钩锥种子及其苗木性状的遗传变异研究

Study on Variation in Traits of Seed and Seedling and Their Inheritance in Castanopsis tibetana

2013年10月在浙江省龙泉市、安徽省休宁县的16颗钩锥Castanopsis tibetana母树采集种子,2014年2-3月在浙江省淳安县播种,4月上杯。2015年1月和2016年1月测定相关数据。结果表明,种子纵径9.66~25.19 mm,横径8.05~19.89 mm,种形指数0.79~1.79;发芽率6.67%~87%,生活力10.00%~93.33%,单粒种子重0.93~2.54g;1年生苗高3.00~40.00 cm,1年生地径0.66~7.13 mm,2年生苗高9.00~124.8 cm,2年生地径1.62~12.07 mm;变异系数最大的是发芽率,达61.31%,最小的为种形指数(11.67%)。钩锥地理种源及母树间种子表型、萌发性状及幼苗生长性状变异丰富,差异均达到极显著水平。种子质量对苗木的生长有一定的影响。龙泉种源种子及幼苗性状变异幅度小于休宁,但表现优于休宁种源;种源水平上种子质量相关参数发芽率、生活力、单粒种子重的遗传力相对较高,分别为0.50,0.83,0.90;从采种母树的遗传力来看,最大的为种形指数,达0.80,其次为发芽率(0.73),而种子大小及苗木生长性状的遗传力则较低。

Seed collections were carried out from 16 mother Castanopsis tibetana trees in Longquan of Zhejiang and Xiuning of Anhui province on October of 2013. On February and March, sowing was made in Chun＇an, Zhejaing province, and seedlings were transplanted on April. Determinations were conducted on January of 2015 and 2016. Results demonstrated that the seed vertical diameter ranged from 9.66 to 25.19 mm, seed transverse diameter from 8.05 to 19.89 mm, seed shape index from 0.79 to 1.79, germination rate from 6.67% to 87%, seed viability from 10.00% to 93.33%, single seed weight from 0.93 to 2.54 g, height of 1-year seedling from 3.00 to 40.00 cm, ground diameter from 0.66 to 7.13 mm of 1-year seedling, height of 2-year seedling from 9.00 to 124.8 cm, and from 1.62 to 12.07 mm in ground diameter of 2-year seedling. Germination rate had the highest variable coefficient, about 61.31%, and the lowest was seed shape index（11.67%）. There were significant difference of seed phenotype, germination trait and seedling growth among different provenances and mother trees. Seed quality had effect on seedling growth. The experiments showed that seeds from Longquan and their seedlings had lower variance but better performance than that from from Xiuning. Germination rate, seed viability and single seed weight of the same provenance had a relatively high heritability（0.50, 0.83 and 0.90）, but in terms of mother trees, the maximum heritability was found in seed shape index（0.80）, followed by germination rate（0.70）. The heritability of seed size and seedling growth traits was low.