Modulation of Plant Growth and Antioxidative Defense System Through Endophyte Bio-Priming in Cotton ( Gossypium Spp.) and Non-Host Crops

Abstract

Seed bio-priming is very promising in improving seed health by mitigating various biotic and abiotic stresses. In this study, the effect of bio-priming with cotton endophytes on seed germination and other growth parameters in host and different non-host crops like wheat, sorghum, cowpea and chick pea was examined. The endophytes were antagonistic against cotton pathogens Corynespora cassiicola and Fusarium solani under in vitro. Among the eight endophytes, CFR-1 and CEL-48 were highly efficient with inhibition of 66.16% and 64.24% respectively against C. cassiicola. Seed bio-priming enhanced seed germination in cotton and non-host crops whereas seed vigor index was highest in bio-primed cotton. Moreover, growth promotion parameters like total soluble protein, total sugar and reducing sugar were also enhanced in host as well as non-host crops upon endophyte bio-priming. Total sugar content ranged from 5.46 to 7.54 mg/g F.W in cotton. Interestingly, the antioxidant potential in all the bio-primed crops were improved with increased catalase and peroxidase activity. Specific activity of catalase ranged from 0.42 to 1.90 µmole/min/mg protein in cotton, while highest activity was reported in CEL-48 primed wheat. The findings of this investigation emphasize seed bio-priming with endophytes for sustainable plant health management.

Keywords: endophytes, Cotton, seed bio-priming, Antioxidants, Total sugar, Catalase