华北落叶松扦插生根能力的遗传变异及选择

Individual and family variations in rooting ability of Larix principis rupprechtii Mayr.

为揭示华北落叶松扦插生根能力的遗传变异规律和提高选择利用效率 ,对 4～ 8龄全同胞优良单株、全同胞家系、半同胞优良单株和半同胞家系幼树的嫩枝插条 ,采用自控喷雾进行了扦插试验 .生根率、根重量、根条数和根长度间呈高度遗传相关 ,生根率是反映生根能力高低的主要指标 .生根能力的差异主要受基因加性效应控制 ,对生根能力选择利用效果明显 ,单株选择较家系选择效果好 ,其中以全同胞单株选择利用潜力最大 .采穗母树的生长与生根不相关 ,速生单株的生根能力与家系生根能力也不相关 .在速生全同胞家系中选择生长快、生根能力强的单株 ,进行控制授粉 ,按生根和生长性状进行轮回选择 。

This study is to investigate the genetic variation pattern and selection potential on cutting rooting ability of Larix principis rupprechtii Mayr. Using automatic mist system, the cutting experiments were carried out with different materials from individuals and families of full sib and half sib, as well as grafted trees at ages of 4 to 8. High correlations were detected among the rooted rate ( main index ), weight, amount and length of roots. Variation in rooting ability is mainly affected by gene additive effect. Selection for rooting capacity and its utilization is effective and individual selection is more effective than family one. However, the greatest selection potential was noticed in full sib individuals. No correlation was found between the rooting character and growth trait. The greater genetic improvement in rooting capacity will be realized, if recurrent selection is carried out with full sib originated from high rooting ability and fast growing parents.