番茄品种对ToMV抗性与氧化酶活性的关系研究

测定了6个不同抗性番茄品种接种ToMV两周后POD、PPO和PAL活性,以及POD同工酶酶谱的变化。结果表明：抗、感病品种接种ToMV后POD、PPO和PAL活性均比相应未接种株高,而且POD、PPO和PAL的酶活增长率与抗病性成负相关;感病品种接种株的POD同工酶谱带数都比相应未接种株多出2条酶带,而抗病品种只增加了1条酶带。     

大豆种子萌发中过氧化物酶同工酶的动态研究

应用聚丙烯酰胺凝胶垂直平板电泳对浙春3号和浙春2号大豆种子萌发过程及幼苗生长中的过氧化物酶（POD）同工酶进行了研究。结果表明，浙春3号和浙春2号在种子萌发过程中随着时间的推进，两品种间POD同工酶谱带的差异逐渐增大，在萌发14d后2个品种间子叶POD同工酶酶谱的差异较为显著。2个品种的子叶，根，茎，叶POD同工酶酶谱之间也都表现出一定差异。     

大豆过氧化物酶同工酶分析

为了得到7个大豆品种的亲缘关系,对其叶、茎、根进行聚丙烯酰胺凝胶电泳(PAGE)处理,分析了过氧化物酶(POD)同工酶酶谱,其分离出30条酶带,POD在不同大豆各器官中分布具有特异性:综合同工酶谱和联合相似系数初步讨论了亲缘关系,结果认为,垦丰16与垦丰17为优势杂交组合,为作物品种鉴定、选育优势杂交亲本提供一定依据。     

果蔗不同器官在不同生育期的同工酶聚类相关分析

为了解过氧化物酶(POD)和酯酶(EST)同工酶在果蔗生长中的变化规律,本研究选择不同的取样时期和植株不同器官,对8个果蔗品种利用垂直平板聚丙烯酰胺电泳得出的叶片、根组织不同生育时期POD、EST同工酶酶谱进行聚类分析,并检测其相关性。结果表明：（1）不同品种间同工酶谱的遗传相似系数存在差异,特别是外引黑皮果蔗(Badila)与中国地方品种之间存在着一定的遗传差异;（2）不同生育时期叶片或根部的POD同工酶和EST同工酶酶谱的聚类图都存在着差异;（3）叶片中的POD、EST酶谱在各个生育时期均达到极显著相关。说明叶片是这两种酶基因表达的最重要活性部位,因此叶片可以作为同工酶分析较为稳定和适宜的采样部位。     

红芽芋低温疗法脱毒苗遗传稳定性同工酶检测

本研究对江西铅山红芽芋低温疗法脱毒苗的遗传稳定性进行同工酶检测。结果表明,SOD同工酶酶谱共有4条酶带,Rf分别为0.196、0.534、0.589和0.625,Af均为100%;POD同工酶酶谱共有7条酶带,Rf分别为0.018、0.053、0.228、0.263、0.316、0.351和0.632,Af均为100%;CAT同工酶酶谱只有1条酶带,Rf为0.145,Af为100%;SOD、POD和CAT同工酶的多态性百分率(P)均为0,有效等位基因数(Ne)均为1.000;SOD、POD和CAT同工酶酶谱带的遗传相似系数均为1.000,聚类分析显示低温疗法脱毒苗与大田苗均在同一组,表明低温疗法脱毒苗的遗传稳定性高,无遗传变异。本试验结果可为江西铅山红芽芋低温疗法脱毒苗的遗传稳定性提供一些同工酶方面的依据。     

琯溪蜜柚果实汁胞粒化过程中同工酶变化的研究

研究琯溪蜜柚果实粒化过程中过氧化物酶(POD)、超氧物岐化酶(SOD)、过氧化氢酶(CAT)同工酶的变化;通过授粉处理,以未授粉的自交果和授粉的杂交果的琯溪蜜柚果实汁胞为材料,采用垂直板聚丙烯酰胺凝胶电泳方法进行同工酶测定;琯溪蜜柚果实粒化过程中汁胞粒化指数随着果实成熟而上升,自交果汁胞粒化指数大于杂交果;自交果汁胞中出现的POD同工酶酶谱共分离出4条,SOD同工酶酶谱分离了6条,CAT同工酶酶谱有3条,相应的杂交果汁胞POD同工酶出现2条谱带、SOD同工酶显示4条谱带,过氧化氢酶同工酶没有观察到谱带;与琯溪蜜柚汁胞粒化关系密切的同工酶为POD、SOD同工酶。     

