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马铃薯属于干旱敏感型作物,当前生产上的马铃薯品种多数不耐旱,中国马铃薯抗旱育种进程又受到遗传背景狭窄的制约。引进外来种质资源,拓宽我国马铃薯遗传背景,加快选育抗旱品种是马铃薯应对干旱的关键策略。2016年和2017年,在常规滴灌和雨养条件下,利用增广设计方法,以生产上常用的5个马铃薯品种为对照,对来自国际马铃薯中心的315份高代品系和中国已有的3个品种进行抗旱性评价。通过AMMI模型和GGE模型分析基因型、环境及二者互作对产量的影响,并结合抗旱指数筛选抗旱性稳定且产量高的材料。从整体上看,在雨养条件下,两年马铃薯平均产量差异较小,但是变异系数较大,常规滴灌条件下正好相反。马铃薯产量受基因型、环境及其交互作用的显著影响,其变异平方和分别占总处理平方和的43.39%、39.36%和17.26%;C93和YS902两年的抗旱指数均高于对照品种,稳产性好,C48虽然抗旱指数相对较低,但是高产和稳产性高于所有材料。筛选出来的材料不仅可以作为抗旱育种亲本,还可以通过进一步研究其抗旱机制,为抗旱育种提供理论支持。 相似文献
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干旱,半干旱地区作物育种的困惑与出路 总被引:5,自引:2,他引:5
粮食问题主要取决于一年生谷类作物产量。作物产量低而不稳的原因主要是病虫害及各种胁迫生境,其中干旱缺水为最大的产量限制因素,提高作物生产力的途径有二:其一是改善作物的生长环境,其二是通过育种手段选育在各肿胁迫环境中具有优良表现的基因型(品种)。矮秆化育种手段使水肥充裕区小麦产量有显著的提高,是通过提高收获指数获得的。干旱、半干旱地区育种却未能获得显著效果,要提高干旱、半干旱地区小麦育种的成效,对干旱 相似文献
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为筛选苜蓿萌发期抗旱性鉴定指标以及抗旱苜蓿种质材料,为苜蓿抗旱新品种选育提供理论和基础材料。以59份抗旱性不同的国内外苜蓿种质为材料,设置加蒸馏水和加-0.6 Mpa PEG-6000水溶液2个处理,研究了与抗旱性相关的根长、芽长、发芽势、发芽率、发芽指数、活力指数和根芽比等7个指标的变化,采用相关性分析、隶属函数、综合抗旱系数、灰色关联、逐步回归和聚类分析相结合的方法,对59份苜蓿种质萌发期抗旱性进行综合评价及抗旱指标筛选。结果表明:干旱胁迫对苜蓿萌发期各指标均有显著影响。筛选出萌发期抗旱性较强的苜蓿种质材料有草原3号、赛迪7、WL903,可作为抗旱育种和抗旱机理研究材料。根长、发芽率和活力指数对干旱胁迫的反应较其他指标敏感,可作为苜蓿品种抗旱性鉴定及抗旱品种选育时优先考虑的指标。试验结果也说明采用以抗旱性度量值(D值)为主要参数,以加权抗旱系数(WDC值)作为辅助参数的综合评价方法进行苜蓿抗旱性综合评价、评价指标筛选是合理准确的。 相似文献
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高粱[Sorghum bicolor(L.)Moench]是世界上重要的粮食、饲料、纤维和能源作物之一,因其根系发达、叶片蜡质层厚密、渗透调节能力强、光合效率高等特点,在干旱条件下具有很强的适应性。因此,高粱在气候变化、水资源短缺和满足世界粮食需求等方面发挥着重要的作用。干旱是制约世界农业生产的主要逆境因素之一,如何解决高粱在干旱条件下的产量问题仍然是育种工作者面临的巨大挑战。为了给高粱抗旱育种提供参考,本文综述了高粱抗旱性的鉴定方法、鉴定指标和优异抗旱种质资源,以及高粱花前抗旱和花后抗旱相关性状QTL定位的研究进展,并对高粱抗旱性研究的发展趋势提出了展望。认为应建立规模化高粱种质资源抗旱鉴定体系、选择合适的全生育期自然鉴定地点,筛选抗旱种质资源;利用高通量测序技术,高效挖掘高粱抗旱性基因;建立高粱遗传转化体系、运用基因编辑等生物技术,加快高粱抗旱育种进程。 相似文献
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蚕豆杂种F_2主要数量性状遗传力和遗传进度的初步研究 总被引:4,自引:0,他引:4
研究作物数量性状的遗传力和遗传进度可以提高育种效率。因为这些遗传参数能够为育种提供较准确的信息,使系统选育和杂交育种工作能较好地选配亲本和确定杂种的选择世代及进度。我国学者对这些遗传参数的研究,在水稻、小麦、油菜等作物方面报道较多,而在蚕豆上报道较少。黄文涛等曾对18个蚕豆生产品种性状间的相关性及其通径系数进行过研究。徐洪琦等曾研究过5个高产蚕豆品种产量因素遗传变异情况。 相似文献
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一个值得深入研究的小麦种质资源—农林10号 总被引:1,自引:0,他引:1
改良日本小麦品种农林10号的衍生品种小罂粟(农林89号)获得成功,抗旱高产育种取得重大突破。鲁麦13号率先在非灌溉条件下创造了9244.5 kg/hm2的高产纪录;鲁麦14号则成为20世纪90年代初期黄淮冬麦区栽培面积最大的品种。该品种不仅高产、多抗、广适,而且还是很好的农艺亲本被育种家广泛利用,已选育出49个新品种,成为黄淮冬麦区新一轮主栽品种,创造了巨大的经济效益和社会效益。充分显示出种质资源的创新在育种和保障国家粮食安全中的地位与作用。本文还就品种资源的研究和利用进行了讨论。 相似文献
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On the origin of the Hirudinea and the demise of the Oligochaeta 总被引:10,自引:0,他引:10
Martin P 《Proceedings. Biological sciences / The Royal Society》2001,268(1471):1089-1098
