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在不同生长条件下种植木豆雄性不育系和保持系,开花结荚期分别观察它们的开花数和结荚数,同时计算结荚率.通过分析表明,木豆为常异花授粉作物,天然异交率为21.2%,主要传粉媒介为昆虫,风媒介对其几乎没有影响.这一特性有利于木豆的遗传改良和杂交种的培育.通过放养蜜蜂等途径提高木豆天然异交率,可省去人工授粉,增加木豆结荚率,提高木豆杂交种产量.防虫网隔离可生产纯合的木豆种子,并可以提高开花数和结荚数. 相似文献
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春蚕豆异交率测定研究 总被引：1，自引：0，他引：1
蚕豆属常异花授粉作物,其异花程度的高低常因品种、气候条件、地区、蜂源及栽培田块不同而异.掌握蚕虫自然异交率与这些因素的关系,对育种、繁种保纯和高产栽培都至关重要.我所于1996-1997年开展了春蚕豆异交率测定研究. 1材料与方法父本为白皮、黑脐的临蚕二号,母本为红皮、白脐的临夏白脐红和红皮、白脐的和政尕红蚕. 试验I:选择14m×21m的地块,按2m×3m划成49个小区,四周种植白皮蚕豆,中间等行距种植9个小区红皮蚕豆,每小区种4行. 相似文献
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通过豆薯不同花色性状品种（系）的自然异交试验,以及对虫媒传粉异交的调查研究表明：豆薯天然异交率为O．26％-4．16％,为自花授粉作物。提出在豆薯种子生产上,单纯的隔离距离应在50m以上为宜。观察到在豆薯开花期蜜蜂等昆虫的活动不是以采粉为目的,但从事豆薯种子生产时,还应根据蜜蜂等昆虫的活动密度加大隔离距离。 相似文献
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栽培因素对重庆稻茬免耕蚕豆影响初探 总被引：3，自引：3，他引：0
为了解不同栽培因素对重庆地区稻茬免耕条件下蚕豆生产的作用,采用四因素四水平正交试验,研究品种、密度、施肥和播期对稻茬免耕蚕豆产量和农艺性状的影响。结果表明：品种是影响其产量形成的最主要因素,不同品种对重庆稻闲田这种高湿环境的适应能力差异极显著(P<0.01);影响蚕豆株高的主要因素是品种自身的遗传因素和播期因素;密度、品种、施肥均对蚕豆单株粒数有显著影响(P<0.05);影响蚕豆百粒重主要由品种自身的遗传因素决定。综合考虑,重庆地区稻茬免耕蚕豆的最优措施为：‘苏03021’在10月22日播种,密度为12.7×104株/hm2,施用过磷酸钙450 kg/hm2+尿素75 kg/hm2,此时产量可达2725.2 kg/km2。 相似文献
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玉米杂交制种过程中 ,异交结实率的高低直接受品种特性、外界环境的制约。在多年的玉米制种实践中 ,笔者常发现一些植株果穗秃顶、秃根和缺粒现象 ,有的甚至全穗不结实 ,一般减产 10 %～ 30 % ,高的达 5 0 %～70 % ,严重影响制种产量。对此必须要高度重视 ,找准症结 ,充分利用有效的技术措施予以解决。1 玉米异交结实的制约因素1.1 品种特性对异交结实的影响 :1亲本对高温干旱敏感 ,抗性差 ,雄花败育严重 ,花粉少而生活力弱 ,其异交率自然就低 ,这是导致玉米异交结实率下降的内在因素。2亲本果穗苞叶紧且长 ,花丝吐出慢而不齐 ,造成授粉不… 相似文献
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为研究不同整枝打顶方式对不同蚕豆品种农艺性状和产量的影响，总结不同品种的最适整枝打顶方式，以‘成胡10号’、‘成胡18’、‘成胡19’和‘成胡25’为材料，对每个蚕豆品种分别设置4种整枝打顶处理方式：全处理、去主茎、去无效枝、打顶，分析不同处理对不同蚕豆品种的农艺性状和各产量构成因素的影响。结果表明，打顶处理可有效控制不同蚕豆品种的株高；‘成胡10号’在打顶处理下的2年平均鲜荚产量较对照增产20.9%，鲜籽粒产量较对照增产25.7%，均显著高于对照；‘成胡19’在去主茎处理下，2年平均鲜荚产量增产61.2%，鲜籽粒产量增产35.5%，均显著高于对照；各整枝打顶处理方式对‘成胡18’的鲜食产量及其构成因素无明显影响；打顶处理对提高鲜食专用型‘成胡25’的百粒重及出籽率有一定促进作用。综上，整枝打顶对蚕豆的增产效应在不同蚕豆品种及不同整枝打顶方式间均有所差异，针对不同专用型品种，可选择性针对某些产量性状而采取适宜的整枝打顶方式，以获得更高的经济效益。 相似文献
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人工控制条件下大豆不育系昆虫传粉技术研究 总被引：7，自引：1，他引：6
在人工控制条件下借助昆虫为大豆不育系传粉是杂交大豆育种的重要手段。试验以不同大豆不育系为材料,在网室、温室以及海南等条件下对蜜蜂、熊蜂和苜蓿切叶蜂的传粉效果进行了研究。结果表明,蜜蜂、熊蜂和苜蓿切叶蜂均可作为大豆不育系的传粉媒介,以苜蓿切叶峰的传粉效率最高。冬季在温室内不宜以昆虫作为传粉媒介繁育不育系。在海南人工加光能够满足大豆正常生长发育的条件下,可以在网室内借助苜蓿切叶峰传粉繁育不育系或生产F1种子。不同基因型大豆不育系间其异交结实程度存在着显著差异。 相似文献
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Variation in outcrossing rate and genetic structure on six cultivars of Vicia faba L. as affected by geographic location and year 总被引：1，自引：0，他引：1
The present study was conducted to evaluate the importance of two environmental factors, year and geographic location, on the cultivar outcrossing rate and genetic structure of Vicia faba L. Under natural field conditions. Outcrossing rates were estimated for six cultivars using isozyme markers, the mixed mating model and the multilocus method. The genetic structure was described by Wright's fixation index and the inbreeding equilibrium coefficient. Faba bean outcrossing rate, as measured by multilocus estimates was relatively invariable among cultivars within locations. Our results suggest substantial variation in outcrossing rate associated with geographic location (Mediterranean subtropical and temperate climates enhancing the cross-pollination). Year variation was far less important than geographic variation. 相似文献
