关键词: 低温, 倒春寒, 抗冻性, 可溶性糖, 游离氨基酸

Abstract: In order to evaluate the substantial basis of tea plant resisting frost as well as the difference in frost resistance of different cultivars, the tea plantation growing with cultivar Wuniuzao and another plantation growing with Maolü were selected, in which the temperatute was recorded day by day. At the fifth, the fifteenth and the twenty fifth of each month during the experimental duration, the fresh tea leaves were plucked, in which the soluble sugar content was detected by colourimetry, and the proline content and seventeen free amino acid contents were determined by HPLC. The results showed that: ① Within the three durations the temperature dropped continually (from October 20 to December 27 in 2013), the low temperature lasted (from December 28 to February 20), and the temperature rose gradually, accordingly, the soluble sugar content continually raised, and keeped on increasing, then reduced insignificantly, furthermore, the soluble sugar content negatively correlated with temperature in the whole experimental stage. ② Accordingly, the proline content and the seventeen free amino acid content slowly raised, and obviously increased, then markedly promoted. It was considered that: ① The three types of substances were all related to the resisitance on cold injury, and the correlation of the soluble sugar content with low temperature was larger than those of other two types of substances with the temperature. ② The content of these three types of cold-resisting

Key words: substances in cultivar Wuniuzao was more than those in Maolü, at the same time, the frezzing injury index of Wuniuzao was less than that of Maolü, therefore, the Wuniuzao possessed even strong resistance against freezing.