核糖体蛋白L41与黄曲霉抗性的关系

已知与编码核糖体蛋白L41 (RPL41)的CD399094相似的基因序列在黄曲霉敏感品种发育中种皮中上调表达.从花生黄曲霉抗性品种J11中克隆了相似基因.通过分析比较来自开放数据库中黄曲霉抗性和敏感品种花生发育中种子表达的RPL41序列,并对黄曲霉抗性和敏感品种果实不同发育时期和部位及叶片用荧光定量PCR做进一步的分...     

花生黄曲霉抗性与类受体蛋白激酶的相关性分析

LRR类受体激酶RH4基因在花生黄曲霉敏感品种发育种子的种皮中上调表达.基于这类受体激酶多由于序列的变异导致抗性的变异,笔者将数据库中花生抗黄曲霉和敏感品种相似基因编码的蛋白进行序列比较分析,发现抗性品种与敏感品种的类似蛋白序列有很大差别.用荧光定量PCR方法对抗性品种KB153与敏感品种JH1012发育中不同时期的果...     

利用核心种质发挥及评价花生抗黄曲霉资源

黄曲霉菌极大地限制全世界的花生生产和产业发展,且生产上抗性品种较少,我国花生育种和生产中的抗性资源缺乏,迫切需要发掘抗黄曲霉菌种质。本研究以中国花生核心种质561份和ICRISAT微核心种质155份,鉴定了黄曲霉侵染和产毒抗性,发掘出抗黄曲霉侵染和产毒种质各8份,包括具优良农艺性状的抗黄曲霉产毒种质51002-6。鉴定结果表明,ICRISAT花生微核心种质中抗黄曲霉侵染和产毒种质的频率高于中国花生核心种质;普通型花生资源中抗黄曲霉侵染种质的频率较高,龙生型资源中抗黄曲霉产毒种质的频率较高。根据SSR分析,鉴定出与生产上推广应用的优良品种中花5号、中花6号、中花12和远杂9102遗传距离较远的抗黄曲霉产毒种质ICG12625和抗侵染种质ICG4750,拓宽了我国花生品种改良的遗传基础。根据抗病基因产物的NBS类型保守域设计简并引物对抗黄曲霉种质的DNA进行PCR扩增、克隆、测序和分析,获得了1条RGA片段。     

花生4种重要病害抗性育种研究进展

花生是中国重要的油料作物、经济作物和食用作物,叶斑病、锈病、青枯病和黄曲霉病是花生生产上的4种重要病害,严重制约着中国花生产业的发展。本研究对这4种重要病害发生和危害、抗性资源筛选鉴定和遗传改良、抗性基因挖掘和应用等方面的最新研究进展进行总结,提出了这4种重要病害抗性育种中存在的问题：(1)抗性品种抗源狭窄;(2)抗性与不良性状连锁;(3)辅助育种分子标记缺乏,并展望了这4种重要病害的抗性育种的研究方向,以期为花生叶斑病、锈病、青枯病和黄曲霉病抗性育种提供参考。     

SSR标记与花生抗黄曲霉性状的关联分析

本文选用100对SSR引物对12个抗感黄曲霉花生品种的基因组DNA进行扩增,结果表明共有41对引物在不同品种间检测出2～4个等位基因,多态性信息量(PIC)为0.153～0.750.供试品种SSR标记基因型与黄曲霉侵染指数间的关联分析表明有5个标记与抗性相关,其中标记pPGSseq19D9与抗性关联度最高,Pearson相关系数达0.913.进一步观察发现pPGSseq19D9的扩增带型能直接区分抗感品种,初步推断pPGSseq19D9可能与一个贡献率较大的抗黄曲霉基因连锁.     

花生黄曲霉侵染抗性的AFLP标记

本研究利用抗、感黄曲霉菌侵染的花生品种为亲本配制杂交组合“J11×中花5号”,以其F₂分离群体为研究材料，采用AFLP技术和BSA分析方法，获得了与花生黄曲霉菌侵染抗性连锁的2个分子标记，标记与抗性间的遗传距离分别为8.8 cM和6.6 cM;利用获得的分子标记对抗、感黄曲霉的花生种质资源进行了分子鉴定，实验结果表明分子标记与抗性鉴定结果具有较高的一致性，证实了两标记应用于研究群体之外的育种潜力。该抗侵染分子标记的建立为开展花生抗黄曲霉辅助选择育种提供了有效的筛选技术。     

