ABSTRACT

The survey was carried out in four districts namely, Dharwad, Belagavi, Haveri and Gadag and studies on screening of sorghum genotypes against fall armyworm, Spodoptera frugiperda (J E Smith) in rabi sorghum and evaluation of push pull components was conducted at AICRP Sorghum, MARS, Dharwad during rabi 2023-24. Among four districts, Belagavi exhibited higher per cent plant infestation (42.83 %), leaf damage ratings (2.53) and egg mass (0.12). On the other hand, lower leaf damage severity rating (1.85) and egg mass (0.01) were found in Haveri district. While the lowest per cent pest infestation was recorded in Gadag district (15.98 %).
Out of 33 genotypes screened against FAW, genotypes SPV-2217 and SPV-2832 were found to be promising and categorised as resistant genotypes however, genotypes CSH-16 and C-43 were found to be susceptible by recording highest leaf damage score. Correlation of various biophysical parameters with leaf damage score viz., glossiness (r= -0.248**), seedling vigour (r= -0.295*), trichome density (r= -0.785*), leaf thickness (r= -0.517**), leaf length (r= -0.294**) and leaf width (r= -0.602*) exhibited negative correlation. Similarly, correlation of various biochemical parameters with leaf damage score viz., total phenols (r= -0.161**) and silica (r= -0.249**) exhibited negative correlation while, reducing sugars (r= 0.434*), soluble protein (r= 0.360*) and nitrogen content (r= 0.110**) exhibited positive correlation.
The influence of intercrops and border crops on the incidence of FAW on sorghum recorded lowest egg masses, larval population and leaf damage in sorghum intercropped with french bean and napier grass as border crop and highest egg mass, larval population and leaf damage was noticed in sole sorghum treatment. Maximum yield was recorded in sorghum + french bean + napier grass treatment indicating superiority of the treatment over others with respect to reduction of FAW damage.