Diversity of Pteromalids (Pteromalidae: Hymenoptera) among three Rice growing zones of Tamil Nadu, India

Abstract

Surveys were conducted to explore the Pteromalid fauna in rice ecosystems of Tamil Nadu in three different rice growing zones viz., Western zone, Cauvery delta zone and high rainfall zone. The study recorded a total of 82 individuals that represents 2 subfamilies, 6 genera and 13 species. Alpha and beta diversity were computed for three zones and the diversity indices (Simpson's index, Shannon-Wiener index, Pielou's index) revealed high rainfall zone as the most diverse zone, while Cauvery delta zone being the least diverse. However, 32 out of 82 individuals were collected from Western zone and thus ranks first in species abundance. Trichomalopsis thekkadiensis was the dominant pteromalid species in the rice ecosystem with a relative abundance of 23.1%. Comparison of species similarities between the zones, revealed 45%, similarity between Western zone and high rainfall zone; 33% similarity between Cauvery delta zone and high rainfall zone and 27% between Western zone and Cauvery delta zone.