不同种源高山栲种子性状特征及其变异

Characteristic and variation in seed traits of Castanopsis delavayi from various provenances

【目的】研究不同地理种源间高山栲种子性状特征及其与地理、气候因素间的变化规律,探究高山栲种群的生态地理分布规律,为高山栲优良种源的早期选择提供科学依据。【方法】以高山栲主要自然分布区域内9个地理种源的高山栲种子为研究对象,在每个地理种源内选取15棵健康的母株,去除壳斗后每株选取10粒正常、饱满的种子,测定种子的种高、种宽、种形指数、单粒鲜质量、单粒干质量和千粒质量等指标,并进行方差分析、回归分析和聚类分析。【结果】在9个高山栲地理分布区域内,种子质量性状的稳定性显著低于种子形状指标(P<0.001)。高山栲平均种高为11.24 mm,平均种宽为10.45 mm,平均种形指数为1.08,平均单粒鲜质量为0.97 g,平均单粒干质量为0.61 g,平均千粒质量为974.34 g。种子性状在不同种源间均存在极显著差异(P<0.001),其中以剑川种源的种子形状与质量指标最高,剑川种源的平均种高为13.66 mm,平均种宽为12.52 mm,平均单粒鲜质量为1.55 g,平均单粒干质量为0.97 g,平均千粒质量为1551.65 g。各种源高山栲种子性状均随着经度的减小和海拔的增加呈现不断增大的趋势,且与年均温度(MAT)和年均降水量(MAP)间存在极显著负相关关系。【结论】受地理和气候因素的影响,不同种源间高山栲种子性状存在显著差异,该研究对于开展高山栲优良种质资源的筛选工作及理解高山栲的地理分布格局具有重要意义。

【Objective】The characteristics of seed traits of Castanopsis delavayi from different geographical provenances and their changes with geographical and climatic factors were studied to explore the ecological and geographical distribution of Castanopsis delavayi population and provide scientific basis for the early selection of excellent provenances of Castanopsis delavayi.【Method】The seeds of Castanopsis delavayi from nine geographical provenances in the main natural distribution areas of Castanopsis delavayi were taken as the research objects.Fifteen healthy parent plants were selected from each geographical provenance,and 10 normal and full seeds were selected from each plant after removing the bucket.The seed height,seed width,seed shape index,single-seed fresh weight,single-seed dry weight and thousand-seed weight of the seeds were measured,and variance analysis,regression analysis and cluster analysis were performed.【Result】In the nine geographical distribution areas of Castanopsis delavayi,the stability of seed weight traits was significantly lower than that of seed shape index(P<0.001).The average seed height was 11.24 mm,the average seed width was 10.45 mm,the average seed shape index was 1.08,the average single seed fresh weight was 0.97 g,the average single seed dry weight was 0.61 g,and the average thousand seed weight was 974.34 g.There were significant differences in seed traits among different provenances(P<0.001).The seed shape and weight of Jianchuan provenance were the highest.The average seed height of Jianchuan provenance was 13.66 mm,the average seed width was 12.52 mm,the average single seed fresh weight was 1.55 g,the average single seed dry weight was 0.97 g,and the average thousand seed weight was 1551.65 g.The seed traits of Castanopsis delavayi from different provenances showed an increasing trend with the decrease of longitude and the increase of altitude,and there was a significant negative correlation between MAT and MAP.【Conclusion】Affected by geographical and climatic factors,there were significant differences in seed traits among different provenances of Castanopsis delavayi.This study plays an important role in screening excellent germplasm resources and understanding the geographical distribution pattern of Castanopsis delavayi.