The influence of exogenous application of kinetin and diaminopurine on the penetration and subsequent development of the root-knot nematode, Meloidogyne incognita were studied in susceptible (Pusa Ruby) and resistant reacting (SL-120) cultivars of tomatoes. Alterations in the level of kinetin, through foliar application, induced susceptible reaction in resistant reacting variety, as judged on the basis of development of egg laying females, fecundity and number of root galls. Furthermore, exogenous application of kinetin resulted in the establishment of feeding sites required for the development of the females. Exogenous application of diaminopurine, known inhibitor of kinetin, led to the resistant responses to M. incognita in a susceptible tomato cultivar. Interference in the utilization of kinetin affected the development of the nematode. Apparently, kinetin had profound influence of the successful development of feeding sites required for the further development of infective larvae into gravid females. Bioassay studies for estimation of cytokinin indicate that the level of endogenous cytokinin is more in Pus a Ruby than SL-120 and resistant as well as susceptible varieties show higher level of cytokinin during post-infection period.
Kinetin, Meloidogyne incognita, biology, diamillopurille
