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《华北农学报》2015,(4)
为掌握中国油菜品种的黑胫病抗性水平,为抗病育种及品种合理布局提供理论依据。在室内采用子叶穿刺接种法,对35个油菜品种开展了黑胫病的抗性评价及抗病基因推导研究。供试品种中没有发现对病原菌Leptosphaeria maculans和Leptosphaeria biglobosa表现高抗或免疫的品种,只有3个品种可以兼抗Leptosphaeria maculans和Leptosphaeria biglobosa,但均表现低抗。供试的35个品种对12个菌株共产生了17种反应型,其中12个品种的反应型与鉴别寄主的完全相同,18个品种的反应型与鉴别寄主的非常相近,5个品种的反应型不同于任何鉴别寄主。抗病基因推导,已知的12个黑胫病抗性基因Rlm1~9,Lep R1~3多数以基因组合的形式分布在我国的30个品种中,这些主栽品种可能含有已知的或新的抗病基因。说明现有的油菜种质资源中可能蕴藏着对改良黑胫病抗性具有潜在应用价值的基因资源。 相似文献
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近年来随着对植物抗病机理及信号转导途径的深入研究和探索,以及通过分子生物学手段新的抗病基因和病原菌无毒基因不断被克隆,科研人员对于植物三型信号分泌系统中抗病（R）基因和无毒(Avr)基因的结构、功能,作用模式及作用机制具有更加深入的认识。深入研究病原菌—寄主之间的相互作用关系,为制定更为有效的植物病害防治措施提供了依据。该文通过对三型信号分泌系统中植物病原识别受体的组成部分,抗病基因的结构域及种类,抗病基因与无毒基因及相互作用的两种模式及具体机制的总结,从植物抗病基因角度探讨了三型信号分泌系统下植物的抗病机制并在此基础上进行了前景展望。 相似文献
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水稻稻瘟病抗性基因的定位、克隆及育种应用研究进展 总被引：3，自引：2，他引：1
稻瘟病是一种世界性的水稻病害,抗病品种的培育和种植是控制该病害最为经济有效的方法,而抗病基因的发掘与利用则是抗病育种的基础和核心。本研究就稻瘟病抗病基因的遗传、定位、克隆及育种应用情况进行了概述,介绍了稻瘟病广谱抗原和抗病基因、隐性抗病基因研究的最新进展,指出近一半的抗病基因是通过F2分离群体鉴定的,目前已定位的稻瘟病主效抗病基因超过86个,微效基因约350个,应用图位克隆等方法,20个稻瘟病主效抗病基因和2个微效基因已从不同的水稻品种中被克隆。这些基因的定位和克隆是有效开展稻瘟病抗性分子育种的基础。最后,结合笔者从事水稻稻瘟病抗性遗传的工作实践对稻瘟病抗病基因研究存在的问题进行了分析和展望,相信随着越来越多各类型抗性基因的生产应用,稻瘟病对水稻的危害最终能得到有效的控制。 相似文献
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抗病基因的分离和克隆对于实施作物抗病基因育种及开展抗病机制的研究具有重要意义。目前植物抗病基因的克隆方法主要有转座子标签技术和图位克隆技术。该法对于未知基因产物或者没有进行精细定位的性状来讲，其应用受到极大限制。近年来，很多研究探索了利用同源序列发掘抗病候选基因的途径。本研究归纳和总结了三条发掘抗病候选基因的方法，旨在对作物抗病基因及其连锁标记的发掘起到一定的指导作用。 相似文献
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《分子植物育种》2017,(4)
NBS类抗病基因是植物中最大的一类抗病基因。亚麻荠是一种新型能源及特用油料作物,抗病、虫、杂草及逆境能力极强。然而,有关其抗性分子机理鲜有报道。本研究采用NB-ARC标准结构域的HMM模型,对亚麻荠本地蛋白质数据库进行检索分析,在全基因组水平上鉴定NBS类抗病基因。结果表明亚麻荠基因组共有472个NBS类抗病基因,分布于17条染色体上,56%的基因成簇分布。所有串联重复基因也都以基因簇的形式出现,这表明串联重复有利于基因簇的形成。系统发生树分析显示TIR-NBS-LRR(TNL)和CC-NBS-LRR(CNL)两类亚家族的抗病基因可能在进化过程中遵循不同的进化路径,导致其在应对病原菌侵染时发挥不同的功能。本研究发现将为鉴定新的植物抗病基因和解析亚麻荠高抗病机制提供科学参考。 相似文献
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甘肃省主要小麦生产品种(系)及抗源材料抗白粉病基因推导分析 总被引：4，自引：0，他引：4
选用17个致病力不同的小麦白粉病菌菌系,对64个甘肃省主要生产品种(系)及抗源材料进行了苗期白粉病抗性鉴定,并结合系谱分析推导这些品种(系)所含抗病基因。初步判断陇原932含有Pm5及未知抗病基因;西峰20含有Pm6及未知抗病基因;98保1-2含有Pm8及未知抗病基因;863-13和石7816含有Pm19;天选43等6个品种(系)含有Pm21;兰天13等18个品种(系)对所有供试菌系均表现感病,与其他35个供试品种(系)一致,可能含有未知抗病基因或基因组合。聚类分析支持基因推导结果。 相似文献
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<正>病害是影响作物高产稳产的重要因素之一。植物抗病基因(R基因)在长期的进化过程中表现出复杂的进化模式。很多研究表明,植物R基因是以基因家族的形式存在,通常成簇排列从而形成复杂结构。经由旁系同源抗病基因间频繁的序列重组和交换的一类抗性基因叫I型R基因,而较少或没 相似文献
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《Soil Technology》1990,3(3):225-229
Compaction of soils under agricultural use is widespread. Its effects on crops and soil properties are complex. The author's experience has suggested that cultivation to break up compaction of rutted surfaces immediately after the harvest of many crops, particularly of potatoes and root crops, can reduce the risk of further serious compaction. Deep cultivation (subsoiling) can have adverse effects and its use should be confined of land where examination of the soil has shown that a layer of compact soil is present, and that the soil is dry enough for fracturing to take place. 相似文献
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转基因作物对环境影响的讨论 总被引：6，自引：0，他引：6
随着转基因作物的不断推广，转基因作物对环境的影响受到越来越多的关注，其中包括转基因作物潜在的侵袭力，基因漂移，对生物多样性的冲击，对农业生产的影响等等。这些议题具有跨学科性和高度的复杂性，要正确评价它们，就必须设定一个合适的标准作为参照。通过传统育种方法培育的新品种对环境的影响成为最合适的参照，这些新品种被广为认可，是现代农业重要的组成部分。在许多实例当中。转基因作物对环境的影响与通过传统育种方式所得到的新品种对环境的影响非常相似。通过比较对转基因作物进行恰当评价，会使植物转基因技术更好的发挥作用。 相似文献
