4种常绿水生鸢尾抗寒性的初步研究

A preliminary study on cold resistance of four Iris hexagonus Hybrid cultivars

为探明常绿水生鸢尾的抗寒性,以其4个品种(‘双色’、‘天景2’、‘白色’和‘天景3’)为试材,观察其越冬适应性并对其低温胁迫条件下叶片的相对电导率(REC)、半致死温度(LT50)、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性、可溶性蛋白(WSP)含量等生理指标进行测定。结果表明:4个品种在浙江地区均可越冬;低温胁迫条件下,4个品种的LT50分别为-10.20、-9.35、-6.47、-2.07℃,其REC均呈上升趋势,MDA含量均先下降后上升,SOD活性和WSP含量均先上升后下降。综合4个品种的形态与生理指标,通过隶属函数分析得出‘双色’的抗寒性最强,‘天景2’次之,可尝试用于北方某些地区的园林应用,‘白色’和‘天景3’的抗寒性较差。

To determine cold resistance of four Iris hexagonus Hybrid cultivars, ＇Shuangse＇, ＇ Tianjing 2＇, ＇Baise＇, and ＇ Tianjing3＇, their overwintering adaptabilities were investigated, and the effects of low temperature stress on the leaf relative electric conductivity （REC）, semilethal temperature （LT50）, malondialdehyde （MDA） content, superoxide dismutase （SOD） activity and soluble protein （WSP） content were studied. Results showed that the four cultivars could live through the winter in Zhejiang province. LT.~o temperature of the four cultivars was -10.20, -9.35, -6.47, and -2.07℃, respectively. As the low temperature stress in- tensified, their REC increased, the MDA content decreased first and then increased, while theSOD and WSP activity, increased first and then decreased. Considering the morphological and physiological indices of the four cultivars, subordinate function analysis demonstrated that ＇ Shuangse＇ was the strongest cold resistance cultivar followed by ＇Tianjing 2＇ among the four, indicating both of them could be recommended in landscaping in northern China. The cold re- sistance of ＇Baise＇ and ＇Tianjing3＇ was found relatively weaker.