Hormonal Regulation of Grain Filling in Rice through Foliar Application of Nutrients and Growth Promoters

Abstract

A rapid increase of grain weight after flowering and fertilization in rice plants is closely related to the level of endogenous plant hormones. There is a rapid increase in grain weight after fertilization, suggesting that endogenous plant hormones play an important role in increasing grain filling and rate of rice. The rates of cell division and grain filling are not only correlated with the levels of ABA and ethylene, but are also correlated with the ratio of ABA to ACC in grains. Hence, a study was conducted at the Department of Rice, Tamil Nadu Agricultural University, Coimbatore during Kharif season with nine treatments in three different rice genotypes (ADT (R) 49, Rice CO 52 and CO (R) 50). In our study, ABA concentration was higher in the superior grains of the genotype rice CO 52 (38.0 ng. g-1) than the genotype ADT (R) 49 and the low ABA concentration was observed in the control in both the genotypes. Similarly, the ethylene concentration was high under control in the inferior grains of the rice genotypes ADT (R) 49 - 0.053 nmol. g-1 DW (dry weight) h-1and Rice CO 52 - 0.042 nmol. g-1 DW h-1than the treated plants. To conclude, the hormone ethylene and ABA contents in superior and inferior grains of current study had shown the ABA concentration is higher in the superior grains than the inferior grains and the ethylene concentration was also higher in the inferior grains than the superior grains. ABA application promoted endosperm growth by improving the assimilate partitioning to filling of grains.

DOI

https://doi.org/10.29321/MAJ.2018.000182

Pages

460 - 462

Creative Commons

Copyright

© The Author(s), 2026. Published by Madras Agricultural Students' Union in Madras Agricultural Journal (MAJ). This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited by the user.

Keywords