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转BADH基因苜蓿T-DNA侧翼序列分析及转化事件特异性分析 总被引：2，自引：1，他引：1
为了从分子水平上鉴别不同的转基因株系,以转BADH基因苜蓿的T0代基因组DNA为模版,采用热不对称交错PCR(TAIL-PCR)方法分离其外源基因插入位点的侧翼序列,获得了B127株系的左翼序列和右翼序列,以及B125、B138、B295和B196株系的左翼序列。侧翼序列特征分析表明,有的T-DNA边界序列被删除,有的边界序列被保留,并填充了一段未知来源的核苷酸序列。根据侧翼序列中插入载体序列和紧邻插入序列的基因组序列特征,分别设计PCR扩增的上、下游引物,并对获得的42个转BADH株系分别进行左、右翼序列的扩增,结果表明,转基因植株B106、B125、B138、B157、B158、B289、B295、B305和B127具有相同的扩增条带,B203、B220、B223和B196具有相同的扩增条带,说明这些株系可能仅来源于2个转化事件。本研究建立的事件特异性检测方法可以准确地将不同的转化株系区别开来。 相似文献
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Sustainable N management of intensive vegetable crops requires accurate and timely on-farm assessment of crop N status. Proximal fluorescence-based sensors are promising tools for monitoring crop N status, by providing non-destructive optical measurements of N-sensitive indicator compounds such as chlorophyll and flavonols. The ability of the Multiplex® fluorescence sensor to determine crop N status was evaluated in two indeterminate cucumber crops grown in contrasting seasons (autumn and spring). Three fluorescence indices, leaf chlorophyll (SFR) and flavonols (FLAV) contents, and their ratio (Nitrogen Balance Index, NBI) were evaluated, and their consistency between the two crops compared. Actual crop N status was assessed by the Nitrogen Nutrition Index (NNI), calculated as the ratio between the actual and the critical crop N contents (i.e., the minimum N content for maximum growth). There were strong relationships between each of SFR, FLAV and NBI with crop NNI, for most weekly measurements made throughout the two crops. For the three indices, coefficients of determination (R2) were mostly 0.65–0.91 in the autumn crop, and 0.71–0.99 in the spring crop. SFR values were generally comparable between the two crops, which enabled the derivation of common relationships with NNI for individual phenological phases that applied to both cropping seasons. FLAV and NBI values were not comparable between the two crops; FLAV values were appreciably higher throughout the spring crop, which was attributed to the higher solar radiation. Consequently, phenological relationships of FLAV and NBI with NNI were established for each individual cropping season. Our findings suggested that SFR was the most consistent index between cropping seasons, and that NBI was the most sensitive index within each season. Regardless of the index and crops, all fluorescence indices were weakly related to crop NNI during the short vegetative phase while stronger relationships were found in the reproductive and harvest phases. This study also showed that the three fluorescence indices were sensitive to and able to distinguish deficient from optimal crop N status, but that they were insensitive to discriminate optimal from slightly excessive N status. Overall, this study demonstrated that fluorescence indices of chlorophyll content (SFR), flavonols content (FLAV) and nitrogen sufficiency (NBI) can be used as reliable indicators of crop N status in cucumber crops; however, there was variability in FLAV and NBI values between cropping seasons and a lack of sensitivity in the range of optimal to slightly excessive crop N status. 相似文献