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Six faba bean gene-pools were cultivated to develop locally adapted genetic material for low-input (LI) systems that take advantage of the observed benefit of LI agriculture in pollinator density and diversity. Bee pollinators intensify selection on floral traits important in attraction and mechanical-fit but may also select for traits that increase seed set through outcrossing and aided selfing. Our research is focused on examining the impact of natural selection in crop performance under different pollination management strategies, taking into account traits relevant for the inter-phase plant and pollinator. Architectural and floral patterns are the result of natural selection and they reflect local adaptation to factors of the environment and adaptations to differences in pollination management strategy. However, seed production patterns seem to be affected by natural selection in an inconsistent way. Principal Component models showed a large proportion of the temporal variation accounted by plant height and number of open flowers and by floral shape and sexual dimensions. Discriminant Analysis indicated that plant architecture and floral traits related to pollinators are also the result of selection for particular patterns in each pollination management strategy. Flowers with an increase in the zygomorphy were favored under the open-pollination. Our work confirms the need for careful management of plant-pollinator inter-phase in faba bean breeding for LI systems. 相似文献
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Rice is mainly a self-pollinating crop, but some outcrossing has been reported. Outcrossing with an undesirable donor would lead to the creation of segregants or off-types, which would adversely affect genetic purity and uniformity of the crop. Outcrossing rates in rice under field conditions were investigated using cultivar WAB96-1-1 as a pollen donor and WAB56-104, NERICA 2, NERICA 4 and NERICA 7 as pollen recipients. Levels of outcrossing were investigated up to 30 m from the pollen donor. Dominant morphological markers of red kernel colour and pubescent leaves of the donor were used to identify hybrids. A total of 721 134 plants were investigated. There was an average outcrossing rate of 0.7 ± 0.51%, with a potential outcrossing rate of 2.45 ± 0.86%. Outcrossing rates decreased with increase in distance. It ranged from 2.45% at 0.2 m from the donor to 0.05% at 25 m from the donor. Differences were observed between genotypes and seasons. In season 1 the highest average outcrossing rate of 1.2 ± 0.63% was with WAB56-104 and in season 2 it was 1.1 ± 0.69% with NERICA 4. Outcrossing occurred up to 30 m from the donor. This has implications for germplasm management and conservation and the production of high quality seed. Spatial isolation remains the most practical method to prevent undesirable gene flow. The study indicated that red kernel colour and leaf pubescence can be used to effectively assess outcrossing under field conditions in rice. 相似文献
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中国蚕豆种质资源ISSR标记遗传多样性分析 总被引：7，自引：0，他引：7
利用ISSR标记对中国18个省(区)的527份春播区和秋播区蚕豆资源的遗传多样性与亲缘关系进行分析。结果表明,11个ISSR引物共扩增出278条清晰的条带,其中多态性条带268条(占96%)。不同地理来源蚕豆资源群间的基因多样性指数在0.1267~0.2509之间,平均为0.1716;Shannon指数范围为0.1932~0.3767,平均为0.2608。两指数均以内蒙古资源群最高,云南和甘肃资源群次之,江西资源群体最低。非加权配对算术平均法(UPGMA)的聚类分析和二维主成分分析(PCA)结果表明,中国春播区和秋播区蚕豆资源明显不同,浙江和四川的资源形成独立的组群,明显不同于其他省份,其遗传背景独特,有待进一步研究。中国蚕豆种质资源遗传多样性差异和遗传关系与其生长习性、生态分布及地理来源密切相关。 相似文献
