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1.
夏玉米主要穗部性状结构分析和高产育种探索   总被引:14,自引:0,他引:14  
利用17个玉米杂交种通过对7个穗部性状与产量进行相关和通径分析,结果表明:结实长、出籽率、穗长、行粒数、穗行数、千粒重与产量的相关系数均为正值且较大;出籽率、结实长、千粒重、穗粗、穗长对产量的直接通径系数也为正值且较大.因此,对产量影响较大的因素有出籽率、结实长和千粒重,提高出籽率和千粒重,增加结实长兼顾其它穗部性状是玉米高产的有效途径。  相似文献   

2.
采用NCII遗传交配设计,以昌7-2、郑58、PH4CV、PH6WC为测验种,与12份阿根廷抗粗缩病自交系和群体配制48个组合,2015、2016年分别在河南洛阳、新乡、山东聊城进行产量及相关性状测定。结果表明,根据产量等性状的一般配合力,遴选出3份较为优秀的自交系CA1109、CA1107、CA1108,其中,CA1109的产量、出籽率、百粒重、穗粗等性状一般配合力较高,但株高、穗位偏高;CA1107的百粒重、穗粗以及降低株高和穗位高等性状一般配合力较高,但延长了生育期,且行粒数、出籽率减少;CA1108增加百粒重、穗行数、穗粗一般配合力较高,但延长了生育期,增加了株高和穗位高和收获时子粒含水量。根据产量SCA效应值,初步判定属SS类的有CA1303、CA1109、CA1106、CA1104,属NS类的CA1301、CA1101、CA1102。被测系CA1109、CA1107、CA1108直接利用选育出高产组合的可能性较大。  相似文献   

3.
以属于5个杂种优势群的24个常用玉米自交系为母本(P1),优良玉米自交系T138-1及其秭妹系T138-2为父本(P2),杂交获得了48个组合。分析了亲本自交系的一般配合力、杂交组合的特殊配合力和总配合力效应,主要结果表明:不同组合各性状配合力存在极显著差异。P1亲本,除出籽率GCA外,其他性状差异显著或极显著。P2亲本,生育期、株高、穗粗、行粒数、穗位、棒三叶面积GCA差异显著或极显著。P1与P2互作间的SCA方差除出籽率和小区产量差异未达显著水平外,其余10个性状的SCA差异均极显著。P1亲本各性状一般配合力差别很大,P2亲本T138-1出籽率一般配合力效应高于T138-2,其它性状GCA值均低于T138-2。穗位高、穗长、穗行数、行粒数、秃尖、百粒重、出籽率SCA值与其性状均值之间达到了正的极显著或显著相关,受环境影响较大。各性状总配合力效应与实际田间表现基本一致,生育期、株高、穗位高、棒三叶面积、穗长、穗粗、行粒数、百粒重总配合力效应与小区产量正相关。  相似文献   

4.
玉米8个产量构成因素的通径分析   总被引:29,自引:5,他引:29       下载免费PDF全文
广成  薛雁  苟升学 《玉米科学》2002,10(3):033-035
组配成不完全双列杂交的90个组合用3次重复的随机区组设计对玉米穗长等8个产量组成因素与子粒产量的关系进行了遗传相关和通径分析.结果表明穗长等8个性状与子粒产量的遗传相关系数均为正值.其中,结实性与子粒产量的遗传相关系数未达0.05的显著水平,千粒重与子粒产量的遗传相关系数达到0.05的显著水平,其余6个性状与子粒产量的遗传相关系数均达到了0.01的显著水平.通径分析结果表明,8个产量组成性状对子粒产量的相对重要性依次为结实长>穗粗>出籽率>千粒重>行粒数>穗行数>结实性>穗长.选育夏播高产杂交种时,要重视选择果穗结实长、果穗粗、出籽率高的类型。  相似文献   

