基于SSR标记的云南地方稻种群体内遗传多样性分析

 用20对SSR引物对原产于云南的16份地方稻种和2份选育品种进行单个品种群体内的遗传多样性分析。结果表明,87.5%的地方品种群体内SSR多态性高于选育品种,而12.5%的地方品种群体内SSR标记多态性与选育品种相近。81.2%的地方稻种群体内的等位基因数(Na)和Nei基因遗传多样性指数(He)高于选育品种,而18.8%的地方品种群体内Na和He与选育品种相同或略小。水稻地方稻种群体内He的差异较大,其变异范围为0.0146～0.5117,其中,黄板所 1（1980年收集）、黄板所 2（2007年收集）、麻线谷 1（1980年收集）、麻线谷 2（2007年收集）的群体内遗传多样性较高,分别为0.2327、0.4214、0.5117和0.4489。87.5%地方品种的杂合度(Ho)明显高于选育品种;地方品种群体间遗传多样性差异很大,其中1/4的遗传差异来源于地方稻种群体内,差异极显著。RM333、RM257和RM180在供试云南地方稻种群体内的多态性、等位基因数、多样性指数和变异百分率均较高,适用于云南地方稻种群体内遗传多样性检测。     

西南高原生态区玉米地方品种抗病性鉴定

为明确西南高原生态区玉米地方品种的抗病性,采用人工接种的方法,对90份玉米地方品种进行大斑病、小斑病和锈病的抗病性鉴定。结果表明,参试品种中具有丰富的抗病资源,高抗锈病的有5份,高抗小斑病的有13份,抗大斑病的有26份,兼抗(含高抗、抗和中抗)3种病害的有32份。可见,西南玉米地方品种有大量抗病种质资源,值得进一步改良利用。     

Phenotypic diversity analysis of grain yield and yellow pigment content in germplasm collected from Iranian durum wheat (Triticum turgidum L.) landraces

This study was undertaken to compare patterns of agronomic characters and yellow pigment content diversity between Iranian durum landraces and modern varieties. In four field experiments, a collection of 127 accessions of landraces and 23 modern cultivars tetraploid wheat representing Iranian and global genetic diversity were tested under optimum and rain-fed conditions. Across the environments, the yellow pigment concentrations ranged from 1.85 mg kg^?1 to 8.95 mg kg^?1 in the field-grown samples. Multivariate analysis detected five groups, four including landraces and one comprising modern cultivars. As a group, modern cultivars were the most productive and showed high mean values for harvest index, grains per spike and yellow pigment, but they had the lowest plant height. Landraces had the highest mean number of spikes per m² and 1000-kernel weight, but were characterized by low plant height and yellow pigment content. Clustering analysis also showed that, based on yield and yellow pigment content, the accessions in different groups were of different origins, suggesting that there was no clear relationship between accessions and geographical diversity. According to our results, Iranian landraces can be particularly useful as germplasm in breeding programmes to improve spikes per m² and 1000-kernel weights.     

Collection and conservation of ‘Morado de Huetor’ Spanish tetraploid asparagus landrace

A cultivated tetraploid asparagus landrace ‘Morado de Huetor’ growing in the South of Spain has been collected and conserved ex situ in two experimental plots. This landrace has been reported to have an interspecific hybrid origin (A. officinalis × A. maritimus). A 59% of the total farmer plots cultivated in the region were visited and ripe fruits collected from 10 female plants per plot. Fruits from a total of 300 plants were collected and two half sibs descendents from each one were sown separate in two plots. Of the 88 farmer plots visited, the landrace was growing only in 34, in the rest the crop had been removed. Hence, ‘Morado de Huetor’ is in a very high risk of disappearing. Now this landrace is conserved ex situ in two experimental plots with sufficient number of plants to represent their maximum variability in order to be used in plant breeding.     

Morphological and Molecular Characterization of Novel Salt-Tolerant Rice Germplasms from the Philippines and Bangladesh

To screen for new sources of salinity tolerance, 688 traditional rice varieties from the Philippines and Bangladesh were obtained, and their tolerance to hypersaline conditions at the seedling stage was examined. A total of 29 Philippine lines and 15 Bangladeshi lines were scored as salt-tolerant.Morphological assessment(plant height, biomass and Na-K ratio) revealed that among the 44 salt-tolerant accessions, Casibon, Kalagnon and Ikogan had significantly higher relative shoot length difference, relative shoot growth reduction and shoot Na-K ratio than the tolerant check FL478.Additionally, AC and Akundo exhibited significantly higher Na-K ratios than the other genotypes. The genetic diversity of the 44 genotypes was assessed using 34 simple sequence repeat markers. A total of 133 alleles were detected across all loci. Cluster analysis showed that AC, Akundo and Kuplod were clustered along with FL478, indicating a strong genetic relatedness between these genotypes. IR29(susceptible check) was singly separated. The haplotype analysis revealed that none of the 44 genotypes had a similar allele combination as FL478. These accessions are of interest since each genotype might be different from the classical salinity-tolerant Pokkali.     

