Genetic diversity analysis and fingerprint construction of Elymus germplasm based on SCoT markers北大核心CSCD

In this study,SCoT molecular markers were used to analyze the genetic diversity and construct DNA fingerprints of three species of Elymus on the Qinghai-Tibet Plateau to provide a theoretical basis for identification of the different species in collection material. Among 80 SCoT primers, 22 primers were selected for PCR amplification,and a total of 290 bands were amplified,of which 254 were polymorphic with the percentage of polymorphic bands（PPB）of 87.59%. The average values of the Shannon diversity information index（I）,Nei’s gene diversity index （H）,the observed number of alleles （Na）,and an effective number of alleles （Ne） were 0.5411,0.3643,1.9856,and 1.6270,respectively. Cluster analysis results showed that the genetic similarity coefficient ranged from 0.50 to 0.80. At a genetic similarity coefficient of 0.53,46 collections could be divided into 2 groups,and the results of the principal coordinate analysis were consistent with those of cluster analysis. At the same time,the DNA fingerprints of 46 materials were constructed by using 4 SCoT primers. The SCoT molecular marker was suitable for genetic diversity analysis and DNA fingerprint construction of Elymus germplasm resources. This study provides fundamental information for germplasm identification,high-quality character mining,and breeding practice for wild Elymus. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved.     

Response of grain yield and related agronomic traits of oilseed flax to diversified cropping rotations北大核心CSCD

This research aimed to identify a suitable planting pattern for oilseed flax production in a dry-farming region. A long-term field experiment was started in 2012 with a 4-year crop rotation cycle,designed to measure the effects on flax crop performance of previous crop,and various patterns of flax planting interval within the four-year rotation,compared with continuous flax cropping. Crop parameters measured included plant height,stem diameter,dry matter accumulation and distribution,and the experiment included six different crop rotation patterns：Flax→flax →flax→flax［（F）FFF］;Flax→wheat→potato→flax［（F）WPF］;Flax→potato→flax→wheat［（F）PFW］;Flax→ flax→wheat→potato［（F）FWP］;Flax→wheat→flax→potato［（F）WFP］and flax→wheat→potato→wheat［（F）WPW］. Results for the ninth year showed significantly increased grain yield（29. 89%-109. 57%）in crop rotation treatments compared with continuous cropping of oilseed flax. The ranking of the six tested rotations for yield was：（F）WPW>（F）FWP>（F）WFP>（F）PFW>（F）WPF>（F）FFF. The grain yield of oilseed flax was significantly affected by previous crop,frequency and years interval of flax cropping and number of years of continuous flax cropping. Yield was increased by 54. 45%-59. 29% under wheat stubble and potato stubble compared with oilseed flax stubble,and increased by 30. 66% and 109. 57%,respectively,under 50% and 25% frequencies,compared with 100% frequency. The grain yield of oilseed flax under two-year continuous cropping was higher by 29. 89% than four-year continuous cropping,and increased with increase in years interval between flax crops. Correlation analysis identified a significantly positive correlation between oilseed flax grain yield and effective capsule number,branch number and 1000-seed weight. The effective capsule number,branch number and 1000-seed weight of oilseed flax under rotation treatment were increased by 35. 88%-108. 91%,15. 47%-46. 19% and 14. 61%-16. 34%,respectively（P<0. 05）,compared with continuous cropping. In addition,the high grain yield of oilseed flax was accompanied by an increase in plant height,stem diameter and dry matter accumulation and these increases were,respectively,5. 11%-42. 24%,2. 77%-39. 92% and 31. 25%-117. 89% under the rotation regimes,compared with continuous cropping. Reduction in the number of years of continuous cropping years,change of crop stubble,decreased flax planting frequency and increased of interval between flax crops also improved flax crop performance. In summary,crop rotation improved the vigor of oilseed flax,resulting in greater plant height and stem diameter,improved dry matter accumulation and distribution,leading to increased branch number,effective capsule number and 1000-seed weight,and increase in the crop yield of oilseed flax. The results indicated that a multiple-crop rotation pattern was an effective way to avoid the yield reduction caused by continuous cropping in oilseed flax. The rotation： Flax→wheat→potato→wheat performed best among those tested and can be recommended as an appropriate cropping rotation for oilseed flax production in the dry region of northwest China. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved.     