5.
以欧洲玉米种质BC8241Ht直选系南21-3及其改良系为材料,按NCⅡ杂交模式,分析了直选系南21-3及其改良系的株高、穗位高、穗长、穗粗、秃尖长、每穗行数、每行粒数、百粒重和单株产量9个性状的配合力。结果表明,经过遗传改良后获得的改良系多数性状的一般配合力得以提高,少数性状变化相对较小,个别性状还有变劣的趋势;改良系单株产量的遗传增益明显提高。  相似文献   

6.
几个玉米改良系主要农艺性状配合力和遗传参数的分析   总被引:14,自引:2,他引:14  
采用NCⅡ设计,对几个玉米改良系主要农艺性状进行了配合力和遗传参数分析.结果表明:388-2的产量性状的一般配合力最高,为较好的改良系;7922×388-2、吉853×388-2、Mo17×389-1、Mo17×387-1的配合力总效应较高.遗传参数分析表明:穗长、行数、秃尖长主要受加性基因控制;百粒重、单株产量、穗重主要受非加性基因控制。  相似文献   

7.
西南及四川区试玉米组合主要性状分析及育种对策探讨   总被引:15,自引:2,他引:15  
对2005年西南及四川区试玉米组合主要性状的分析结果表明,共有17个组合的小区产量显著或极显著高于对照品种川单13,高产组合的株高、穗位高、穗长、行粒数、子粒深度、穗行数和出籽率与对照品种存在显著或极显著差异。相关分析表明,除穗长和行粒数与单株产量显著或极显著正相关外,其余性状与单株产量的相关系数均未达显著水平。通径分析表明,各性状对单株产量的直接作用从大到小依次为穗长、穗行数、子粒深度、行粒数、株高、穗位高和出籽率,其中穗长和穗行数对单株产量的直接效应达显著或极显著水平。变异系数分析表明,高产组合间各性状变异都在一个较小的范围内。玉米突破性高产育种应加强种质的创新与改良,注重穗长、穗行数、子粒深度、行粒数和出籽率的选择,并把遗传改良的重点放在穗长上。  相似文献   

8.
通过向玉米辽旅群体中导入血缘相近、脱水速率快的9份欧美种质,构建成含有不同比例欧美种质的3份旅欧群体,能显著改善收获时含水量、出籽率、生育期、穗粗和穗行数等重要性状,且保持原始群体优良的产量一般配合力,显著提高出籽率、穗长和行粒数的一般配合力。杂种优势分析结果表明,旅欧群体所配制的组合有效提升出籽率、收获时含水量、生育期和其他穗部性状的杂种优势,与塘四平头类群的杂优模式存在极高的产量应用潜力,为改良本土种质资源适宜机械化收获和探索欧美种质新的杂优模式奠定基础。  相似文献   

9.
YJ7是江苏沿江地区农科所选育的优良玉米自交系,利用该自交系已育成一批优良组合。采用NCⅡ设计组配45个杂交组合,研究不同密度下(6.0万、7.5万、9.0万株/hm2)YJ7产量性状的配合力效应及杂种优势。结果表明,除穗粗、穗行数外,YJ7在高密度条件下产量性状一般配合力水平均较高,且随密度的增加而增加;YJ7×Mol17、YJ7×478杂478、YJ7×丹340这3个杂交组合在高密度条件下具有较高的特殊配合力、总体配合力,其杂种优势明显高于其他杂交组合。  相似文献   

10.
玉米11个农艺性状的通径分析   总被引:9,自引:0,他引:9  
广成  薛雁  何代元  刘强 《杂粮作物》2003,23(1):9-13
用不完全双列杂交法组配成35个组合,对玉米的生育期等11个性状与籽粒产量的遗传相关和通径进行了研究。结果表明,株高等7个性状与籽粒产量呈极显著正相关,生育期为显著正相关,穗位高和穗粗为正相关,但差异不显著,穗行数为显著负相关。通径分析结果表明:果穗结实长度等7个性状与籽粒产量的直接通径系数为正值,面千粒重等4个性状的直接通径系数为负值。在玉米高产育种中,要重视选择果穗结实长、籽粒行数多、果穗长和出籽率高的类型,适当注意穗位高等3个性状的选择,对千粒重等4个性状的选择可适当放宽。同时,也要注意到各性状间的相关性,把杂交种的各农艺性状协调到最佳程度。  相似文献   

