Effects of Canopy Light Distribution Characteristics and Leaf Nitrogen Content on Efficiency of Radiation Use in Dry Matter Accumulation of Soybean Cultivars

Japanese Journal of Crop Science

Ayako SAKAI¹  Shingo TAKA¹  Ushio HASHIKAWA¹  Tatsuhiko SHIRAIWA¹ 

关键词: Dry matter production;    SLW;    Leaf nitrogen content;    乾物生産;    Light extinction coefficient;    吸光係数;    Radiation conversion efficiency;    ダイズ;    光エネルギー変換効率;    Soybean;    品種間差異;    Varietal difference;    葉身窒素濃度;   

DOI  :  10.1626/jcs.63.1

学科分类：农业科学（综合）

来源: Nihon Sakumotsu Gakkai / Crop Science Society of Japan

【 摘 要 】

The amount of dry matter produced per photosynthetically active radiation (PAR) intercepted by the canopy (EPAR) and factors which might affect EPAR were determined for various soybean cultivars, and their relationships were also analyzed in two field experiments. In 1989 and 1990, 11 cultivars and 27 cultivars respectively, were grown on an experimental field in Shiga Prefectural Junior College. Changes of intercepted PAR, top dry matter weight, light extinction coefficient (KPAR), nitrogen content per leaf area (SLN) and nitrogen accumulation in the top (1990 only) were measured. EPAR averaged for all the cultivars was 2.48g MJ-1 in both years and its coefficient of variance among cultivars was ±9% in 1989 and ±17% in 1990. In general, recent cultivars showed greater EPAR than older ones. The correlation coefficients between SLN and EPAR were 0.548 in 1989 and 0.651 in 1990, while there was no correlation between KPAR and EPAR. Since SLN showed close correlation with SLW (r=0.954 in 1989, r=0.710 in 1990), the difference in EPAR between old and new cultivars was considered to be attributable mainly to the improved leaf morphological trait and consequently greater leaf photosynthesis of newer cultivars. SLN further correlated with total top nitrogen content (r=0.736 in 1990) thus seemed to be limited by nitrogen accumulation.

【 授权许可】

Unknown