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银杏的经济价值很高,但生长较慢,结种较晚,特别初种期产量低.为了促进银杏速生和早实丰产,山东省郯城县科委、林业局,从1978～1983年进行了银杏矮化、密植、早期丰产的试验研究,取得了嫁接后3年结种、5年亩产白果194公斤的成果,比稀植同龄银杏亩产提高6倍,结种树龄也由过去的20多年提前了10多年,达到了国内先进水平.1 银杏早实丰产的基础银杏为裸子植物,雌花即大孢子叶球发生于叶原基,构造简单,不如苹果、梨、桃等被子植物的花器复杂而完善.由于叶原基比芽原基形成花芽营养要求低,故成花容
The economic value of Ginkgo biloba is very high, but it grows slowly, the seed production is late, and the yield is low especially in the early seed stage. In order to promote fast growing and early yielding of ginkgo, Shandong Science and Technology Commission and Forestry Bureau of Tancheng County conducted from 1978 to 1983 Ginkgo dwarf, dense planting, early high yield experimental study, obtained grafting 3 years after grafting, 5 years yield of 194 kg of ginkgo fruit per plant, compared with the same planting ginkgo seedlings increased 6-fold, the tree age from the previous 20 Many years ahead of more than 10 years, reaching the domestic advanced level.1 Ginkgo biloba early fruiting and yielding is a gymnosperms, the female flower megasporophyll occurs in leaf primordia, simple structure, as apples, pears, peaches and other angiosperm flower complex and Perfect.Because leaf primordia than bud primordia to form a flower bud nutrition requirements are low, so into flowers