薄壳山核桃17个家系种子性状和子代苗期性状变异及初步选择

Variation and Preliminary Selection of Seed Traits and Seedling Traits in 17 Pedigrees of Carya illinoensis

以17个优树自由授粉家系种子和子代一年生苗为试验材料,分析了种子性状和幼苗生长差异,并进行相关分析和主成分分析,以探讨薄壳山核桃不同家系种子性状、变异规律及与子代苗期生长的关系。结果表明:薄壳山核桃家系间种子性状、幼苗生长存在丰富的变异,种子性状变异系数为1.63%~11.85%,幼苗生长的变异系数为4.91%~17.26%,种壳厚、发芽率、茎干重和叶干重因变异程度高,可作为育种和优良单株选择重要性状指标;百粒重与种长、种宽呈极显著正相关,长/宽与种长呈极显著正相关,与种宽呈负相关但不显著,说明其长/宽主要取决于种长。种子的种宽变化很小,种长变化较大,地径与种长呈显著负相关,说明种子过长对植株增粗生长有阻碍作用;通过主成分综合评价,初步筛选出家系1、8、4、3、7、12号和9号表现较优的子代,为薄壳山核桃优良植株选择提供参考。

Taking the seeds and 1-year seedlings of 17 excellent tree free-pollinated pedigrees as test materials,the seed traits and seedling growth differences were analyzed,and the correlation analysis and principal component analysis were carried out to explore the seed traits and variation rules of different pedigrees of Carya illinoensis and the relationship with the growth of the offspring.The result showed that there were abundant variations in seed traits and seedling growth of Carya illinoensis families,the variation coefficient of seed trait was 1.63%-11.85%,and the variation coefficient of seedling growth was 4.91%-17.26%.The variation degree of seed shell thickness,germination rate,stem dry weight and leaf dry weight was high,which could be used as important traits indicators for breeding and excellent individual plant selection.The hundred-grain weight was significantly positively correlated with the length and width of the seed.The aspect ratio was significantly positively correlated with the species length,while it was not significantly negatively correlated with the species width,which indicating that the aspect ratio depends mainly on the species length.The width variation of the seed was small while the length changed greatly,and the ground diameter was significantly negatively correlated with the seed length,indicating that the excessive length of the seeds hindered the growth of the plants.Through the comprehensive evaluation of principal components,the offspring of the families 1,8,4,3,7,12 and 9 with better performance were preliminarily screened out,providing reference for the selection of fine plants of Carya illinoensis.