泡桐无性系苗期昼夜生长节律的研究

通过对7个泡桐无性系苗期昼夜生长节律的研究,发现影响泡桐茎伸长速率的主要气象因子,早期与中期是气温和相对湿度,晚期是气温和光照;影响叶面积增长速率的主要气象因子,早期是相对湿度、气温和光照,中、晚期是气温和光照。叶面积增长速率、茎伸长速率在昼夜间呈双峰分布,高峰随生长时期而变化,主要分布在18:00-24:00和12:00-18:00时间区段内。不同无性系有不同的叶面积增长速率、茎伸长速率的变化类型。

STUDY ON THE DIURNAL GROWTH RHYTHM OF PAULOWNIA CLONES

Diurnal growth rates of stem elongation and leaf area of 7 1-year-old paulownia clones, were observed at early growth stage (June 15th-18th),middle growth stage (August 2nd-4th) and late growth stage(August 28th-31th,1991) respectively in the nursery of Yenzhou county,Shandong province.The results show that the major meteorological factors affecting the stemelongation growth rate were arranged the following sequence: relative humi-dity and temperature in early and middle stage, temperature and illuminationin late stage, affecting the growth rate of leaf area were relation humidity,temperature and illumination in early stage, temperature and illumination inboth middle and late stage. The peak values of both stem elongation and leafarea growth rate are double-peak curves. Their peak values appear at 18:00-24:00 and 12:00-18:00 respectiveiy. Each of the 7 clones has a differentdiural and seasonal growth rhythm, based on which, they may be classifiedinto several different growth types. The results of ths research provide method and basis for the comparative study on the ecological and physiological characterisics of Paulownia genus.