啮齿动物作用下退耕地山杏种子扩散与贮藏的季节变化

啮齿动物对植物种子的取食和扩散影响种子的时空分布,继而影响种子的萌发和幼苗建成,因而在森林更新中起着重要作用.在国有济源市愚公林场,选择退耕地生境,于春季、夏季、秋季分别释放人工标记的山杏种子,观察啮齿动物扩散与埋藏山杏种子的季节性差异.结果表明：1）退耕地中的啮齿动物主要包括大林姬鼠、社鼠、黑线姬鼠;2）山杏种子扩散速率在春季显著慢于夏季,夏季显著慢于秋季;3）种子搬运量受季节和种子状态交互作用影响,春季显著少于夏季,夏季显著少于秋季;4）不同季节种子平均搬运距离不同,秋季不同状态种子的搬运距离均大于春季和夏季;5）啮齿动物对山杏种子的贮藏点大小多为1粒种子,少量为2、3粒种子,且贮藏点大小与季节间存在显著的交互作用,春季单粒种子的贮藏点数量显著少于夏季和秋季,而夏季与秋季的贮藏点则倾向于多粒种子;6）在夏季和秋季各有5枚（共释放1800枚）被啮齿动物分散贮藏的山杏种子建成幼苗.     

53个猕猴桃品种(品系)亲缘关系的SCoT分析

现有主流猕猴桃品种的遗传背景相对单一,亲本来源地理分布狭窄,亲缘关系不清晰.为充分利用杂种优势,该研究以广西植物研究所猕猴桃种质资源圃收集的53个猕猴桃品种(品系)叶片为材料,使用SCoT分子标记进行遗传多样性分析.结果表明:(1)10条引物在53份猕猴桃供试材料中共扩增出110条条带,各引物扩增的条带在8～15条之间...     

Centennial olive trees as a reservoir of genetic diversity

Background and Aims

Genetic characterization and phylogenetic analysis of the oldest trees could be a powerful tool both for germplasm collection and for understanding the earliest origins of clonally propagated fruit crops. The olive tree (Olea europaea L.) is a suitable model to study the origin of cultivars due to its long lifespan, resulting in the existence of both centennial and millennial trees across the Mediterranean Basin.

Methods

The genetic identity and diversity as well as the phylogenetic relationships among the oldest wild and cultivated olives of southern Spain were evaluated by analysing simple sequence repeat markers. Samples from both the canopy and the roots of each tree were analysed to distinguish which trees were self-rooted and which were grafted. The ancient olives were also put into chronological order to infer the antiquity of traditional olive cultivars.

Key Results

Only 9·6 % out of 104 a priori cultivated ancient genotypes matched current olive cultivars. The percentage of unidentified genotypes was higher among the oldest olives, which could be because they belong to ancient unknown cultivars or because of possible intra-cultivar variability. Comparing the observed patterns of genetic variation made it possible to distinguish which trees were grafted onto putative wild olives.

Conclusions

This study of ancient olives has been fruitful both for germplasm collection and for enlarging our knowledge about olive domestication. The findings suggest that grafting pre-existing wild olives with olive cultivars was linked to the beginnings of olive growing. Additionally, the low number of genotypes identified in current cultivars points out that the ancient olives from southern Spain constitute a priceless reservoir of genetic diversity.     

Lectin in five soybean cultivars previously considered to be lectin-negative

Hemagglutinating proteins were isolated by affinity chromatography from seeds of each of five cultivars of soybeans (Clycine max (L.) Merr.) previously reported to lack detectable lectin (S.P. Pull et al., 1978; Science 200, 1277). Quantities were between 1,000 and 10,000 times less than that found in the seeds of the reference cultivar, Chippewa. The sensitivity of the hemagglutinating assay was 0.05 g ml^-1. Hemagglutinating activity was demonstrated in affinity-purified fractions from bulk seeds and seeds from individual plants in two cultivars, 30–70% ammonium-sulfate-precipitable fractions of seeds from individual plants of all five cultivars, and in whole crude extracts of individual seeds from each cultivar. In all instances, hemagglutinating activity was inhibited by galactose, anti-soybean agglutinin (SBA), and lectin-binding polysaccharide produced by Rhizobium japonicum. Affinity-purified lectin from seeds of a single Columbia plant was labeled with fluorescein isothiocyanate (FITC) and observed by fluorescence microscopy to bind to R. japonicum cells with specificity, intensity and localization indistinguishable from FITC-SBA. Lectins from distinguishable from FITC-SBA. Lectins from three cultivars in sufficiently high concentration for study had molecular properties very similar to Chippewa SBA.Abbreviations FITC fluorescein isothiocyanate - IgG immunoglobulin G - SBA soybean agglutinin     

小麦大面积种植品种与骨干亲本的遗传差异解析

为了解小麦大面积种植品种和育种骨干亲本的遗传差异特点,利用分布于小麦全基因组的428个SSR标记对4个大面积种植品种和4个骨干亲本进行了比较分析。结果表明,8个材料间的遗传距离变异范围为0.460~1.126,平均0.876,其中骨干亲本间的平均遗传距离(0.955)高于大面积种植品种(0.718)。骨干亲本中检测到的等位变异数较大面积种植品种高16.4%,前者的平均等位变异(2.90)也略高于后者(2.43)。从不同基因组和染色体来看,骨干亲本在A、B和D基因组上及19对染色体(除了2D和6D)的平均等位变异均高于大面积种植品种。以上分析表明骨干亲本的遗传异质性高于大面积种植品种。进一步比较二者的分子差异,发现骨干亲本中有518个特有等位变异(在大面积品种中没有出现),其中Xwmc513和Xbarc59为骨干亲本共有位点,大面积品种中也检测到315个特有等位变异,其中Xp3029、Xwmc235、Xgwm518、Xgdm43、Xbarc146和Xcfd80为共有位点。前人研究表明骨干亲本的一些染色体区段传递给了大面积种植品种,在它们的形成中发挥了重要作用。本研究发现的特异位点可能是遗传研究中除了骨干亲本重要位点之外的一些需要重点关注的基因组区域,进一步研究有助于解析一个品种是被大面积推广利用或成为骨干亲本的形成原因。     

