引种D01杨树的生长规律研究

D01杨树从美国的阿肯色州引种到长江中游洞庭湖流域的低山、湖滨地段以及长江南面的红壤丘陵地带。对D01杨树的引种调查研究表明：D01杨树繁殖容易、萌芽力强、生长周期短;无性扦插木的年生长量变化呈＂M＂形;D01杨树在初夏生长迅速,秋季中期后落叶并进入休眠期,次年三月再次萌芽,其年生长周期为6个月;昼夜温差、年平均气温和日照时间是影响D01杨树生长的主要气象因子。

The growing regularity of introduced DO1 Poplar

D01 Poplar were introduced to the lower hills or branches of the Dongting Lake System in the middle reaches of the Changjiang River and the red soil hills on the south of the river from Arkansas of the United States. The results of introducing investiga- tions showed that D01 Poplar trees reproduced easily and sprouted vigorously and their annual growing period was short and could be out annually. The annual growing amount of its asexual eutting wood assumed a ＂M＂ form. The trees grew rapidly in the early summer. Their leaves fell after the middle autumn and got into rest period and in this period they could be cut. In March of the next year the trees sprouted again, the annual growing period had 6 months. The difference in temperature of day and night, the annual mean tem- perature and sunshine and sunshine time were the main meteorologic factors affecting the growth of D01 Poplar.