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1.
There is a need to evaluate grass varieties under grazing management to allow selection of varieties to increase animal performance. However, the evaluation of animal performance under grazing with each variety is arduous and time-consuming. An alternative is to describe the preference by grazing animals when given a choice of different varieties. Indeed, there is some indications that preference is related to variety characteristics such as leaf content or digestibility, characteristics having also an impact on the level of intake of this variety. However, preference for grass varieties, when sown alone, may not reflect agricultural practice as grasses often occur in mixed swards, associated with white clover. So, the aim of the present work was to determine whether, under grazing management, cattle expressed selections when given a choice of mixed swards in which different perennial ryegrass varieties were grown in association with a common white clover variety at two levels of fertilizer application (60 or 160 kg N ha−1 annum−1). The preference for perennial ryegrass variety per se was then assessed after taking white clover content into consideration. The results show that there were significant differences in preference for perennial ryegrass varieties, per se, even for varieties with the same heading date and ploidy. The effect of white clover cover on sward selection was more marked in swards which received the higher level of nitrogen fertilizer application which may have been related to a more variable white clover content between swards. This suggests that, under low nitrogen fertilizer application, differences in perennial ryegrass varieties preference can be determined in the same experiments as are used to determine ryegrass varieties persistence in association to white clover. Nevertheless, before such ‘variety preference’ tests can be applied in practice, a validation of the possible correlation between ‘variety preference’ and ‘variety intake’ will be necessary. 相似文献
2.
品种遗传多样性和指纹图谱是育种、品种权保护和新品种推广等工作的重要参考和依据。本研究选用38个来自国家甘蔗品种区域试验的甘蔗新品种(系), 以9对AFLP标记扩增出348个位点, 多态性位点248个, 多态性比率为72.26%; 15对SSR标记扩增出180个位点, 多态性位点176个, 多态性比率为97.78%。38个新品种(系)的遗传相似系数分布在0.668~0.847之间, 其箱线图分布特征显示, 其中的FN、MT、YZ、YG、GT等系列品种(系)遗传基础相似。通过UPGMA聚类表明, 可在遗传相似系数为0.732处将38个甘蔗新品种(系)划分为2个群体, 其中福农09-2201和桂糖06-1492作为一个子群体最先被划分出来, 它们在群体中的异质性较强; 另外, 在遗传相似性系数为0.770处划分出一个子群体a, 其中包含参照品种ROC22、福农07-3206、福农40、海蔗22、桂糖09-12、柳城07-150等品种(系)。ROC22具有广适应性和高产高糖等优良特性, 子群体a中的另外几个品种(系)则更有可能拥有这些特性, 具有更高的推广潜力。本研究选择60个SSR位点构建了38个甘蔗新品种(系)的指纹图谱, 对品种鉴定及品种权的保护具有重要作用, 可望直接应用于指导甘蔗种质资源的遗传多样性评价和分子指纹图谱鉴定, 并将为这些品种(系)推广布局或作为杂交亲本利用提供参考和借鉴。 相似文献
3.
系谱分析能够简便有效地阐明育成品种的整体遗传基础,掌握育成品种的遗传基础可揭示品种演变特点,总结亲本选配的经验,并指导育种。本研究对保山市农业科学研究所2000年以后育成的21个大麦系列品种的育种途径及其品种系谱进行分析,结果表明,杂交育种是保山市农业科学研究所大麦育种的主要方法,76.2%的品种是通过杂交育种育成的,23.8%的品种是经过系统选择育种而成。所育成的21个大麦系列品种来源于20个细胞核祖先亲本和10个细胞质祖先亲本。来源于墨西哥的亲本细胞核遗传贡献值最大,为62.35%,表明保大麦系列品种祖先亲本主要来源于墨西哥。来源于墨西哥的亲本‘YS500’、‘V008’、‘8640’、‘Peaosanhos-174’累计细胞核贡献值最大、衍生品种最多,为核心祖先亲本。 相似文献
4.
