印楝种源间抗寒能力比较研究

Cold Resistance Analysis of Neem Provenances

通过组织褐变法、膜脂脂肪酸含量分析和电导法配合Logistic方程求拐点温度的方法,对引种的4个种源抗寒力进行研究评价。结果表明:(1)印楝是一种不耐寒的植物,0℃以下的短暂低温可对其嫩叶造成伤害,低于-1℃保持1h即可造成部分幼苗死亡;(2)印楝种源间抗寒能力差异不显著;(3)叶膜脂脂肪酸组成含量与抗寒力大小无明显相关关系;(4)印楝4种源半致死温度分别为-1 651、-1 675、-1 750、-1 682℃。根据上述试验研究和冷冻处理实验结果,4个印楝种源抗寒力大小排序为IND95003>IND95004>IND95001>IND95002,在我国有低温寒害的地区引种印楝应该慎重,在轻霜地区可选择抗寒力稍强的IND95003种源先行试验性引种。

Neem grows well in the hot-dry valley in China, but it is easy to be harmed by cold.The cold resistance of 4 provenances was valued through tissue browning method, membrane fatty acid analysis and the electric conductivity method which Logistic equation was used to determine the inflexion temperature.The results showed that:(1)neem is a plant which has low cold resistance,short cold temperature below 0 ℃ can damage its tender leaves, and 1h temperature below -1 ℃ will lead part of infant seedlings to death; (2) the cold resistant capability has no distinct difference among neem provenances; (3) membrane fatty acid content of leaves has no correlative relation with cold resistance; (4)the medium lethal temperatures of 4 neem provenances are -1.651,-1.675,-1.75,-1.682 ℃.According to the results above-mentioned and the results of freezing experiment, the cold resistance sequence of neem provenances is IND95003>IND95004>IND95001>IND95002.The results showed that it should be careful to import neem to cold zones in China, and IND95003 can be used in the zones with light frost.