Effects of Nitrogen Application Time on Caryopsis Development and Grain Quality of Rice Variety Yangdao 6

• Published in: Rice science Vol. 15; no. 1; pp. 57 - 62
• Main Authors: XIONG, Fei, WANG, Zhong, GU, Yun-jie, CHEN, Gang, ZHOU, Peng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2008; Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology,Yangzhou University,Yangzhou 225009,China
• Subjects: amyloplast; amylose; caryopsis development; fertilizer application time; nitrogen fertilizer; proteinoplast; rice quality; starch; 产品质量; 直链淀粉; proteinoplast; caryopsis development; nitrogen fertilizer; amylose; starch; amyloplast; fertilizer application time; rice quality
• ISSN: 1672-6308; 1876-4762
• DOI: 10.1016/S1672-6308(08)60020-7

A pot experiment was conducted to study the effects of different nitrogen application time （during the tillering or the booting stages） with the same nitrogen rates on the caryopsis development and grain quality of rice variety Yangdao 6. The increased nitrogen fertilizer （urea）, especially applied during the booting stage, could evidently increase the milled rice rate, head rice rate and protein content in rice grains compared with the control （no nitrogen application）, and decrease chalky grain rate and amylose content. Moreover, the increased nitrogen fertilizer significantly affected the caryopsis development and enhanced the grain weight when nitrogen applied during the tillering and the booting stages, especially during the booting stage. During caryopsis development the increased nitrogen fertilizer applied during the tillering and booting stages could obviously decrease the total starch and amylose contents, but not obviously for the amylopectin content in rice grain. Increased topdressing of nitrogen fertilizer, especially applied during the booting stage, had significant effect on the development and structures of amyloplasts and proteinoplasts. That is, it could change the distribution, number and shape of amyloplasts and proteinoplasts in the endosperm cells especially in grain abdomen, Compared with the control the arrangements of amyloplasts and proteinoplasts were closer, with more numbers, higher density and less interspaces each ohter. Furthermore, most amyloplasts showed polyhedron under the increased nitrogen fertilizer level.