二倍体与四倍体刺槐组培苗形态和生理性状比较     

李秀宇  董黎  孙宇涵  李健康  刘晓迪  谭红岩  Saleem Uddin  李云 《核农学报》2021,35(3):605-612

为了比较二倍体与四倍体刺槐组培苗不同无性系之间的差异,本研究分别测定二倍体刺槐组培苗和人工诱导四倍体刺槐组培苗的形态及生理指标,并进行相关分析。结果表明,多数四倍体刺槐无性系的长势、抗逆性优于二倍体;二倍体与四倍体刺槐不同无性系以及不同形态、生理指标之间存在丰富的变异,其中四倍体刺槐的变异更为丰富;各测定指标之间存在较为复杂的相关关系,在选择育种时,需综合考虑。根据试验结果,结合育种目标,可选育出优良四倍体刺槐无性系,丰富刺槐种质资源,增加遗传多样性。本研究为刺槐倍性育种工作提供了理论依据和科学参考。  相似文献   

Natural Homologous Triploidization and DNA Methylation in SARII-628, a Twin-seedling Line of Rice （Oryza sativa）     

PENG Hai ZHANG Hong-yu LI Yun XU Pei-zhou WANG Xu-dong WU Xian-jun 《水稻科学》2007,14(4):265-271

A total of five pairs of diploid-triploid twin-seedlings (a diploid seedling and a triploid seedling emerged from a grain) were selected out from 4500 pairs of seedlings from SARII-628, a twin-seedling rice line. SSR analysis indicated that no difference between the diploid seedling and corresponding triploid seedling in a twin-seedling was found at the 310 loci, indicating that there was no obvious change in DNA primary structure. A modified AFLP technique ‘MSAP (methylation-sensitive AFLP)’ was used to analyze methylation mutation. Although no methylation mutation was noted among the five diploids, 29 methylation mutation loci were found from the corresponding triploids. This suggested that methylation mutation happened rapidly on M0 generation after natural homologous triploidization. The mutations were classified into 10 types, including 3 increased types, 3 decreased types and 4 undecided types of methylation-degrees. The bands of 22 loci were sequenced and then those sequences were searched through website. The result showed that the methylation mutation involved into the whole rice genome and the 12 pairs of chromosomes. The mutation trend was site-related and there were different mutation loci for different triploids, which foretold that SARII-628 would have different evolution fates after natural homologous triploidization.  相似文献   

双胚苗水稻SARⅡ 628的自然同源三倍化和DNA甲基化     

彭海  张红宇  李云  徐培洲  汪旭东  吴先军 《中国水稻科学》2006,20(5):469-474

从4500对SARⅡ 628的双胚苗中筛选出5对二倍体 三倍体双胚苗。SSR分析显示它们在所检测的310个位点上没有差异。以AFLP为基础的MSAP（methylation sensitive AFLP）研究显示,5个二倍体在493个位点上甲基化状态没有差异。与二倍体比较,相应的三倍体虽然在甲基化总体水平上变化不大,但共有29个位点甲基化类型在不同单株上发生了变异,表明SARⅡ 628自然同源三倍化后甲基化变异在M0代就迅速发生。变异共有10种类型,包括甲基化程度上升、下降各3种类型以及不定类型4种。对其中22个位点测序检索显示：这些甲基化变异涉及整个水稻基因组的12对染色体且具有位点特异性,不同单株的变异位点各不相同,预示着SARⅡ 628不同单株在自然同源三倍化后将走向不同的命运。  相似文献   

Harvest management based on leaf stage of a tetraploid vs. a diploid cultivar of annual ryegrass          下载免费PDF全文

