产量和品质是农作物最重要的农艺性状。以水稻为模式，科学家们对产量性状有较多的研究，而对稻米品质的研究相对滞后，其重要原因之一是决定品质性状的遗传网络复杂。而对于决定稻米食用和蒸煮品质这一重要性状而言，在定量测定指标上也存在很大的困难。因此，对决定稻米食用和蒸煮品质的分子机理长期以来不甚明了。
中科院遗传与发育生物学研究所植物基因研究中心李家洋院士课题组与中国水稻研究所钱前课题组、扬州大学顾铭洪课题组及美国堪萨斯州立大学余建明教授合作，经过长达7年的研究，为解决这一重要问题取得了突破性进展。相关结果发表在权威期刊美国《国家科学院院刊》（Proceedings of the National Academy of Sciences USA）上。
稻米的食用和蒸煮品质主要由直链淀粉含量、胶稠度、糊化温度以及三者之间的互作而决定。李家洋等通过关联分析等手段对淀粉生物合成途径中18个基因的系统研究发现上述基因之间的互作关系，揭示了直链淀粉含量、胶稠度、糊化温度的相关性、决定这3个性状的主效基因和微效基因及它们之间的作用关系，从而揭示了调控稻米食用和蒸煮品质的精细调控网络。这一模型得到了遗传转化（转基因）实验的证实。
这项研究的结果为稻米品质的分子设计与遗传改良提供了理论依据。
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《国家科学院院刊》发表论文摘要（英文）
Allelic diversities in rice starch biosynthesis lead to a diverse array of rice eating and cooking qualities
Zhixi Tiana,1,2, Qian Qianb,1, Qiaoquan Liuc,1, Meixian Yanb, Xinfang Liua, Changjie Yanc, Guifu Liua, Zhenyu Gaob, Shuzhu Tangc, Dali Zengb, Yonghong Wanga, Jianming Yud,3, Minghong Guc,3 and Jiayang Lia,3
Abstract
More than half of the world's population uses rice as a source of carbon intake every day. Improving grain quality is thus essential to rice consumers. The three main properties that determine rice eating and cooking quality―amylose content, gel consistency, and gelatinization temperature―correlate with one another, but the underlying mechanism of these properties remains unclear. Through an association analysis approach, we found that genes related to starch synthesis cooperate with each other to form a fine regulating network that controls the eating and cooking quality and defines the correlation among these three properties. Genetic transformation results verified the association findings and also suggested the possibility of developing elite cultivars through modification with selected major and/or minor starch synthesis-related genes.
