Studies on the Resistance in Eggplant (Solanum Melongena) and Influence of Salinity on Infectivity and Development of M. Javanica

Abstract

Root-knot nematode Meloidogyne spp. and cyst nematodes Heterodera spp. are major nematode problems in crop production, particular under tropical weather condition. Because of their economic importance in the country, studies were carried out on the culturing of Meloidogyne javanica (Kofoid & white, 1919) Chitwood, 1949 and Hetereodera zeae KOSHY, Swarup & Sethi, 1971, to screen out resistance in different varieties of brinjal and of corn. A number of media i.e., Murashige & Skoog, 1962. linsmaier & Skoog. 1965, Gamborg’s B-5, 1976, were tested for the development of pure cultures of M. javanica on brinjal in which linsmaier & Skoog,1965 medium was found best for shoot development and Gamborg’s B-5 MEDIUM (WITHOUT AUXIN AND CYTOKININ) proved best for root culture. These two media were therefore used for further studies. Five cultivars of brinja viz. Sarhandi long, Qiaser, Neelum, and 13 cultivars of corn viz., Faisal, Bihar, Afrat, Sunheri, EHSAN, sultan, Sarhad white, Akber, Sarhad yellow, Neelum, Shaheen, Agaiti 72, Azam, Gauher and Composite 15were evauled for resistance studies of M. javanica on brinjal in vitro and Heterodera zeae on corn in green house. Almost of all brinjal cultivars tested were found susceptible to M. javanica infection with varying degree of infection but cv. Multan selection was found partially resistant. Brinjal seeds were surface sterilized with 2-5% of corn with 5-20% NaoCL. sterilized seeds were laced for germination on 1.8% water agar and incubated at 25-300C. Egg masses of M. javanica were surface satirized with 0.1% mercuric chloride. Temperature ranging 2-300c was found suitable for the growth of brinjal roots and development of M. javanica. All the corn cultivators used to screen resistance alienists corn cyst nematode Heterodera zeae under green use condition were found susceptible at varying degree to H. zeae. No cultivator except Sarhad white was found resistant to this nematode. Studies showed that Heterodera zeae require 18-20 days to complete its life cycle rom second stage juvenile to second shade juvenile on susceptible corn cultivars under field condition Influence of different concentrations of NaCl, CaCL2h2O alone and in combination were studied on the hatchability and invitro infectivity of Meloidogyne javanica juvenilise on tomato. Juvenile hatching and infectivity were found inversely proportional to the salt concentration Effect of different concentration of CaCL2¬ and NaCL and third combination was studied on five tomato cultivars viz Roma VF, Roforto, Lyallpur selection, PARC 1 and PARC 2. salts at higher concentration in vitro and in green house studied suppressed penetration of roots of juveniles and development in the highly susceptible cultivars, Roma VF, Roforto, Lyallpur selection and PARC-2. late development and low penetration were observed in moderately resistant tomato cultivars PARC. These studies have provided basic information o the infectivity of these pathogenic nematode on their respective set cultivars which could help in further investigation for the development of effective control measures.