设施黄瓜育成品种果实外观品质的遗传多样性分析

对我国新育成的不同生态类型的138个设施黄瓜品种的19个果实外观性状进行了调查分析,研究其遗传多样性。结果表明,参试品种质量性状的遗传多样性指数都小于数量性状,不同生态类型黄瓜品种果实外观性状的遗传多样性指数为华北型(1.33)>华南型(1.25)>欧洲温室型(1.0)。质量性状的遗传多样性指数为华南型(0.91)>华北型(0.65)>欧洲温室型(0.48);数量性状的遗传多样性指数为华北型(1.94)>华南型(1.56)>欧洲温室型(1.47)。华南型品种果实数量性状的变异系数均高于华北型和欧洲温室型品种。主坐标轴分析(PCO)将所有种质划分为3个区组,即1区为华北型种质优势区、2区为华北型华南型和欧洲温室型种质混合分布区、3区为华南型种质区。PCO结果表明,1区和2区发生了基因渗透。对交流区域中华北型品种自交分离,后代中出现的稀刺瘤和光皮种质的情况进一步验证了基因渗透的结果。参照育成品种的果实性状信息对黄瓜以后的育种工作提出了建议。     

Physiological parameters of salt tolerance during germination and seedling growth of Sorghum bicolor cultivars of the same subtropical origin

Salt-tolerant ecotypes (or cultivars, varieties, etc.) of different plant species have been long known to evolve in nature. In the past few years, plant breeders have made significant achievements regarding salt tolerance in a number of potential crops using artificial selection. The aim of this work was to evaluate and screening of the natural sea water (Red sea) tolerance of 7 Saudi local (Baish, Jazan; 17.388086, 42.524070) cultivars of sorghum (Sorghumbicolor L., Moench; Poaceae) with respect to the performance of some physiological parameters such as germination, shoot and root development which could be recommended to local farmers and plant breeders. The shoot growth of the studied sorghum cultivars were significantly affected by the exposure to sea water. Root growth was different among cultivars even when treated with normal water. The cultivar C3 (mix white and red seeds) was observed as more salt tolerant and cultivar C4 (whitish seeds) was more salt sensitive on the basis of the germination-ability and shoot development. Cultivar C3 was also observed to produce better seeds compared with the other cultivars. Results of this experiment can be useful to the local sorghum growing farmers or as a genetic resource for the development of sorghum cultivars with improved germination under salt stress.     

百合品种间的数量分类研究

根据 4 8个形态学性状 ,应用聚类分析将 9个不同来源的百合品种分为 3个类群 :亚洲系、东方系和麝香系。并显示了东方系和麝香系亲缘关系较近 ,符合北美百合协会对百合品种的分类与百合的育种历史、演化关系。文中将 4 8个形态学性状数据集划分为营养器官性状与生殖器官性状两个数据子集。单独采用营养器官性状子集进行聚类分析时 ,出现较大的差异 ,而对生殖器官性状子集的分析结果较为合理     

休眠期间低温累积对杏枝芽生理生化的影响

实验以３个不同低温需求量的杏品种为材料,在休眠时期进行１１种生理生化指标的测定,结果表明,随着低温累积量的增加,枝条与花芽总含水量、自由水含量,呼吸强度逐渐下降,萌芽前回升,束缚水、束／自比值、可溶性糖、可溶性蛋白质含量逐渐增加,到萌芽前减少,游离氨基酸与脯氨酸含量以及ＳＯＤ活性在完成低温需求量时最高,然后逐渐下降,游离氨基酸、脯氨酸含量与低温需求量存在着相关关系,相关系数为ｒ低需,游离＝０．９８     

Relationship between Cell Wall Susceptibility to Cellulases and Pectinases of Fusarium oxysporum and Susceptibility of Date Palm Cultivars

Fusarium oxysporum f. sp. albedinis, the bayoud disease agent of date palm, grows on a mineral medium containing the cell walls of date palm roots as a sole carbohydrate source. The growth and development of pathogen under these conditions was related to the production of extracellular cell wall-degrading enzymes (CWDE): cellulases, polygalacturonases, polygalacturonate transeliminases, and pectinmethylesterases. The mycelial growth and the sporulation of pathogen were higher in the presence of cell walls of susceptible cultivars (BFG, JHL, BSK) than in the presence of those of resistant cultivars (IKL, SLY, BSTN). After 8 d of fungal culture, the activity of CWDE was equal whatever is the origin of the cell walls (resistant or susceptible cultivars). After 16 d of culture, the activity of these CWDE was higher when the parasite was cultivated on the cell walls of the susceptible cultivars than on those of the resistant cultivars. A positive correlation was observed between CWDE activities and the growth and the sporulation of F. oxysporum after 16 d of culture. These results clearly show a relation between the susceptibility/resistance of the cell walls of the roots of the date palm to the parasitic CWDE and the susceptibility/resistance of the cultivars.