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of the cells. (Sundararaju and Mwhata, 1992). In addition, reduced growth is noticed due to

the decreases in plants root and shoots weight (Panday et al., 1992; Haseeb et al., 1993). Loss
of root efficiency and part of the consequent reduction of growth and yield can be accounted

for reduction and deformation of the root system. The nutritional stress thus imposed on the
host during pathogenesis is overcome through changes in the biochemical constituents of the

infected tissues.

Sugar depletion was observed in the infected plants (Mohan and Dhawan, 2000;

Vaithesswaran and Mohamed Ibrahim, 2003). Metabolic leakage of carbohydrate during the
post-infection period, particularly in the early gall stage may be the possible reason for sugar

reduction in diseased plants (Rashid et al., 1985). The major sources of energy derived from
the host are the stored carbohydrate which is converted into utilizable from by the action of

hydrolytic enzymes secreted by the nematodes (Singh et al., 1978).

The decreased starch was observed in the host plant infected by Meloidogyne spp.

(Sharma et al., 1996; Vaithesswaran et al., 2006). The reduction in chlorophyll pigments and
total content of chlorophyll in root-knot nematode infected plants were noticed by various

studies (Mohanty et al., 1997; Abbasi et al., 2008).

MATERIAL AND METHOD

Preparation of sand soil mixture
River soil, Garden soil and Red soil mixed in the ratio 3:1:1 were selected for the

rearing of plants in the laboratory. This mixture was meshed to remove the coarse particles.
The sand and soil mixture were sterilized in an autoclave at 15 lbs, pressure for 2 hours (Fred

and Wakesman, 1928) to destroy various bacterial and pathogenic organism present in it.

Seedling culture
The seeds of Solanum melongena were surface sterilized with 0.1% mercuric chloride

solution and rinsed for 5 minutes in sterile water 6 times before sowing. Five seeds were

sown in sterilized pots containing 1.5 kg sterilized sand- soil mixture. Seven days after
germination, the seedling was thinned to one plant per pot, ensuring they were all of uniform

growth and vigour. The seedling was allowed to grow up to2 leaves and a bud stage. After

this, they were ready for inoculation.

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