关键词: 细胞凋亡, 细胞凋亡

Abstract:

The methods of determining leaf length, leaf width, leaf area and leaf dry weight were used in seedlings of Castanopsis fissa, Michelia macclurei and Liquidambar formosana in order to understand change of their leaf shape and supply a theory basis for these seedlings culture, the correlations between leaf length and leaf width as well as between leaf area and leaf dry weight, and seasonal change of specific leaf weight (SLW) were studied in the three seedlings. The very significant correlation existed between leaf length and leaf width of the three seedlings. The month change of correlative coefficients of C. fissa and L. formosana seedlings was intimate with seasonal change, whereas that of M. macclurei seedlings was not regular. There were significant positive correlations between leaf area of young leaves and their leaf dry weight as well as between leaf area of old leaves and their leaf dry weight. The correlation between leaf dry weight and leaf area was correlative. The SLW change was great in the first half year and small in the second half year for young leaves. The SLW of young leaves was generally smaller than old leaves in the first half year, whereas it was close to that of old leaves in the second half year. Generally, the SLW of young leaf reached low values from February to April. The leaf similarity and SLW of the three seedlings varied with season change, dry matter accumulation of the leaves of seedlings increased with expansion of leaf area, and correlation between leaf dry weight and leaf area was relative with tree species and leaf age.