Aphid-associated phytochemicals and regulating enzymes in Brassica juncea (L.) Czern and Coss cultivars vis-a-vis host selection and bionomics of Lipaphis erysimi (Kaltenbach)

The current investigation uncovered notable variation in the host selection and bionomics of Lipaphis erysimi, alongside the induced levels of various phytochemicals in Brassica juncea cultivars. The mean generation and doubling time were significantly longer, while host preference, intrinsic and finite rates of increase, and gross and net reproductive rates were lower (P < 0.001) on Pusa Mustard 27, RLC 3, NRCHB 101, DRMR 150-35, Pusa Mustard 26 and Pusa Mustard 25. The cultivars viz., NRCHB 101, Pusa Mustard 25, Pusa Vijay, DRMR 150-35, RLC 3, DRMRIJ 16-38, Pusa Mustard 27, Pusa Double Zero Mustard 31 and Pusa Mustard 30 and RH 725 showed significantly greater variations in the phytochemical and enzymatic profiles, exerting greater deleterious effects on the life history parameters of L. erysimi. Regression analysis revealed that the induced amounts of total sugars, FRAP, total glucosinolates, AO, catalase and PAL contribute to 40.11 to 80.15% variation in bud preference and bionomics. Path analysis indicated a direct negative effect of total proteins, sugars, phenols, antioxidants, FRAP, glucosinolates, chlorophyll A, total chlorophyll, APX, PAL and myrosinase on the host selection and bionomics of L. erysimi, and can be used as biochemical markers for identifying aphid resistant B. juncea cultivars. Furthermore, DRMR 150-35, NRCHB 101, RLC 3, Pusa Mustard 26, RH 749 and Pusa Mustard 27 demonstrated elevated levels of induced defence compounds, leading to pronounced negative effects on the host selection and bionomics of L. erysimi, hence can be used in Brassica improvement programme.