【作者】 叶石；

【导师】 张晓科；

【作者基本信息】 西北农林科技大学 ， 种子工程， 2010， 硕士

【摘要】 小麦籽粒多酚氧化酶(PPO)活性和黄色素(YP)含量是影响小麦面粉白度的两个重要因素。小麦是陕西省主要的粮食作物,在生产上占据了重要地位。本研究利用功能标记PPO16、PPO18、PPO29、YP7A、YP7A-2、YP7B-1、YP7B-2、YP7B-3,对184份陕西小麦品种(系)籽粒内控制PPO活性(Ppo-A1和Ppo-B1位点)和YP含量(Psy-A1和Psy-A1)主效基因位点的等位变异进行检测,并对其分布特点进行分析。获得的研究结果如下:1.总体来讲,在陕西小麦品种(系)中,两个控制籽粒PPO活性基因位点的等位变异平均分布比例不同。在Ppo-A1位点,存在两种等位变异类型Ppo-A1a和Ppo-A1b,平均比例分别为42.9%和57.1%;在Ppo-D1位点,也存在两种等位变异类型,即Ppo-D1a和Ppo-D1b,平均分别占32.6%和67.4%。两个位点存在4种等位变异组成类型,其平均比例大小不同;存在等位变异组合类型Ppo-A1a/Ppo-D1a(较高PPO活性)、Ppo-A1a/Ppo-D1b(最高PPO活性)、Ppo-A1b/ Ppo-D1a(最低PPO活性)和Ppo-A1b/ Ppo-D1b (较低PPO活性),所占品种(系)的平均频率依次为11.4 %、31.5%、21.2%和35.9%。2.在陕西各个麦区,控制PPO活性基因的组合的分布比例也不同。在陕西关中小麦品种(系)中,4种组合类型比例变化趋势与全省品种的总体变化趋势一致;渭北旱塬品种(系) 4种组合频率大小顺序为: Ppo-A1a/Ppo-D1b>Ppo- A1b/Ppo-D1a >Ppo-A1a/Ppo-D1a>Ppo-A1b/Ppo-D1b;陕南品种(系)4种组合比例大小依次为:Ppo-A1b/Ppo-D1b>Ppo-A1a/Ppo-D1b>Ppo-A1b/Ppo-D1a>Ppo-A1a/Ppo-D1a。3.总体来看,陕西小麦籽粒内低PPO活性的品种(系)所占的比例偏低,选育低PPO活性品种成为当前陕西小麦品质改良的主要目标之一。4.在陕西小麦品种(系)中,控制籽粒YP含量的两个主效基因位点组成的平均比例也存在差异。在Psy-A1位点,存在2种等位变异,即Psy-A1a和Psy-A1b,品种(系)平均比例分别为50.5%和49.5%,没有发现含Psy-A1c等位变异品种(系);在Psy-B1位点,存在3种等位变异,其中以Psy-B1b为主(62.5%),Psy-B1a次之(29.6%),Psy-B1c较少(7.6%),没有发现含Psy-B1d等位变异品种(系)。两位点存在6种等位变异组合类型,但平均分布比例不同;Psy-A1b/Psy-B1b组合类型所占的比例最高,为37.5%;其次是Psy-A1a/Psy-B1b组合类型,为25%;组合Psy-A1a/Psy-B1a(19.6%)和Psy-A1b/Psy-B1a(10.3%)比例较低,以Psy-A1b/Psy-B1c(1.6%)和Psy-A1a/Psy-B1c(6%)所占的比例最低。5.在陕西各个麦区,控制籽粒YP含量基因的组合类型的分布比例不同。在关中地区小麦品种(系),存在6种组合类型,其比例大小顺序为:Psy-A1b/Psy-B1b>Psy-A1a/Psy-B1b > Psy-A1a/Psy-B1a > Psy-A1a/Psy-B1c=Psy-A1b/Psy-B1a > Psy- A1b/Psy-B1c,不存在组合类型Psy-A1a/Psy-B1c;在渭北旱塬地区品种(系)中,存在5种组合类型,其比例大小顺序为:Psy-A1a/Psy-B1a>Psy-A1a/Psy-B1b=Psy-A1b/Psy-B1a= Psy-A1b/Psy-B1b>Psy-A1a/Psy-B1c,不存在组合类型Psy-A1b/Psy-B1c;在陕南地区小麦也存在5种组合类型,而比例大小顺序为:Psy-A1b/Psy-B1b>Psy-A1a/Psy-B1b>Psy-A1b/Psy-B1a > Psy-A1a/Psy-B1a > Psy-A1a/Psy-B1c ,也不存在组合类型Psy-A1b/Psy-B1c。6.总体来看,陕西小麦品种(系)中低黄色素含量的等位变异类型所占的比例较高。陕西不同地区育种目标和种植要求的差异,造成了不同地区小麦品种黄色素含量基因组成的不同。本研究利用8个功能分子标记,首次系统检测了陕西小麦品种(系)籽粒中控制PPO活性和YP含量4个主效基因位点的等位变异组成,并对其分布进行了分析。依据基因组成与籽粒内PPO活性和YP含量表型关系,预测和评价了陕西小麦品种(系)籽粒内PPO活性和YP含量的高低,为以后陕西小麦品质育种提供了依据。更多还原

