Pathogenicity of Lance Nematode, Hoplolaimus seinhorsti on Red Sanders, Pterocarpus santalinus Tree Seedlings

A pot culture experiment was conducted in a glass house to assess the pathogenicity of Hoplolaimus seinhorsti on Red Sanders, Pterocarpus santalinus in 25 × 15 cm bags filled up with steam sterilized fine river-sand mixed with red earth at the ratio of 3: 1. The freshly collected seeds were presoaked continuously in normal water by changing water daily for eight days for presowing treatment. Fifteen days after germination, the plants were infested with adults and juvenile of H. seinhorsti, of the treated seeds at the rate of 0, 100, 200, 400 and 600 larvae pot-l around the root zone. The results revealed progressive reduction in length and weight of shoot and root significantly with the increase in the level of initial inoculum. The multiplication rate of H. seinhorsti was 9.3 to 100 larvae kg/soil. There was no reduction in chlorophyll contents to 100 larvae kg/soil, but significant reduction was recorded in 600 larvae kg/soil (13.2). The stomatal conductance, transpiration rate and net photosynthetic rate were significantly reduced, when the nematode population level exceeded 200 kg/soil.