四棱豆过氧化物酶同工酶的研究

为了阐明过氧化物酶（POD）同工酶在四棱豆中的分布规律，鉴定不同四棱豆品种间的亲缘关系，选育优势杂交亲本，我们采用聚丙烯酰胺凝胶垂直板电泳技术，研究了同一株四棱豆（K0027）不同节位成熟叶片和16个品种的POD同工酶酶谱特征。结果表明：POD同工酶在同一株四棱豆9个不同节位成熟叶片中的酶带数均为10条，并且各酶带相应的Rf值基本相同；而在16个不同四棱豆品种中酶带数为6~11条，并且各酶带的宽窄、颜色深浅等特征存在明显的差异。结合各酶带的相对迁移率（Rf值）和品种间的联合相似系数（S值）分析可知，（1）POD同工酶在同一株四棱豆不同节位成熟叶片中的表达具有高度的稳定性和相似性；（2）POD同工酶在所选的16个品种间存在明显的差异性，其中K0006和K0035、早熟二号，K0021和K0028品种间的S值在0.2~0.4之间，为最小值，即这两组品种间的亲缘关系最远，为优势杂交亲本组合；（3）同时阐明了POD同工酶在四棱豆中的相关分布规律，为植物分类或品种鉴定提供了科学依据，对杂交育种选材具有重要的实践指导意义。     

苜蓿雄性不育系及其回交后代同工酶分析

采用聚丙烯酰胺凝胶垂直板电泳技术对苜蓿雄性不育系及其回交后代进行过氧化物酶(POD)、酯酶(EST)同工酶分析。结果表明:(1)苜蓿雄性不育系及其回交后代叶的POD同工酶在现蕾期和开花期的酶带数较返青期多。返青期的酶活性较现蕾期和开花期强;MS-4及其回交后代叶的EST同工酶活性变化规律与POD同工酶谱表现相似;(2)在花发育的不同时期,花蕾为绿色时期时的POD同工酶酶活性最强,MS-4及其回交后代小花的EST同_T-酶酶带数较叶的多。刚开过的小花EST同工酶酶活性最强,F1、BC1代不育株都出现了母本MS-4所具有的POD、EST特征酶带;(3)从MS-4回交后代中所选育的不育株的POD和EST同工酶谱明显偏向于轮回亲本MS-4,说明通过回交使MS-4的某些性状在回交后代中进一步得到表现,因此,可以初步认定原不育系Ms4的不育性是可遗传的。     

水稻株系与亲本间灌浆期POD酶谱及遗传效应分析

通过复性电泳技术,对水稻子代与亲本在灌浆期的POD酶谱动态变化进行分析,结果表明：（1）灌浆期C的POD酶谱与亲本间表现出明显差异,C的POD带型偏A,总酶活变化规律与B相似。（2）灌浆中期C中检出1条52kD新酶带;灌浆后期仅C和A中检出53kD酶带,酶活C较A弱。（3）灌浆中期仅在A中检到的70~63kD弱酶活带区和灌浆中、后期仅B中检到的63~58kD弱酶活带区及42kD酶带,在C灌浆各时期均未检出。亲本间基因互作导致C的POD酶谱表达差异,这是育种希望得到的,对于新酶带和差异酶谱与C的新性状关系的进一步研究,将为水稻杂交育种提供重要的理论依据。     

过氧化物酶同工酶与棉花黄萎病抗性的相关研究

对20个来源及抗性不同的海岛棉和陆地棉品种和2个陆地棉(S)/海岛棉(R)杂交组合 的亲本、 F1、 F2世代的POX同工酶研究表明, 接种黄萎病菌前后, 棉花叶片中的 POX同工酶酶谱发生明显变化, 抗病品种与感病品种的阴性POX同工酶谱带均由原来的3 条 增 至6条, 但两者之间不存在明显差异; 阳性POX同工酶谱带接种前后均只有1条(     

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.