不同抗旱性小麦的萌发特性及对干旱的响应

NWIPB OpenIR

	不同抗旱性小麦的萌发特性及对干旱的响应
其他题名	Germination characteristics and responses to drought stress in wheat with different drought resistance
	赵会君
学位类型	硕士
导师	张怀刚
	2008-06-05
学位授予单位	中国科学院西北高原生物研究所
学位授予地点	西北高原生物研究所
关键词	干旱胁迫小麦萌发特性选择指标
摘要	中文摘要干旱成为限制农业生产的重要因素。遗传育种学家将培育抗旱品种，提高作物自身的抗旱性作为抗旱育种的主要目的。前人在许多方面对小麦抗旱机理进行了研究，如小麦形态方面、生理方面及生理生化方面对干旱胁迫的响应，最近几年在小麦抗旱基因的分子定位及转录因子和激素调控方面研究也取得了可喜的进展。然而，小麦抗旱性是由多基因控制的数量性状的综合体现，在各生育阶段的表现并不完全一致。本研究拟从种子萌发、植株发育、产量与品质形成进行探讨，了解有关性状对干旱的响应，筛选适宜的抗旱选择指标。本研究选用中国科学院西北高原生物研究所培育的高原号系列春小麦品种为主要研究材料，同时采用了青海省和甘肃省的农家抗旱品种和引进品种等，其中抗旱品种有高原671、高原602、高原158、高原913、定西24、和尚头和老芒麦，干旱敏感品种有高原448、波他姆、高原205、高原314和高原V028。在种子萌发试验中，以20%PEG-6000（聚乙二醇）作为干旱胁迫剂进行了干旱模拟试验，研究了种子萌发特性与α-淀粉酶活性。并在盆栽与大田控水条件下，研究了旗叶含水量、叶绿素含量、干物质积累、蛋白质组分和面粉品质等对干旱胁迫的响应。主要结果如下：（1）在萌发阶段，20%PEG-6000处理能显著的抑制各品种的胚芽鞘长度和主胚根长度及发芽率，但是抗旱品种的形态指标明显受抑制程度小于干旱敏感品种，胚芽鞘长度可以作为一个可靠的抗旱筛选指标。（2）α-淀粉酶活性作为萌发阶段的主要水解酶，在受到干旱抑制时，抗旱品种的α-淀粉酶活性明显高于干旱敏感品种，通过非变性凝胶电泳检测，抗旱品种同工酶表达受抑制程度较低，而干旱敏感品种表达受抑制明显，因此α-淀粉酶活性及同工酶可以作为萌发阶段抗旱筛选及分子标记指标。（3）在灌浆到成熟期，抗旱品种旗叶渗透调节能力明显高于干旱敏感品种，叶片持水能力强，叶绿素总含量随着灌浆的进行下降比较缓慢，保证了灌浆的顺利进行。（4）在干旱胁迫下，小麦出粉率低，籽粒蛋白含量有所提高，蛋白质组分发生变化，与对照相比醇溶蛋白含量增加，球蛋白含量有所下降，谷蛋白含量有所提高，清蛋白含量也比较稳定。粉质测试结果显示，干旱胁迫影响了面团的粉质参数，使面粉吸水率下降，面团形成时间，稳定时间及断裂时间都缩短，评价值降低，但公差指数没有明显变化规律。关键词：干旱胁迫，小麦，萌发特性，选择指标
其他摘要	Abstract Germination characteristics and responses to drought stress in wheat with different drought resistance Zhao Huijun (Botany) Directed by Prof. Zhang Huaigang Ph.D Drought stress becomes a major limiting factor to farming. The use of drought resistant cultivars is an effective way to solve the problem.The mechainism of wheat adaption to drought resistance, indexes for evaluating drought resistance and genetic analysis on some traits related to drought resistance were studied. However, traits related to drought resistance are controlled by QTL genes. Responses to drought stress do not perform uninously at different growing period. In the experiment, germination characteristations, plant development, yield and quality formation were studied to understand their responses to drought stress and choose suitable selection markers for drought resistance in wheat breeding. Twelve wheat cultivars developed by Northwest Institute of Plateau Biology, the Chinese Academy of Sciences, and from Qinghai, Gansu Provinces of China and Mexico were used. Drought resistant cultivars included Plateau 671, Plateau 602, Plateau 158, Plateau 913, Dingxi 24, Heshangtou and Laomangmai. Sensitive cultivars to drought stress were Plateau 448, Potam, Plateau 205, Plateau 314 and Plateau V028. Germination characteristics of sedds and α-amylase activities were determined under 20%PEG-6000 stress and non-stress. α-amylase activities were measured with reduced sugar assay of 3,5-dinitrosalicylic acid(DNS) and α-amylase iso-enzymes were analyzed by acrylamide gel electrophoresis. Water content and Chlorophly content in flag leaves, grain dry matter accumulation, protein compositin and rheological properties of flour were studid in the fileds outside and inside of greenhouse. The results are as follows: (1) Coleoptile length under 20%PEG could be used for selecting drought tolerance cultivars. Compared with mormal condition, coleoptiles of the drought sensitive cultivars were restrained more obviously and their coleoptile lengths were obviously shorter than drought resistant cultivars. The drought condition also restrains the length of primary radicles and the number of radicles. (2) There was significant difference in α-amylase activities among the cultivars under the two conditions. Under the drought-stressed condition, α-amylase activities of the drought-resistant cultivars were significant higher than those of the drought-sensitive cultivars. During germination under drought stress, α-amylase activities and α-amylase iso-enzymes could be used as selective indicators for drought resistance in wheat breeding. (3) Drought stress could affect the quality and productivity, biomass, grain yield and kernel number of the cultivars. However drought tolerant cultivars were affected less than the sensitive cultivars. (4) Quality of spring wheat cultivars under drought stress condition became poorer. Flour yield decreased, protein content decreased in the serious drought stress. Protein constitution also changed. Key words: drought resistance; wheat; germination characteristics; selective indicator
页数	67
语种	中文
文献类型	学位论文
条目标识符	http://210.75.249.4/handle/363003/3186
专题	中国科学院西北高原生物研究所
推荐引用方式 GB/T 7714	赵会君. 不同抗旱性小麦的萌发特性及对干旱的响应[D]. 西北高原生物研究所. 中国科学院西北高原生物研究所,2008.

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