Department of Plant Pathology, Punjab Agricultural University, Ludhiana-141004
National Symposium on “Plant Pathology in the Changing Global Scenario” held at National Bureau of Plant Genetic Resources, New Delhi on February 27–28, 2009
The total phenols, total flavanols, ortho-hydroxy phenols and chlorophyll content in leaves infected with Alternaria brassicicola in ‘PG-26’ cultivar of cauliflower were estimated after providing protective spray application of seven different potassic and phosphonic resistance inducer salts viz., NH4H2PO4, KH2PO4, K2HPO4, KOH, H3PO3, K2SO4 and salicylic acid (SA), at 0.5, 1.0, 2.0 and 4.0 ml/l. The levels of all the biochemical constituents were higher in the protected cauliflower plants than in unprotected control. Total phenols, total flavanols and total ortho-hydroxy phenols in cauliflower leaves varied significantly with the different salt treatments. Their maximum level was recorded in case of KH2PO4 followed by K2HPO4, KOH, H3PO3, K2SO4, SA and NH4H2PO4. Maximum chlorophyll content (1.28 mg/g) was recorded in case of KH2PO4 that was at a par with 1.15 and 1.07 mg/g in the case of K2HPO4 and H3PO3, respectively. The maximum ratio of chlorophyll ‘a’ and chlorophyll ‘b’ of cauliflower leaves was recorded in the case of K2SO4. These results highlight the importance of potassic and phosphonic salts in determining induction of resistance in cauliflower against Alternaria blight by enhancing the production and accumulation of aforesaid bio-chemicals in cauliflower foliage, which may result in the development of a novel, eco-friendly and long-term strategy for cauliflower protection by activating host defense system.
