19种园林绿化树木1年生播种苗越冬研究

为了检测山西中部园林绿化树种播种苗的越冬特性，进而为苗木培育提供实用参考依据，对19种山西中部地区常见的园林绿化树种的1年生播种苗进行了越冬受冻害比较研究。结果表明：（1）五角枫、侧柏、洋白蜡、丝棉木、栾树、山皂荚、暴马丁香和水蜡的1年生播种苗可以在该地区安全越冬，不受冻害影响或受冻害影响很小，适于在该地播种育苗。（2）青桐和木槿的播种苗受冻害影响最重，即使在保护条件下，越冬后苗木保存率仍然很低，不适于在该地区播种育苗。（3）红瑞木、合欢、枫杨、复叶槭、悬铃木、紫荆、香椿、紫薇和梓树苗木越冬时，受不同程度冻害影响，需要继续进行第2~3年的越冬观察。（4）在运用冻害指数时，适当加权第4级冻害可以更客观地反映和比较不同树种苗木的受冻害状况。此研究结果可为这些树种的播种苗培育提供实用参考依据。

Study on Winter Survival of the 1-Year-Old Seedlings of 19 Landscaping Tree Species

In this experiment, freezing injuries in winter for the 1-year-old seedlings of 19 landscaping tree species common in the central Shanxi were compared to examine the winter survival ability of landscaping tree seedlings and to provide a practical reference guide for seedling propagation in the area. The results indicated: (1) the 1-year-old seedlings of Acer mono, Platycladus orientalis, Fraxinus pennsylvanica, Euonymus bungeanus, Koelreuteria paniculata, Gleditsia japonica, Syringa reticulata and Ligustrum obtusifolum could safely survive winter in the area, without or with little freezing injuries. Seedling propagation is appropriate for these species in the area. (2) The seedlings of Firmiana simplex and Hibiscus syriacus suffered most serious freezing injuries, resulting in very low survival rates despite under protection in the winter. Seedling propagation is not appropriate for the two species in the area. (3) The seedlings of Cornus alba, Albizia julibrissin, Pterocarya stenoptera, Acer negundo, Platanus acerifolia, Cercis chinensis, Toona sinensis, Lagerstroemia indica and Catalpa bungei suffered varying degrees of freezing injuries and needed to be observed in the second even third winters to decide if seedling propagation is appropriate for these species in this area. (4) The freezing injury index with properly weighted class 4 could more objectively reflect and compare freezing injuries of the different tree seedlings. The results from this study could provide a practical reference guide for seedling propagation of the 19 species in the area.