Grain Filling Mechanisms in Spring Wheat : III. Effects of shadings on dry matter accumulation in grain and culm

Japanese Journal of Crop Science

Naoyuki TSUCHIHASHI¹  Toshihiro TAKAKU¹  Tadashi TAKAHASHI¹  Kimio NAKASEKO¹ 

关键词: Dry matter accumulation rate;    回帰分析;    Dry matter partitioning;    可溶性糖含有量;    Grain filling phase;    乾物増加速度;    Regression analysis;    乾物分配率;    Shading;    遮光;    Source activity;    ソース能力;    Spring wheat;    登熟相;    Water soluble sugar content;    春播コムギ;   

DOI  :  10.1626/jcs.63.313

学科分类：农业科学（综合）

来源: Nihon Sakumotsu Gakkai / Crop Science Society of Japan

【 摘 要 】

To determine the effects of assimilate shortage to grain filling mechanisms in spring wheat canopy (cv. Haruyutaka), we examined the accumulation and translocation of dry matter in grain, along with water soluble sugar content (WSC) and structural material in culm under shading conditions during grain filling phases. Shading treatments were conducted using 95% shading cloth from -2 to 7 days after anthesis (DAA) (initial shading), 7 to 14 DAA (early shading) and 14 to 21 DAA (late shading). These shadings prevented the wheat canopy from producing any assimilate. However rates of increase in grain dry weights for all the shadings were 50-60% of the control (no shading), while the WSC in culm was used for the grain growth. During the initial grain filling phase, the WSC in culm for the initial shading decreased (-15 mg pl-1day-1), whereas that for the control increased (20 mg pl-1day-1). The grain dry weight showed a high rate of increase (11 mg pl-1day-1) for the initial shading, being about 50% of the control (19 mg pl-1day-1). During the early phase, the WSC in culm for the early shading decreased (-15 mg pl-1day-1), although that for the control increased (12 mg pl-1day-1). The rate of grain weight increase for the early shading (24 mg pl-1dayl-1). During the late phase, the WSC in culm for the late shading decreased (-33 mg pl-1day-1) five times as much as the control (-7 mg pl-1day-1). The rate of grain weight increase for the late shading (34 mg pl-1day-1) was 60% of that for the control (55 mg pl-1day-1). Although the culm lengths at harvest were no different between the initial shading and the control, the dry weight of culm structural material for the initial shading was lower than that for the control. The difference between the cases in which the partitioning rate to grain did or did not increase is discussed herein.

【 授权许可】

Unknown