黔西南光皮桦种源早期选择

以前期收集的西南地区12个种源为材料,在黔西南进行光皮桦种源选择试验.结果表明:光皮桦不同林龄的树高和地径在种源间和种源内家系间均存在显著或极显著差异,而且各生长性状在种源内变异高于种源间变异.不同林龄树高和地径间均存在显著相关,8个月生光皮桦生长性状与种源地气候和地理因子相关性不显著,而20个月生树高、地径均与经度存在显著正相关,树高与海拔显著负相关,地径与年均降水量显著正相关.综合不同种源各时期生长表现以及生长性状问的相关性,以20个月生树高为主要因子,初步选择出适合在黔西南发展的3个优良种源,即1号(广西田林)、2号(广西隆林)和3号种源(广西融水).研究结果可为黔西南以及周边类似地区发展光皮桦人工林提供科学依据.

Earlier Provenance Selection of Betula luminifera in South-west Part of Guizhou Province,China

In this paper,growth performance of 12 provenances of Betula luminifera from five provinces in south-west China were investigated when 8 and 20 month old,to study their genetic variation and preliminarily select prior provenances of this species in south-west part of Guizhou Province.The result showed that there existed significant differences among and within provenances for height and base diameter at the two ages,and growth variations within provenances were much higher than those among provenances.Heights were in significant positive correlation with base diameter at both ages.No significant relationship were found between growth traits and climate and geographic factors of provenance localities when 8 month old,while at age of 20 month,height and base diameter were in positively significant correlation with longitude,height negatively significantly correlated to altitude,and base diameter positively to mean annual rainfall.Three prior provenances,all from Guangxi,were preliminarily screen out mainly based on height at age of 20 month,which were suitable to develop in southwest parts of Guizhou.These findings will be contributed to further breeding studies and plantation development of this species in southwest parts of Guizhou and surrounding areas with similar environment.