杉木种子园无性系结实稳定性的遗传变异

在安徽西田林场杉木种子园对从福建洋口林场引进的25个无性系,每系固定6株样株,分系分株连续进行6a的结实量观测与分析。结果表明,杉木无性系结实相对产量在年度、重复间稳定性较强,但结实量的年度方差分量较大,占总方差的36．72％,而无性系仅占10．12％,表明种子产量稳定性受气候、生物、环境、人为措施及无性系基因型等多种因素综合影响。同年度中,影响产量的主要因素则是无性系的基因型。以结实量的变异系数(cv)或生态价系数两种方法评价无性系结实稳定性的结果基本一致,但应以多年的结实量与cv或生态价系数综合判断,对无性系再选择均有较高的可靠性和实用性。按该法可把25个杉木无性系划分为高产稳定、中产稳定、低产稳定等9种结实类型。

A Study on the Heredity and Variation of Seed Yielding Stability

The seed yielding stability(SYS) is one of the most important factors affecting seed production in high-generation seed orchard of Chinese fir. Lots of the researches on crop variety stability have been done while only few of seed yielding stability in forest was reported.Exploring the seed yielding stability of Chinese fir seed orchard provides the important basis for re-selecting clones in high-generation seed orchard.There are 25 clones,introduced from Yangkou Tree Farm,Fujian Province,in seed orchard of Chinese fir in Xitian Tree Farm,Anhui Province,which 6 trees were regarded as sample ones in every clone,and seed yielding quantity of these trees was inspected during the 6 years continually.Based on the investigated data,the heredity and variation of seed yielding stability in Chinese fir were discussed in this paper.The results showed that the environmental factors were the key elements to affect seed yielding stability of Chinese fir orchard in the different years,which make up 36.72% of the total variance while Chinese fir clones only account for 10.12% of the total variance.However,the key factor affecting seed yield in Chinese fir orchard was clone genotype in the same year.By means of the variation coefficient of seed yield(cv)or ecovalence coefficient of seed yielding stability,the 25 clones of Chinese fir could be divided into three groups,eg.High-stable,mid-stable and low-stable and nine seed bearing types.The results in the paper would provide an important basis for re-selecting clones in the next generation seed orchards.