三种油茶幼苗对低温胁迫的生理响应及其抗寒性综合评价

以普通油茶Camellia oleifera、高州油茶C. drupifera和红花油茶C. semiserrata 1年生幼苗为试材，通过模拟低温胁迫，分别对其进行6 ℃低温处理，持续0、24、48、72 h以及恢复常温25 ℃后处理24 h，测定各处理幼苗的生理指标，并用主成分分析法综合评价3种油茶幼苗的抗寒性。结果表明，3种油茶的叶绿素含量和相对含水量随胁迫时间的延长而下降，而可溶性蛋白含量则随胁迫时间延长显著上升。在低温处理72 h时，高州油茶的叶绿素含量和可溶性蛋白含量与对照相比差异极显著，分别下降了64.67%和上升了705.67%；而普通油茶叶绿素含量和可溶性蛋白含量与对照相比仅下降34.35 %和上升443.10%，表现出较强的抗寒性。3种油茶抗寒性由强到弱的顺序为普通油茶＞红花油茶＞高州油茶。

Comprehensive Evaluation of Physiological Responses to Low Temperature Stress and Cold Resistance of Three Species ofCamelliaSeedlings

One-year-old seedlings ofCamellia oleifera,C. drupifera andC. semiserrata were used as experimental materials, and their physiological characteristics were investigated. The results showed that cholrophyll content and relative water content decreased, but the soluble protein content increased over time in threeCamellia species. After treatment for 72 h, the chlorophyll content and soluble protein were extremely significant difference compared to control inC. drupifera, and decreased by 64.67% and increased of 705.67%, respectively. While the chlorophyll content and soluble protein content inC. oleifera compared with the control only decreased of 34.35% and increased of 443.10%, showing stronger cold resistance. According to principal components analysis (PCA), It was described thatC. oleifera had the strongest resistance for cold stress, followed byC. semiserrataand C. drupifera.