水稻重要农艺性状自然变异研究进展及其应用策略

Understanding natural variations: The source of elite agronomic traits for rice breeding

水稻在长期的自然进化和人工选择过程中积累了大量自然变异,这些自然变异是许多重要农艺性状的遗传基础,也是水稻育种筛选的主要目标.近些年,随着分子技术的发展,水稻自然变异研究取得了一系列重要突破.本文结合最新研究进展,系统介绍了水稻自然变异的特点及相应分析方法,并强调了高通量测序技术在今后水稻自然变异挖掘中的意义;对最近10年来报道的抽穗期、产量元件及抗逆和驯化相关性状自然变异的分子机制及驯化特征进行了详细说明;结合这些自然变异的分子特征,总结了利用不同变异类型改良现有品种的方法,为今后分子育种提供理论依据.

As a major cereal crop worldwide, rice has undergone a long natural evolution and domestication selection, which has resulted in a large amount of sequence variations. Some variations play important roles in agronomic traits that satisfy human demands, which are usually controlled by quantitative loci. The nature of rice breeding is to select and combine beneficial variations. However, traditional breeding relies mainly on visual observation sempiricially, which is ineffective and laborious, and difficult to use natural variations. It is necessary to reveal the elite natural variations of important agronomic traits in moderrn crop breeding with molecular techniques. With the advent of molecular technology, researchers have made great progress in elucidating natural variations and the underlying molecular mechanisms in rice. In this review, we describe characteristics of natural variations and research strategies in rice, highlighting the roles of high throughput sequencing techniques. We sum the recognized molecular mechanisms controlling important agronomic rice traits, including heading data, yield elements, abiotic stress tolerance and domestication-related traits. Additionally, we discuss the strategy of using different variations in rice breeding, either by transgene technology or marker-assisted quantitative trait loci pyramiding, which would facilitate rice breeding programs with multiple superior alleles.