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11.
近15年国家自然科学基金稻、麦类作物遗传育种领域项目申请情况分析 总被引:1,自引:0,他引:1
国家自然科学基金是国家支持基础研究的主要渠道之一。本文以15年(1998—2012年)来国家自然科学基金中稻、麦类作物遗传育种面上类项目申请数据为依据,对稻、麦类作物遗传育种学研究的现状与趋势从研究领域和研究层次2个维度进行了深入分析。分析数据显示,15年来稻、麦类各类型项目申请量呈上升趋势,其中稻类项目的申请总量高于麦类项目。从研究领域来看,稻类研究项目申请量最多的是发育生物学,占稻类申请量的37.4%;其次是抗性,占27.6%。麦类作物研究主要集中在抗性研究领域上,占麦类申请量的38.1%;其次是发育及品质,分别占23.7%和21.5%。从研究层次来看,随着水稻基因组测序的完成,稻类研究领先于小麦研究。稻类研究项目申请量最多的基因克隆与功能分析,占稻类申请量的41.6%;其次是分子标记与基因定位,占28.8%。麦类研究申请量最多的是分子标记与基因定位,占麦类申请量的36.5%;其次是基因克隆与功能分析,占28.2%。综合国内外研究现状,建议今后在继续加强对围绕高产、优质、高效、抗逆等研究持续资助的基础上,积极支持将基因组学、生物技术和生物信息学与传统作物学相结合的基础研究。 相似文献
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粘类小麦雄性不育系F_1结实性状的遗传分析 总被引:1,自引:0,他引:1
采用MINQUE统计方法、加性-显性(AD)及其与环境互作的遗传模型,对粘类小麦雄性不育系和恢复系杂交F1小穗两边结实数、中间结实数等结实性状进行了分析。结果表明,粘类小麦雄性不育系育性恢复性主要以加性效应为主,其次是显性效应,加性方差占表现型方差的比例变幅为38%~48%;不育系(V)-90-110、(Ven)-90-110、(K)-224、(V)-224所配制的组合,在2个结实性状上,包括国内法、国际法,平均结实率均具有正向显著或极显著的加性效应,亲本5253、02-7-215、00-6-247、M8003具有使不育系恢复度提高的加性效应;双亲加性效应高的组合多数表现出其显性效应比较差;国际法恢复度高的组合(K-224×5253),究其原因是双亲国际法恢复度的加性效应高,尤其亲本5253国际法恢复度的加性效应在供试材料中是最高的,其显性效应也较高(36.14%);粘类小麦雄性不育系杂交结实率的高低与环境的互作相对较小,育性恢复性在年份间的表现比较稳定。 相似文献
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A study was conducted to understand the genetics of rate limiting disease reaction to Alternaria solani in tomato. The results from χ2 analysis and Castle Wright estimation revealed that resistance is an oligogenic character controlled by two to few genes.
In general, the results for predominant gene effects reveal that both additive and non-additive effects are involved in the
inheritance of early blight resistance. The results for predominant gene effects obtained for various crosses studied are
discussed along with their implications for improvement of this trait. 相似文献
16.
A. D. Munshi Bishwajit Panda Bikash Mandal I. S. Bisht E. S. Rao Ravinder Kumar 《Euphytica》2008,164(2):501-507
The genetics of resistance to Cucumber mosaic virus (CMV) in Cucumis sativus var. hardwickii R. Alef, the wild progenitor of cultivated cucumber was assessed by challenge inoculation and by natural infection of CMV.
Among the 31 genotypes of C. sativus var. hardwickii collected from 21 locations in India the lowest mean percent disease intensity (PDI) was recorded in IC-277048 (6.33%) while
the highest PDI was observed in IC-331631 (75.33%). All the four cultivated varieties (DC-1, DC-2, CHC-1 and CHC-2) showed
very high PDI and susceptible disease reaction. Based on mean PDI, 8 genotypes were categorized as resistant, 13 as moderately
resistant, 9 as moderately susceptible and one as susceptible. A chi-square test of frequency distribution based on mean PDI
in F2 progenies of six resistant × susceptible crosses revealed monogenic recessive Mendelian ratio 1(R):3(S) to be the best fit.
