Effect of salicylic acid and calcium chloride in induction of resistance against spot blotch of barley

Barley (Hordeum vulgare L.) is an important crop belonging to gramineae family and has been serving as the major portion of diet of humans and feed for animals.Among fungal diseases of barley, Bipolaris sorokiniana(Sacc.) Shoemaker (syn. Helminthosporium sativum, teleomorph: Cochliobolus sativus) is an economically very important fungal pathogen causing spot blotch disease. The fungus causes germination failure, seed mortality and spot blotch development in both wheat and barley. In the present study, field trials using barley cultivars PL426 and DWRUB52 were conducted to study the effect of chemical compounds i.e. salicylic acid (0.01, 0.02 & 0.03%) and calcium chloride (0.1, 0.2 & 0.3%) in induction of resistance against foliar blight of barley. The results revealed that in cultivar PL 426, maximum disease control (45.24%), maximum per cent increase in yield (60.00%)and protein content (15.00%) were recorded when the plants were sprayed with salicylic acid @ 0.03% followed by calcium chloride @ 0.3%. Similarly, in cultivar DWRUB 52, maximum disease control (48.29%), maximum increase in yield (15.60 q/ac) were recorded when the plants were sprayed with salicylic acid @ 0.03% followed by calcium chloride @ 0.3% while the per cent increase in protein content was observed to be similar in both these treatments in cultivar DWRUB 52. In present investigations, the chemical compounds (salicylic acid and calcium chloride) could induce resistance against spot blotch as reflected by disease control, increase in yield, increase in protein content and increase in phenolic content. Salicylic acid @ 0.03% was most effective in inducing resistance. However, calcium chloride proved more effective in increasing phenolic content in both the cultivars.