Plant-parasitic nematodes (PPNs) such as Meloidogyne incognita are a serious threat to many crops and causes substantial reduction in productivity. We evaluated the nematotoxic effects of aqueous leachates prepared from Azadirachta indica A. Juss. and Cymbopogon citratus DC. at 6-concentrations (10,20,40,60,80 and 100 %) against second stage Juveniles (J2) of M. incognita. Laboratory bioassays were done to estimate the impact of leachate concentrations against J2 mortality at 24, 48 and 72 h. Results demonstrated concentration and time dependent mortality responses. The 100 % neem leachate exhibited the highest nematicidal activity after 72 h, resulting in complete mortality (100 ± 9.1), similarly, 80 % lemongrass leachate achieved 99 ± 0.9 % mortality at 24 h. In addition to this, GC-MS profiling of both the leachates were performed to identify bioactive compounds potentially responsible for the nematicidal activity. These leachates showed the presence of 2-propyl-1-pentanol, phytol acetate, phytol and squalene at > 90 % similarity index. Overall, neem and lemongrass leachates exhibited 90 % nematicidal activity at higher concentrations and longer exposures, underscoring their potential as biorational alternatives to synthetic nematicides. Given their wide availability, low cost and environmental safety, these botanicals can be effectively integrated into sustainable PPNs management strategies to combat M. incognita in agricultural systems
DEEPIKA et al. (Wed,) studied this question.