摘要：鲜食期大豆籽粒硬度是影响菜用大豆口感品质的关键因素之一。菜用大豆籽粒硬度基因定位的研究，对于菜用大豆的生产加工和借助分子标记辅助选择育种改良菜用大豆品质具有重大意义，但目前关于鲜食期大豆籽粒硬度的研究尚未见报道。本文采用来自科丰1号×南农1138-2衍生的184份F2:7:26代重组自交家系，通过结合包含有560个多态性标记的连锁图谱对该群体大豆籽粒发育过程中的4个阶段籽粒硬度的条件与非条件QTL进行了动态分析。采用WinQTLCart V2.5软件的复合区间作图法，在6个连锁群上共定位到了11个显著影响籽粒硬度的非条件QTL，对表型变异的解释率在4.98%~12.70%之间；以基于QGAstation V2软件的条件分析方法和复合区间作图法相结合，在3个连锁群上定位了7个条件QTL，对表型变异的解释率在2.37%~16.51%之间。位于J、Da1和C2连锁群上的QTL与前人的定位结果相一致，证明了本研究定位结果的可靠性。定位区间内的L10T、Satt320和satt658可以作为有价值的分子标记，提高分子标记辅助选择的效率。本研究同时对条件和非条件QTL进行鉴定，将加深对菜用大豆籽粒硬度相关QTL的发育动态的理解；通过比较分析大豆籽粒发育的特定阶段硬度相关的条件与非条件QTL，为进一步精细定位菜用大豆籽粒硬度相关基因以及探索硬度发育遗传机理提供分子依据。

关键词：菜用大豆，硬度，品质，条件和非条件QTL

Conditional and Unconditional QTL Mapping For Seed Hardness of Vegetable Soybean

Abstract：The seed hardness of soybean in fresh period is one of the key factors that affect the taste quality of soybean. Gene mapping of seed hardness of vegetable soybean research is of great significance for the production and processing. Moreover, the determined genes or molecular markers would play a crucial part in marker-assisted selection (MAS) breeding for the improvement of vegetable soybean taste quality. However, the related research on gene mapping of fresh period soybean seed hardness has not been reported as known. In this paper, based on the genetic linkage map, which including 560 polymorphism markers and was constructed using 184 F2:7:26 recombinant inbred line (RIL) population derived from a cross between two cultivars Kefeng 1 and Nannong1138-2, unconditional and conditional QTL mapping were conducted for seed hardness during the development of soybean. 11 unconditional QTLs (namely conventional QTL) underlying seed hardness were detected on 6 linkage groups (LG) using the composite interval mapping (CIM) method in WinQTLCart V2.5 software. The phenotypic variation explained (PVE) by these unconditional QTLs ranged from 4.98% to 12.70%. 7 condition QTLs were mapped on 3 LGs combining the conditional analysis in QGAstation V2 software and the CIM method. The PVE was between 2.37% and 16.51%. These QTLs located on J, Da1 and C2 linkage group were consistent with the previous reports about cooked soybean seed hardness, indicating the reliability of the current results. Markers derived from those confidence interval of QTLs , namely L10T, Satt320 and satt658, will further improve the efficiency of marker assisted selection (MAS) in breeding program. The identification of both conditional and unconditional QTL is valuable to understand the developmental behavior of QTL underlying vegetable soybean seed hardness. The comparative analysis of conditional and unconditional QTLs provides a molecular basis for fine mapping the causal gene and exploring the genetic mechanism of vegetable soybean seed hardness.

Key words: vegetable soybean, seed hardness, quality, conditional and unconditional QTL

目  录

摘要3

关键词3

Abstract3

Key words3

引言4

1.1菜用大豆籽粒硬度研究概述4

1.2条件与非条件QTL研究概述4

1材料与方法5

1.1实验材料与遗传图谱 5