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1.
试验选用地方常用自交系甸骨11A、红玉米、长3、Mo17(未改良自交系)和导入热带玉米种质选育的8份自交系(改良自交系),每份改良自交系分别选定2个测验种,配制16个杂交种(改良杂交种),未改良系与选定2个测验种组配的杂交种(未改良杂交种)作为改良杂交种的相邻对照,对比法设计。改良自交系和未改良自交系、改良杂交种和未改良杂交种的性状观测值作为一对数据,按成对资料统计方法分析,t测验。结果表明:甸骨11A导入Suwan1、5-56的改良自交系与红玉米杂种优势较高,红玉米导入Suwan1、EVT5的改良自交系与甸骨11A杂种优势较高,长3导入Suwan1、墨黄9的改良自交系与海014的杂种优势较高。改良自交系主要性状变化表现为生育时期延后、单株产量增加。未改良自交系熟期越早,改良自交系及改良杂交种生育时期延后时间越长,改良自交系单株产量增加幅度越大。改良自交系及其改良杂交种的玉米大斑病、茎腐病的抗性有了较大提高。  相似文献   

2.
对导入Suwan1玉米种质选育自交系的评价   总被引:3,自引:4,他引:3  
试验选用地方常用系甸骨11A、红玉米、长3、Mo17、黄早四导入Suwan1种质选育的自交系5份,分别与选定测验种杂交。通过改良系与未改良系、改良杂交种与未改杂交种的比较,结果表明改良系生育期延后,穗行数增加、百粒重下降、单株产量提高,增产幅度在3.9%~43.5%。改良系与选定测验种的杂种优势表现:甸骨11A改良系与红玉米、红玉米改良系与甸骨11A、长3改良系与海014的产量对照优势显著高于相邻对照;红玉米改良系与C500、Mo17改良系与B73和444的产量对照优势为正,长3改良系与龙抗11,黄早四改良系与Mo17和8112的产量对照优势为负,但与相邻对照差异均不显著;甸骨11A改良系与早大黄的产量对照优势为负并差异显著,其杂交种丝黑穗发病率25.3%。  相似文献   

3.
导入热带、亚热带玉米种质选育自交系及其杂交种的研究   总被引:2,自引:0,他引:2  
试验选用8份导入热带、亚热带种质选育的自交系,每份自交系分别选2个测验种,采用对比法设计。结果表明:系14导入中甸二黄马/EVT5、墨黄9选系和Mo17、吉63组配的杂交种产量对照优势均为正值。其中系14导入墨黄9选系杂交种的对照优势分别为15.8%和14.5%。自330导入5-56、辐苏1号选系和Mo17、旅九的杂交种产量对照优势均为负值。B73导入5-56、辐苏1号选系和Mo17、黄早4的杂交种产量对照优势均为正值。5003导入5-50、4-6选系和Mo17、E28的杂交种,除5003导入5-50选系×E28的对照优势为正,其它3个组合均为负值。  相似文献   

4.
采用NCⅡ遗传交配设计,以分属于5个杂种优势群的自交系昌7-2、DH34、Mo17、郑58和丹988为测验种,与5个欧洲玉米种质BRC选系组配25个杂交组合,分析5个欧洲玉米种质BRC选系的主要农艺性状的配合力及杂种优势。结果表明,自交系BRC-1和BRC-5单株产量及相关性状一般配合力表现较好,在玉米育种中有较大的利用潜力;组合BRC-5×Mo17、BRC-6×DH34和BRC-1×丹988是产量及相关性状特殊配合力综合表现优良的组合;BRC-5×DH34、BRC-1×DH34、BRC-1×丹988、BRC-6×DH34和BRC-1×昌7-2是单株产量总配合力和杂种优势表现突出的组合。BRC种质选系或BRC改良自交系可与旅大红骨、塘四平头、PN78599类群的玉米自交系杂交组配出强优势玉米杂交种。  相似文献   

5.
热带玉米Suwan群体的遗传特性及育种潜势   总被引:1,自引:0,他引:1       下载免费PDF全文
基于对玉米Suwan 1、Suwan 3和Suwan 5群体的植物形态学农艺性状特征特性调查与玉米Suwan 1群体的遗传潜势研究,对玉米Suwan 1、Suwan 3和Suwan 5群体的遗传特征特性和Suwan 1群体进行方差分析。结果表明,热带玉米Suwan 1群体的综合性状包括育种产量潜力、基因加性效应积累等方面优于Suwan 3和Suwan 5群体;基于导入玉米Suwan 1群体后的杂种优势模式及产量表现,根据贵阳市两年田间产量鉴定结果发现,将Luda Red cob/Suwan 1类群合并的新种质与PB类群的平均产量最高。根据Suwan 1种质导入我国5大玉米类群后顶交种的配合力和杂种优势组型,经过2年多点的田间试验鉴定得出强杂种优势组型PB×Luda Red cob/Suwan 1、CIMMYT×Reid/Suwan 1、CIMMYT×Luda Red cob/Suwan 1和PB×Reid/Suwan 1。同一地点不同年际间田间试验鉴定,试验点次较少,有必要对优良热带玉米Suwan 1群体的遗传潜势及种质改良利用等进行深入的、更全面的研究。  相似文献   

