Seed Priming Through Fungicides, Biocontrol Agents and Botanicals as Effective Method for Controlling Spot Blotch Pathogen, Bipolaris sorokiniana in Barley

This study was carried out to investigate the efficacy of fungicides (mancozeb/carbendazim), biocontrol agents (Trichoderma viride/Trichoderma harzianum) and botanicals (Eucalyptus globulus/Calotropis procera) as seed priming against barley spot-blotch pathogen, Bipolaris sorokiniana (Sacc.) Shoemaker under greenhouse conditions. Experimental results showed that B. sorokiniana inoculation caused significant reduction in growth, yield attributes and chlorophyll content over un-inoculated control. Disease related parameters which include the disease severity, lesion size and number of lesions were developed in pathogen inoculated plants. However, seed priming with fungicides, biocontrol agents, and botanical extracts, both in the presence or absence of pathogen, resulted in a substantial improvement in growth, yield attributes and chlorophyll content of barley plants over their respective control. Among treatments, seed priming with mancozeb at 300 mg/L had greater growth, yield attributes and chlorophyll content followed by other treatments in both inoculated and un-inoculated plants. Similarly, lowest growth, yield attributes and chlorophyll content were observed in pathogen inoculated plants primed with 20% C. procera leaf extracts. Seed priming followed by pathogen inoculation also reduced disease parameters significantly (p ≥ 0.05) over inoculated control. The principal component analysis (PCA) exhibited significant correlations between various studied attributes with 98.34% overall data variability.