Comparative study on the effects of various plant growth regulators on growth, quality and physiology of Capsicum annuum L.

Abstract

Pre- and post-harvest physiology and quality responses of green pepper (Capsicum annuum L. cv ‘Standar p.13/0211003-01-Agris’) on exogenous Gibberellic acid-GA3 (100 μM), ProhexadioneCalcium (100 mg l -1 ), Cycocel (100 mg l -1 ) and Ethephon (100 mg l -1 ) applied as foliar sprays, were investigated. Among PGRs, GA3 @ 100μM was effective in promoting flowering and better for vegetative characteristics. Chlorophyll a+b concentration of leaves was markedly inhibited by GA3, Prohexadione-Calcium, Cycocel and Ethephon application while, the maximum quantum yield of primary photochemistry (Fv/Fm) and the ratio Fv/Fo was slightly increased under GA3. The above indices were significantly depressed under Cycocel, Ethephon and Prohexadione-Calcium. CO2 production pattern was negatively related with chlorophyll fluorescence (Fv/Fo) yield and ascorbic acid content. The Brix content and the “maturity index” were depressed after ProhexadioneCalcium, Cycocel and Ethephon application. In general, the best green pepper appearance was found under control and GA3 whereas, pre- and post-harvest physiology and quality characteristics dropped sharply and green peppers were not marketable under the three growth retardants.