The phylogenetic relationships of the Clitellata were investigated with a data set of published and new complete 18S rRNA gene sequences of 51 species representing 41 families. Sequences were aligned on the basis of a secondary structure model and analysed with maximum parsimony and maximum likelihood. In contrast to the latter method, parsimony did not recover the monophyly of Clitellata. However, a close scrutiny of the data suggested a spurious attraction between some polychaetes and clitellates. As a rule, molecular trees are closely aligned with morphology-based phylogenies. Acanthobdellida and Euhirudinea were reconciled in their traditional Hirudinea clade and were included in the Oligochaeta with the Branchiobdellida via the Lumbriculidae as a possible link between the two assemblages. While the 18S gene yielded a meaningful historical signal for determining relationships within clitellates, the exact position of Hirudinea and Branchiobdellida within oligochaetes remained unresolved. The lack of phylogenetic signal is interpreted as evidence for a rapid radiation of these taxa. The placement of Clitellata within the Polychaeta remained unresolved. The biological reality of polytomies within annelids is suggested and supports the hypothesis of an extremely ancient radiation of polychaetes and emergence of clitellates. 相似文献
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Göran Malmberg 《Systematic parasitology》1990,17(1):1-65
Data on the ontogeny of the posterior haptor of monogeneans were obtained from more than 150 publications and summarised. These data were plotted into diagrams showing evolutionary capacity levels based on the theory of a progressive evolution of marginal hooks, anchors and other attachment components of the posterior haptor in the Monogenea (Malmberg, 1986). 5 + 5 unhinged marginal hooks are assumed to be the most primitive monogenean haptoral condition. Thus the diagrams were founded on a 5 + 5 unhinged marginal hook evolutionary capacity level, and the evolutionary capacity levels of anchors and other haptoral attachement components were arranged according to haptoral ontogenetical sequences. In the final plotting diagram data on hosts, type of spermatozoa, oncomiracidial ciliation, sensilla pattern and protonephridial systems were also included. In this way a number of correlations were revealed. Thus, for example, the number of 5 + 5 marginal hooks correlates with the most primitive monogenean type of spermatozoon and with few sensillae, many ciliated cells and a simple protonephridial system in the oncomiracidium. On the basis of the reviewed data it is concluded that the ancient monogeneans with 5 + 5 unhinged marginal hooks were divided into two main lines, one retaining unhinged marginal hooks and the other evolving hinged marginal hooks. Both main lines have recent representatives at different marginal hook evolutionary capacity levels, i.e. monogeneans retaining a haptor with only marginal hooks. For the main line with hinged marginal hooks the name Articulon-choinea n. subclass is proposed. Members with 8 + 8 hinged marginal hooks only are here called Proanchorea n. superord. Monogeneans with unhinged marginal hooks only are here called Ananchorea n. superord. and three new families are erected for its recent members: Anonchohapteridae n. fam., Acolpentronidae