1North-east Institute of Geography and Agroecology Chinese Academy of Sciences-130102, Changchun, China
2College of Life Sciences, Jilin Agricultural University-130118, Changchun, China
3Da′an Sodic Land Experiment Station-131317, Da′an, China
4Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
5Disease Resistant Crop Research Unit, National Institute of Agrobiological Sciences, Kannondai 2-1-2, 305–8602, Tsukuba, Japan
*e-mail: cjjiang@affrc.go.jp
#First two authors contributed equally to this study
Grain filling of rice is severely reduced under saline-alkaline conditions, resulting in loss of both grain yield and quality. Here we studied the potential improving effect of cytokinins (CKs) on grain filling of rice (Oryza sativa L.) in saline-alkaline paddy fields in the years of 2012 and 2013. The results showed that application of kinetin (KT, a synthetic CK; 10, 50 and 100 μM) to panicles significantly improved grain filling as shown by increase in 1,000-grain weight by 12.53% compared with the mock control treatment. Further, studies using opposite-paired primary rachis branches revealed that KT-application (50 μM) significantly accelerated the grain filling rate in both 2012 and 2013, and also increased the final 1,000-grain weight by 7.74% in 2013. These results demonstrate that CKapplication can significantly improve grain filling, and thus may provide a new approach to increasing grain yield and quality of rice in saline alkaline paddy field.
Cytokinins, grain filling, grain weight, rice, saline-alkaline soil
