Variation in nutrient status of susceptible and resistant bitter gourd varieties infected by root knot nematode, Meloidogyne incognita

Abstract

Seventeen bitter gourd genotypes/ seeds were collected and screened under greenhouse condition for both susceptibility and biochemical reactions to root-knot nematode (RKN) Meloidogyne incognita. Only one variety was resistant with 7-10 number of galls per plants while others were moderately resistant to highly susceptible with > 10 numbers of galls per plants. In order to understand the basis of nematode resistance six varieties namely Sundargarh local-1, Amatalla Beejghar Karala long green, Ankur hybrid (Moderately resistant) and Nakhara local, Indojapane hybrid, Rajsunakhala local-1 (Highly susceptible) were sown in earthen pots in the greenhouse maintaining four replications in Completely Randomized Design. This experiment was terminated at 45 days after sowing of seeds or 30 days after inoculation of nematodes. The Nitrogen content (%) in shoot was significantly lower by 11.92-69.34 in the resistant varieties as compared to that of susceptible variety but increased by 5.94% in root system of resistant variety in contrast to susceptible one (37.07%). The crude protein of the infected shoot decreased in the similar trend like nitrogen content of the infected shoot. The infected plants had decreased percent of phosphorus content in shoots of highly susceptible and moderately resistant varieties except Sundargarh local-1 with increased percent of phosphorus content in roots. Significant increase of potassium content of both susceptible and resistant infected plants which increase was more pronounced in both shoots and roots of resistant varieties as compared to the susceptible varieties. In shoot and root the micronutrients were observed decrease percentage in Zinc by 19.00-21.76 and 9.53-23.93, Iron by 3.11-4.1 and 14.35-33.85, Copper by 5.91-48.04 and 15.10-25.08 respectively, except Manganese by 4.10-18.5 in shoot and an increase trend of percentage of 6.35 to a decrease trend of 41.02percent in infected plants over control in varieties of bitter gourd.