104个小麦品种抗条锈性及遗传多样性分析

为探究不同小麦品种(73个农家品种和31个育成品种)的抗条锈性和遗传多样性,在苗期对小麦品种接种条锈菌生理小种CYR32和CYR34进行抗性鉴定,并利用SSR分子标记技术进行遗传多样性分析。结果表明,在苗期抗性鉴定中,对于生理小种CYR32,有5个农家品种白大头、红洋辣子、老兰麦、红剑条和竹叶青(白)以及2个育成品种品冬904054-6和品冬904024表现近免疫;对于生理小种CYR34,有2个农家品种白芒麦和老兰麦以及2个育成品种品冬904024和晋79K214表现近免疫;对比农家品种与育成品种的抗性鉴定结果,发现对于生理小种CYR32,农家品种的抗性水平明显高于育成品种,而对于生理小种CYR34,育成品种的抗性水平高于农家品种。在遗传多样性分析中,104个品种的遗传相似系数变异范围在0.32~0.98之间,平均为0.65,但小麦品种遗传相似系数在来源地之间无明显差异。通过聚类分析发现,农家品种亲缘关系与来源地相关性较低,而育成品种的亲缘关系与来源地存在一定的相关性。因此,在品种改良过程中应引用不同类群的优质亲本,拓宽小麦育种的遗传基础,充分利用优质野生资源,适当搭配,选育更多小麦优良品种。     

河南省部分玉米地方品种主要产量性状的配合力分析

基于表型和基因型的聚类分析,从不同类群中筛选到18份河南省特异玉米地方品种,对其进行产量相关性状的配合力分析。结果表明,地方品种一般配合力对其产量性状作用较大,一般配合力(GCA)较高的是老人牙、红胡玉和朝鲜白马牙,其效应分别为29.93、13.65和9.94;产量的特殊配合力(SCA)较高的分别是黄早四×本地白玉米、掖478×白盖玉米、黄早四×老人牙、掖478×踏坑白、黄早四×混选一号和黄早四×红胡玉,其效应分别为15.62、14.36、13.03、12.88、9.33和8.59。在所有杂交组合中,黄早四×老人牙的产量最高,而掖478×踏坑白和掖478×白盖玉米组合次之,其平均单株产量分别为182g、170g和168g,这3个组合可作为潜势组合进一步试验。因此,在从地方品种中选育自交系作亲本时,应重点选择一般配合力高的地方品种,同时,结合特殊配合力测定,才能得到产量优异玉米杂交组合。     

利用SSR分子标记检测杂交籼稻和黄壳糯混合间栽模式下的基因流

 为了明确传统水稻品种和杂交稻长期混合间栽种植基因流是否会对传统水稻品种的种质产生影响,利用SSR分子标记对杂交籼稻冈优827,中优7号分别与黄壳糯按照8∶1混合间栽组合中基因流的发生情况进行了研究。结果显示, 在两个组合的每个品种所检测的3000个单株中均没有检测到基因流的发生。这一结果表明,现行的水稻品种多样性混合间栽模式中基因流不会对传统水稻品种产生影响     

贵州省花生地方品种的遗传多样性

为进一步了解贵州花生地方品种的遗传多样性,合理、高效利用花生资源,用50对SSR引物评价了贵州不同地理来源的68份花生地方品种,结果多态性较好的41对引物共扩增出79个等位基因,平均每个引物1.93个;多态性信息量(PIC)变幅为0.045(PM43)~0.951(PM169);Shannon信息指数变幅为0.2518(PM79)~0.6926(PM188),平均0.5268;Nei遗传多样性指数变幅为0.1699(PM79)~0.4995(PM188),平均0.3556。采用类平均法对欧氏距离聚类分析表明,在遗传距离为0.94时将68个花生地方品种分成2个大类,同一地理来源、同一粒型的地方品种的亲缘关系并不是最近的,表明地方品种间亲缘关系与地理来源关系不大。说明贵州花生地方品种具有丰富遗传多样性。