小麦三雌蕊品系（TP）具有3个正常雄蕊和3个可育雌蕊，一朵小花能结三粒种子。因此，TP具有一定的育种学价值，同时也是花发育研究的特异新材料。研究表明小麦三雌蕊性状是受显性核基因Pis1控制，Pis1基因位于2DL染色体上，与SSR标记Xgwm539和Xgwm349连锁。但是Pis1基因距离Xgwm539和Xgwm349较远，尚未达到精细作图的程度。本项目拟（1）开发与Pis1基因连锁的SRAP标记，并将其转化为SCAR标记；（2）利用比较基因组学的方法开发位于小麦C-2DL3-0.49区段内的饱和EST-STS标记，并筛选出与Pis1基因紧密连锁的EST-STS标记；（3）以小麦三雌蕊近等基因系群体为作图群体，利用开发出的SCAR和EST-STS标记，构建Pis1基因的精细图谱。本项目的实施可以为Pis1基因的图位克隆奠定基础。

The common wheat line three pistils (TP) has normal spike morphology but produces 3 pistils per floret, it has potential to increase grain unmber per spike. So the TP line has some breeding value and it is a new unique material for the floral development research in wheat. Genetic analysis indicated that the three pistils trait is controlled by a single dominant nuclear gene Pis1. The Pis1 gene is located on the long arm of chromosome 2D, between markers Xgwm539 and Xgwm349. But the genetic distance of the Pis1 gene is too far from Xgwm539 and Xgwm349 to meet the required level of fine map. The main work should be conducted in this program as following: (1) Find out the SRAP markers, which linkage to Pis1 gene, and convert those SRAP markers into SCAR markers. (2) Develop new EST-STS markers, which located in the deletion section of C-2DL3-0.49, based on comparative genomics analysis using wheat-Brachypodium-rice genomic colinearity. And screen out the EST-STS markers, which tightly linkage to Pis1 gene. (3) The fine genetic map of Pis1 gene should be constructed by using SCAR and EST-STS markers and the near isogentic lines populations for three pistils as mapping populations. This work set a firm base for the final cloning of Pis1 gene.