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1.
Hundreds, if not thousands, of species of insects use wild sunflowers (Helianthus spp.) for food and/or shelter. Fortunately, the majority of these species do not attack the common annual sunflower, H. annuus L.; of those that do, a relatively small percentage actually become an economic threat to profitable sunflower cultivation. This paper discusses the species of insects that are known pests of cultivated sunflower, their injury to plants, the effects of their injury on seed and oil production, and control strategies that are used for their management.  相似文献   

2.
《Field Crops Research》1992,30(3-4):231-270
Sunflower (Helianthus annuus L.) is among the most important oil crops in the world. Due to its low to moderate production requirements, high oil quality, protein content, and utilization of all plant parts, it is grown on about 14 million ha. The major sunflower-producing countries in the world are the Soviet Union, Argentina, China, the United States, France, Spain, Romania, Turkey and Hungary. Sunflower became an oil crop around the end of the 19th century, when ‘popular selection’ was practiced in several parts of Russia to improve sunflower populations grown at that time.

The most important contributions to the development of sunflower were made by Pustovoit and Jdanov in the Soviet Union, who increased the oil concentration in sunflower seed above 500 g kg−1. Leclercq of France discovered the first usable sourccytoplasmic male sterility in a cross H. petiolaris Nutt. × H. annuus L. and Kinman of the United States developed fertility restorer lines RHA 265 and RHA 266 which allowed practical development of sunflower hybrids.

When starting a breeding program, it is useful to design a model of the desired hybrid and then strive to develop the envisaged model as closely as possible. It is also advisable to direct breeding efforts toward a limited number of economically important traits. These should include: (1) components of seed and oil yield: the number of seeds per plant, test weight, 1000-seed weight, low husk content and high oil concentration in the seed; (2) architecture of the sunflower plant: plant height, head size and shape, angle of the head, leaf area and leaf canopy; (3) increased harvest index: oil quality, protein concentration and quality, early maturation, short stem and uniform height; and (4) resistance to diseases and drought using wild sunflower species.

Mass selection, a method of selecting desirable plants from a population on the basis of phenotypic traits, is still in effective method in sunflower breeding. Recurrent selection appears to be a promising method of increasing the frequency of desirable genotypes in a source population.

Genetic variability of the cultivated sunflower may be increased by interspecific hybridization with wild sunflower species. The inclusion of wild species programs is difficult because of differences in chromosome number (2n, 4n, 6n) and incompatibility. These obstacles have been overcome by embryo culture and other tissue culture techniques. Generally, the use of new technologies in sunflower breeding is imperative, particularly in regard to the introduction of resistance genes to diseases and insect pests.  相似文献   


3.
The cultivated sunflower is considered to be a species very recalcitrant to various methods of biotechnology, although substantial progress has been made in recent years. For example, very efficient embryo culture techniques are available for obtaining numerous wide crosses which can be very valuable for broadening genetic variation in sunflower. In particular, interspecific hybrids have been demonstrated to be a unique source for creating “new” traits, like cytoplasmic male sterility (CMS) or resistance against devastating diseases, such as Sclerotinia rot. The succesful regeneration of entire plants from cultured somatic tissue or even single cells, i.e. protoplasts, has been demonstrated for specific genotypes. Furthermore, the recovery of androgenetic haploid and doubled haploid plants is basically feasible in sunflower, although the rate of regeneration strongly depends on genotype. Particular progress has been made in the field of “genome characterization”, by using both biochemical and molecular markers. In particular, the chloroplast and mitochondrial genomes have been analyzed and described in detail. Such analyses built the foundation for future “marker-based selection” and for the identification and isolation of specific genes as candidates for “genetic engineering”.  相似文献   

