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Heterosis and heterotic patterns of maize germplasm revealed by a multiple-hybrid population under well-watered and drought-stressed conditions 
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下载免费PDF全文 SANG Zhi-qin ZHANG Zhan-qin YANG Yu-xin LI Zhi-wei LIU Xiao-gang XU Yunbi LI Wei-hua 《农业科学学报》2022,21(9):2477-2491
Understanding the heterosis in multiple environments between different heterotic groups is of fundamental importance in successful maize breeding. A total of 737 hybrids derived from 41 maize inbreds were evaluated over two years, with the aim of assessing the genetic diversity and their performance between heterotic groups under drought-stressed (DS) and well-watered (WW) treatments. A total of 38 737 SNPs were employed to assess the genetic diversity. The genetic distance (GD) between the parents ranged from 0.05 to 0.74, and the 41 inbreds were classified into five heterotic groups. According to the hybrid performance (high yield and early maturity between heterotic groups), the heterosis and heterotic patterns of Iowa Stiff Stalk Synthetic (BSSS)×Non-Stiff Stalk (NSS), NSS×Sipingtou (SPT) and BSSS×SPT were identified to be useful options in China's maize breeding. The relative importance of general and specific combining abilities (GCA and SCA) suggests the importance of the additive genetic effects for grain yield traits under the WW treatment, but the non-additive effects under the DS treatment. At least one of the parental lines with drought tolerance and a high GCA effect would be required to achieve the ideal hybrid performance under drought conditions. GD showed a positive correlation with yield and yield heterosis in within-group hybrids over a certain range of GD. The present investigation suggests that the heterosis is due to the combined accumulation of superior genes/alleles in parents and the optimal genetic distance between parents, and that yield heterosis under DS treatment was mainly determined by the non-additive effects. 相似文献
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Effective cumulative temperature (ECT) after heading would be a more reasonable parameter for seed sampling of pre-harvest sprouting/seed dormancy (SD) tests in segregating populations than the days after flowering. SD is an important agronomic trait associated with grain yielding, eating quality and seed quality. To identify genomic regions affecting SD at different grain-filling temperatures, and to further examine the association between SD and ECT during grain-filling, 127 double haploid (DH) lines derived from a cross between ZYQ8 (indica)/JX17 (japonica) by anther culture were analyzed. The quantitative trait loci (QTLs) and their digenic epistasis for SD were identified using a molecular linkage map of this population. A total of four putative QTLs for SD (qSD-3, qSD-5, 6 and 11) were detected on chromosomes 3, 5, 6 and 11, together explaining 41.4% of the phenotypic variation. Nine pairs of digenic epistatic loci were associated with SD on all but chromosome 9, and their contributions to phenotypic variation varied from 2.87%–8.73%. The SD QTL on chromosome 3 was identical to the QTLs found in other mapping populations with different genetic backgrounds, which could be a desirable candidate for gene cloning and marker-assisted selection in rice breeding. 相似文献
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我国农业必须走依靠科技创新大幅度提高水的利用效率、发展节水型高效农业的内涵式增长道路、从传统的粗放型灌溉农业和旱地雨养农业向现代高效节水型灌溉农业、节水型旱作农业和节水型生态农业转变。为此，在“九五”期间已取得的节水农业科技创新成效基础上，国家应加大对节水农业科技发展的支持力度，强化节水农业科技基础条件建设，完善节水农业技术创新平台，加快节水农业科技创新步伐，尽快建立健全具有中国特色的节水农业技术体系与模式，实现我国节水农业的跨越式发展。 相似文献
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籼粳稻间苗期耐冷性的遗传研究 总被引：19，自引：1，他引：19
利用6个籼粳稻间杂交组合研究了苗期耐冷性的遗传。根据3叶期10℃/6℃（昼/夜）处理7天后的卷叶程度，各组合籼粳稻间耐冷性的差异均由两对重复基因所控制，耐冷性为完全显性。F#-2耐冷类型的植株中部分为籽粒较长、稃毛较少的偏籼类型，表明利用籼粳杂交改良籼稻品种的苗期耐冷性是可行的。 相似文献
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在加性-显性模型的基础上提出了检测基因分散态组合的三种方法:(1)检验F_2表型方差与环境方差的同质性以及六个群体P_1,P_2,F_1,F_2,B_1(F_1×P_1)和B_2(F_1×P_2)间方差的同质性,(2)检验上述家系均值间的差异显著性,(3)比较从分离世代经分裂选择所获两类极端品系间组合与基因分散的原始亲本间组合在遗传参数估计值上的差异.通过加性-显性模型检验、有效因子数和基因联合-分散度的估计以及重组近交系分离极限的预测,这些方法所检测到的基因分散态组合可进一步用于揭示数量基因的遗传特性.讨论了这类信息在植物改良中的应用. 相似文献
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籼粳交加倍单倍体后代性状遗传的研究 总被引：11，自引：0，他引：11
对一个典型的籼/粳组合、窄叶青8号/京系17的F1花药进行培养,所获二倍体花粉植株除约20%自然结实率为0外,其余植株的结实率在1%至正常结实之间,65%株系在75%以上,并稳定地传至自交后代。对130多个加倍单倍体(DH)多种性状的遗传进行了研究与分析,结果表明,花药培养可以克服籼/粳后代包括育性在内的各种性状长期分离不易 相似文献
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水稻亚种间的亲和性研究 总被引：10，自引：0，他引：10
对160个亚种间F_1结实率的分析表明,籼稻 IR58和二九丰、粳稻秀水117和T8340具有较好的亚种间亲和性。43个粳稻品种分别与 IR58和二九丰测交,其成对 F_1的结实率随粳稻品种不同而出现 IR58/粳高于二九丰/粳、二九丰/粳高于 IR58/粳或两者相似的情形,其最大差值可达72.6个百分点。10个籼稻品种分别与秀水117和 T8340杂交,其F_1结实率均以秀水117/籼较高,成对F_1结实率的最大差值可达39.6个百分点。这表明不存在对亚种间品种均表现亲和性的“广亲和”品种,亲和性的广与狭只是相对的,既有一般亲和性,又有特殊亲和性。本研究发现4个受测品种的亲和性与色素基因之间不存在连锁或相关关系。 相似文献
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水稻糯质基因对产量构成性状的影响 总被引：12，自引：0，他引：12
利用3对糯与非糯近等基因系研究了糯质基因(wx)对产量构成性状的影响。3对糯与非糯品系均仅具有千粒谷重这一产量构成性状有极显著的差异,糯稻比非糯稻降低7.3—9.7%,降低的原因并非由于谷粒体积的减小而是由于糙米粒重和谷粒比重的降低。糯稻与非糯稻具有相同的同化产物库容,但由于灌浆不充实,米粒较小,导致糯稻谷壳内余留较 相似文献
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水稻茎叶形态性状的简化三重测交分析 总被引：4，自引：0，他引：4
以H1459和乐一为测验系L_1和L_2,分别与泸红早等22个早籼品种进行简化三重测交(sTTC),考查了12个茎叶形态性状。其中,剑叶宽、倒2叶宽、倒3叶宽,倒2节间长和基部节间粗在两个测验系中表现为极端类型,倒3叶长和剑叶夹角在两个测验系间可能存在由于同效基因分散分布引起的真实遗传差异。对上述7个性状的遗传分析表明,基部节间粗 相似文献