宁夏杏、李子花期幼果期霜冻指标试验研究

霜冻是制约宁夏经济林果生产的主要农业气象灾害之一，探究不同果树霜冻指标可为果树霜冻预报、监测预警及果树霜冻灾害风险评估和灾害防御提供参考。本研究采用人工霜冻模拟箱模拟霜冻试验，对杏树、李子树开花期及幼果期遭受霜冻的临界温度及持续时间开展研究，结果表明：2个杏品种‘金太阳’和‘李梅杏’花期遭受霜冻的温度指标差异不大，-2℃为轻度受冻，-2~-3℃之间为中度受冻，＜-3℃持续时间大于1 h则为重度受冻。4个李子品种花期‘尤萨’的耐冻性较强，在-3℃下持续4 h仅轻微受冻，其他品种在-3℃下就会严重受冻，‘龙园秋李’的耐冻性最差，-3℃持续1 h受冻率就会达到50%。杏幼果在-2.5℃持续1~2 h为轻度受冻，3~4 h为中度受冻，小于或等于-3℃持续1 h及以上为重度受冻，2个品种差异不大。李子幼果的耐冻性差于杏幼果，‘尤萨’在-1℃持续3~4 h和-2.5℃持续1 h就会轻度受冻，-2℃和-2.5℃时持续时间大于等于2 h或者遇-3℃低温就会重度受冻。‘兰蜜李’-2℃和-2.5℃大于或等于3 h或者温度小于等于-3℃为重度受冻。

Experimental Study on Frost Index of Apricot and Plum in Ningxia Province

Frost is one of the main agricultural meteorological disasters restricting the production of economic fruits. To study the frost index could provide effective reference for frost forecast, monitoring, early-warming, frost risk assessment as well as disaster prevention. The author focused on the critical temperature and time of duration of suffering frost in full blossom and young fruits of apricot and plum by simulated frost experiment using plant growth chamber. The results showed that: there was no significant difference in ‘Jintaiyang’ and ‘Limeixing’ concerning the index of frost, light frost would happen when temperature reached -2℃, and medium frost would happen when temperature reached -2℃--3℃, and when temperature was below -3℃ and lasted for 1 hour，the flower would suffer serious frost. ‘Yousa’ had the strongest cold resistance in 4 plum varieties, for which the light frost would happen when temperature lasted for 4 hours at -3℃, but for the other varieties, serious frost would happen when temperature reached -3℃, and ‘Longyuanqiuli’ had the worst cold resistance, its rate of frost injury would reach 50% when temperature lasted for 1 hour at -3℃. For young fruits of apricot, light frost would happen when temperature lasted for 1-2 hours at -2.5℃, medium frost would happen when temperature lasted for 3-4 hours at -2.5℃ and heavy frost would happen when temperature lasted for more than 1 hour at -3℃ or below, there were no significant differences between the two varieties. The cold resistance of plum was weaker than that of the apricot in young fruits. For ‘young’ fruits of Yousa of plum, light frost would happen when temperature lasted for 3-4 hours at -1℃ or lasted for 1 hour at -2.5℃ and heavy frost would happen when temperature lasted for more than 2 hours at -2℃ or -2.5℃ or temperature below -3℃. For young fruits of ‘Lanmi’ of plum, heavy frost would happen when temperature lasted for more than 3 hours at -2℃ or -2.5℃or temperature below -3℃.