4.
Within the past decade, the desire for alternative sources of fuels, chemicals, and other industrial materials has received increased attention. Sunflower (Helianthus annuus L.) oil has the potential to be improved for nutritional and industrial purposes through selection and breeding. The narrow genetic base of cultivated sunflower has been broadened by the infusion of genes from wild species, resulting in a continuous improvement in agronomic traits. The genus Helianthus is comprised of 51 species and 19 subspecies with 14 annual and 37 perennial species. Interest in using wild species in breeding programs has increased, but concerns about the introduction of low oil concentration and quality from the wild species persist. Two annual desert species, Helianthus anomalus Blake and H. deserticola Heiser, are excellent candidates for increasing oil concentration and enhancing quality based on their adaptation to desert environments. The objective of this study was to collect achenes of H. anomalus and H. deserticola from the desert southwest USA and assess their potential for improving oil concentration and quality in cultivated sunflower. The sunflower collection took place from 16 to 23 September 2000 and covered a distance of 4100 km in three states: Utah, Arizona, and Nevada. The only H. deserticola population collected had an average oil concentration of 330 g/kg, whereas the two populations of H. anomalus had an oil concentration of 430 and 460 g/kg, the highest concentration recorded in any wild sunflower species. The linoleic fatty acid concentration in the oil of H. anomalus populations was uncharacteristically high for a desert environment, approaching 700 g/kg. A linoleic acid concentration of 540 g/kg in H. deserticola was more typical for a desert environment. H. anomalus has the largest achenes and the highest oil concentration of any wild sunflower species, and the same chromosome number (n = 17) as cultivated sunflower. These features will facilitate the introduction of genes from this wild annual progenitor into cultivated sunflower. The lower saturated fatty acid profile in this species is also a desirable trait offering the potential to reduce saturated fatty acids in cultivated sunflower. Further research will be needed to determine the inheritance of the fatty acids and oil concentration. Other agronomic traits will need to be maintained during the introgression of these traits into cultivated sunflower oil.  相似文献   

5.
Cultivated sunflower (Helianthus annuus L.) is prone to many diseases caused by fungi, bacteria, and viruses, of which the most detrimental are those caused by fungi. Two of the most important fungal pathogens are Sclerotinia and Phomopsis. Within the genus Sclerotinia, both S. minor and S. sclerotiorum cause a basal stalk rot and subsequent wilt of sunflower, with S. sclerotiorum more widely distributed around the world. Sclerotinia sclerotiorum also incites a head rot and mid-stem rot of sunflower. Since Sclerotinia spp. have a very wide host range and can persist in soil as dormant sclerotia for up to 10 years, the pathogens have been extremely difficult to control with either generic resistance or fungicides. The most effective control is the use of long rotations, tolerant hybrids, and sclerotium-free seed. Gray stem spot is a relatively new disease of sunflower first observed in the early 1980s in Yugoslavia and now considered the most devastating sunflower disease in eastern Europe. Symptoms include large stem cankers and subsequent wilt. Phomopsis helianthi has been identified as one incitant of gray stem spot, but another Phomopsis species may also be involved, both in Europe and in the United States. Foliar fungicides can control gray stem spot, but the development of resistant hybrids has been much more cost-effective.  相似文献   

6.
采用复合油葵杂交种LD06 F1选株自交,在其F2中,有粉株和不育株成对杂交后,用菊芋(H.petiolaris)的全DNA加渗透液的混合液按时涂抹已授粉的葵盘柱头。经多代分离选育,育成了不育系CMSUA5-1和相应的保持系UB5-2。CMSUA5-1与现有不育系CMSPET-1的恢复系杂交多代试验中,不能被CMSPET-1的恢复系所恢复,证明现有的恢复系与新选出的恢复系不同,新选出的恢复系UR5-3只能恢复CMSUA5-1,说明UR5-3是一个新型栽培向日葵的恢复系。  相似文献   