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Large nitrogen (N) fertilizer applications are a feature of intensive vegetable production systems, and optimal N management is required to maximize N use efficiency and minimize N losses. Vegetation indices (VIs) of canopy reflectance, measured with proximal sensors, are generally strongly related to crop N status. For practical application, sufficiency values that distinguish between N deficiency and sufficiency are required. In this work, sufficiency values of VIs for maximum crop growth and for yield were determined for two cucumber crops grown in contrasting seasons (Autumn and Spring). Canopy reflectance was measured with a Crop Circle ACS-470 sensor. Sufficiency values for maximum growth were based on the relationships of VIs with the Nitrogen Nutrition Index (NNI), i.e. the ratio between actual and critical crop N contents. Sufficiency values for maximum yield were based on linear-plateau relationships of yield with VIs. Strong relationships were obtained between all VIs and both NNI and yield for most of the weekly measurements during both crops. For NNI, best-fit relationships were linear, quadratic, power or exponential, and had coefficients of determination (R2) of 0.61–0.98. For yield, most linear-plateau relationships between yield and VIs had R2 values of 0.47–0.89. VIs based on reflectance in green and red edge had slightly better relationships with NNI and yield than VIs in the red, with the Green Normalized Difference Vegetation Index (GNDVI) and the Green Ratio Vegetation Index (GRVI) being the most sensitive and consistent indices for estimating both crop NNI and yield. Relationships between VIs and NNI and yield for all weekly measurements of each crop, and for the two crops combined, were also analyzed to provide unique sufficiency values for maximum growth and yield that applied to the entire crop cycle of each crop and of both crops considered together. Overall, there were slight differences between sufficiency values for maximum growth and for maximum yield and the unique sufficiency values were generally intermediate to the weekly sufficiency values. This study demonstrated the potential for using VIs for monitoring crop N nutrition and yield in cucumber. The calculated sufficiency values of VIs may facilitate the use of proximal optical sensors in farming practice for optimal N management through periodic monitoring for deviation from sufficiency values. 相似文献
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农作物受害虫侵害严重,给农业生产带来巨大损失,喷施化学杀虫剂使害虫产生抗药性,且污染环境。近年来,转基因技术研究不断深入,抗虫转化研究工作进展迅速。鉴定转基因植物的方法技术有很多种,在此主要阐述了利用标记基因进行鉴定,分子标记,免役技术三大类方法,并对其原理分别进行了简单介绍。 相似文献
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抗虫转基因植物鉴定方法的研究进展 总被引：1，自引：0，他引：1
农作物受害虫侵害严重,给农业生产带来巨大损失,喷施化学杀虫剂使害虫产生抗药性,且污染环境。近年来,转基因技术研究不断深入,抗虫转化研究工作进展迅速。鉴定转基因植物的方法技术有很多种,在此主要阐述了利用标记基因进行鉴定,分子标记,免役技术三大类方法,并对其原理分别进行了简单介绍。 相似文献
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中国作物新基因发掘：现状、挑战与展望 总被引：6，自引：0，他引：6
中国作物新基因发掘是实现中国作物种质资源优势向基因资源优势转变和作物分子育种的基础。本文对中国近10年来水稻、小麦、玉米、大豆、棉花和油菜等主要作物基因发掘研究的进展进行了分析和评述。中国作物基因发掘也取得了一系列突破性进展：(1)创制出一批具有特色的基因发掘材料,包括基于中国作物遗传多样性的核心种质、基于优异资源的遗传分离群体和基于人工诱变的突变体等;(2)基因发掘技术和方法有所突破,尤其是在针对基因特点整合各种基因发掘技术、改进基因/QTL的生物统计算法等,提高了基因发掘的效率;(3)作物农艺性状的标记与基因定位已成为常规遗传研究方法,初步定位了一批抗病、抗逆、优质、养分高效、高产相关基因/QTL,其中,有500多个基因已精细定位;(4)以水稻为代表的作物基因克隆及功能研究在国际上受到瞩目,在主要作物中已克隆了300多个基因,其中,在目标作物中验证的基因数超过70个。在国际作物基因发掘高效化、规模化及实用化发展过程中,中国作物基因发掘也取得了重要进展。然而,中国作物基因发掘的数量和质量还远远不能满足作物分子育种的需求,与国际作物基因发掘也存在差距,具体表现为不同作物基因发掘研究进展不平衡、发掘基因的数量还相对有限、已发掘的基因中具有重大利用价值的基因不多。针对中国基因发掘面临的问题和世界各国以及跨国生物技术公司争夺基因的巨大挑战,作者提出了中国作物基因发掘应重点提高基因发掘效率,加强重要基因克隆及基因的价值评估,以生物产业发展需求为导向的基因发掘策略。 相似文献