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杂交水稻恢复系和杂交组合的耐热性评价 总被引：1，自引：0，他引：1
为减缓高温热害对水稻生产的影响,从品种出发探讨高温抗性,是水稻科研的优先领域和重大问题。本文参考农业部发布的高温行业标准评价指标,在水稻开花期,于人工气候室高温和常温处理条件下,对本课题组新育成的恢复系及生产上常用恢复系成恢727的配组品种(组合)等进行了耐高温特性鉴定,并将恢复系和品种(组合)耐热性分为5个等级。筛选鉴定出1个极耐热恢复系R4093、9个耐热恢复系(其中包括丰产性较好的恢复系,如R1015、R107等)、4个极耐热品种(组合)和25个耐热品种(组合),以及5个极不耐热恢复系、12个不耐热品种(组合)和6个极不耐热品种(组合)等。其中,耐高温对照N22、恢复系R103、R132、R642、杂交水稻品种(组合)‘川优5727’、‘宜香2115’、‘繁源A×R642’、‘中64香A×黄占’、‘川农优华占’、‘蓉18A×R1015’、‘渝香6203’和‘川优5727’在本试验中的常温结实率和相对结实率均高于70%,虽然被鉴定为中间型材料,但具有较大的耐高温潜力。试验还讨论了水稻品种的生产布局。结果表明:第Ⅰ级和第Ⅱ级品种耐高温性较好,可布局在高温易发区、高温轻发区和无高温区;第Ⅲ类品种为中间型,可布局在高温轻发区和无高温区;第Ⅳ类和第Ⅴ类品种为不耐热型和极不耐热型,可布局在无高温区,以避免高温对水稻的伤害。研究还发现父(母)本耐高温性好,不一定品种(组合)耐高温性都好,而父(母)本耐高温性不好,其品种(组合)耐高温性也不一定不好,这与父(母)本的耐高温性及配合力有关。耐热配合力好的父(母)本配出的组合多为耐热型组合,耐热配合力差的父(母)本配出的组合多为不耐热型组合。其中,恢复系R105、R642、R104和R727耐高温配合力较好,但恢复系R107、R1015耐高温配合力相对较差。不育系赣73A和内香6A的耐高温配合力较好,而繁源A、606A、608A和中64香A的耐高温配合力较差。优质稻中‘金10’耐高温配合力较好。为了更好更多地育成耐热性强的杂交稻组合,筛选耐热配合力高的亲本是关键。 相似文献
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张先程 《广西农业生物科学》1982,(1)
在“三系”配套之前,作者根据水稻的进化史,对野败不育材料所测品种的恢、保情况作了分析,认识到亲缘关系、生态差异和雄性不育的恢与保,存在着对立统一的辩证关系,从不育系的产生联想到恢复系的选育。后来从不同质源三系配套的明显差异,认为恢与保是相对的,恢复品种不局限于某一地区,其恢复基因也并不固定于某些品种中。实验证明,凡选用亲缘关系远、生态差异大的品种杂交,就容易找到保持系;反之,则容易测出恢复系。作者在1973年元月拟定的三系选育研究计划书中,曾提出要利用湖南的野败不育材料,与我国华南、台湾及东南亚热带地区的品种进行广泛测交筛选恢复系的方案,当年7月就发现了 IR24强恢复系,在我国首先实现籼型杂交水稻的“三系”配套,并较早地选出了威优、常优、南优、汕优、矮优一、二、三号等18个强优势组合。同时,提出了雄性不育遗传机理的初见,即“远缘(包括远距离)杂交、雄性不育的遗传,是决定于细胞质和细胞核的相互作用。如野生稻与栽培稻杂交,由于亲缘关系远,生态型差异大,质核不协调,其遗传信息就不能正常传递,从而破坏了花粉的正常发育,因此导致雄性不育;反之,育性则可恢复”。为了进一步证实,今后拟应用细胞遗传学、数量遗传学,生物化学、分子遗传学等方法,探索质核差异和互作的实质,以进一步了解雄性不育、杂种优势机理。 相似文献
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Susana R. Milla-Lewis Jennifer A. Kimball M. Carolina Zuleta Karen R. Harris-Shultz Brian M. Schwartz Wayne W. Hanna 《Genetic Resources and Crop Evolution》2012,59(7):1517-1526
Centipedegrass (Eremochloa ophiuroides (Munro) Hack.) has great potential as a low-input turf within the U.S. because of its lower management requirements and its tolerance to an array of environmental stresses. Only a handful of centipedegrass cultivars have been released to date, however. This is mainly due to limited morphological variation present in U.S. centipedegrass germplasm. With the objective of broadening the genetic base of this species, a germplasm collection trip was conducted in seven Chinese provinces in 1999. Although the resulting accessions exhibited morphological variation for a number of traits, little is known about levels of molecular variability in these accessions or how those levels compare to diversity in materials previously present in the U.S. Sequence-related amplified polymorphism (SRAP) markers were used in the current study to investigate these issues. Eleven primer combinations yielded 279 scored fragments. Genetic diversity, in terms of number of alleles and Dice similarity values, was highest in the Henan and U.S. groups. AMOVA indicated that while both the among and within components of variance were significant (P < 0.0001), most of the variation (94%) could be explained by differences within groups. The PCO plot showed large differences in levels of diversity in all groups evaluated. Overall, our results indicate that while the U.S. collection had high levels of diversity compared to other groups, there are alleles in the Chinese groups not represented in the U.S. collection. These materials could represent additional sources of variation to be used in centipedegrass cultivar development programs. 相似文献
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Z. S. Artemyeva I. I. Vasenev T. M. Sileva 《Moscow University Soil Science Bulletin》2009,64(4):159-163
A systematization of organo-clay combinations in zonal soils of the center of the Russian Plain is suggested. This systematization
adequately reflects the zonal features of pedogenesis and agrees with traditional estimates of the ecological state of the
soils and their tolerance toward the agrogenic degradation. The four types of organo-clay combinations are characterized by
different degrees of humification, aggregation, tolerance toward soil compaction, and tolerance toward soil degradation. 相似文献