11.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

12.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

13.
The review of the 2016–2017 marine pharmacology literature was prepared in a manner similar as the 10 prior reviews of this series. Preclinical marine pharmacology research during 2016–2017 assessed 313 marine compounds with novel pharmacology reported by a growing number of investigators from 54 countries. The peer-reviewed literature reported antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral activities for 123 marine natural products, 111 marine compounds with antidiabetic and anti-inflammatory activities as well as affecting the immune and nervous system, while in contrast 79 marine compounds displayed miscellaneous mechanisms of action which upon further investigation may contribute to several pharmacological classes. Therefore, in 2016–2017, the preclinical marine natural product pharmacology pipeline generated both novel pharmacology as well as potentially new lead compounds for the growing clinical marine pharmaceutical pipeline, and thus sustained with its contributions the global research for novel and effective therapeutic strategies for multiple disease categories.  相似文献   

14.
SUMMARY

Vitamin A, iodine, and iron deficiencies affect large numbers of people worldwide. A deficiency of one or more of these micronutrients adversely affects the physical and mental abilities of humans. South Asia contains a high percentage of these individuals, not just because of its large population, but also the prevalence of deficiency is higher there than in many other parts of the world. The reasons for the high rates of deficiency in South Asia are many, but they include inadequate availability of micronutrient-rich foods, sub-optimal dietary habits, and high rates of infection. Across the region, national plans vary from (a) increasing availability of appropriate foods, (b) introducing new dietary behaviors, (c) improving health status, and (d) directly addressing deficiency through intervention programs. The extent to which each of the countries is making progress toward the goals of these plans can help in understanding the priorities for future efforts to address micronutrient malnutrition. This article discusses the adverse effects of micronutrient deficiencies in humans with special reference to South Asia.  相似文献   

15.
Plains rough fescue ( F estuca hallii) is an important forage grass species in western Canada. Seed for use in pastures and ecological restoration is in high demand but supply is limited because F. hallii is an erratic seed producer. Seed producers require an understanding of the factors that influence flowering and seed set in this species. The aim of this study was to assess the effect of irrigation and nitrogen fertilization on the flowering and growth of F. hallii in a native rough fescue prairie in Alberta, Canada. Irrigation had a strong positive effect on seedhead density, whereas fertilization had limited effects on growth and reproduction of F. hallii. These results demonstrate that under field conditions, available moisture is likely to be a key factor driving flowering and seed production in F. hallii.  相似文献   

16.
Summary

Within the last three decades, the rice-wheat cropping system has triggered, and with time, aggravated soil micronutrient deficiencies in the Indo-Gangetic Plains (IGP). This has largely been due to the shift from an earlier rice and wheat monoculture with low yielding, long duration indigenous varieties, to an intensive rice-wheat rotation cropping system with short duration modern high yielding varieties on the same piece of land. The problems related to micronutrient deficiency in the IGP are more due to the size of its available pools in the soil rather than its total contents and are greatly influenced by crop management, or rather its mismanagement. Deficiency of zinc is widespread in the IGP, but with the extensive use of zinc sulfate, zinc deficiency has reduced in some areas of the region. Meanwhile, the deficiency of Fe, Mn and B has increased in the IGP. Deficiency of Cu and Mo is location specific and can limit rice and wheat yields. The adoption and spread of the rice-wheat system in permeable coarse textured soils, particularly in the western IGP, not only caused iron deficiency in rice but also resulted in the emergence of manganese deficiency in wheat. In highly calcareous and acidic soils, boron is the next limiting micronutrient in crop production after zinc. Bumper rice and wheat harvests in the past decade, the declining use of organic manures in the region and except for the widespread use of zinc sulfate, a general lack of awareness amongst farmers on micronutrient deficiency problems has contributed to micronutrients limiting rice and wheat yields in the IGP. Approaches to alleviating micronutrient deficiencies include matching the crop removals of the micronutrients with its replenishments through their respective external carriers, supplementation through organic sources and mobilization/utilization through cultivation of micronutrient efficient crop cultivars. Identification of efficient micronutrient carriers and finding the optimum rate, mode and time of its application is important in ameliorating the micronutrient deficiencies. This article reviews the extent of micronutrient deficiency and discusses various management options available to reduce micronutrient deficiency induced crop yield reduction for rice and wheat in the Indo-Gangetic Plains.  相似文献   