利用RIL群体创造抗黄曲霉兼抗青枯病的高油花生新种质

协同提高抗青枯病花生品种的黄曲霉抗性及含油量是我国花生育种的重要目标之一。利用远杂9102×中花5号杂交后代衍生的重组近交系群体(RIL),通过黄曲霉抗性、青枯病抗性鉴定及含油量测试,表明黄曲霉抗性受2对连锁并具累加作用主基因+加性多基因控制,含油量受2对具抑制作用主基因+加性多基因控制,RIL群体的黄曲霉抗性和含油量变异远远超过双亲的差异,表明它们均具有通过互补产生超亲性状的潜力。获得了抗黄曲霉或抗青枯病的高油后代家系18份,其中抗黄曲霉兼抗青枯病高油新种质1份(J091)。农艺性状和SSR分析结果表明,18份后代材料具丰富的遗传多样性,农艺性状优良,具有重要育种价值。     

花生种子白藜芦醇含量与黄曲霉产毒抗性的关系

选用抗黄曲霉产毒的花生品种(系)和高产毒品种(系), 采用强产毒菌株AF2202人工接种水分吸涨的花生种子, 培养7 d后,测定接种和未接种的花生种子中白藜芦醇及黄曲霉毒素含量,探讨白藜芦醇与花生种子黄曲霉产毒抗性之间的关系。结果表明,抗黄曲霉产毒花生品种(系)的白藜芦醇含量较高,平均为37.3 µg kg^–1,高产毒品种含量相对较低,平均为13.3 µg kg^–1,抗、感品种之间存在显著差异。吸胀处理后抗产毒花生品种(系)白藜芦醇含量提高2.0倍,感病品种(系)仅提高1.6倍,对不同品种(系)处理后的种子二次接种,令黄曲霉毒素含量下降37.6%~75.8%,但吸胀处理后抗产毒品种(系)的黄曲霉毒素含量仍低于感病品种(系)。相关分析表明,花生白藜芦醇含量与黄曲霉毒素含量呈显著负相关,并且在离体培养基中添加浓度大于3.0 μg mL^–1的白藜芦醇可导致黄曲霉菌产毒量大幅下降,说明白藜芦醇对黄曲霉产毒具有抑制作用。     

利用ZmPR1a基因表达量快速筛选玉米抗纹枯病品种资源

玉米纹枯病是玉米上的主要病害之一,种植抗性品种是最有效和最安全的纹枯病防治方法.为缩短抗纹枯病玉米品种的选育周期,本研究通过比较受侵染后抗病相关基因的表达差异,开发了一种玉米品种资源抗纹枯病快速鉴定的技术,可在2～3周内完成玉米抗纹枯病品种的鉴定.相对荧光定量PCR (RT-qPCR)结合田间抗性鉴定结果表明,抗性品种在接种后24 h内抗病相关基因ZmPR1a上调4倍以上,但易感品种未表现出相应趋势.通过比较玉米品种与对照品种接种后ZmPR1a的表达情况,可以快速鉴定玉米种质资源对纹枯病的抗性,有利于加快抗病育种.本研究还为玉米抗纹枯病机制研究提供了参考.     

农作物收获前黄曲霉毒素污染与控制措施

黄曲霉毒素(aflatoxin,AFT)是曲霉属真菌产生的一大类生物毒素,是危及食品安全和人类健康的主要物质之一。农产品收获前黄曲霉毒素污染是热带、亚热带地区普遍存在的问题,其中在玉米、花生、棉籽、辣椒籽和一些木本坚果及其产品中尤为严重。国内外现有研究结果表明,多种因素可影响作物收获前黄曲霉毒素污染,其中干旱和高温的综合胁迫是最主要的环境因素。作物抗性对降低毒素污染具有重要作用。综合运用分子生物学及常规育种技术改良作物品种对黄曲霉菌侵染或产毒的抗性以及对其他病虫害及干旱的抗(耐)性,是解决黄曲霉毒素污染问题的重要途径。作物生产过程中病虫害的防治和合理的田间管理是作物收获前黄曲霉毒素污染的有效防控措施。     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

Summary Cytoplasmic male sterility (cms) is described in the F₁ hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf ₁) and recessive for the other (Rf ₂).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph ₃(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf ₁(one of two dominant additive genes controlling early season leafing out) indicated that Rf ₁and Rf ₂were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf ₁, and 0.15 for Lf ₁-Sph ₃were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph ₃.It is suggested that competitive disadvantage of lf ₁-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph ₃. Poor performance of lf ₁- (and possibly lf ₂-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).     

Screening techniques and sources of resistance to parasitic angiosperms

Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.