n. fam. and Anacanthoridae n. fam. (with 7 + 7, 8 + 8 and 9 + 9 unhinged marginal hooks, respectively). Except for the families of Articulonchoinea (e.g. Acanthocotylidae, Gyrodactylidae, Tetraonchoididae) Bychowsky's (1957) division of the Monogenea into the Oligonchoinea and Polyonchoinea fits the proposed scheme, i.e. monogeneans with unhinged marginal hooks form one old group, the Oligonchoinea, which have 5 + 5 unhinged marginal hooks, and the other group form the Polyonchoinea, which (with the exception of the Hexabothriidae) has a greater number (7 + 7, 8 + 8 or 9 + 9) of unhinged marginal hooks. It is proposed that both these names, Oligonchoinea (sensu mihi) and Polyonchoinea (sensu mihi), will be retained on one side and Articulonchoinea placed on the other side, which reflects the early monogenean evolution. Except for the members of Ananchorea [Polyonchoinea], all members of the Oligonchoinea and Polyonchoinea have anchors, which imply that they are further evolved, i.e. have passed the 5 + 5 marginal hook evolutionary capacity level (Malmberg, 1986). There are two main types of anchors in the Monogenea: haptoral anchors, with anlages appearing in the haptor, and peduncular anchors, with anlages in the peduncle. There are two types of haptoral anchors: peripheral haptoral anchors, ontogenetically the oldest, and central haptoral anchors. Peduncular anchors, in turn, are ontogenetically younger than peripheral haptoral anchors. There may be two pairs of peduncular anchors: medial peduncular anchors, ontogentically the oldest, and lateral peduncular anchors. Only peduncular (not haptoral) anchors have anchor bars. Monogeneans with haptoral anchors are here called Mediohaptanchorea n. superord. and Laterohaptanchorea n. superord. or haptanchoreans. All oligonchoineans and the oldest polyonchoineans are haptanchoreans. Certain members of Calceostomatidae [Polyonchoinea] are the only monogeneans with both (peripheral) haptoral and peduncular anchors (one pair). These monogeneans are here called Mixanchorea n. superord. Polyonchoineans with peduncular anchors and unhinged marginal hooks are here called the Pedunculanchorea n. superord. The most primitive pedunculanchoreans have only one pair of peduncular anchors with an anchor bar, while the most advanced have both medial and lateral peduncular anchors; each pair having an anchor bar. Certain families of the Articulonchoinea, the Anchorea n. superord., also have peduncular anchors (parallel evolution): only one family, the Sundanonchidae n. fam., has both medial and lateral peduncular anchors, each anchor pair with an anchor bar. Evolutionary lines from different monogenean evolutionary capacity levels are discussed and a new system of classification for the Monogenea is proposed.In agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. EditorIn agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. Editor 相似文献
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