奥地利黑松的生长特性及抗寒性研究

该文通过育苗、造林试验和实验室测定，研究了奥地利黑松的生长特性及抗寒性.结果表明:奥地利黑松幼苗根系发达，主根长、侧根粗壮、层次明显，鲜质量大，与乡土树种油松形成鲜明对照.苗木地径生长量显著大于油松；高生长较快的季节出现在6月下旬至8月下旬，生长量占全年总量的42.3%.31年生奥地利黑松的高生长速生期出现在第15～20年，生长量占树高的32.1%.与油松相比，奥地利黑松树高生长较慢，胸径大于油松，材积年生长量0.007 4 m3,是油松的2倍.人工冷冻处理，测定针叶组织的电解质渗出率，在-20～-40℃条件下，奥地利黑松电解质渗出率明显大于油松；用拟合的Logistic测算出组织的半致死温度（LT50），奥地利黑松的LT50为-16.2 ℃，油松的LT50为-17.9 ℃，其抗寒性比油松弱.针叶组织中较低的束缚水含量、K+含量、类胡萝卜素含量、ABA含量是奥地利黑松抗寒性弱的主要原因. 

Growth characteristics and cold resistance of Pinus nigra var. austriaca

This paper deals with the growth characteristics and the related index of its cold resistance of Pinus nigra var. austriaca on the basis of the field investigation and experimental measurement. The results showed that young seedlings of P. nigra var. austriaca had a strong root system, long vertical roots, thick lateral roots, distinct structure, and a heavy fresh mass, a striking contrast with seedlings of P. tabulaeformis. The diameter growth of the one year old seedlings was obviously bigger than that of P. tabulaeformis. The fast growth period of height of seedlings occurred from late June to the late of August, with growth increment accounting for 42.3% of total one. Fast height growth period of 31 year old P. nigra var. austriaca occurred during the 15-20th year, with the growth increment accounting for 32.1% of total. The height growth of P. nigra var. austriaca was slower than that of P. tabulaeformis, while the diameter growth was bigger than that of P. tabulaeformis, with an average annual volume growth of 0.007 4 m³, which is one time larger than that of P. tabulaeformis. The measurement of cold resistance showed that the exudation rate of electrolyte of P. nigra var. austriaca was higher than that of P. tabulaeformis at –20--40℃, the tissue’s median lethal temperature (LT50) of it was at –16.2℃, while that of P. tabulaeformis was at –17.9℃. The cold resistance of P. nigra var. austriaca was weaker than that of P. tabulaeformis. The relative low content of bound water, K+, carotenoid and ABA in the leaf tissue of P. nigra var. austriaca is the internal cause of its weak cold resistance.