17.
Marine biomass diversity is a tremendous source of potential anticancer compounds. Several natural marine products have been described to restore tumor cell sensitivity to TNF-related apoptosis inducing ligand (TRAIL)-induced cell death. TRAIL is involved during tumor immune surveillance. Its selectivity for cancer cells has attracted much attention in oncology. This review aims at discussing the main mechanisms by which TRAIL signaling is regulated and presenting how marine bioactive compounds have been found, so far, to overcome TRAIL resistance in tumor cells.  相似文献   

18.
Summary Morphological and biochemical parameters that could be involved in resistance to late blight were studied in non-infected and in infected potato hybrids resulting from a cross betweenSolanum phureja, resistant toPhytophthora infestans, and a susceptibleSolanum tuberosum. Some morphological differences between resistant and susceptible hybrids, indicating a positive correlation between stem diameter and phloem thickness in the stem and resistance toP. infestans, were observed. The lignin content in the leaves of the resistant hybrid rose upon infection byP. infestans. In the leaves of the susceptible hybrid, a diminution of the lignin content could be observed upon infection byP. infestans. In the same context, peroxidasic activity raised upon infection byP. infestans in both resistant and susceptible hybrids. Further characterization of the hybrid clones based on the polymorphism of peroxidases was attempted using isoelectric focusing.  相似文献   

19.
Potato is an important crop, grown worldwide. It suffers from many pests and diseases among which late blight, caused by the oomycete Phytophthora infestans, is the worst. The disease is still causing major damage in many potato production areas and control is only possible by applying fungicides frequently. The knowledge on the molecular biology and genetics of the interaction between the plant and the oomycete is developing rapidly. These are relevant fields of study, currently dominated by the discovery of many resistance genes and numerous effector proteins and the analysis of their specific mode of action. These studies may yield essential information needed for the development of durable resistance. The long-term and worldwide effort to breed for resistance so far has had little effect. A novel breeding approach may change this. It is based on cisgenic modification (CM) consisting of marker-free pyramiding of several resistance genes and their spatial and temporal deployment yielding dynamic varieties that contain potato genes only. It is envisioned that this CM approach with potato’s own genes will not only prove societally acceptable but may also result in simplifications in the legislation on use of the CM approach. Various parties in the potato research arena intend to cooperate in this novel approach in a number of developing countries where potato substantially contributes to food security. The use of resources such as land, water and energy improves when the effect of late blight is markedly reduced.  相似文献   

20.
In an experimental breeding scheme to improve late blight (Phytophthora infestans) and white potato cyst nematode (Globodera pallida) resistance of tetraploid potato over three generations of crossing and selection, 15 clones survived the final selection, and these were derived from 15 great-grandparents. There was no direct selection for resistance to Potato virus Y (PVY), but 14 out of the 15 great-grandparents were resistant to PVY and three had extreme resistance. Thirteen of the 15 descendants had PVY resistance and one extreme resistance. This was within the range expected for a random (unselected) sample from the genotypes of the great-grandparents. Hence, we found no evidence for any positive or negative association between PVY resistance and the attributes selected. The conclusion is that laborious selection is not required in every generation when many parents have PVY resistance, including some with more than one copy of a PVY resistance gene or resistance at more than one locus. However, in the future, determining the major virus resistance genes present in potential parents in each generation using diagnostic molecular markers would prevent susceptible × susceptible crosses being made and maximise the number of resistant × resistant ones.  相似文献   

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