5年生马尾松生长性状3地点家系变异及评价

目的 研究3个试验点5年生马尾松生长和抽梢性状的家系遗传变异和遗传稳定性，为马尾松各栽植区选择优良材料提供科学依据。 方法 对2014 年营建于湖北京山、湖南桂阳、广东信宜的5年生马尾松家系区域试验林进行生长及抽梢性状调查，分析各性状遗传变异规律及相关性，在此基础上评价家系的稳定性和速生性。 结果 5年生马尾松生长和抽梢性状在家系间、地点间和家系与地点互作间均存在极显著差异。3个试验点各性状的家系遗传力均大于单株遗传力，胸径、树高、轮盘总数和抽梢性状具有较高的遗传力，家系遗传力为0.72~0.96，单株遗传力为0.45~0.88。性状相关分析表明，速生的家系抽梢次数更多，当年抽梢较长，而第1次抽梢长度较短；采用AMMI模型根据家系树高和胸径的稳定性分析得出：ZP325、ZP386家系的树高稳定性最好，ZJ5153、ZJ39家系的胸径稳定性最好，GD8家系的胸径和树高稳定性均最差。以高出各试验点树高和胸径5.00%，且高于各试验点相应的1代种子园对照为速生性评价标准，在湖北京山、湖南桂阳、广东信宜分别评价出13、4和7个速生家系，其中，GLN2和GD7家系在3个试验点既速生又稳定，可作为3地点速生、稳定型优良家系。 结论 5年生马尾松生长和抽梢性状在家系间存在丰富的遗传变异，生长和抽梢性状受到较强遗传控制；速生家系抽梢次数较多，抽梢长度较长，但固定生长量较短；GLN2和GD7家系为3地点速生、稳定型优良家系。

Family Variation and Evaluation of Growth Traits of 5-Year-old Pinus massoniana in Three Sites

Objective To study the genetic variation and genetic stability of young forest growth traits and shoot growth behavior, and provide a reference for the selection of excellent families of Pinus massoniana. Method Forty three clones of P. massoniana were selected as the test samples, in which 7 clones from Fujian Province, 6 clones from Guangxi Zhuang Autonomous Region, 10 clones from Hu'nan Province, 10 clones from Guangdong Province, and 10 clones from Zhejiang Province. The trial sites locate at Jingshan of Hubei Province, Guiyang of Hu'nan Province and Xinyi of Guangdong Province where test forests were established in 2014. The growth traits and shoot growth behavior of five-year-old P. massoniana family were investigated to analyze the genetic variation rule and correlation. On this basis, the stability and fast-growth traits of these families were evaluated. Result The growth traits and shoot growth behavior of 5-year-old P. massoniana were significantly different among families and locations, and the interaction between families and locations was also extremely significant. The family heritability was greater than the individual heritability at the three test locations. The heritability of DBH, tree height, whorled branches number and shoot growth traits was high. The family heritability was 0.72–0.96, while the individual heritability was 0.45–0.88. Trait correlation analysis showed that the fast-growing family had more frequent shoots, and the length of current shoot was longer, while the length of initial shoot was shorter. AMMI model was used to analyze the stability of family tree height and DBH. It was found that the tree height stability of 2 families from Fujian Province (ZP325 and ZP386) was the best, the stability of DBH of 2 families from Zhejiang Province (ZJ5153 and ZJ39) was the best, and the DBH and tree height stability of a family from Guangdong Province (GD8) were the worst. According to the evaluation criteria (5.00% higher in tree height and DBH than the others at each test location and higher than the corresponding 1st generation seed garden), 13, 4 and 7 elite families were evaluated respectively in Jingshan, Guiyang and Xinyi, among them, one family from Guangxi Zhuang Autonomous Region (GLN2) and one from Guangdong Province (GD7) were identified as the fast-growing and stable families at the three sites. Conclusion The growth traits and shoot growth traits of the 5-year-old P. massoniana are rich in genetic variation among families. The heritability of the growth traits and shoot growth traits are strongly controlled by genetics. The fast-growing family has more frequent shoots and longer shoot lengths, but the fixed growth is shorter. GLN2 and GD7 are identified as the excellent families with fast-growing and stable in each test site.