Effects of plateau pika on the relationship between plant species diversity and functional diversity in alpine meadow北大核心CSCD

The relationship between plant species diversity and functional diversity in grassland will change with environmental changes. The plateau pika （Ochotona curzoniae） has an effect on the hydrothermal process of alpine meadow in its nesting area. However,it is not clear whether the disturbance of plateau pika effects the relationship between plant species diversity and functional diversity in alpine meadow. A random stratified and paired design was used to select plots in Luqu county in Gansu Province,and Qilian and Gonghe Counties in Qinghai Province and a field survey was conducted to investigate the effects of plateau pika disturbance on the relationship between plant species diversity and functional diversity of the alpine meadow. It was found that plateau pika disturbance significantly increased the plant species richness index and the species diversity index but did not significantly affect the species evenness index. Plateau pika disturbance significantly increased plant functional richness index （P< 0.05） but had no significant effect on the plant functional evenness index or the functional divergence index. With plateau pika disturbance effects,the relationship between plant functional richness index and species richness index changed from a logarithmic function to a quadratic function,and the relationship between plant functional evenness index and species evenness index changed from non-significant to significantly positive. In addition, positive correlations between functional richness index and species richness index,and functional richness index and species diversity index were significantly decreased,as were negative correlations between functional divergence index and species richness index,and functional divergence index and species diversity index were significantly decreased. The findings of this study provide basic information for understanding the mechanism of species coexistence of plant communities under plateau pika disturbance and help understanding of how plant diversity effects in an alpine meadow ecosystem function under plateau pika disturbance. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved.     

川西北高原50份燕麦种质农艺性状遗传多样性分析及综合评价

为客观评价燕麦种质资源农艺性状的遗传多样性,本试验对50份国外引进燕麦种质资源的27个农艺性状进行了形态多样性指数分析,并对其中的16个数量性状进行相关性分析、聚类分析和主成分分析,结果表明:遗传多样性指数最高的是穗长 (H'=2.04),变异系数最大的是营养枝数(63.36%);鲜草产量与干草产量、株高、分蘖数等呈极显著正相关(P<0.01);聚类分析将50份燕麦种质资源分为4大类群,第Ⅰ类群为早熟种质,具有植株高大、单株鲜草产量高、茎节数和小穗多、茎秆粗壮等特点,可作为选育多目标性状的优良种质或材料;第Ⅱ类群为中晚熟种质,但有益性状不明显;第Ⅲ类群属于中熟种质,植株分蘖能力强,种子千粒重高,可作为选育高产分蘖能力强的优良亲本;第Ⅳ类群属于晚熟种质,植株茎秆粗壮,可作为选育抗倒品种的优良亲本。主成分分析将16个数量性状指标集中在累计贡献率达77.00%的5个主成分中:第一主成分与燕麦牧草产量密切相关;第二主成分载荷最高的是单株营养枝数;第三主成分载荷最高的是生殖枝数;第四和五主成分主要反映茎节数和株高。综上所述,川西北地区引进的50份国内外燕麦种质资源的遗传多样性丰富,综合评价表明,种质Golden Yellow、Lightning、Golden Rain Ⅱ、Bambull Ⅱ可以作为亲本以改良当地燕麦品种。     

无芒雀麦农艺性状遗传多样性研究

对无芒雀麦(Bromus inermis)132份材料进行农艺学性状遗传多样性分析.结果表明,不同来源的材料间存在很大遗传差异,表现出较高的遗传多样性.变异系数为9%～105%,变异系数大的农艺性状有茎叶比、花药长、圆锥花序第1节间长、单株鲜草产量、种子产量、小穗长、水分含量、干草产量、鲜草产量、小穗数等.主成分分析显...     

