24-EPIBRASSINOLIDE REGULATED PHYSIOLOGICAL AND BIOCHEMICAL ALTERATIONS IN NEMATODE INFECTED TOMATO CULTIVAR

Abstract

24-Epibrassinolide (EBL) regulated physiological (percentage germination, plant height, plant biomass and number of galls) and biochemical alterations (antioxidative enzymes and antioxidants) were assessed in nematode infected tomato cv .Pusa Ruby. Contents of some important pigments (Chlorophyll A, B, Total Chlorophyll and Carotenoid content) and few elements (N, C, H) were also analyzed. Tomato seeds were treated with different concentrations of EBL (10-11M, 10-9M & 10-7M) and then allowed to germinate in controlled conditions. After germination, seedlings were inoculated with infective second stage juveniles (J2s) of Meloidogyne incognita and estimations were done 5 days after inoculation (DAI). Two controls i.e. CI and CII were also set. Physiological parameters showed reduced plant growth after nematode infection which was found enhanced after EBL treatment whereas, nematode penetration was restricted in EBL treated seedlings. Pigment analysis showed a decrease in total chlorophyll content in CII seedlings which increased in EBL treated seedlings, whereas carotenoid content showed reverse trend. Similarly, carbon and hydrogen contents found lower in CII, increased in treated seedlings. Regarding biochemical alterations, overall specific activities of all the enzymes and antioxidants were found suppressed after nematode inoculation which increased after EBL treatment.