Botanicals for the management of phytonematodes

There is a need to exploit the toxic components of promising botanicals specially those, which have shown nematicidal properties viz. Azadirachta indica (Neem), Pongamia glabra (Karanj), Argimone mexicana (Bhatkatai), Datura metel (Dhatura), Eucalyptus globorus (Eucalyptus), Phyllanthus niruri (Jaar Aonla), Madhuca indica (Mahua), Shorea robusta (Sal), Asparagus sprengeri (Asparagus), Crotolaria juncea (Crotolaria), Tagetes spp. (Marigold), Ocimum sanctum (Tulsi), Calotropis procera (Madar), Swertia chiratta (Chiratta), Bauhinia variegata (Kachnar), Semecarpus anacardium (Bhilawa), Cannabis sativa (Bhang), Melia azadirach (Bakain), Embelia ribes (Babadinga), and Psidium guajava (Guava). Neem (Azadirachta indica) is a versatile tree of Indian origin, used for its medicinal and insecticidal properties and as a source of neem oil, fodder, fibre, fertilizer and timber (Narwal et al., 2003). Neem extract was most potent in reducing virus infectivity and nematode populations. Wani and Alam (2000) used several plants as intercrops between the rows of other crops for the control of plant-parasitic nematodes including Tagetes spp., neem (Azadirachta indica), Brassica spp., Crotolaria spp., and Asparagus. These plants when intermixed with other crops caused significant decline in the soil population of nematodes (Nageshwari and Mishra, 2005).