水稻直播相关性状遗传分析及分子机制研究进展

Research Progress in Genetic Analysis and Molecular Mechanisms of Rice Direct-seeding Related Traits

推广应用直播稻以替代水稻传统育苗移栽的栽培方式,是解决经济效益低、水资源浪费、温室气体排放严重等目前水稻产业面临的一系列严重问题的有效方法。近年来我国直播稻推广迅速,但限制直播稻推广的诸多关键制约因素,如杂草难以控制、直播出苗率低、出苗不整齐、倒伏等问题尚未有效解决。选育早期活力强、耐厌氧和低温发芽、抗倒伏的水稻品种,是解决水稻直播关键制约因素的材料基础。水稻基因库中存在大量相关优异性状和功能基因,鉴定和应用这些功能基因,通过现代分子育种技术培育适应直播的水稻品种,是突破目前直播稻推广和应用瓶颈的关键。但长期以来水稻育种是围绕移栽的种植方式进行的,大量直播相关性状的优异功能基因在现代品种中已经丢失。因此必须利用现代基因组学技术,从更广泛的多样性种质资源中挖掘优异功能基因,剖析控制相关性状的分子调控机制,加快推进精准选育适应直播的水稻品种进程。围绕目前水稻直播亟需解决的早期生长活力、厌氧发芽、低温发芽以及抗倒伏性状,综述了这些性状目前在种质资源挖掘、性状遗传分析、功能基因克隆和分子机制研究等方面的进展,展望了这些研究进展在相关性状改良和适合直播水稻品种选育方面的应用前景,为水稻直播相关性状的基础理论研究和育种应用研究提供参考。

Replacement of traditional puddled transplanted rice(PTR)by direct-seed rice(DSR)is an effective method to solve the problems of the rice industry,including low economic benefit,waste of water resources,and serious greenhouse gas emission.Though DSR has been rapidly promoted in China in recent years,many restraints in DSR remained unsolved,such as weed management,seedling emergence rate,and lodging.Breeding of rice with high early seedling vigor,ability to germinate at low oxygen and temperature environment,and lodging resistance,is the base of materials for DSR.Rice gene pools contain a lot of resources and functional genes that can solve these problems.Characterizing and utilizing these resources and genes to breed rice varieties suitable for DSR is the key to DSR promotion.However,while most of the modern rice varieties were bred for PTR,many genes related to DSR desired traits were lost in modern varieties.More diverse germplasm and nodern genomics techniques are needed to identify functional genes and underlying molecular mechanisms for DSR desired traits,to speed up the breeding process of varieties suitable for DSR.In this review,we summarized the progress on resources identification,genetic analysis,functional gene cloning,and molecular mechanisms dissecting of key traits related to DSR,including early seedling vigor,ability to germinate under low oxygen and temperature,and lodging resistance.We also prospected the utilization of these results in DSR related traits improvement,as well as breeding of varieties suitable for DSR.This review may provide a valuable reference for basic theoretical research and breeding application researche of rice directseeding-related traits.