J. K. Q. Solomon  B. Macoon  D. J. Lang 《Grass and Forage Science》2017,72(4):743-756

Leaf stage‐dependent defoliation is linked to the plant's physiological status and may be a more suitable criterion than time‐based intervals for harvesting forage grasses, but no reports of research with annual ryegrass (Lolium multiflorum Lam. var. westerwoldicum) were found. To address this, a 2‐year field study was carried out at Raymond, MS, on a Loring silt loam soil (fine‐silty, mixed, thermic Typic Fragiudalfs). Forage production, morphological characteristics and nutritive value responses to defoliation based on leaf stage (2, 3 and 4 leaves per tiller) and two residual stubble heights (RSH; 5 and 10 cm) of a tetraploid (“Maximus”) vs. a diploid (“Marshall”) cultivar of annual ryegrass were quantified. Forage harvested, in 2011, increased linearly as leaf stage increased from 7.3 to 8.8 Mg/ha, but during 2012 was least (7.0 Mg/ha) at 3‐leaf stage and similar at the other two leaf stages (7.6 Mg/ha). Tiller density was less for Maximus (1,191 tillers/m²) than for Marshall (1,383 tillers/m²). Leaf blade proportion decreased with increasing leaf stage and was greater by 9% for Maximus than for Marshall. Generally, forage nutritive value became less desirable with increasing leaf stage. There was a dichotomy in forage harvested and nutritive value responses, but maximum forage productivity was achieved when annual ryegrass was defoliated at the 4‐leaf stage interval.  相似文献   

二倍体月季F_1群体的SSR鉴定与遗传分析     

周宁宁  李淑斌  李远波  蹇洪英  晏慧君  王其刚  陈敏  邱显钦  张颢  唐开学 《园艺学报》2017,44(1):151-160

以中国古老月季品种‘月月粉’(Rosa chinensis‘Old Blush’,用OB表示)为母本,‘无刺光叶蔷薇’(Rosa wichuriana‘Basye’s Thornless’,用W表示)为父本,构建F_1代共296个单株。从146对SSR标记中筛选出亲本间多态性好且条带清晰的23对SSR标记,对随机选择的94株F_1进行杂种鉴定和遗传分析。结果表明:筛选到3个纯合显性标记分别为Fv512、Fv609和305,可单独一次性鉴定全部杂种真实性;随机筛选的94株子代均为真杂种;20个SSR标记用于基因型分析,有9个标记出现了偏分离,并在统计上达到显著或极显著水平,偏分离率45%,说明该F_1群体基于SSR位点的基因型偏分离率较高,在进行高密度遗传图谱构建时应重视偏分离标记对作图的影响;UPGMA聚类分析显示,94株F_1的遗传变异大,且遗传多样性丰富,可划分为2个大类7个亚类。  相似文献   

野生二粒小麦与二倍体野燕麦远缘杂交后代的核型分析及进化关系     

郑会敏  冯海嫣  张素勤 《湖南农业大学学报(自然科学版)》2011,37(6):598-602

对野生二粒小麦与二倍体野燕麦远缘杂交后代进行染色体核型分析。结果表明：杂交后代084株系的核型公式为2n=6x=42=36m(4SAT)+6sm，核型为1A，为极对称核型，属于原始类型；野生二粒小麦、二倍体野燕麦及084株系的进化指数分别为1、4和1，表明084株系的进化程度与野生二粒小麦一致，低于二倍体野燕麦；084株系的染色体相对长度较亲本大，且其平均臂比、核型不对称系数及臂比大于1.7的染色体比例均在野生二粒小麦与二倍体野燕麦之间，说明远缘杂交在一定程度上对加速小麦属的进化有重要意义；084株系染色体臂比与母本的相近，且存在4对染色体与父本的相对长度和臂比极为相近，核型分析结果从一定程度上证明了野生二粒小麦与二倍体野燕麦杂交后代的真实性。  相似文献   