西北地区和尚头小麦遗传多样性及农艺性状的关联分析

为了解西北地区和尚头小麦种质资源的遗传特性及主要农艺性状特征,采用43份不同来源的和尚头小麦种质材料,在均匀分布于小麦21条染色体上的150个SSR(simple sequence repeats)位点上检测遗传多样性,同时对19个农艺性状在两个试验点进行表型鉴定,并采用GLM(general linear model)模型进行分子标记与表型性状的关联分析。结果表明,19个农艺性状中数量性状遗传多样性明显高于质量性状,除壳色外,其他性状之间均存在不同程度的相关性。利用45对具有多态性的SSR标记共检测出151个等位变异,各标记等位位点变化范围为2～6,平均为3.36个,PIC(polymorphism information content)值变异范围为0.044～0.771。群体遗传结构分析将43份材料划分为8个亚群。关联分析发现11个SSR标记与农艺性状显著关联,单个标记对表型变异的解释率为8.89%～24.74%,这些标记可为特色小麦分子标记辅助选择育种提供理论参考。     

基于遗传多样性评估燕麦品种的农艺性状

为客观评价燕麦种质资源重要农艺性状的遗传多样性,并为黑龙江地区燕麦新品种选育提供关键数据,对51份燕麦种质资源13个农艺性状进行了形态多样性指数分析,并对其中的9个数量性状进行了聚类分析和主成分分析。结果表明,各性状的遗传多样性指数均较大,遗传多样性指数最高的是主穗长(1.517),其次为株高(1.448)和主穗粒重(1.414),性状变异系数最大的是主穗小穗数(34.8%),其次为主穗粒重(33.1%)和单株分蘖数(27.4%);聚类分析将51份燕麦品种的9个数量性状分为4大类群,类群Ⅰ为有益性状不明显,为多目标性状育种的亲本材料,类群Ⅱ为选育矮秆育种目标亲本材料,类群Ⅲ为高杆、增加分蘖数育种目标亲本材料,类群Ⅳ为选育大粒型、多轮层数、多小穗数等育种目标亲本材料。主成分分析结果表明,前3个主成分对变异的累计贡献率为70.09%,第一主成分反映种子产量,第二主成反映单株分蘖数,第三主成分反映株高。     

30份苏丹草种质资源农艺性状的遗传多样性分析

对30份苏丹草(Sorghum sudanense)种质资源的19个性状进行了遗传多样性、主成分与聚类分析。结果表明,19个性状在不同材料之间表现出了不同程度的多样性,千粒重的广义遗传力最高,为90.93%,穗一级枝梗长、穗粒重、茎粗等7个性状的广义遗传力在40%~70%,其他的性状广义遗传力相对较低,都在30%以下;主成分分析表明,前3个主成分对变异的累计贡献率为84.32%,第1主成分反映产量,第2主成分反映生育期,第3主成分反映叶型;聚类分析将其划分为四大类群,类群Ⅰ为早熟、矮秆、细叶、短穗松散、多分蘖型,类群Ⅱ为晚熟、高秆、宽叶、短穗紧密、多分蘖型,类群Ⅲ为适熟、中秆、宽叶、长穗松散、中等分蘖型,类群Ⅳ为晚熟、高秆、宽叶、长穗松散、少分蘖型。     

