杉木种子园种子生物学特性的地区及年度变异

本研究目的在于揭示杉木种子园种子品质的变异模式。在1981—1983和1986年,对分布区内不同地区的70个种子园的种子取了样,并进行三个特性即发芽率、涩粒率和千粒重的测定。结果表明,经研究的种子特性在不同年份间和种子园间均存在变异:千粒重随种子园的地理经度降低而变轻;其它两个性状表现出非渐变的生态型(地域性)变异模式。发芽率的变异模式与涩粒率的模式相并行,但二者之间为负相关。这些发现为育种工作者确定建立最适宜的杉木种子园地区,提供了科学依据。

REGIONAL AND TEMPORAL VARIATION OF SEED PROPERTIES OF CHINESE FIR SEED ORCHARDS

The aim of the study was to investigate the variation pattern in seed properties of seed orchards of Chinese fir. Seed samples were taken from 70 seed orchards established at different locations throughout its natural range. The three properties, namely germination rate, percentage of death seed and absolute seed weight, were assessed during 1981-1983, and 1986. The results showed that referring to properties studied, year-to-year and orchard-to-orchard variations were exhibited. The seed weight often decreases with the decrease of longitude, where the seedlots came from. The variation of the other two properties showed the ecotypical (or regional) patterns, no clinal ones. The variation pattern of germination rate closely paralleled the pattern of death seed, bul there was negative relation between these two variables. This finding has been made to help the tree breeders know where the optimum regions are to establish seed orchard of Chinese fir.