【作者】 窦俊辉；

【导师】 喻树迅；

【作者基本信息】 中国农业科学院 ， 作物遗传育种， 2010， 硕士

【摘要】 棉花是我国的重要经济作物之一,也是关系到国计民生的重要的战略物资之一,它关系到我国数千万人的就业。但是我国人多地少,粮棉争地矛盾突出,解决这一矛盾的一个重要途径就是短季棉的推广。短季棉往往存在着早熟早衰的问题,其严重影响棉花的产量和质量。研究表明,超氧化物歧化酶(SOD)是在短季棉早熟不早衰复杂调控过程中一个很重要的酶类,是消除超氧阴离子的第一道防线。因此,在短季棉群体中对SOD进行研究具有重要意义,可以为短季棉的生化辅助育种提供理论依据。本研究以早熟早衰中棉所10×早熟不早衰的辽4086为亲本建立的F2：6/F2：7群体为试验材料,分别从分子标记,蛋白,转录和田间性状的角度去研究SOD活性与早熟早衰和早熟不早衰的关系。开发了一个SOD活性的新STS标记,鉴定了以早熟早衰的中棉所10x早熟不早衰的辽4086为亲本建立的后代群体的早衰特性,研究了不同时期SOD同工酶的变化。主要研究结果如下：1)、首先测定了本群体246个株系的SOD酶的活性,筛选出两组SOD酶活性差异较大的材料；提取了全部株系的DNA,然后用以SOD的EST序列设计的引物对两组SOD酶活性差异较大的材料的DNA进行扩增。在两组材料中,SOD酶活性大的材料扩增出587bp的片段,SOD酶活性小的扩增出842bp的片段；利用本群体对此标记验证表明,在全部的材料中,有56份扩增出587bp的片段,有190份扩增出842bp的片段,扩增出587bp片段材料的SOD酶活性的平均值约为840.476(unit/gFW)以上,但也有少量SOD活性低的材料扩增出短片段；扩增出842bp片段的SOD酶活性的平均值大约为690.276(unit/gFW),但也有少量SOD活性在840.476(unit/gFW)以上的材料扩增出长片段。说明此标记可用来判断短季棉SOD酶活性的高低。2)、依据SOD酶活性变化的总规律,在2009年7月25日(Ⅰ),2009年8月10日(Ⅱ)及2009年8月25日(Ⅲ)分别对本群体的材料进行取样。测定酶活性,提取RNA,然后进行同工酶电泳和RT-PCR。结果表明,无论是在转录水平和翻译水平,SOD的表达量都在Ⅱ时期达到最高,说明SOD酶活性的变化趋势与它的基因表达量变化趋势是一致的。其中,Cu/Zn-SOD基因在构成总SOD酶活性中起着最大作用,有报道指出Cu/Zn-SOD活性可占到SOD总活性的86%。系统进化分析结果表明,在不同的植物中,棉花与葡萄的SOD基因相似性高,相同种类的SOD基因之间相似性高；在棉花中,这种趋势更为明显,且在相同组织中的各种SOD基因较为相似。3)、对本群体田间调查的结果进行分析,结果表明：各个数量之间的交互作用关系是非常复杂的,既有相辅相成,也有互相制约,某一个性状的变化往往也会导致另外一些性状的变化。SOD与各性状(除整齐度外)都呈极显著的正相关,说明SOD对各性状所起的作用都为正效应。更多还原

【Abstract】 Cotton is one of an import ecnomomic crops in china and it is strategic goods which have close relationship with our country’s economy and people’s life. It can influence tens millions of people’s job in our country. However, our country has a large number of people while only has limited land, the contradictory between cotton and grains is very severe. An import way to solve this problem is promoting the short-seasoned cotton, but it always has the problem of early-decrepit which has negative influence on the yield and quality of cotton.SOD is an import enzyme in the complex process of short-seasoned cotton not early-decrepit and is the first line to get rid of ROS.So it is very important to carry some research on SOD, which can provide support to bio-chemical breeding.This research is based on the population which is the descendant of ZhongmiansuolO and Liao4086, to probe the relationship between earliness with decrepit and earliness but not decrepit from the perspectives of molecular marker, protein, transcription and field characteristics.Develope a new SOD marker, detect the characteristics of this population and the change of SOD enzyme of different time. The main results are:1)First determinated all of the 246 lines SOD activities and choose 2 groups:one is with high SOD activity and the other is with low SOD activity.Then uses the premiers which are desighed according to the EST of SOD to amplify their DNA. The results are:the group with high SOD activity have short fragment and the other group have long fragment. Then use all of the lines to check the reliability of this marker, we found that there are 56 lines are short fragments and 190 lines are long fragments. The average SOD activity of those lines which are 587bp is 840.476(unit/gFW)and the other is 690.276(unit/gFW). So this marker can be used to detect the SOD activity of short-seasoned cotton.2) According to the regulation of the SOD activity in short-seasoned cotton, took the samples at July 25th 2009, August 10th 2009 and August 25th 2009. Determinated their activities, extracted RNA, and then used them to carry the further analysis.The results show that no matter at translation level or trascriptive level, the expression of SOD is highest atⅡ,the same as the change of SOD activity. Cu/Zn-SOD play a dominate role in the formation of the total SOD activity. Cotton SOD gene is very similar with grapes’,and the sme type SOD is very same as each other and SODs in the same organ is very similar.3) According to the analysis of field investigation results, the relationships among all the characteristics are complicated; they promote each other and limited each other, one’s change often bring changes to others. SOD has predominated relationship with cotton field characteristics, this shows that SOD has positive influence on cotton field characteristics.更多还原