高温胁迫对二倍体和四倍体萝卜生长和膜伤害的影响   总被引：4，自引：0，他引：4  

徐伟钰  张蜀宁  张杰  张振超  侯喜林 《南京农业大学学报》2006,29(4):43-47

在田间试验条件下，比较了自然高温下二倍体和四倍体萝卜的生长情况、株型和产量，并在光照培养箱中研究了高温胁迫（36℃／26℃（昼／夜），10d）对膜的伤害。研究结果表明，四倍体萝卜的耐热性强于二倍体，四倍体表现出抗热特征：株型直立，叶片增厚，叶形缺刻少趋近板型叶，叶片深绿色且高产，与二倍体相比差异显著。在控制高温胁迫过程中，四倍体的电解质渗透率、可溶性糖和MDA含量均低于二倍体，但两者变化趋势相似；四倍体的SOD、POD和CAT活性，可溶性蛋白及总叶绿素含量均高于二倍体。因此，田间试验结合人工模拟高温可以很好地鉴定萝卜耐热性。  相似文献   

葡萄二倍体与四倍体品种间杂交胚挽救取样时期的确定   总被引：14，自引：0，他引：14  

徐海英  闫爱玲  张国军 《中国农业科学》2005,38(3):629-633

 通过系统测定葡萄二倍体与四倍体品种间杂交胚珠的重量变化和解剖观察胚珠的发育情况，判断其败育发生时期和发生方式，并进一步通过胚珠培养试验确定取样时期。与无核品种不同，大多数有核品种与倍性不同的品种杂交后，胚珠的败育存在个体间差异。胚珠发生败育的时期与母本品种的成熟期相关，早熟品种从花后第5周开始出现败育胚珠，中熟品种开始败育时期比早熟品种晚1周，晚熟品种花后9周才开始败育。胚挽救的取样时期可以根据母本品种成熟期确定，早熟品种为授粉后6～9周，中熟品种为授粉后7～10周，晚熟品种为授粉后9～12周。  相似文献   

Production of Spontaneous Diploid Lines from Isolated Microspores Following Cryopreservation in Spring Rapeseed (Brassica napus L.)   总被引：2，自引：0，他引：2  

J. L. Chen  W. D. Beversdorf 《Plant Breeding》1992,108(4):324-327

Cryopreservation of microspores provides a potentially powerful means for increasing percentage of spontaneous diploids in microspore-derived populations in rapeseed (Brassica napus L.). This study was to investigate the production of spontaneous diploid lines in relation to steps of cryopreserving micro-spores of two spring rapeseed breeding lines G-231 and M3-124. Microspores of both genotypes were isolated and subjected to Cryopreservation. The step of cooling process (before liquid nitrogen immersion) in a Cryopreservation protocol resulted in high percentages of spontaneous diploids in lines regenerated from frozen microspores in both genotypes. Liquid nitrogen immersion and subsequent thawing process had no influence on the percentage of spontaneous diploids. A linear relationship between percentage of spontaneous diploids and cooling temperatures was detected. The lowest cooling temperature of ?40 °C yielded the highest percentages of spontaneous diploids (51.1 % in G-231 and 47.7 % in M3-124, respectively), which were more than doubled in comparison to those in the corresponding unfrozen controls. The current study indicated that cold treatment may be utilized to greatly enhance the percentage of spontaneous diploids in rapeseed breeding programs.  相似文献   

Sugar beets homozygous for resistance to beet cyst nematode (Heterodera schachtii Schm.), developed from monosomic additions of Beta procumbens to B. vulgaris     

W. Heijbroek  A. J. Roelands  J. H. de Jong  C. van Hulst  A. H. L. Schoone  R. G. Munning 《Euphytica》1988,38(2):121-131

Summary Monosomic additions of Beta vulgaris x B. procumbens with resistance to beet cyst nematode (Heterodera schachtii Schm.) were used for the production of resistant diploids through incorporation of the B. procumbens chromosome fragment bearing the resistance gene(s) into one of the sugar beet chromosomes. The heterozygotes obtained accordingly were selfed for producing homozygotes. These homozygotes differed morphologically from commercial sugar beet varieties, but produced reasonable amounts of pollen. Female transmission of resistance was 100%, whereas male transmission, apart from some exceptions, was more than 90%. The number of hypersensitivity reactions to penetrated larvae was related to the degree of susceptibility. Larval development was severely retarded in the resistant plants, preventing most of them to produce cysts. If cysts were formed, their content was considerably less as compared to those in the susceptible plants.  相似文献