水稻花序结构调控机制研究进展

Research Progress in Regulation Mechanism of Rice Inflorescence Structure

禾本科作物的花序结构直接影响穗粒数和最终产量,其多样性主要依赖于分枝模式和花的位置。水稻作为研究禾本科作物的模式植物,有关花序结构的调控机制已取得重大进展,对花序发育调控因素的概述,将有助于水稻穗型的遗传改良和高产育种。水稻花序发育始于顶端分生组织向花序分生组织转变,之后生成花序轴分生组织、一次枝梗分生组织、二次枝梗分生组织、小穗分生组织和小花分生组织。花序相关分生组织受到众多基因调控,形成一个复杂的遗传网络,发育过程中任一节点发生变化都会导致穗型发生变化。在改良过程中,调控影响花序发育基因的时空表达,组合相关优异等位基因,更有利于优化水稻穗型;在驯化过程中,穗型受到选择,水稻花序结构调整为更有利于增加小穗数量的结构。有关水稻花序发育影响因子的研究,将有利于穗型遗传改良,并为分子设计育种提供理论支撑。对影响水稻花序发育过程中各因子进行梳理,并对其在调控花序结构过程中的路径进行概括,水稻作为模式作物对其花序结构遗传调控网络的研究,为禾本科作物花序发育研究提供重要参考。

The inflorescence structure of cereal crops influences the number of grains per plant and grain yield directly,and its diversity mainly depends on branching pattern and flower location.Great progress has been made in the regulation mechanism of inflorescence structure in rice,a model plant of the major cereal crops.An overview of the regulatory factors of inflorescence development will be helpful for genetic improvement of rice panicle architecture and high-yield breeding.The development of rice inflorescence begins with the transition from shoot apical meristem to inflorescence meristem,and then rachis meristem,primary branch meristem,secondary branch meristem,spikelet meristem and floret meristem generate sequentially.Inflorescence-related meristems are regulated by a great number of genes,forming a complex genetic network.Changes in any link during the inflorescence development can alter the panicle architecture.Regulating the spatiotemporal expression of genes affecting inflorescence development and combining related excellent alleles are more conducive to optimizing rice panicle architecture in the improvement process.The panicle architecture is selected and modified to increase the number of spikelets during rice domestication.Therefore,the research on the factors affecting rice inflorescence development will be beneficial to the genetic improvement of rice panicle architecture and provide theoretical support for molecular design breeding.In the study,the factors affecting the development of rice inflorescence are listed,and the paths of these factors in the process of regulating inflorescence structure are summarized.The study of the genetic regulatory network of inflorescence structure in rice as a model crop will provide an important reference for studying the inflorescence development in other cereals.