河南省审定花生品种的指纹图谱构建 总被引：1，自引：0，他引：1
利用14个SSR标记构建了河南省2015年之前选育并审定的90个花生品种的DNA指纹图谱,用14个SSR标记产生的95个多态性位点可将90个花生品种完全区分开,其中84个品种间有≥2个位点的差异,在剩余的3对品种中,每对仅有1个差异位点。聚类分析结果表明,在遗传相似系数0.98处,90个花生品种被聚集成88类,有2对品种分别聚集在一起,是由于它们每一个品种分别以另一个品种作亲本选育而成,仅有1个差异SSR位点,表明所构建的指纹图谱是有效的。以遗传相似系数0.95为划分标准,有74.4%的品种具有特异性,与其他作物相比,河南省育成花生品种总体上亲缘关系相对较近。根据60个SSR标记的群体结构分析,90个花生品种可以分为3个亚群,与根据分枝开花习性和荚果类型的分类相吻合,亚群划分情况与聚类分析结果基本一致。 相似文献
5.
两个低谷蛋白基因插入缺失标记的设计与验证 总被引：2，自引：0，他引：2
低谷蛋白稻米是肾脏病人极有效的食疗辅助品,培育低谷蛋白功能性水稻品种具有重大意义。低谷蛋白基因Lgc1作为培育低谷蛋白功能性水稻品种的优质资源,受到了育种家的青睐。为提高低谷蛋白基因Lgc1分子标记辅助选择的准确性,我们根据其突变体在两个谷蛋白基因GluB4和GluB5间的碱基缺失,设计出了Lgc1基因的插入缺失标记InDel-Lgc1-A和InDel-Lgc1-B。利用InDel标记对W3660(Lgc1低谷蛋白品种)/南粳46(谷蛋白正常品种)的F2分离群体和13份水稻品种进行检测验证。依据其PCR扩增产物的电泳带型,可准确地区分出低谷蛋白纯合基因、谷蛋白正常纯合基因和杂合基因型3种带型,且3种带型与其植株或品种相应的蛋白性状表现完全一致,表明这两对InDel标记可用于Lgc1低谷蛋白基因资源的鉴定以及分子辅助育种。 相似文献
6.
Xiao-Fang Li Zhi-Xia Liu Dong-Bo Lu Yan-Zhuo Liu Xing-Xue Mao Zhi-Xin Li Hua-Jun Li 《Euphytica》2013,192(1):77-86
Multi-genotype varieties can effectively alleviate or reverse the decline of genetic diversity in agriculture caused by the predominant extension of mono-genotype (pure line) varieties of crop plants. We devised a novel breeding strategy for developing multi-genotype varieties of rice from MAGIC lines, which were derived from two convergent crosses among 8 or 12 parental lines, respectively. We found that both multi-genotype varieties and varietal mixtures were superior to their component lines/varieties in both yielding and blast-resistance performances. When the multi-genotype varieties were developed through intensive selection, they displayed comparable or better performance in yielding level and disease resistance in comparison to current leading mono-genotype varieties of rice. A promising multi-genotype variety has been selected over a 2-year regional trial in Hainan province and it will be hopefully granted a varietal-release permit. Multi-genotype breeding may be an alternative and feasible solution to the sustainable development of agriculture. 相似文献
7.
Trygve Berg 《Euphytica》2009,166(3):423-430
Farmers’ seeds are most often lumped together in one broad category called ‘landraces’. But such a category covers variety
types that reflect different levels of farmer involvement. Those differences matters when we discuss such issues as genetic
erosion, on-farm conservation and seed related policies. The term landrace can be traced to the time when ‘modern’ varieties
of cereals were introduced to European farmers in the late nineteenth century. The farmers’ varieties of the time were called
‘landraces’ and understood as seeds adapted to local growing conditions through natural adaptation usually with no intentional
selection. But the term was quickly adopted as generic for all farmers’ varieties including those that are bred and maintained
by active seed selection on-farm. Such farmer-bred varieties are better termed ‘folk varieties’. The article discusses how
interaction of crop characteristics and developing technologies resulted in the evolution of crop varieties as either landraces
or folk varieties. It is argued that vulnerability to different agents of genetic erosion and feasibility of on-farm conservation
are clearly different for the two categories of farmers’ varieties. Likewise seed policies, particularly the issue of Farmers’
Rights would benefit from clarity of type of farmers’ varieties. 相似文献
8.
