Evaluating Hymenopteran Parasitoid Communities Across Varied Organic Rice Cultivation Practices
M. Chaitanya *
Department of Entomology, Professor Jayashankar Telangana State Agricultural University, Rajendranagar, Hyderabad– 500030, India.
K. R. Mahendra
Department of Entomology, Professor Jayashankar Telangana State Agricultural University, Rajendranagar, Hyderabad– 500030, India.
G. Anitha
AICRP on Biological Control of Crop Pests and Diseases, Rajendranagar, Hyderabad– 500030, India.
*Author to whom correspondence should be addressed.
Abstract
The abundance and biodiversity of parasitoids are important parameters in organic rice's natural regulation of insect pests. The present study was carried out in the fields of the Indian Institute of Rice Research, Rajendranagar in rabi 2020 to know the impact of various treatments (Trichoderma, Pseudomonas, farmer’s practice, organic rice without seed treatments, and untreated control) on the abundance and diversity of Hymenopteran parasitoids. Various methods such as visual count, sweep net, yellow pan traps, and yellow sticky traps were used to collect the parasitoids at 30,45, 60, 90, and 120 DAT of rice across all the treatments. It was revealed that a count of total 12,573 parasitoids collected, the contribution of Eulophidae was higher (64.33 percent) followed by Scelionidae (13.92 percent) and Trichogrammatidae (11.38 percent). Pseudomonas treatment supported the higher abundance (25%) and density of parasitoids (3.81 per sq. m) while Trichoderma recorded a higher diversity of parasitoids with the highest Shannon - Wiener diversity index (H´= 1.11) and lower Simpson diversity index (D= 0.46). Yellow sticky traps and yellow pan traps were found as effective methods for the collection of Hymenopteran parasitoids. The higher abundance and diversity of parasitoids in organic treatments indicated the impact of organic amendments and bioagents in supporting the biodiversity of the rice ecosystem.
Keywords: Parasitoids, Trichoderma, Pseudomonas, organic rice, diversity indices