The Influence of Sowing Time on Dry Matter Partitioning in Spring Wheat

Japanese Journal of Crop Science

Tadashi TAKAHASHI¹  Kimio NAKASEKO¹ 

关键词: Developmental index;    回帰式;    Dry matter partitioning;    乾物分配率;    Growth phase;    生育相;    Regression formula;    播種期;    Sowing time;    発育指数;    Spring wheat.;    春播コムギ.;   

DOI  :  10.1626/jcs.62.88

学科分类：农业科学（综合）

来源: Nihon Sakumotsu Gakkai / Crop Science Society of Japan

【 摘 要 】

To evaluate the response of sowing time on partitionings to leaf blade, ear and grain in spring wheat, the regression formulas for these partitionings against days after emergence and developmental index were calculated in four growth phases. Data was from a field experiment with three sowing times at two week intervals for three varieties. In growth phase I, from emergence to double ridge stage, the partitioning to leaf blades, Yl, was evaluated by the regression formulas, Yl1=b1X+c1 against days after emergence (X) and Yl1=B1X+C1 against developmental index (X). The coefficient b1 was higher with later sowing time. Shortening of this phase duration with later sowing did not cause this increase of b1, because the coefficient B1 was also higher with later sowing. In growth phase II, from double ridge stage to flag leaf emergence, the partitioning to leaf blades, Yl, was evaluated by regression formulas, Yl2=-b2X+c2 against days after emergence and Yl2=-B2X+C2 against developmental index. The coefficient b2 was lowest with early sowing for all varieties. Long duration of this phase with early sowing resulted low b2 value, because the coefficient B2 showed a different tendency with b2. In growth phase III, from flag leaf emergence to anthesis, the partitioning to ear, Ye, was evaluated by regression formulas, Ye=-a3(X-b3)2+c3 against days after emergence and Ye=-A3(X-B3)2+C3 against developmental index. As sowing time was later, the shape of the regression curve was narrower and more acute because of secondary coefficient a3 and higher constant c3. This difference in shape of the regression curve was not due to a difference in phase duration, because the coefficient A3 and the constant C3 were highest with late sowing, in contrast to a3 and c3. In growth phase IV, from anthesis to milk ripe stage, the partitioning to grains, Yg, was evaluated by a regression formula against days after emergence, Yg=b4X-c4. However this regression did not fit this relation, because the correlation coefficients were low. The results indicated that grain has a fixed growth rate, while the increase rate of culm reserved material altered depending on the influence of radiation.

【 授权许可】

Unknown