Species Richness of Leaf Roller and Stem Borers (Lepidoptera) Associated with Different Paddy Growth and First Documentation of Its DNA Barcode

Abstract

Leaf folder and stem borer are pest moths (Lepidoptera) of paddy crop and caused serious damage and significant rice yield loss. The richness, abundance, and diversity of the pest moths were calculated in one paddy planting season and sampled from a model conventional paddy field, located on the west coast of Peninsular Malaysia (Sabak Bernam, Selangor). The adult and immature stages of moths associated with paddy plants have been sampled using active sampling namely sweep net and stem cross-cutting. A total of 189 individuals belonging to five species under two families (Crambidae and Noctuidae) were recorded. Overall, the richness (R’), diversity (H’), and evenness (E’) index of lepidopteran species were 0.76, 1.51, and 0.90, respectively. The richness and species abundance throughout the paddy stages were discussed. The DNA barcode of five collected species using cytochrome oxidase subunit 1 (CO1) viz. Cnaphalocrocis medinalis (Guenée) (leaf folder), Scirpophaga incertulas (Walker), Chilo auricilius Dudgeon, Sesamia inferens (Walker), and Parapoynx stagnalis (Zeller) (stem borers) were presented. This study’s outcomes are very important as the initial stage for conservation purposes, especially in managing the strategy in handling the pest species populations in the paddy field.