晋麦63的评价与利用研究 总被引：1，自引：0，他引：1
在抗旱优质高产小麦新品种晋麦63的选育中,选用北部和黄淮两大麦区的优异种质,使目标性状得到了有效的组合,采用水旱交叉选育法,实现了自然选择、人工选择和定向培育的有机结合,提高了选种质量和效率。利用该品种进行广泛组配,获得其遗传特点为抗旱性、丰产性及综合农艺性状优,稳产适应性好,遗传传递力强,配组范围广,不良连锁基因易打破。利用其做亲本已选育出4个抗旱高产稳产广适小麦新品种,其中有3个品种同时通过国家审定。同时还育成了一批苗头品系和优异种质。实践表明:晋麦63不仅是一个优良的种植品种,而且是一个优异的亲本材料。 相似文献
9.
磷营养对粳稻根部性状的影响 总被引：1，自引：0，他引：1
黑龙江省三江平原已垦和未垦低磷土壤面积在300万hm2左右,筛选耐低磷水稻品种是提高这类土壤的水稻生产潜力的重要途径。研究选用生产上已广泛应用的5个水稻品种,采用不同磷水平砂培法,分不同时期调查水稻根部性状。结果表明,在不同磷营养水平下品种间根部性状有显著差异。品种根部性状值相对较大的材料为耐低磷种质,对磷不敏感的材料为筛选耐低磷种质的首选种质。根部性状中,总根长、根数对磷的最敏感期为分蘖盛期,根重对磷的最敏感期为抽穗期,因此,调查根部性状的适宜时期为水稻分蘖盛期和抽穗期前后;在低磷水平下,根数、根重是筛选耐低磷品种的两个重要指标。水稻植株磷含量在同一磷水平内,不同品种虽有差异,其与生物产量无关。植株吸磷量随磷水平的提高而增加的途径之一是通过根表面积的增大而致。筛选耐低磷种质的适宜磷水平为3mg/kg。研究为筛选大量品种初步筛选出耐低磷种质提供依据和可行的方法。 相似文献
10.
Pedro Revilla Laura Campo José Ignacio Ruiz de Galarreta Domingo Rios Ángel Álvarez Jesús Moreno-González Amando Ordás Rosa Ana Malvar 《Euphytica》2017,213(6):123
Germplasm collections often include open-pollinated varieties from diverse latitudes and climatic areas that cannot be correctly conserved in a single environment. The objective of this research was to investigate if open-pollinated maize varieties from diverse latitudinal and climatic conditions could be conserved in a single location. Twelve varieties from the humid Spain, the dry Spain, and the Canary Island were multiplied in three locations from the humid Spain, one from the dry Spain, and one from the Canary Islands. Hand pollinations were made in 100-plant plots following a randomized complete block design with two replications in five locations during two years. Differences between origins and between varieties were significant for most traits, including those related to growth cycle (male and female flowering and grain moisture). The varieties from each latitudinal and climatic origin did not behave as a consistent germplasm block; contrarily, the location × variety interaction was significant for most traits. The varieties from the humid Spain maintained their ranks of growth cycle across locations and differences between varieties were more important in the dry Spain. The growth cycle of the Canarian varieties was completely different in the dry Spain. We can maintain the varieties from any Spanish environment and latitude at any location, but most varieties could be modified by natural selection for adaptation. 相似文献
11.
Marianne Elias Doyle McKey Olivier Panaud Marie Charlotte Anstett Thierry Robert 《Euphytica》2001,120(1):143-157
In this paper we present original data on morphological and genetic diversity of cassava managed by the Makushi Amerindians
from Guyana. Although they propagate cassava exclusively vegetatively by means of stem cuttings, many Amerindian farmers also
use and multiply volunteer plants grown from seeds produced by sexual reproduction. Morphological characters were recorded
for 29 varieties cultivated by the Makushi and two populations of plants originating from volunteer cassava seedlings. Genetic
characterisation with AFLP markers was available for 21 of the examined varieties. The morphological and agronomic characters
were highly variable among varieties. Every variety could be differentiated from any other one, except for one pair of varieties.
However, high intra-varietal variability existed, which might lead to confusions between phenotypically similar varieties
by the Makushi. Seedlings were on average different from the pool of the varieties studied, but 67% were found to resemble
closely enough one of the varieties to be liable to be assigned to it. Confusion between very similar varieties, as well as
assignment of seedlings to a variety, should generate genetic variability within varieties, which was detected with AFLP markers.
