洞庭湖区11个杨树新无性系的生长差异

为选择出更多适合在洞庭湖区造林的优良杨树无性系,对引进的11个杨树新无性系与南林-95和南林-895在洞庭湖区进行了造林对比试验.对7年生杨树无性系的生长量分析结果表明:11个无性系中,有4-6、7-40、1-20、7-45、2-2无性系胸径、树高、单株材积生长量超过了南林-95和南林-895.其中无性系4-6最具生长...

Growth Variation of Eleven New Poplar Clones in Dongting Lake Area, Hunan

An afforestation comparison test was conducted between eleven new poplar clones and NL-95 and NL-895 in order to select more superior poplar clones suitable for afforestation in Dongting Lake area.The growth of the 7-year-old poplar clones showed that,among the eleven clones,diameter at breast height(DBH),tree height,volume increment of five clones 4-6,7-40,1-20,7-45 and 2-2 were higher than those of NL-95 and NL-895.The DBH,tree height,volume increment of the clone 4-6 were 30.4 cm,25.0 m and 0.695 6 m3,respectively.Compared with NL-95 and NL-895,the volume increment of the cone 4-6 increased by 51.0% and 55.8%,respectively.The clone 4-6 exhibited the best growth status,followed by four clones 7-40,1-20,7-45 and 2-2.There were no significant differences in DBH and vo-lume increment between the clone 4-6 and the four clones 7-40,1-20,7-45 and 2-2;however,there were significant or highly significant differences between the cone 4-6 and the rest clones.The volume increments of four clones 4-6,7-40,1-20,and 7-45 increased by more than 15% compared with those of NL-95 and NL-895.The four clones 4-6,7-40,1-20,and 7-45 have great growth advantage in Dongting Lake area,and they all exhibit fast growth in the early stages.