6.
国外玉米种质的引进、利用与改良是我国玉米杂交育种不可缺少的重要环节,也是育种成败的关键.选用从欧洲引进的21个玉米杂交种,在经过产量比较鉴定和农艺性状综合评判后,选取其中的BC8241H1作为选系基础材料,选育出了优良玉米自交系南21-3,并组配育成了5个优良玉米杂交种供我国西南山区推广应用.针对南21-3部分性状的缺陷,分别导入Tuxpeno、Lancaster和Reid种质对该系实施改良,并选育出了系列改良系.实践证明,BC8241Ht这份欧洲玉米种质是优良的,利用改良的效果也是明显的。  相似文献   

7.
分析了20世纪70年代至今Tuxpeno、Suwan、墨黄9号和西南山区地方品种等(亚)热带种质选系及改良系在中国玉米育种和生产上的研究与应用.结果表明,优良玉米群体Tuxpeno、Suw明和墨黄9号等,优良玉米自交系S37、S11、S1611、QB39、毕405、449、D19、M9、五-151、J51和5311等,优良玉米杂交种恩单2号、会单4号、雅玉2号、桂单19、兴黄单89-2、交三单交和黔单13等,对中国玉米育种和生产产生了一定影响,其间利用的主要杂优模式为Suwan(Tuxpeno等)×西南山区地方品种选系或温改地选系或典型温带种质选系等.新世纪如何继续沿用原有杂优模式和利用(亚)热带种质改良中国骨干类群并创建新的杂优模式都值得玉米育种家高度重视,为中国玉米育种和生产再上新台阶奠定基础。  相似文献   

8.
20份玉米种质选系的利用潜力分析   总被引:4,自引:4,他引:0  
采用NCII遗传交配设计,以黑龙江省5份常用骨干自交系为测验种,与20份欧洲玉米种质选系配制100个组合,在黑龙江省3种不同生态环境下,分析20份欧洲玉米种质选系主要性状的配合力及杂种优势。结果表明,被测系之间的一般配合力效应差异达极显著,T04、T16-2、TF32和T218-4的产量及相关性状一般配合力表现优良,在玉米育种中具有较大的利用潜力;TF32×四-444在产量特殊配合力和杂种优势上均为最大值。与对照比较,杂种优势大于10%的组合大多为欧洲玉米种质选系×塘四平头类群自交系,说明欧洲玉米种质与塘四平头类群种质之间具有较强的杂种优势。  相似文献   

9.
刘志全 《玉米科学》2003,11(Z1):010-014
玉米是泰国主要的谷类作物,2000年种植面积估计为130万hm2,子粒产量约448万t.杂交种种植面积占到玉米总面积的85.08%,以单交种为主,占到总杂交种的74%,其次为三交种.玉米生产主要限制因素有生物的如高粱霜霉病、南方锈病、小斑病、大斑病、茎腐病、玉米螟等;非生物因素有干旱胁迫等.玉米种质改良和品种遗传改良开始于1950年,主要从事单位为农业厅和肯色萨大学.先后育成Suwan1、Suwan2、Suwan3、Nakhon Suwan1、Suwan5等改良群体和Suwan Complex、KS23 等宽基综合种,并从中选育出Ki21、Ki45、Ni1等优良系,组配出了Suwan2301、Suwan3851、Nakhon Sawan72等优良杂交种.分别应用10个群体双列杂交法、顶交法和优良适应品种与外引种质杂交法等,确定了如下几个杂种优势模式:(Suwan1、Suwan3)×(Caripeno DMR、KS6);(Suwan1和 Suwan3的选系、KS6选系)×(Ki21、Mo17衍生系);[KS23(S)C2、Suwan5(S)C3]×[Suwan1(S)C11]。  相似文献   

10.
热带亚热带种质不同导入量对玉米自交系配合力的影响   总被引:16,自引:5,他引:16  
热带亚热带玉米对温带玉米在性状上有较大互补性。种质导入可进一步丰富温带玉米遗传基础,改善某些重要性状.如抗倒伏,持绿性等。热带亚热带种质导入量以1/4~1/8较好,导入过多会使配合力降低,导入过少会使优良性状散失、因此掌握适当的导入量是选系成败的关键。与温带种质材料一样,不同的热带亚热带种质材料优劣程度也存在很大差异,只有选用表现优良的种质,导入优良的温带玉米,才会收到良好的选系效果.  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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