Abstract: Intact etiolated seedlings of pea (Pisum sativum L. cv. guangzhou honqhua) were used to investigate the changes in the physiological activities by the treatment with fusicoccin (FC), ethylene, and FC + ethylene respectively with the aim of understanding the fusicoccin-ethylene interaction. After the combined application of FC and ethylene, FC may partly removes the inhibition of elongation and fresh weight caused by ethylene. However, that the reduction of DNA synthesis and cell division resulted from ethylene can not eliminated by FC. Ethylene induces the microfibril of cell wall to orientate longitudinally while FC alters microfibrillar orientation by random deposition. FC is also capable of decreasing the inhibition of K+ uptake, H+ secretion and respiratory rate caused by ethylene. The authors consider that the cause of FC partly antagonize ethylene on reversing ethylene-inhibited growth appears not to be reduced the content of endogenous ethylene, but may be caused by raising the respiratory rate, stimulating the H+ secretion and K+ uptake. Eventually, cells uptake much water and result in increase of their elongation and swelling.

Key words: Fusicoccin, ethylene, pea, cell wall microfibril, H+ secretion, K+ uptake, respiratory rate