排序方式: 共有30条查询结果,搜索用时 46 毫秒
1.
2.
3.
为对棉花品种进行特异性鉴别,利用SSR(simple sequence repeats)方法对参加国家区试的2个棉花品种(A1、A2)的遗传特异性进行了研究。同时,根据棉花植物新品种DUS(distinctness,uniformity and stability)测试指南,对上述2份材料进行了20个农艺性状的特异性分析。结果表明,2个棉花品种的指纹图谱相同且田间性状相似,是同一个品种。该方法弥补了以往只考虑利用SSR鉴定品种的特异性而没有考虑田间农艺性状鉴定与SSR鉴定差异的不足,可以更客观地反映品种的特异性。 相似文献
4.
5.
根据植物新品种特异性、一致性和稳定性(DUS)测试的原理和技术,阐述了披碱草属植物新品种DUS测试指南的研制方法、性状选择与确定、标准品种的选用和判定标准等内容。按照UPOV《TG/1/3植物新品种特异性、一致性、稳定性测试及统一描述总则》、《中国饲用植物志》等资料,结合试验中披碱草属植物品种的生长特性,编写完成了《披碱草属DUS测试指南》。筛选出26个测试性状和10个标准品种;其中,质量性状2个、数量性状20个、假质量性状4个,为我国披碱草属植物新品种评价提供了DUS测试依据。 相似文献
6.
Variability in biodiversity is often assessed based on species richness, and this adherence to a single index has been typical
in studies of ecology, biogeography, and conservation in the past two decades. More recent studies have suggested that species
richness alone is insufficient as a measure of biodiversity, mainly because it is not necessarily correlated with other measures
of biodiversity. We examined (1) if nine indices embracing species diversity, functional diversity, and taxonomic distinctness
of stream macroinvertebrate assemblages show congruent patterns, and (2) if these indices show similar relationships to landscape
characteristics. Not all indices varied similarly and were thus not significantly correlated. There were three principal components
that effectively described variation in the correlation structure of the nine indices. These three components were: (1) diversity
and evenness indices, (2) two indices of taxonomic distinctness, and (3) species richness and functional richness. Four of
the nine biodiversity indices examined showed no significant relationships to landscape-catchment characteristics, and even
the significant correlations between the remaining five indices and explanatory variables were rather weak. However, species
richness showed a rather strong quadratic relationship to catchment area. Our study provided a number of suggestions for future
biodiversity studies at the landscape scale. First, given that different indices describe different components of biodiversity
and are not strongly correlated, multiple indices should be considered in any study describing stream biodiversity. Second,
despite the study was restricted to near-pristine streams, all indices showed considerable variation. Thus, this natural variability
should be accounted for prior to the examination of anthropogenic effects on stream biodiversity. Third, landscape-catchment
variables may have only limited value in explaining variability in biodiversity indices, at least in regions with no strong
anthropogenic gradients in land-use. 相似文献
7.
8.
百合品种一致性、稳定性与特异性的研究 总被引:9,自引:0,他引:9
对北京、西安、柞水、昆明四地的22个百合品种(种、变种)的11个间断型二态性状、55个间断型多态性状和19个连续型性状进行了观测,并进行了一致性、稳定性和特异性的分析.结果表明,各品种的间断型二态性状和大部分品种的间断型多态性状的一致性均较好,而连续型性状的一致性受环境影响显著.各品种间断型二态性状的稳定性相对较好,间断型多态性状较差,连续型性状变异最大.经一致性、稳定性分析,筛选出了34个间断型性状,用于品种特异性的判定,可将供试品种正确、有效地区别建议在进行品种测试时,尽量减少连续型性状的数量,并在温室栽培. 相似文献
9.
水稻新品种DUS测试数量性状特异性统计分析判别研究 总被引:3,自引:0,他引:3
对3个申请品种与其近似品种的10个主要数量性状连续2年的测试数据进行统计分析,结果表明:申请品种与其近似品种在指南中处于不同分级范围的数量性状,如果该性状均值相差相对较小,可能实际没有差异;申请品种与其近似品种在指南中处于同一个分级范围的数量性状,如果该性状均值相差相对较大,有可能存在显著差异;数量性状特异性统计分析判别是除指南判别以外的重要判别依据. 相似文献
10.
鸭茅系世界著名多年生冷季型优质牧草,在我国草地畜牧业发展和生态建设中起着重要作用。为系统地探明我国鸭茅品种(系)在表型水平上的多态性及变异规律,本研究对我国鸭茅8个品种和1个新品系单株的物候期、抗锈病能力、越夏率、生长速度、鲜干草产量、鲜干草茎叶比、鲜干比、分蘖数、植物学表型性状及DUS性状进行了系统研究,结果表明,1)各鸭茅品种(系)生育期、抗锈病能力、越夏率、生长速度、生产性能差异明显,以‘02-116’新品系表现较为突出;2)供试12个表型性状在品种(系)间差异均达到极显著(P<0.01)水平,变异系数变幅为21.64%(倒二叶长度)~106.20%(穗叶距),穗叶距、株高、茎上部节间长度、倒二叶宽度、株幅等性状与鸭茅产量显著相关;3)主成分分析表明前4个主成分因子累计贡献率达68.225%,鸭茅植株株型的形成和生长速度的动态变化,在很大程度上由叶片长度、叶片宽度、株高、穗叶距等共同决定;4)各品种(系)在7个供试DUS性状上均表现出不同程度的群体差异;5)品系‘02-116’与品种‘川东’、‘古蔺’等在主要形态上存在一定差异。 相似文献