Characteristics of Dry Matter Production Process in High Yielding Rice Varieties : II. Comparisons among two early and three medium varieties

Japanese Journal of Crop Science

Hiroyuki SHIMODA¹  Kuni ISHIHARA¹  Kuniyuki SAITOH¹ 

关键词: Dry matter production;    イネ;    Growth analysis;    乾物生産;    High yielding variety;    吸光係数;    Light intercepting characteristics;    生長解析;    Light extinction coefficient;    受光態勢;    Rice plant;    多収性品種;   

DOI  :  10.1626/jcs.59.303

学科分类：农业科学（综合）

来源: Nihon Sakumotsu Gakkai / Crop Science Society of Japan

【 摘 要 】

In order to clarify eco-physiological characteristics of high yielding rice varieties, two early varieties; Akihikari (Japanese cultivar) and Nanjing 11 (Chinese cultivar, Indica), and three medium varieties; Nippon-bare, Musasikogane (Japanese cultivars) and Milyang 23 (Korean cultivar, Japonica/Indica hybrid) were cultivated in 1985 and 1986. Both yield and dry matter production were higher in Nanjing 11 than those in Akihikari, and in Milyang 23 and Musasikogane than those in Nipponbare. These high dry matter production were due to high crop growth rates before heading time in the early varieties, and after heading time in the medium varieties. At the panicle development stage, every variety had erect foliage with small light extinction coefficients. At the early ripening stage, however, the coefficients increased remarkably in Akihikari and Nipponbare as compared with those in the other varieties owing to the increase of horizontal leaves and mutural shading effect of ears on the canopy. Increase in net assimilation rate by the thinning treatment (the planting density was reduced to half of control) at the early ripening stage was remarkably higher in Akihikari than that in Nanjing 11, and that in Nipponbare was higher than that in Milyang 23 and Musasikogane. These results indicate that Akihikari and Nipponbare canopies were changed into an unfavorable light intercepting structure after heading time. It became clear from these results that higher dry matter production of Nanjing 11 than that of Akihikari was mainly due to larger leaf area index before heading time, and that higher dry matter production of Milyang 23 and Musasikogane than that of Nipponbare was due to the differences in light intercepting characteristics of the canopy after heading time.

【 授权许可】

Unknown