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Outcrossing rates of Cuphea lanceolata Ait., a new Dilseed crop, have not been estimated; however, this species is known to be insect-pollinated, self-compatible, and autosterile. We used five allozyme loci and the mixed mating model to estimate the outcrossing rates of experimental populations of Cuphea lanceolata Ait. grown at Corvallis, Oregon in 1987 and 1988. Populations were grown using densities of one and 27 plants m?2. Multilocus out-crossing rate estimates of populations grown at low and high density ranged from 0.61 to 0.85 and 0.93 to 0.94, respectively. Density caused differences may be caused by differences in pollinator movement. In open plantings, e.g., space-plant nurseries, selfing rates are increased by increased within plant pollination by bumblebees, the primary pollinators of C. lanceolata in temperate zones. The movement of pollinators between plants is enforced in dense plantings. We found C. lanceolata is predominantly al-logamous, but selfing rates as great as 39.0 % were observed among space-plants; thus, the progeny of an open-pollinated individual plant grown in this type of nursery is a mixed half-sib and S1 family. Maximum outcrossing can be achieved by using dense plantings. 相似文献
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Physiological and Molecular Characterization of Faba bean (Vicia faba L.) Genotypes for Adaptation to Drought Stress 
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下载免费PDF全文 S. S. Alghamdi A. M. Al‐Shameri H. M. Migdadi M. H. Ammar E. H. El‐Harty M. A. Khan M. Farooq 《Journal of Agronomy and Crop Science》2015,201(6):401-409
Faba bean (Vicia faba L.) is one of the most important and drought sensitive grain legumes. Drought stress is thus one of major constraints in global faba bean production. In this study, twenty local and exotic faba bean genotypes were characterized on physiological and molecular basis. Seeds of faba bean genotypes (six per pot) were sown in poly venyl chloride pots. After seedling emergence, soil moisture was maintained at 100%, 50% and 25% of field capacity designated as well watered, moderate drought and severe drought, respectively. Drought stress significantly influenced the leaf area, leaf temperature, stomatal conductance, relative leaf water contents, grain yield and water‐use efficiency. Faba bean genotypes also differed for the leaf area, leaf temperature, relative leaf water contents, grain yield and water‐use efficiency. Faba bean genotypes Kamline and L.4 were better equipped to curtail water loss, maintain tissue water status, produce stable grain yield and had better water‐use efficiency under mild and severe drought stress, and may be used in breeding programmes. Amplified fragment length polymorphism markers showed high potential in detecting polymorphism and estimating genetic diversity among faba bean genotypes. Unweighted pair group method with arithmetic mean cluster analysis of the genotypes illustrated considerable association between molecular diversity, genetic background and geographic origin. In crux, high polymorphic rate and polymorphism information content values, together with the low genetic similarity observed among tested genotypes suggests a high level of heterogeneity, which may be used in breeding programmes to assemble different drought tolerance mechanisms in one genotype. 相似文献