This monogenic recessive model was further confirmed by 1(R):1(S) ratio as the best fit for back cross with resistant parent
and no fit for either 3:1 or 1:1 in the back cross with the susceptible parent. The results revealed that CMV resistance in
C. sativus var. hardwickii was controlled by a single recessive gene. Considering the cross compatibility between C. sativus var. hardwickii and cultivated cucumber, the resistance trait can be easily transferred to cultivated species through simple backcross breeding. 相似文献
17.
Introduced pests threaten many species and their control is generally beneficial for conservation, particularly on islands where complete eradication is possible. Unfortunately on ‘nearshore’ islands neighbouring source populations exist and unaided reinvasion is likely. Pest control programmes at these sites thus require a metapopulation context to adequately manage movements between source and sink populations. We investigated the ecology of introduced ship rats (Rattus rattus) on a nearshore island, and gene flow with adjacent mainland populations, in order to understand the metapopulation dynamics and relative levels of pest control required within the landscape. We sampled the entire population by trapping (n = 30), achieving eradication, and found a low rat density (3.2 ha−1) indicative of a sink population. Seed and other plant material constituted the major dietary component of rats. Despite its proximity to mainland source populations, the island population was genetically distinct with reduced allelic diversity caused by a recent reinvasion founder effect. Genetic analyses also detected recent migrants between the populations. In contrast, two mainland populations separated by a similar distance displayed complete genetic mixing. The small water gap therefore provides a sufficient barrier to lower the migration rate to the island and delay reinvasion, which nonetheless eventually happens. In order to maintain nearshore islands pest-free, conservation management will require a metapopulation approach simultaneously focusing on both island and source population pest control. 相似文献
18.
Sample populations of 157 Cannabis accessions of diverse geographic origin were surveyed for allozyme variation at 17 gene loci. The frequencies of 52 alleles were subjected to principal components analysis. A scatter plot revealed two major groups of accessions. The sativa gene pool includes fiber/seed landraces from Europe, Asia Minor, and Central Asia, and ruderal populations from Eastern Europe. The indica gene pool includes fiber/seed landraces from eastern Asia, narrow-leafleted drug strains from southern Asia, Africa, and Latin America, wide-leafleted drug strains from Afghanistan and Pakistan, and feral populations from India and Nepal. A third putative gene pool includes ruderal populations from Central Asia. None of the previous taxonomic concepts that were tested adequately circumscribe the sativa and indica gene pools. A polytypic concept of Cannabis is proposed, which recognizes three species, C. sativa, C. indica and C. ruderalis, and seven putative taxa. 相似文献
19.
从注重实验室建设、精选实验内容、改进实验教学方法、完善考核体系等方面,阐述了遗传学实验教学的改革,并分析了所取得的效果。 相似文献
20.
Study on the Genetics and Development of Fiber Pigments and Color Deviation After Wetting Process of Naturally Colored Cotton 总被引:1,自引:0,他引:1
The genetic control of fiber pigment color in naturally colored cotton was studied. The expres-sion of brown and green fiber color was controlled by incompletely dominant single genes and incompletelydominant major genes, respectively. Production and accumulation of the fiber pigment were related to specialexpression of enzymatic genes for pigment synthesis in fiber cells. At the stage of fiber lengthening, naturallycolored cotton, like white cotton, appeared purely white. But when fiber cell walls entered the thickeningstage, pigment appeared by degrees. When the fiber was completely matured (on boll dehiscence), the colorreached its darkest level. After wetting process treatment, the hues of the fiber pigment changed in regularpatterns. The hue circle for brown and green cotton changed in the opposite direction with wetting processtreatment. In general, the treated cotton color and luster became dark and vivid, and this trend provided the possibili-ty for enhancing the fiber quality by suitable enviromnental friendly finishing. The analysis showed that the color andluster of the cotton may be controlled by a series of pigments which show different chemical performance. 相似文献