As in other sites in Amazonia, there was only a weak correlation between inter-varietal distances assessed with molecular
and with morphological markers, suggesting that diversification of morphological characters has taken place repeatedly and
independently across the Amazonian range of the crop. Diversifying selection, exchanges of varieties between farmers, and
incorporation of sexually produced volunteer plants are key mechanisms responsible for the high diversity observed. Strategies
of conservation of genetic resources should take these dynamic processes into account.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
12.
This paper describes how plant breeders and farmers worked together to produce improved varieties of maize for the low-resource
farmers of the Panchmahals district of Gujarat, India. Initially, farmers tested a range of maize varieties in a participatory
varietal selection (PVS) programme. However, none of these proved to be very popular with farmers, although farmers who had
more fertile fields adopted the variety Shweta from Uttar Pradesh. Hence, in 1994 a participatory plant breeding (PPB)programme
was begun to generate new, more appropriate varieties. Yellow- and white-endospermed maize varieties were crossed that had
been either adopted to some extent following PVS or had attributes, such as very early maturity,that farmers had said were
desirable. In subsequent generations, the population was improved by mass selection for traits identified by farmers. In some
generations,farmers did this in populations which were grown by breeders on land rented from a farmer. Soil fertility management
was lower than that normally used on the research-station. The breeding programme produced several varieties that have performed
well in research-station and on-farm trials. One of them, GDRM-187, has been officially released as GM-6 for cultivation in
hill areas of Gujarat state,India. It yielded 18% more than the local control in research-station trials, while being seven
days earlier to silk. In farmers' fields, where average yields were lower, the yield advantage was 28% and farmers perceived
GDRM-187 to have better grain quality than local landraces. PPB produced a variety that was earlier to mature than any of
those produced by conventional maize breeding, and took fewer years to do so. The returns from PPB,compared to conventional
breeding, are higher because it is cheaper and benefits to farmers are realised earlier.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
13.
Summary Improved crop varieties developed at experimental stations are intended for release for production in farmers' fields which are not necessarily the test sites. Therefore, it is important to measure the inter-site transferability of the crop variety. This study was undertaken to establish a statistical measure of inter-site transferability of a variety. Data on grain yield from two sets of multi-locational trials on barley and four sets of the wheat trials conducted by the Cereal Program, International Center for Agricultural Research in the Dry Areas, Syria, were analyzed to evaluate the inter-site transferability of the varieties. Genotype × environment interaction was significant and experimental errors were heterogeneous in each set of trials. Correlations between the slope (of linear regression of variety mean on location mean) and variety mean were significant (P < 0.01) in all trials. Correlations between the developed inter-site transferability statistic and the variety mean were significant (P < 0.05) in only two trials. Correlations between mean yield and probability of the inter-site transferability statistic were insignificant in all trials. The inter-site transferability statistic and the associated probability of the transferability may be used to select varieties which are high yielding as well as transferable to a new environment. The strong association of slope with mean yield restricted the scope of varietal selection but the introduced statistic did not suffer from this drawback. 相似文献
14.
利用A-PAGE研究谷子籽粒蛋白质多态性 总被引：3，自引：0，他引：3
研究谷子贮藏蛋白多态性对谷子品种选育和鉴定评价具有重要的意义。本文利用A-PAGE方法对来自不同生态区的24份谷子品种籽粒的水溶蛋白、盐溶蛋白、酸溶蛋白和醇溶蛋白的多态性进行了研究。结果发现,不同谷子品种之间籽粒水溶蛋白、酸溶蛋白谱带相似,基本没有差异;每个谷子品种的盐溶蛋白谱带有20多条,仅有4个品种出现多态性谱带,多态性也较低。说明谷子品种水溶蛋白、盐溶蛋白和酸溶蛋白A-PAGE谱带不适用于谷子鉴定研究。谷子醇溶蛋白谱带存在一定的异质性,每个品种有7~10条醇溶蛋白谱带,其中5条为公共条带,2~5条为多态性谱带,醇溶蛋白A-PAGE谱带可以作为谷子品种鉴定评价的依据。结果说明,和玉米、小麦等禾谷类作物相比,不同生态区谷子栽培品种蛋白质变异较小,遗传背景变化较小,因此需要不断丰富谷子品种的遗传基础,为谷子品种选育提供更加丰富的材料。 相似文献
15.
