Deciphering host plant resistance mechanisms of rice genotypes resistant against Brown Planthopper

Antixenosis and antibiosis response of brown planthopper (BPH), Nilaparvata lugens (Stål) (Hemiptera: Delphacidae) and tolerance response of ARC 10,894 and ARC 7229 genotypes in comparison to other resistant genotypes were assessed under greenhouse conditions. In comparison to the susceptible check TN1, significantly less number of nymphs settled on rice genotypes CR2711 (59.07%), ARC 10,894 (58.29%), PTB33 (58.3%), and ISM38 (57.52%). In comparison to the susceptible check TN1, the adult males and females also settled in less number on PTB33, CR2711, ARC 10,894, ISM38, IRGC104646 and CR3006-8-2. The number of feeding marks on the genotypes was in the order of CR2711 (16.67) > Ptb33 (15.83) > , ISM38 (15.83) > , IRGC104646 (15.33) > , ARC 10,894 (15.33) > , CR3006-8–2 (15.17) > , ARC 7229 (12.67) > TN1 (6.67) and the order was exactly reverse for the fecundity. The results of the seed box scoring study revealed CR2711, ISM38, IRGC104646, CR3006-8-2, ARC 10,894, ARC 7229 and Ptb33 genotypes to be resistant to BPH with significantly low damage scores (1.30–3.07). Further, significantly lower honeydew excretion area (31.58–43.97 mm2); nymphal survival (51.6–63.98%) and growth index (2.44–3.62) were recorded in resistant genotypes than TN1. Biochemical analysis of test genotypes with and without BPH infestation revealed variations in catalase, peroxidase, and soluble phenolics. Besides, a negative relationship between each of these biochemical constituents and honeydew excretion, nymphal emergence, growth index, and nymphal survival apiece was observed. A tolerance study revealed ARC 10,894, ARC 7229 and other resistant genotypes as more tolerant than TN1. The genotypes ARC10894 and ARC7229 were identified by the study as new BPH resistance sources that can be utilised in resistance breeding.