拉萨18个引进燕麦品种主要农艺性状和营养成分的遗传多样性分析

为了解在拉萨地区引种的18个燕麦(Avena satica)品种的遗传多样性,对18个农艺性状指标进行了多样性指数分析、聚类分析和主成分分析。结果表明:18个性状的遗传多样性指数范围在1.458~2.054,平均为1.87,遗传多样性丰富,同一性状间差异化大,各性状变异系数大,其中较高的是干草产量(52.354%)、旗叶长(51.946%)。聚类分析将18个燕麦品种分为4类,类群Ⅰ包括11个品种,属于高秆类群。类群Ⅱ包括1个品种,属于高干草产量类群。类型Ⅲ包括2个品种,属高营养、多籽粒型类群。类群Ⅳ包括4个品种,此类群在各个指标中均有较好的表现,是适宜在拉萨地区种植的燕麦品种。主成分分析共提取5个主成分,累计方差贡献率为79.592%,第一因子反映叶产量和种子产量,第二因子反映酸性洗涤纤维和中性洗涤纤维,第三因子反映粗灰分,第四因子反映茎叶比和粗蛋白。第五因子反映株高。通过构建5个主成分为参数的综合评价模型,计算综合得分,可以筛选出贝勒Ⅱ、牧王、海威为适宜在拉萨地区种植的燕麦品种。     

野生及栽培苜蓿种质资源遗传多样性的同工酶分析

采用过氧化物酶、淀粉酶、过氧化氢酶电泳技术,对两份野生紫花苜蓿(Medicago sativa)种质资源和27份栽培苜蓿品种的遗传多样性进行分析。结果显示,3种同工酶共检测到30条稳定酶带,其中6条为特异酶带,出现在陇东野生紫花苜蓿、拜城野生紫花苜蓿、兰杰兰德和大西洋紫花苜蓿酶谱中。过氧化物酶、过氧化氢酶和淀粉酶的多态位点百分率分别为75.00%、55.56%和33.33%。29份苜蓿材料间的相似系数介于0.633～1.000,平均值为0.867,两份野生紫花苜蓿种质资源与栽培品种间的相似系数相对较小,栽培品种间的相似系数相对较大。聚类分析表明,在相似系数0.772处可将29份苜蓿材料聚为3类,第1和第2类分别由陇东野生紫花苜蓿和拜城野生紫花苜蓿单独组成。陇东野生紫花苜蓿和拜城野生紫花苜蓿在主成分分析图中的位置也相对孤立,表现出野生种质资源与栽培品种间较远的亲缘关系。     

红三叶种质资源农艺性状的综合评价及聚类分析

通过变异系数、相关性分析和聚类分析对引进的20份红三叶种质资源进行农艺性状多样性分析。结果表明:各个性状在红三叶居群内具有较大程度的变异,其中,顶生小叶大小变异系数最大,为26.16%。各个性状间均有一定相关性,顶生小叶长度与宽度呈显著正相关,与大小呈极显著正相关,顶生小叶宽度与大小呈极显著正相关。聚类分析表明,20份材料分为3大类群,第1类包括6个居群,其特点是茎长度、顶生小叶长度、小叶宽度、小叶大小和花序直径均高于其他2个居群;第2类包括13个居群,其特点是叶形指数较高;第3类包括1个居群,其特点是植株高大、茎粗,理论牧草产量高。     

西南地区白玉米地方种质资源分布及遗传多样性

通过表型性状结合的主成分分析,SSR标记分析和群体结构分析,对50个西南地区白玉米地方品种的种质资源分布及遗传多样性进行了研究。结果表明,白玉米地方品种农艺性状表现出很大差异,主成分聚类将其分为7个类群,大部分品种聚在一个群内,但也有少数品种单独成类;利用筛选出来的51对扩增条带清晰,具有明显多态性的SSR引物,共检测到 515个多态性位点,SSR位点的平均多态性位点数为10.1个,每个位点的等位基因数为 5~19个,平均为12个,多态信息量(PIC)分布范围为0.764～0.958,平均为0.885,遗传相似系数变幅在0.574～0.840,平均为0.684,标记索引指数(MI)分布范围为3.820～18.208,平均值为9.775。SSR分析将所选品种分为8类,且84%的组合集中在前三大类。从地方品种来源地分析来看,地理位置相似或接近的地方品种大多两两成类,遗传相似系数很高,而群体结构分析显示,白玉米地方品种的群体结构受其地理环境气候的影响。少数地方品种较独立,可以进一步从种质资源方面研究利用。