【作者】 蒋秀华；

【导师】 傅体华；

【作者基本信息】 四川农业大学 ， 遗传学， 2010， 硕士

【摘要】 小麦旗叶的光合作用对籽粒形成和产量贡献巨大。已有研究表明,旗叶直立的性状态与光合作用存在较大的联系。本研究采用旗叶直立(2-26)和倒披(H420)两种性状的小麦品系杂交,形成的F2：3群体为材料,对其进行光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)、蒸腾速率(Tr)测定及产量考察。通过旗叶性状对光合特性及产量的影响进行分析,结果表明,不同性状的旗叶对小麦光合指标的影响不同。直立性状的小麦旗叶净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)平均值均比性状倒披的小麦旗叶低,蒸腾速率(Tr)平均值直立的旗叶比倒披的旗叶高。不同性状的旗叶各个光合指标间差异不显著(P>0.05)。在构成小麦产量的3个因素中,旗叶性状倒披的小麦穗数和千粒重均高于旗叶直立的小麦,只是穗粒数直立的旗叶高于倒披的旗叶。不同性状的旗叶之间,穗粒数、千粒重之间的差异达到显著水平(P<0.05),穗数差异不显著(P>0.05)。表明最终形成产量过程中,除旗叶性状外,还与其他因素有关。如,源库流理论、旗叶的长、宽、叶面积、小麦群体冠层上三叶性状及它们的光合能力等。因此,关于小麦旗叶的性状对小麦产量的影响还需要进一步试验研究。同时,本文以H420(旗叶倒披)、2-26(旗叶直立)及H420x2-26的F2代224个单株为材料,对控制旗叶直立和倒披的性状进行了遗传分析,并利用AFLP技术对小麦旗叶直立形态基因进行分子标记。结果表明,在这两个亲本之间,控制旗叶直立与倒披的性状是受一对差异基因控制的,直立性状为显性。随机选取的304个AFLP引物组合,经过初筛选得到96个引物组合在2-26、H420和(-)池、(+)池间产生多态性,多态性检出率为32%。我们将两个亲本及建立的两个池与随机选取F2代两个相对性状各5株单株一起上小群体,再次筛选引物,获得了8个引物组合在他们之间稳定表现多态性。用H420x2-26的F2代224个单株对以上8个引物组合进行连锁性鉴定,发现有1个引物组合PsrI-TAG/MseI-CGA产生的220bp特异片段与旗叶直立基因具有较强连锁性。利用Mapmarker3.0软件进行连锁分析PstI-TAG/MseI-CGA产生的特异片段距目的基因的遗传连锁距离为8.1cM。为采用分子标记辅助选育高光效和高产量小麦品种以及转基因育种奠定了良好的基础。更多还原

【Abstract】 The wheat flag leaf is the most important photosynthetic organs for wheat grain production.It has been known that the ablity of photosynthesis is related to vertical shape of flag leaf. In present study, using wheat lines 2-26 and H420 with vertical shape and inverted shape of flag leaf, respectively, and their hybrid progenies as materials, net conduct photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci) and transpiration rate (Tr) were tested, and the main yield charaters were also counted. The effects on photosynthetic characteristics and yield with different shapes of the flag leaf were analyzed. The result showed that different shapes of wheat flag leaf have different influence on photosynthetic characteristics. Net photosynthetic rate (Pn), stomatal conductance (Gs), and intercellular CO2 concentration (Ci) of the vertical shape of flag leaf on average was lower than that of inverted shape of wheat flag leaf, Transpiration rate (Tr) of the vertical shape of flag leaf on average was higher than the inverted shape of wheat flag leaf. No significant differences in all Photosynthetic characteristics were founded in two different shapes of flag leaves (P> 0.05). In the three factors of forming wheat production, the wheat spike number and 1000-kernel weight of inverted shape of flag leaf were higher than that vertical flag leaves of wheat, grains per spike of vertical flag leaf was higher than the inverted flag leaves of wheat. Significant differences for grains per spike and 1000-kernel weight, and not significant difference for sipke number between two flag leaves of different shapes were observed. It showed that other factors except the shape of flag leaf had relations during the forming of wheat yield for example, For example, theory of the Origin and flow Library, length of flag leaf, width, leaf area, characters of wheat group clover canopy and their photosynthetic capacity and so on. Therefore, the shape of the flag leaf of wheat affecting on wheat yield need further study.The gene with vertical shape of wheat flag leaf was primary also maked adopted wheat line H420 with inverted flag leaf and 2-26 with vertical flag leaf and the F2 generation including 224 plants between H420×2-26 as materials by the AFLP technology. The results showed that there was one pair gene to control the vertical and inverted shape of flag leaf in the two different parents. The vertical shape of flag leaf was dominant.96 primer combinations in the 2-26, H420 and inverted flag leaf gene (+) pool and vertical flag leaf gene pools (-) were polymorphic among 304 AFLP primer combinations of randomly selected, the polymorphism rate was 32%. We used again the parents and gene pools and randomly selected five different plants from F2 generation to selected 96 primer combinations with polymorphism, eight primer combinations showing stability polymorphism among them. However,224 plants from F2 generation of H420×2-26 was used to further select for 8 primer combinations, only one primer combination, Pstl-TAG/Msel-CGA produced 220bp specific fragment to link the gene of the flag leaf was obtained. Linkage analysis by using Mapmarker3.0 software, the genetic linkage distance of specific fragment produced by Pstl-TAGIMsel-CGA to gene was 8.1 cM. It provided a good foundation for utilizing molecular marker to select high yield wheat and transgenic varieties in breeding programs.更多还原