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采用田间调查及人工模拟冰冻鉴定的方法，比较测定了4个桂花品种的抗冻性，其抗冻性强弱顺序为金桂（Osmanthusfragransvar．thunbergii）＞银桂（O．fragransvar.latifolius）＞丹桂（O．fragransvar．aurantiacus）＞四季桂（O．fragransvar.semperflorens）。筛选出5株抗冻性最强的单株，它们的致死温度都在－26℃左右。桂花叶片膜脂脂肪酸组成随季节呈周期性变化，随着气温下降亚麻酸（18∶3）含量增加而亚油酸（18∶2）含量降低。不同品种均表现出一致的变化趋势，抗性强的品种这种变化则更为显著。在自然脱锻炼过程中，叶面喷施脱落酸（200ppm）能使亚麻酸含量保持稳定，延缓桂花的脱锻炼。
The frost resistance of four sweet-scented osmanthus cultivars was determined by field investigation and artificial simulation freezing. The order of frost resistance was Osmanthus fragrans var. Thunbergii> O. fargrans var. Latifolius> O.fragransvar.aurantiacus> O.fragransvar.semperflorens. Five strains with the strongest frost resistance were screened, their lethal temperature was about -26 ℃. The fatty acid composition of membrane lipid in sweet-scented osmanthus leaves varied periodically with the seasons, and the content of linoleic acid (18: 2) decreased with the increase of linolenic acid (18: 3) content. Different varieties showed a consistent trend of change, resistant varieties of this change is even more significant. In the natural de-estrus process, foliar application of abscisic acid (200ppm) can make linolenic acid content remained stable, delaying Osmanthus de-exercise.