We evaluated the effects of Ralstonia solanacearum (Rs) induced biotic stress in three mangroves, viz., Avicennia officinalis, Derris trifoliata and Excoecaria agallocha. These plants were grown in pots as well as hyd...We evaluated the effects of Ralstonia solanacearum (Rs) induced biotic stress in three mangroves, viz., Avicennia officinalis, Derris trifoliata and Excoecaria agallocha. These plants were grown in pots as well as hydroponic systems with sufficient controls, and about 8 × 104 colony forming units of Rs suspension was injected into the healthy test plants (saplings). The plants were subjected to biochemical and isozyme analyses. Upon induction of Rs stress, highly significant (p 0.01) biochemical changes (%) were noticed in respect to controls: carbohydrate content was generally high (24-36) in all plants;hydroponic mangroves showed higher starch content, mangroves under hydroponic system showed increased reducing sugars (29-46), almost all mangroves showed increased protein content;phenolics showed a swing of decrease or increase between plants grown in pot and hydroponic systems;and all plants in general showed higher proline content. Regarding oxidative stress isozymes (OSE) and superoxide dismutase (EC1.15.1.1), mangroves showed 1 or 2 additional isozymes with comparable relative mobility;similarly 1 or 2 additional peroxidase (EC1.11.1.7) isozymes were found in mangroves grown under hydroponic system. Briefly, Rs induced biotic stress did not cause any wilt symptom in all the 3 mangroves tested, but their normal biochemical and OSE patterns, especially of those grown as hydroponics were elicited to significantly higher levels.展开更多
文摘We evaluated the effects of Ralstonia solanacearum (Rs) induced biotic stress in three mangroves, viz., Avicennia officinalis, Derris trifoliata and Excoecaria agallocha. These plants were grown in pots as well as hydroponic systems with sufficient controls, and about 8 × 104 colony forming units of Rs suspension was injected into the healthy test plants (saplings). The plants were subjected to biochemical and isozyme analyses. Upon induction of Rs stress, highly significant (p 0.01) biochemical changes (%) were noticed in respect to controls: carbohydrate content was generally high (24-36) in all plants;hydroponic mangroves showed higher starch content, mangroves under hydroponic system showed increased reducing sugars (29-46), almost all mangroves showed increased protein content;phenolics showed a swing of decrease or increase between plants grown in pot and hydroponic systems;and all plants in general showed higher proline content. Regarding oxidative stress isozymes (OSE) and superoxide dismutase (EC1.15.1.1), mangroves showed 1 or 2 additional isozymes with comparable relative mobility;similarly 1 or 2 additional peroxidase (EC1.11.1.7) isozymes were found in mangroves grown under hydroponic system. Briefly, Rs induced biotic stress did not cause any wilt symptom in all the 3 mangroves tested, but their normal biochemical and OSE patterns, especially of those grown as hydroponics were elicited to significantly higher levels.