Induction of systemic acquired resistance in susceptible and resistant cultivars of chickpea (Cicer arietinum L) genotypes: A comparative study in response to salicylic acid and spermine

Abstract

The induction of systemic acquired resistance (SAR) by salicylic acid (SA), spermine (Spm) and SA+Spm was investigated in two different genotypes of chickpea cv L550 and ICCV10 which were susceptible and resistant to wilt disease caused by Fusarium oxysporum f sp ciceri, respectively. The levels of H 2O2 were higher in roots and shoots of susceptible cultivar L-550 than that of the resistant cultivar (ICCV-10). The activities of catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX) and super oxide dismutase (SOD) were enhanced significantly after treatment with SA, Spm and SA+Spm in both the cultivars. The inductions of multiple isoforms of catalase were observed in roots and shoots of susceptible cultivar and they were insensitive to SA treatment. However, no induction of catalases was observed in either roots or shoots of resistant cultivar, and the native CAT-2 was inhibited. Instead, induction of POD isoforms, chitinase (PR-3) and ?-1,3-glucanase (PR-2) were observed in the resistant cultivar. Considerably higher intrinsic levels and increased activities of antioxidant enzymes in susceptible cultivar and decreased levels in resistant cultivar under the influence of SA, Spm and SA+Spm induced stress, support the possible role of these enzymes in the systemic acquired resistance.