国外松种间杂交育种及其F1 代早期生长评价

采用人工控制授粉的方式,开展了湿地松×洪都拉斯加勒比松(湿加松)、火炬松×洪都拉斯加勒比松(火加松)的种间杂交育种工作.杂交种育苗和子代测定均采取随机区组设计,并追踪调查了苗高和定植后的树高.结果显示:苗期湿加松和火加松各个组合间的树高差异显著,而定植前2 a由于处于生长初期,部分生长较快的幼树遭受冻害,各组合间树高差异没有达到显著水平;定植第3、4年火加松各组合间高生长差异极显著,而湿加松各组合问的差异也相对加大,但是没有达到差异显著水平.这表明杂种子代生长评价测定至少应该在定植4～5 a之后,其中湿加松的子代测定评价时间应该比火加松的评价时间更晚.一大批表现较优的火加松组合5年生(包括1 a苗期)平均高度达4.0 m以上,该平均值超过国家速生丰产林林业部标准(H=4.0 m),国外松杂交育种能够高效选择出优良的松树品种.

Study on Hybr idiza tion among Exotic Pines and The ir Early GrowthAssessmen t of F1 Genera tion

The breeding and hybridization among exotic p ines were studied in this paper. 8 F1-hybrids of Pinuselliottii var. elliottii ( PEE) ×Pinus caribaea var. hondurensis ( PCH) and 47 F1-hybrids of Pinus taeda ( PT) ×Pinus caribaea var. hondurensis ( PCH) , which were selected from 17 crosses of PEE ×PCH and 75 crosses of PT ×PCH according to the height order of seedling, were growed for filial generation test with a randomly block design.All trees in the test were measured for height at the age of 3 and 5. The results of variance analysis (ANOVA)revealed that no differences existed among the hybrids on the average height at the age of 3 because of the lowercold2endurance of some young trees, but significant differences appeared at the age of 5 among the crosses,especially the growth differences of PT ×PCH crosseswere extremely significant. Thus the assessment of F1 hybridswould begin 4 years after p lanted in fields. The height of better F1 families of PT ×PCH were higher than 4. 0meters, which exceeds the national standard of good conifer trees. In conclusion, better p ine varieties can beselected effectively through hybridization in exotic p ines.