Leaf Emergence Rate and Temperature in Early and Late Spring Wheat Varieties

Japanese Journal of Crop Science

Tadashi TAKAHASHI¹  Kimio NAKASEKO¹ 

关键词: Accumulated temperature;    回帰直線;    Double ridge stage;    出葉速度;    Leaf emergence rate;    出葉展開度;    Leaf expanding degree;    積算気温;    Regression line;    播種期;    Sowing time;    春播コムギ品種;    Spring wheat variety;    幼穂分化期;   

DOI  :  10.1626/jcs.63.81

学科分类：农业科学（综合）

来源: Nihon Sakumotsu Gakkai / Crop Science Society of Japan

【 摘 要 】

Spring wheat varieties, early Haruyutaka and late Selpek, were grown under field conditions to find the relation between leaf emergence rate and temperature. Fourteen sowings were made at two week intervals from March 17 (S1) to September 13 (S14). Leaf expanding degree (Haun's scale) were measured daily, and shoot apices were checked every day to determine the date double ridge stage (DRS) appeared. Final leaf numbers differed by only one, although the first nine sowings ranged over four months from March (S1) to July (S9). Late variety Selpek always had one more leaf than early variety Haruyutaka for S1∼S9, suggesting that the final number of leaves was closely related to the earlobes of varieties. Leaf emergence rates with accumulated temperature (AT) were higher before than after DRS, and those before DRS decreased with delay in sowing time. The leaf expanding degree at DRS did not vary greatly among sowing times, but were synchronized with phenology. We established regressions before and after DRS for the relation between leaf expanding degree and AT. The coefficients (a) before DRS were higher than those after DRS for both varieties. In addition, their standard deviation was large so that inclinations of regressions before DRS differed with sowing time. We concluded that leaf emergence rate has a squared relation with mean temperature before DRS and a linear relation with mean temperature after DRS.

【 授权许可】

Unknown