【Abstract】 The PPO activity and Yellow Pigment content are two important factors influencing wheat flour whiteness. Wheat is the main food crops in Shaanxi Province, and it occupied an important position in the production. In order to investigate and analysis the distribution of allelic variations for genes Ppo-A1、Ppo-D1、Psy-A1 and Psy-B1 in Shaanxi winter wheat, functional molecular markers PPO16、PPO18、PPO29、YP7A、YP7A-2、YP7B-1 and YP7B-2 were used to detect 184 wheat cultivars released in Shaanxi.1. The proportion of genotype controlling PPO activity at PPO-A1 and Ppo-B1 loci were different in Shaanxi wheat cultivars. Two allelic variations at Ppo-A1 locus were found in Shaanxi wheat cultivars, Ppo-A1a and Ppo-A1b alleles, respectively. The frequencies of alleles Ppo-A1a and Ppo-A1b were 42.9% and 57.1%, respectively. Ppo-D1a and Ppo-D1b at Ppo-D1 locus were 32.6% and 67.4 %, respectively. The frequencies of allelic combinations of PPO genes for Ppo-A1a/Ppo-D1a (higher PPO activity)、Ppo-A1a/Ppo-D1b (the highest PPO activity), Ppo-A1b/Ppo-D1a (the lowest PPO activity) and Ppo-A1b/Ppo-D1b (lower PPO activity) at Ppo-A1 and Ppo-D1 loci were 11.4%、31.5%、21.2% and 35.9%, respectively.2. Mean frequencies of allelic combinations in Shaanxi wheats were also different. The trend of four allelic combinations in Central Shaanxi plain was the same as the whole province. The order frequencies for alleles in Northen Wei plateau was Ppo-A1a/Ppo-D1b> Ppo-A1b/Ppo-D1a>Ppo-A1a/Ppo-D1a>Ppo-A1b/Ppo-D1b. The order of frequencies for alleles in Southern Shaanixi region was Ppo-A1b/Ppo-D1b>Ppo-A1a/Ppo-D1b>Ppo-A1b /Ppo-D1a>Ppo-A1a/Ppo-D1a.3. Generally, frequency of cultivars with the lowest PPO activity in Shaanxi province was low. Therefore, an object of wheat quality improvement in Shaanxi province in the future would be to breed cultivars with lower PPO activity.4. The proportion of genotypes controlling YP content at Psy-A1 abd Psy-D1 loci was differen in Shaanxi wheat cultivars. Alleles Psy-A1a and Psy-A1b at Psy-A1 locus were found in Shaanxi wheat cultivars, respectively. The frequencies of alleles Psy-A1a and Psy-A1b were 50.5% and 49.5%, respectively, and Psy-A1c allele was absent in Shaanxi wheats. Alleles Psy-B1a, Psy-B1b and Psy-B1c at Psy-B1 locus were found in Shaanxi wheat cultivars. The frequencies of alleles Psy-B1a, Psy-B1b and Psy-B1c were 62.5%, 29.6% and 7.6%, respectively. Mean frequencies of allelic combinations in Shaanxi wheats were also different. The frequencies of allelic combinations Psy-A1b/Psy-B1b, Psy-A1a/PsyB1b, Psy-A1a/Psy- B1a, Psy-A1b/Psy-B1a Psy-A1b/Psy-B1c and Psy-A1a/Psy-B1c were 37.5%, 25%, 19.6%, 10.3%, 1.6% and 6%, respectively.5. Mean frequencies of allelic combinations in Shaanxi wheats were also different. The order of five allelic combination frequencies in Central Shaanxi plain were Psy-A1b/Psy-B1b>Psy-A1a/Psy-B1b>Psy-A1a/Psy-B1a>Psy-A1a/Psy-B1c =Psy-A1b/Psy-B1a>Psy-A1b /Psy-B1c and Psy-A1a/Psy-B1c. The order of five allelic combination frequencies in Northen Wei plateau were Psy-A1a/Psy-B1a > Psy-A1a/Psy-B1b=Psy-A1b/Psy-B1a=Psy-A1a /Psy-B1b=Psy-A1b/Psy-B1a=Psy-A1b/Psy-B1b > Psy-A1a/Psy-B1c and Psy-A1b/Psy-B1c. The five order in Southern Shaanixi region were Psy-A1b/Psy-B1b>Psy-A1a/Psy-B1b>Psy-A1b/Psy-B1a>Psy-A1a/Psy-B1a>Psy-A1a/Psy-B1c and Psy-A1b/Psy-B1c .6. Generally, the number of cultivars with the lowest PPO activity was slightly lower, and the number of cultivars with high YP content in Shaanxi was slightly higher. The differece in YP content of cultivars released in different Shaanxi regions was largely determined by their breeding target and plant requirement.In this study, using the eight function molecular markers, the genotypes controlling PPO activity and YP content in Shaanxi wheat cultivars was firstly detected. The distribution of the genotypes in different wheat region was also analyzed. According to the relationship about the genotype with PPO activity and YP content in Shaanxi wheat cultivars, the PPO activity and YP content of tetesed cultivars were avaluted.更多还原