简述了世界各国的“日本枫树”垂枝型园艺品种资源概况。指出“日本枫树”是日本槭属植物所有种的泛称。品种选育起始于江户时代,距今已有300余年历史。现有品种数量估计在600个左右,其中垂枝型品种40余个,约占品种总数的7%。西方各国从19世纪20年代开始引种栽培,现有品种数量估计亦在600个左右,其中垂枝型品种90余个,约占品种总数的15.3%。园艺品种主要来自鸡爪枫(Acer palmatum Thunb.)、大红叶枫(Acer amoenum Carr.)、山红叶枫[Acer amoenum var. matsumurae (Koidz.) Makino]等种或变种,绝大多数为实生或枝变选育。“日本枫树”园艺品种广受世界各国爱好者青睐,垂枝型品种更加备受重视。提出了中国开发利用枫树资源途径方法的建议。 相似文献
16.
Multi-trait indices (MTI) weigh traits based on their importance to facilitate selection in plant and animal improvement. In animal breeding, economic values are used to develop MTIs. For vegetables, economic data valuing traits are rarely available. We posit that varieties with traits valued by growers and processors achieve higher market share and longer life span. Our objective was to develop MTIs predicting success of tomato varieties. Historical data for the California processing tomato industry from 1992 to 2013 provided measurements for yield, soluble solids (Brix), color, pH, market share, and life span for 258 varieties. We used random models to estimate best linear unbiased predictors (BLUPs) for phenotypic traits of each variety, and evaluated trends over time. Yield has been increasing from 2006, while Brix stayed constant. Because yield and Brix are negatively correlated, this trend suggests that Brix influenced selection. The average number of resistances reported in varieties ranking in the top ten increased from 2 to 4.5 between 1992 and 2013. MTIs predicting success from phenotypic traits were developed with general linear models and tested using leave-one-out cross validation. MTIs weighing yield, Brix, pH and color were significantly correlated to success metrics and selected a significantly higher proportion of successful varieties relative to random sampling. The index multiplying yield and brix, suggested in the literature, was not significantly correlated with variety success. The MTIs suggested that fruit quality had less of an influence on variety success than yield. The MTIs developed could help improve gain under selection for quality traits in addition to yield. 相似文献
17.
利用花生荚果图像特征识别品种与检验种子 总被引：1，自引：0，他引：1
为了验证以花生荚果图像特征识别品种和检验种子的可行性,选用代表北方大花生主推区的20份花生品种,从扫描图像获得花生荚果形态、颜色及纹理等50个特征,综合运用主分量分析(PCA)、神经网络(ANN)、支持向量机(SVM)、聚类分析等手段,讨论了品种识别、产地识别、DUS性状的选取和品种聚类过程,研究发现,经PCA优化特征的SVM识别模型识别效果好且识别结果稳定,20个品种的品种识别率达到90%以上。模型对3个不同产地的花生荚果正确识别率达到100%。另外从中筛选出一批对品种特异性、一致性和稳定性(DUS)测试有意义的备选特征,并建立了花生品种的谱系聚类树。研究结果对DUS性状的优选、花生品种及产地的识别及对花生谱系研究有一定参考价值。 相似文献
18.
[目的] 植物品种特异性(distinctness)、一致性(uniformity)和稳定性(stability) 测试(简称：DUS测试)是品种保护、品种审定、品种登记的必要条件。研制茄子(Solanum melongena L.)品种DUS测试指南旨在为测试和品种权实质审查工作提供科学依据。[方法]以《植物新品种特异性、一致性和稳定性测试指南 总则》(GB/T19557.1)为总体原则,以国际植物新品种保护联盟颁布的《植物新品种特异性、一致性和稳定性测试指南 茄子》(TG/117/4)为参考,通过对243份茄子品种的田间试验和多次同行专家修订,完成茄子的DUS测试指南(国家标准报批稿)。[结果]指南确定了42个测试性状及描述方法,筛选出20个标准品种,明确了茄子特判定、一致性和稳定性判定的原则。[结论]指南为我国茄子DUS测试的品种描述和特异性、一致性、稳定性判定提供了技术标准。笔者重点介绍了指南的编制原则和过程、测试性状的选择和标准品种的选用,以及特异性、一致性、稳定性的判定标准。 相似文献
19.