Influence of atmospheric gases,particularly ethylene,on somatic embryogenesis of Hevea brasiliensis

The atmosphere of the culture vessel is an important factor for successful somatic embryogenesis in Hevea brasiliensis (Müll. Arg.). Considerable release of carbon dioxide and ethylene occurred during the development of calli. By avoiding the accumulation of gas, unconfined conditions were the most favourable for inducing somatic embryogenesis. Trapping of ethylene was as favourable for calli development and for somatic embryogenesis as unconfined conditions. Inhibition of ethylene synthesis by the adding of aminooxyacetic acid to the medium, also favoured the embryogenic process, and inhibition of ethylene action by the adding of silver nitrate to the medium enhanced significantly embryo production.Abbreviations ACC 1-aminocyclopropane-1-carboxylic acid - AOA amino-oxyacetic acid