Variability in Production of Extracellular Hydrolytic Enzymes by Trichoderma spp. and Induction of Resistance in Gram (cicer arietinum)

Abstract

Ten isolates of Trichoderma spp. isolated from rhizosphere region Of different crops were evaluated for their ability to produce extracellular hydrolytic enzymes, viz., β-1, 3 glucanase, chitinase and cellulase enzymes with different concentrations ef carbon sources, pM, and temperature levels and the induction of systemic resistance in gram seedlings. Highest chitinase and β-1, 3 glucanase activity were observed in TR₂ isolate whereas TH₂ isolate exhibited highest activity of cellulase. TH₁ and TH₅ were the next best isolates in their chtinase enzyme activity. Similarly, TR₁ and TH₁ isolates followed the TR₂ for β-1, 3-glucanase activity. The activity of cellulase was highest in TH₂ isolate followed by TH₅ and TR₂, which were statistically significant. The enzyme β-1,3 glucanase was produce in media with pH 4.0 to 8.0 with an optimum pH5.5. The optimum pH for chitinase and cellulase enzyme activity was recorded at 5.0. With the variable temperatures, i.e., 20, 25, 30, 35 and 40°C, the enzyme activities of all three enzymes showed highest at 30°C. The activities of enzymes β-1,3 glucanase and chitinase was recorded highest at 3.0 and 4.0% concentrations of glucan and chitin, respectively whereat 0.75% concentration of cellulose showed highest cellulase activity. The highest induced resistance by Trichoderma isolates in gram seedlings, was recorded by TR₁, through the increase activity of PAL and β-1,3 glucanase and TH₁ by enhance activity of peroxidase enzyme.