Plant architecture determines grain production in rice(Oryza sativa) and is affected by important agronomic traits such as tillering,plant height,and panicle morphology.Many key genes involved in controlling the initi...Plant architecture determines grain production in rice(Oryza sativa) and is affected by important agronomic traits such as tillering,plant height,and panicle morphology.Many key genes involved in controlling the initiation and outgrowth of axillary buds,the elongation of stems,and the architecture of inflorescences have been isolated and analyzed.Previous studies have shown that SiPf40,which was identified from a foxtail millet(Setaria italica) immature seed cDNA library,causes extra branches and tillers in SiPf40-transgenic tobacco and foxtail millet,respectively.To reconfirm its function,we generated transgenic rice plants overexpressing SiPf40 under the control of the ubiquitin promoter.SiPf40-overexpressing transgenic plants have a greater tillering number and a wider tiller angle than wild-type plants.Their root architecture is modified by the promotion of lateral root development,and the distribution of xylem and phloem in the vascular bundle is affected.Analysis of hormone levels showed that the ratios of indole-3-acetic acid/zeatin(IAA/ZR) and IAA/gibberellic acid(IAA/GA) decreased in SiPf40-transgenic plants compared with wild-type plants.These findings strongly suggest that SiPf40 plays an important role in plant architecture.展开更多
基金supported by the National Transgenic Major Program of China (Grant Nos. 2008ZX003-002 and 2009ZX08009-093B)the National High-Tech Research and Development Program of China (Grant No.2008AA10Z158-2)+1 种基金the National Natural Science Foundation of China (Grant Nos. 30971555 and 30671124)and the State Key Laboratory for Agrobiotechnology in China (Grant No. 2010SKLAB05-12)
文摘Plant architecture determines grain production in rice(Oryza sativa) and is affected by important agronomic traits such as tillering,plant height,and panicle morphology.Many key genes involved in controlling the initiation and outgrowth of axillary buds,the elongation of stems,and the architecture of inflorescences have been isolated and analyzed.Previous studies have shown that SiPf40,which was identified from a foxtail millet(Setaria italica) immature seed cDNA library,causes extra branches and tillers in SiPf40-transgenic tobacco and foxtail millet,respectively.To reconfirm its function,we generated transgenic rice plants overexpressing SiPf40 under the control of the ubiquitin promoter.SiPf40-overexpressing transgenic plants have a greater tillering number and a wider tiller angle than wild-type plants.Their root architecture is modified by the promotion of lateral root development,and the distribution of xylem and phloem in the vascular bundle is affected.Analysis of hormone levels showed that the ratios of indole-3-acetic acid/zeatin(IAA/ZR) and IAA/gibberellic acid(IAA/GA) decreased in SiPf40-transgenic plants compared with wild-type plants.These findings strongly suggest that SiPf40 plays an important role in plant architecture.
