许多资料表明:幼年种子园结实不多,而且不正常。因此,提高种子园产量措施的研究,是目前林木良种繁育的重要任务之一。乔木树种的结实,是由内外特性的许多因素决定的,其中最重要的因素是:年令、树木的基因型和周围环境条件(光、热水份、土壤和病虫害)。中部黑土地带松树种子园的研究表 Numerous sources indicate that young seed orchards are small and irregular. Therefore, the study of measures to improve the yield of seed orchard is one of the important tasks of seed breeding. The robustness of tree species is determined by a number of factors, both internal and external, the most important of which are: year, tree genotypes and surrounding conditions (light, hot water, soil and pests). Study on the Pine Seed Garden in the Black Soil Zone of Central China