THE EFFECT OF ZINC ON WHITE-BACKED PLANTHOPPER INFESTATION, RICE PLANT BIOCHEMICAL RESPONSES CROP YIELD, AND INSIGHTS FOR SUSTAINABLE PEST MANAGEMENT

The white-backed planthopper (WBPH), Sogatella furcifera, has emerged as a highly destructive rice crop pest, leading to significant annual yield losses. Excessive zinc (Zn) can be detrimental to plants, but the role of Zn on herbivorous insects remains uncertain. In this research, we conducted a pot culture experiment in the Kharif season 2017 at the Department of Entomology, College of Agriculture, OUAT, Bhubaneswar, Odisha, India. The aim was to investigate the effect of Zn (in the form of Zn EDTA or ZnSO4) when applied as a basal or foliar spray, either alone or in various combinations, on the WBPH. Our findings revealed that the population of WBPH in the control group of rice plants was at its highest (79.20) at 60 days after transplanting (DAT) compared to the groups treated with Zn. Further, an analysis of 60-day-old plant samples showed that applying Zn increased levels of chlorophyll, phenols, and soluble protein content. In addition, there was an elevation in the activity of superoxide dismutase (SOD), peroxidase (POD), and phenylalanine ammonia-lyase (PAL). Simultaneously, this treatment decreased the levels of total free amino acids, total soluble sugars, and proline content. Both increase and decrease in respective biochemical parameters were indicators of an induced antibiosis mechanism in rice plants against the WBPH. The correlation analysis between the WBPH population and various plant biochemical parameters showed that the WBPH population was inversely correlated with total chlorophyll, phenol, soluble protein content, as well as the activities of SOD, POD, and PAL. Conversely, it positively correlated with total free amino acids, soluble sugars, and proline content. Therefore, this research has provided valuable insights into the presence of Zn, which significantly influences the population of WBPH, suggesting a potential avenue for WBPH control and rice yield improvement through strategic Zn application.. KEYWORDS :Antibiosis, Biochemical parameters, Enzymes, Rice, Zinc