小麦旗叶性状与产量因素的相关与回归分析

以59个小麦品种(系)为试材,对旗叶性状与产量及产量因素作了相关与多元回归分析.结果表明,小麦旗叶的长、宽、叶面积、与茎杆的夹角、叶绿素含量与穗粒数、千粒重、穗粒重、产量等性状间的相关系数分别达显著或极显著水平,r=0.4851～0.7481.建立了旗叶性状与产量及产量因素的最优多元回归方程.     

不同年代小麦产量性状与农艺性状的相关性比较

为研究不同年代小麦的主要农艺性状与产量性状之间的相关性,对4个不同年代78个小麦品种的主要性状进行调查分析,得出如下结论:随着年代的推进,小麦株高的降低趋势明显并趋于稳定,旗叶长呈缓慢下降趋势,旗叶宽、旗叶面积先增长后趋于稳定。在各年代中,株高与穗粒数、千粒质量和结实小穗数呈不显著正相关,与不孕小穗数呈不显著负相关。旗叶宽和旗叶面积与穗粒数、千粒质量和结实小穗数呈一定的负相关性,并与不孕小穗数呈一定的正相关性。因此,适当降低株高,增加旗叶宽和旗叶面积,对提高小麦产量有一定的推进作用。穗粒数和不孕小穗数的变异系数均较高,有较大的选择空间。     

小麦茎质系数的基因型差异及与产量性状关系的初步研究

利用11个不同的小麦基因型,对茎质系数的基因型差异及其与产量性状的关系进行了初步研究.结果表明茎质系数在小麦基因型间存在极显著差异,与单茎草重、穗粒数、千粒重、穗粒重呈极显著的正相关,与穗数、经济系数呈极显著的负相关,重穗型品种的茎质系数极显著地高于多穗型品种,但其经济系数、子粒产量/草产量(库源比)极显著地低于多穗型品种,选育中间型品种可以实现高产与抗倒的有机结合.     

小麦旗叶和芒的遗传及其与产量性状的相关性研究

通过对20个小麦品种（系）的研究表明,旗叶、芒对产量形成影响较大。旗叶、芒具有一定的遗传变异度,旗叶性状遗传力中等,芒遗传力较高。旗叶长、旗叶宽、旗叶面积、穗平均芒长均与穗粒重呈显著正相关;旗叶开张角、披垂度与穗粒重呈显著负相关。旗叶长与开张角、披垂度正相关,旗叶宽与开张角、披垂度负相关。育种中可将旗叶宽作为良好的株型性状加以选择。     

2种穗型小麦品种若干性状差异的比较

为了探明胶东地区适宜的小麦品种类型与育种方向,通过11个不同的小麦基因型,采用t测验法对2种穗型小麦品种的若干性状差异进行了研究。结果表明:大穗型品种的单茎草重、茎质系数、穗粒数、千粒重、穗粒重比多穗型品种高0.958 g、0.011 g/cm、5.354粒、5.460 g、0.504 g,均达到极显著水平;多穗型品种的单位面积穗数、经济系数和群体产量比大穗型品种高289.847万/hm2、0.027、859 kg/hm2,均达到极显著水平。在胶东地区生态条件下,应以分蘖力中等、茎秆粗壮、成穗率高、产量三因素协调的多穗型品种为主攻方向。     

源—库变化对小麦籽粒性状和干物质积累的影响

以不同历史时期的小麦品种为材料,研究了源—库变化对小麦籽粒性状和干物质积累的影响表明:穗粒重、千粒重、最大籽粒体积、皱缩指数、单茎生物量和草重有明显的品种间差异.剪叶减源,使穗粒重、最大籽粒体积、千粒重和生物量下降。剪除部分小穗减库,使剩余籽粒的最大体积和千粒重明显增加。新老品种的开花期单茎生物量相同,对减少库的反应基本一致。近期品种开花后单茎干物质积累较多,对源的减少较敏感.要在现有品种基础上提高产量潜力,不但要增加库,而且要增加源     

小麦三雌蕊近等基因系的主要农艺性状分析

为充分利用小麦三雌蕊品系的优良性状,全面分析小麦三雌蕊基因pis1对其农艺性状的遗传效应,本研究对小麦三雌蕊近等基因系CSTP,CM28TP,MY29TP和NM9TP及其相应的轮回亲本的主要农艺性状进行了分析。结果表明,各近等基因系与其轮回亲本在株高、茎粗、旗叶长、旗叶宽、有效穗数、穗长以及小穗数等7个农艺性状上差异不显著,除CSTP外,其它3个近等基因系的穗粒数明显高于其轮回亲本。但千粒重和小区产量均低于轮回亲本。相关性分析表明,小区产量与千粒重呈极显著正相关。而小区产量和千粒重都与穗粒数呈不显著的正相关,即仅提高穗粒数不能有效的提高产量。因而要利用小麦TP品系进行育种研究,其首要目标是提高千粒重。聚类分析表明,近等基因系与相应的轮回亲本聚在一起,这说明构建的近等基因系是成功的。     

矮秆CHA杂种小麦优势分析

本文对９个矮秆ＣＨＡ杂种小麦产量及相关因素的优势表现进行了分析。产量最高优势为６．１％，穗粒数普遍表现明显超标优势，亩穗数表现负优势，千粒重优势很不一致。穗长增加，结实小穗数增多，穗粒重有很强的优势，表现出大穗，多花多实特性，主茎旗叶，倒二叶面积增大，光合能力强，收获指数高，库源关系比较协调。     

抗条锈矮秆大穗型小麦茎叶穗遗传及各性状相关研究

以4个矮秆大穗型小麦材料为母本，6个高产小麦为父本，采用不完全双列杂交设计，对小麦15个茎叶穗农艺性状进行遗传分析。结果表明：15个农艺性状的表现都是由加性和非加性基因共同决定的。15个性状遗传力均较高，除旗叶宽、旗叶面积和单株粒重三性状外，其余性状主要由加性基因决定。除叶宽和结实小穗两性状外，其余各性状的GCV均较大，表明对其选择和改良的潜力较大。各茎叶穗农艺性状一般配合力间存在不同程度的依存关系。指出小麦高产育种应注意协调好提高结实小穗、穗长、每穗粒数与提高穗下节长和穗颈节长以及穗长与单株穗数问的关系。     

^60Co-γ辐射处理普通小麦M3代性状变异分析

用300 Gy的60Co-γ射线辐射小麦品种涡9722的干种子.对M3代穗行的穗数、株高、穗长、小穗数、退化小穗数、叶长、叶宽、叶面积、旗叶基角、穗粒重、千粒重和产量等性状进行了变异分析、聚类分析.结果表明,M3代群体穗数、株高、穗长、退化小稳数、叶长、叶宽、叶面积、旗叶基角、穗粒重和产量总体有上升趋势,小穗数、千粒重有下降趋势.所调查的所有性状均发生正向变异,穗数、穗长、小穗数、旗叶基角、产量、千粒重发生负向变异.聚类分析表明,当遗传距离为49.09时,可将105个穗行分为9个类群.     

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.