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Summary To assess the feasibility for synthetic varieties of Vicia faba L., 108 faba bean genotypes were screened for cross-fertilization rate in five field experiments carried out in 1989 and 1990 at Wageningen.Significant genotypic differences were observed for outcrossing rate, which ranged from 1 to 55%. These percentages, however, are thought to be not high enough for a commercially feasible production of synthetic varieties.The inheritance of cross-fertilization rate, determined by testing the F4 generation of a cross between two inbreds, both with high outcrossing rates, appeared to be of a polygenic nature, as was indicated by the wide variation in, and the continous distribution of, the cross-fertilization rates. Among the F4 lines tested some had a significantly higher cross-fertilization rate than the parents. However, this difference was not found when these lines were retested, indicating that possibilities for successful selection for higher outcrossing rates might be limited. 相似文献
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国内外蚕豆核心种质SSR遗传多样性对比及微核心种质构建 总被引：3，自引：0，他引：3
运用24对SSR引物, 对国内外1075份初级地理蚕豆核心种质的遗传多样性分析显示, 等位变异数、有效等位变异数及Shannon’s信息指数分别为8.54、2.26和1.02;对全部参试资源进行聚类分析, 没有发现明显的群体结构, 表明初级地理核心种质的代表性较好, 遗传背景较广泛。之后采用每个类内随机抽样的方法构建含有129份国内资源和63份国外资源的蚕豆微核心种质, 等位基因变异数、有效等位变异数和Shannon’s信息指数的保留比例分别为87.32%, 101.26%, 101.82%;经t检验得出微核心种质与全部参试资源群体间遗传多样性差异不显著, 表明构建的微核心种质的遗传多样性可以代表初级地理蚕豆核心种质。 相似文献
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Outcrossing rates of barley landraces from Syria 总被引：1，自引：0，他引：1
Diversity levels in populations of barley landraces may be influenced by varying levels of natural outcrossing caused by environmental conditions. Outcrossing was studied in 10 accessions of the barley landrace Arabi Aswad from different environments in Syria. Electrophoretic variation at two codominant isoenzymes (Est1 and Est2) in six seeds of 50 families per population were analysed and multilocus outcrossing rates calculated. Results were correlated with interpolated environmental conditions. Outcrossing was, on average, 1.7% and not significantly different from the outcrossing rate of wild barley. A significant increase of outcrossing was observed with increasing inter‐annual variation in rainfall and decreasing minimum temperatures of the coldest month. 相似文献
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Fouad Maalouf Jinguo Hu Donal M. O'Sullivan Xuxiao Zong Aladdin Hamwieh Shiv Kumar Michael Baum 《Plant Breeding》2019,138(4):465-473
Faba bean is an important legume crop because of its high‐yield potential and nutrition‐dense grains. There have been significant achievements in faba bean improvement in the last four decades, which led to the doubling of the global yield average. This study reviews the genetic diversity, the breeding methodologies, major achievement on biotic and abiotic traits, and the recent molecular approaches. The high genetic diversity among faba bean accessions has been useful for increasing yield potential of the crop. Substantial increase in yield potential can be gained through the development of cultivars in open pollinated conditions. In the past, many faba bean varieties that are tolerant to abiotic and biotic stresses were released worldwide. The average yield gains varied from 1.65% per year in Syria to 4.17% per year in Ethiopia. The recent advances in molecular technologies will be used to develop more coherent genetic maps, which would also facilitate assembling and ordering genomic scaffolds in a future genome‐sequencing effort and molecular‐breeding approach. 相似文献