摘要：
[目的]科学评价桉树无性系在不同立地条件下的抗性和适生性,为桉树 "适地适树"种植提供科学依据.[方法]从成活率、树高、胸径、发病率、风害率以及材积等方面,在广东、广西6种不同立地条件下,开展了目前主要推广种植的10个桉树无性系的适生性对比试验.[结果]杂交桉树无性系仍然保持着其适应性强的优良特性,成活率除LH9224为93.7%以外,其余全部在95.0%以上.不同立地条件下各无性系的抗病能力存在较大差异,无性系中以LH9224发病率最高,平均超过6.7%,LH9211没有病株,抗病性最强;立地类型中的黏重土壤发病率最高,平均为3.63%,轻质砂壤土为0.各无性系间的抗风性存在显著差异,在平均风力为9级时,1.5年生幼林的风害率为5%~64%,DH3327和DH3226的抗风性最差,风害率大于60%,LH9211、LH9224和Sh1的抗风性最强,风害率小于10%;6年生成林则以M1和DH2012的风折情况较为严重,遇11级大风时,风折率>12%.各无性系间的速生性也存在极显著差异,8.5年生时年均出材量(MAI)为17.19~38.87 m3·hm-2·a-1,其中以钦廉试验地的DH3213表现最好,U6表现最差, 6种立地条件下6.5年生时,10个桉树无性系的平均MAI为12.24~26.97 m3·hm-2·a-1.[结论]台风频发地区可多种植抗风性强的尾细桉E.urophylla×E.tereticornis系列的LH9224无性系,而在内陆少有风害的地区,DH3213和DH3327是较为理想的种植品系,对于成活率最差和发病率最高的唐家等地区,适宜选择成活率最高的M1和抗病性较好的LH9211,而对于出材率较差的吴川和遂溪等地区,适宜选择速生性最佳的DH3213.%[Objective] To evaluate scientifically the resistance and adaptability of Eucalyptus clones at different stand conditions, and provide a scientific basis for planting proper trees at different areas.[Method]The adaptability of ten eucalyptus clones were compared at six sites in Guangdong and Guangxi Provinces.The survival rates, tree heights, diameters at breast height, incidence of disease, wind damage rates and volumes were studied.[Result]Hybrid Eucalyptus clones kept excellent characteristics of strong adaptability, and the survival rates were above 95% except for LH9224(93.7%).There were large differences in disease resistance among clones at different sites.LH9224 had the highest incidence of disease (averaged over 6.7%), while LH9211 had the highest disease resistance with no diseased plant.The incidence of disease was the highest (3.63%) under heavy clay soil condition, and 0 under light sandy soil condition.There were significant differences in wind resistance among clones.Under the average wind speed of nine grade, the wind damage rates for the 1.5-year-old young forests ranged from 5% to 64%, DH3327 and DH3226 had the poorest wind resistance with above 60% wind damage rates, and LH9211, LH9224 and Sh1 had the highest wind resistance with below 10% wind damage rates.For the 6-year-old forests, M1 and DH2012 had the poorest wind resistance with above 12% windthrow rates under the 11-grade wind.There were highly significant differences in growth speed among clones, and the mean annual increments(MAI)for the 8.5-year-old forests ranged from 17.19 to 38.87 m3·hm-2·a-1.DH3213 at Qinlian had the fastest growth, while U6 at Qinlian had the least growth.The average MAI from six sites ranged from 12.24 to 26.97 m3·hm-2·a-1 for ten Eucalyptus clones.[Conclusion]In typhoon-prone areas, LH9224 clone with strong wind resistance is suggested to be planted, while DH3213 and DH3327 clones are the desired strains for the inland areas with little wind damage.In Tangjia area with the lowest survival rate and the highest incidence of disease, we suggest planting M1 with the highest survival rate and LH9211 with the highest disease resistance, and for Wuchuan and Suixi areas with low volume production, the best choice is DH3213 with the fastest growth rate.
