三角梅在咸宁市不同环境条件下越冬的抗寒表现

Cold Response of Overwintering Bougainvillea glabra under Different Environments in Xianning City

三角梅(Bougainvillea glabra Choisy)在咸宁市因冬季低温进入被迫休眠,同品种同类型的三角梅在不同环境所致的不同开花状态下进入休眠的早晚不同,开花状态的三角梅进入休眠相对较晚。三角梅在越冬期蒸腾强度呈现逐渐减弱的趋势,越冬期因叶片蒸腾和土面水分蒸发使盆土相对含水量日下降0.5%左右。当气温低于-4℃时三角梅受冻;如果没有叶片的防冻保护,三角梅在-2℃就受到低温和寒风的危害,受害程度与风力的大小有关。

Bougainvilleas（Bougainvillea glabra Choisy） in Xianning city were forced to be dormant because of low temperature in winter. Bougainvilleas of the same cuhivar or the same type under different flowering status caused by different environ- ments became dormancy at different time. The flowering bougainvilleas became dormancy later. Transpiration rate of overwin- tering bougainvilleas showed a declining trend. Water content in bougainvillea pots soil decreased by about 0.5% per day due to leaf transpiration and water evaporation. The bougainvilleas would suffer freeze injury when temperature was under -4 ℃; and would be damaged by low temperature and cold wind at -2 ℃ if without frost protection of leaves. The damage extent was correlated with the speed of wind.