being prevalent across all farms and other categories showing site-specific occurrences. The study underscores the importance of sustainable agricultural practices, such as crop rotation and reduced monoculture reliance, to promote nematode diversity and enhance soil health.