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H. Budak P. S. Baenziger R. A. Graybosch B. S. Beecher K. M. Eskridge M. J. Shipman 《Cereal Chemistry》2003,80(5):518-523
Wheat (Triticum aestivum L.) genotypes with short mixing times usually have low mixing tolerance values, which make them more sensitive to overmixing in commercial bread production. In this study, we evaluated the genotypic and environmental effects on agronomic performance and end‐use quality of 27 experimental genotypes (hereafter referred to as mixing tolerant genotypes) which were identified in an initial screen as having short mixing times and good mixing tolerances to 1) determine whether genotypes identified in a preliminary end‐use quality screen as lines with usually long tolerances but short mixing times were due to their genotype (G), the environment (E), or G × E; and as these results were unusual, 2) determine whether or not our initial screen predicts end‐use quality, and 3) determine the stability of both agronomic and end‐use quality traits. The 27 genotypes and five check cultivars were grown in a randomized complete block design with two replicates in nine environments in 1997 and 1998. All plots were harvested for grain yield. The harvested grain from the first replicate and random genotypes from the second replicate were micromilled to produce flour samples for evaluation of flour yield, protein content, and mixograph mixing time and mixing tolerance values. Seed diameter, thousand kernel weight, and kernel hardness were also measured in three environments. Environment, G, and G × E interaction effects (mainly changes in magnitude) were significant for most agronomic and end‐use quality parameters. Our initial screen, which had identified 27 genotypes, was partially effective in identifying genotypes that have shorter mixing time values compared with their mixing tolerance values. We identified four genotypes (15%) from the mixing tolerant genotypes that had a good mixing tolerance value and relatively shorter mixing time, as did the released cultivars ‘Agate’ and ‘Scout 66’. However, mixing characteristics values of all genotypes fell within the acceptable limits, indicating our screen effectively identified genotypes with acceptable quality. Mixing tolerant genotypes, which had been identified as having short mixing time scores and long mixing tolerance scores, were considered stable across environments. 相似文献
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Opaque endosperm is the main phenotypic indicator for waxy rice, but other phenotypic and genotypic variation among waxy rice
accessions has largely been ignored. Previous studies showed that wide diversity in starch physiochemical properties exists
in both indica and japonica waxy rices, especially for starch gelatinization temperature (GT) which could be divided into a high- and a low-GT group.
In the present study, amplified fragment length polymorphism (AFLP) and inter-simple sequence repeat (ISSR) molecular markers
were employed to examine genetic diversity and relationships of 56 waxy rice accessions. A total of 358 AFLP fragments were
amplified with five primer combinations, showing a high level of polymorphism (78.3%). A total of 190 ISSR bands were generated
with a single primer and a primer pair, showing a very high level of polymorphism (92.2%). The genetic distance matrices obtained
from the two sets of markers were significantly correlated (r = 0.731, P = 0.004). The dendrogram generated with combined AFLP and ISSR markers could clearly differentiate the indica and japonica groups. Newly released varieties and breeding lines within each subspecies tended to be clustered together, whereas landraces
were more distantly placed in the dendrogram. Only one AFLP band was found specific to the indica type, while no specific bands were found for starch GT. The implications for the conservation and breeding of waxy rice are
discussed. 相似文献
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甘蔗重要种质的TRAP标记遗传多样性分析 总被引：3，自引：0，他引：3
