ALBERT

Description:    This study aims to quantify nitrogen (N) effect on occurrence of perfect rice kernel (PRK) and imperfect grains which includes white-belly rice kernel (WBRK), white-core rice kernel (WCRK), green rice kernel (GRK), opaque rice kernel (ORK), and other imperfect grains (OTHERS). Two-year field experiments involving six japonica rice cultivars and seven N treatments were performed. The structural differences between white-belly and white-core tissues were compared using scanning electron microscope. Averaged over cultivars, grain yield increased progressively with N rate. PRK increased with N rate in 2008, but decreased with increased N rate in 2009. WBRK and WCRK decreased as N rate increased for both years. High N input resulted in higher occurrence of GRK and OTHERS for both years. Most starch granules in white-belly tissues are intact and surrounded by globular protein bodies, with many air spaces between them; while in white-core tissues, starch granules are easily broken into many single granules and no protein bodies are visible. Our results suggest that N has suppressing influence on chalky grains but favorable effect on other imperfect grains, and indicate different mechanism between WBRK and WCRK. Content Type Journal Article Pages 1-12 DOI 10.1007/s11104-011-0861-4 Authors Jiangfang Qiao, College of Agronomy, Nanjing Agricultural University, Nanjing, 210095 China Zhenghui Liu, College of Agronomy, Nanjing Agricultural University, Nanjing, 210095 China Shanyu Deng, College of Agronomy, Nanjing Agricultural University, Nanjing, 210095 China Huifeng Ning, College of Agronomy, Nanjing Agricultural University, Nanjing, 210095 China Xiaoyu Yang, College of Agronomy, Nanjing Agricultural University, Nanjing, 210095 China Zhaomiao Lin, College of Agronomy, Nanjing Agricultural University, Nanjing, 210095 China Ganghua Li, College of Agronomy, Nanjing Agricultural University, Nanjing, 210095 China Qiangsheng Wang, College of Agronomy, Nanjing Agricultural University, Nanjing, 210095 China Shaohua Wang, College of Agronomy, Nanjing Agricultural University, Nanjing, 210095 China Yanfeng Ding, College of Agronomy, Nanjing Agricultural University, Nanjing, 210095 China Journal Plant and Soil Online ISSN 1573-5036 Print ISSN 0032-079X