Hormones in the grains and roots in relation to post-anthesis development of inferior and superior spikelets in japonica/indica hybrid rice

Hao Zhang, Guilu Tan, Linian Yang, Jianchang Yang*, Jianhua ZHANG, Buhong Zhao

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

128 Citations (Scopus)

Abstract

Grain filling is usually not adequate in later-flowering inferior spikelets in japonica/indica (J/I) hybrid rice (Oryza sativa) although it shows stronger hybrid vigor than indica/indica (I/I) hybrid. This study investigated the potential causes by examining changes in zeatin (Z) + zeatin riboside (ZR), indole-3-acetic acid (IAA), gibberellins (GAs, GA1 + GA4), and abscisic acid (ABA) in spikelets and roots during the grain filling period. The inferior spikelets of J/I hybrid exhibited low rate of endosperm cell division and slow grain filling. During the early grain filing period, they had less Z + ZR, IAA, and ABA, but more GAs, than the earlier-flowering superior spikelets. If compared to the inferior spikelets of the I/I hybrid, the J/I inferior spikelets also had less Z + ZR, IAA, and ABA. Rates of endosperm cell division and grain filling were positively and significantly correlated with Z + ZR and ABA contents in both grains and roots or IAA in grains, whereas not significantly correlated with GAs either in grains or roots or IAA in roots. Applications of kinetin, IAA, or ABA to spikelets, or kinetin and ABA to roots, enhanced cell division and grain filling in the inferior spikelets. Results suggest that low contents of cytokinins and ABA in both grains and roots and low contents of IAA in grains may result in the poor filling of inferior spikelets in the J/I hybrid.

Original languageEnglish
Pages (from-to)195-204
Number of pages10
JournalPlant Physiology and Biochemistry
Volume47
Issue number3
DOIs
Publication statusPublished - Mar 2009

Scopus Subject Areas

  • Physiology
  • Genetics
  • Plant Science

User-Defined Keywords

  • Abscisic acid
  • Endosperm cell
  • Gibberellins
  • Grain filling
  • Indole-3-acetic acid
  • Japonica/indica hybrid rice (Oryza sativa)
  • Zeatin + zeatin riboside

Fingerprint

Dive into the research topics of 'Hormones in the grains and roots in relation to post-anthesis development of inferior and superior spikelets in japonica/indica hybrid rice'. Together they form a unique fingerprint.

Cite this