分子标记辅助育种是提高育种效率的重要措施,但其在育种实践上的应用,依赖于甘蔗分子遗传多样性尤其是基于靶标基因标记的遗传多样性的研究以及与目标基因连锁标记的开发。糖分是甘蔗育种最重要的性状,蔗糖代谢基因与该性状的表现型密切相关。同时,甘蔗栽培上不时也遭受寒害胁迫。为此,本试验率先在国内应用TRAP标记,以5个蔗糖代谢关键酶基因及1个耐寒性相关基因为靶标基因,通过设计正向锚定引物和9个随机引物,采用其中34个多态性好的引物组合,对33份包括我国主栽品种、新选育品种（系）和新引进的重要种质,进行TRAP标记分析。共产生579个条带,其中多态性条带288条,占49.74%。基于靶标基因的遗传距离幅度为0.26~0.63,UPGMA 聚类分析显示,在GD为0.52水平上,可将33个样本分为4类,其中ROC系列品种靶标基因相异系数小。基于靶标基因TRAP标记的聚类结果,不能完全反映血缘关系的远近,但能揭示基于不同基因型蔗糖代谢关键酶家族基因多态性的差异程度。同时,也发现了一些较特异的种质,为应用分子标记数据指导甘蔗高糖及抗寒杂交育种的亲本选择与组合配置积累了基础资料。此外,本研究结果同样显示了TRAP标记具有稳定性、高效性和易操作性的特点,暗示其在甘蔗分类、重要性状标记等方面,具有很大的应用潜力。研究结果具有重要的理论意义和实践价值。 相似文献
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Field observations indicate that boron (B)‐toxicity symptoms may occur in citrus plants from inappropriate foliar spraying or overfertilizing with B especially under low‐rainfall conditions, where B can accumulate to levels that become toxic to plant growth. Previous work has indicated that different rootstocks can greatly influence the scion's tolerance to B toxicity, however, little is known about the response of different citrus scion–rootstock combinations to excess‐B conditions. In the present study, we investigated the effects of excess B on plant growth, gas exchange, B concentration, and distribution of four scion–rootstock combinations, Newhall and Skagg's Bonanza navel orange (Citrus sinensis Osb.) scions grafted on Carrizo citrange (C. sinensis L. Osb. × Poncirus trifoliata L. Raf.) and Trifoliate orange (Poncirus trifoliata L. Raf.) rootstocks. One‐year‐old plants of the four scion–rootstock combinations were grown for 183 d in sand–perlite (1 : 1, v/v) medium under greenhouse conditions. The plants were irrigated with half‐strength Hoagland's nutrient solution containing two B concentrations, 0.25 (control) and 2.50 (excess B) mg L–1. It was found that, apart from the combination of Newhall grafted on Carrizo citrange, the dry weights in various parts of the other three combinations were reduced by the excess‐B treatment. Furthermore, the plants of Skagg's Bonanza grafted on Carrizo citrange showed the highest growth reduction amongst the four scion–rootstock combinations. In most cases, the greater reductions in dry weight were found in roots as compared to the other plant parts under excess‐B conditions, indicating that roots were more sensitive to B toxicity than the other tissues. In the case of Newhall plants grafted on Carrizo citrange, the entire plant growth was increased by excess‐B treatment. Boron concentrations in all plants parts increased significantly by increasing the B supply in the nutrient solution. Leaves were the dominant sites of B accumulation and showed the greatest increase in B concentration compared to the other plant parts, as B concentration in the nutrient solution increased. Our results indicate that the combination of Newhall grafted on Carrizo citrange was more tolerant to B toxicity, while the combination of Skagg's Bonanza grafted on Carrizo citrange was relatively more sensitive to B toxicity, in comparison with the other scion–rootstock combinations. However, Newhall plants contained more B in leaves and in roots than Skagg's Bonanza plants when they were both grafted on Carrizo citrange, indicating that the mechanism underlying such great differential growth responses of the two scion–rootstock combinations to B toxicity may not be associated with B exclusion from roots or reduced translocation of B to shoots. Furthermore, B distribution in different plant parts implied that the mechanism was also unlikely related to altered distributions of accumulated B in plant tissues. However, inherent ability to tolerate excessive B concentration in plant tissues may be involved in B tolerance. 相似文献
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为筛选高油酸花生萌发期耐冷鉴定指标,构建高油酸花生萌发期耐冷性综合评价体系,挖掘高油酸花生耐冷种质资源。本研究利用隶属函数法、主成分因子分析法、相关性分析及聚类分析法对56份高油酸花生种质资源进行耐冷性综合评价及耐冷种质筛选。结果表明,11个耐冷鉴定指标按贡献率大小依次为露白萌发因子、发芽时间因子及子叶鲜重因子,发芽指数及萌发耐冷指数可以作为高油酸花生萌发期耐冷性的最优鉴定指标,高油酸花生种质资源萌发期耐冷性强弱受多指标影响。高油酸花生萌发期耐冷性状综合评价D值范围为0.080~0.754,均值为0.497,不同高油酸花生品种萌发期耐冷性存在较大差异。56份高油酸花生种质资源分为5个耐冷级别,筛选到萌发期耐冷较强材料1份、中等耐冷材料20份、耐冷较差材料29份、耐冷差材料5份及冷敏感型材料1份。本试验筛选到的耐冷种质可以作为高油酸花生耐冷育种和耐冷机理的研究材料。本研究为探明高油酸花生种质资源耐冷性提供了理论参考。 相似文献