【Short Report】Grain Yield and Leaf Area Growth of Direct-Seeded Rice on Flooded and Aerobic Soils in Japan

• Main Authors: Midori Okami, Yoichiro Kato, Junko Yamagishi
• Format: Article
• Language: English
• Published: Taylor & Francis Group 2013-01-01
• Series: Plant Production Science
• Subjects: Aerobic rice; Direct-seeded rice; Grain yield; Water-saving irrigation
• Online Access: http://dx.doi.org/10.1626/pps.16.276
• ISSN: 1343-943X; 1349-1008

Direct-seeding has been proposed as a water- and labor-saving method to grow irrigated rice. Our objective was to compare the effects of flooded and aerobic conditions on the yield stability of direct-seeded rice. We set up four trials in the field: aerobic, near-saturated and flooded soils with direct seeding, and flooded soil with transplanting. Grain yield of direct-seeded rice was comparable to that of transplanted under flooded conditions. However, the yield of direct-seeded rice under aerobic conditions was up to 21% lower than that under flooded conditions. This poor performance was associated with reduced leaf growth during the vegetative stage. Our results indicate that the yield stability of direct-seeded rice could be lowered by the water-saving irrigation, compared with the conventional flooded culture. In order to save irrigation water, physiological research on direct-seeded rice should target the vulnerability of rice to aerobic soils or to soil moisture fluctuations.