7.
以向日葵优良群体为母本,具有耐黑斑病基因的向日葵野生种为父本进行杂交,利用幼胚培养技术对远缘杂交后代进行胚拯救,从而获得具有耐黑斑病基因的5个遗传群体.在这些群体中,F1发病株率比CK降低96.5%、F2发病株率比CK降低86.6%.在抗黑斑病遗传群体中,运用轮回选择结合抗黑斑病鉴定,选育出6个抗黑斑病自交系,实验室接种发病率比CK降低96.4%,田间自然发病率仅为1%.  相似文献   

8.
辣椒(Capsicum L.)属于重要的蔬菜和香料作物,在世界范围广泛栽培.种质资源是育种和生产的基础,开展辣椒属叶绿体基因组特征研究对阐明辣椒种质资源遗传多样性、培育和改良栽培品种具有重要的理论和实践价值.本研究从NCBI数据库下载13个辣椒属物种叶绿体基因组序列,利用REPuter、MISA和mVISTA等软件,对...  相似文献   

9.
Out of 1 989 wild accessions sown in seed boxes for screening, only 1 003 wild accessions with good germination were screened against brown planthopper (BPH), Nilaparvata lugens (Stål) under greenhouse conditions. The collection comprised of accessions from 11 wild species and African cultivated rice. The germplasm was screened for BPH following standard seed box screening technique in the greenhouse. As many as 159 accessions were identified as resistant during the year 2012 based on one year screening. A selected set of BPH resistant accessions were screened again during 2013. Based on the two years screening, seven accessions of O. nivara (AA), one accession of O. officinalis (CC), seven accessions of O. australiensis (EE), five accessions of O. punctata (BB and BBCC) and nine accessions of O. latifolia (CCDD) were confirmed to be resistant to BPH. So far no BPH resistance genes have been identified and designated from O. nivara and O. punctata, hence these may act as new sources of resistance.  相似文献   

10.
Summary The narrow genetic base of the cultivated potato is a severe constraint for potato breeding. Wild tuber-bearing species constitute an important source of genes for resistance to diseases and pests as well as abiotic factors. Seven interspecific hybrid populations were generated from crosses between diploidTuberosum clones and four wild species:Solanum berthaultii, S. gourlayi, S. tarijense andS. vernei, and evaluated in a field experiment in Burgos (Spain) as a way to broaden the genetic base of the cultivated potato. Good tuberization ability and great variability for yield within the different families were detected. Hybridization with the wild species resulted in high levels of PVY resistance inS. berthaultii andS. vernei hybrids and a large increase of dry matter content in all populations except theS. berthaultii hybrids.  相似文献   

11.
The genetic resources available for the improvement of the cultivated potato (Solanum tuberosum) are reviewed along with progress in their utilisation. The conclusions are as follows. The wild and cultivated species of potato have been utilised in potato breeding to good effect, but only a very small sample of the available biodiversity has been exploited. New knowledge and technology will open possibilities for much greater use of these genetic resources in breeding. The strategy for utilising the cultivars native to Latin America will either be the introgression of desirable genes or the direct use of parents from improved populations, depending on how far modern S. tuberosum cultivars have genetically diverged from them and the extent to which S. tuberosum cultivars have been improved in the process. Molecular marker-assisted selection will be used for faster introgression of desirable genes from wild species, and the possibility exists of moving genes directly from wild species to cultivated potato with transgenic methods. New cultivars will continue to come from crosses between pairs of parents with complementary features but adapted to local growing conditions. However, increasingly these parents will possess desirable genes which have been introgressed from wild species and may also be from complementary groups of cultivated germplasm to exploit hybrid vigour. Successful cultivars may be genetically modified, if consumers see benefits in the use of the technology, to introduce genes not present in cultivated potatoes and their wild relatives to achieve novel biochemistry and further desirable improvements.  相似文献   

12.
Inter simple sequence repeat(ISSR) polymorphism was used to determine genetic diversity and phylogenetic relationships in 90 genotypes of wild and cultivated species of Oryza from different geographical regions of the world. In all the 17 primers used in ISSR-PCR, a total of 11 464 bands were amplified at 253 band positions/loci. The primer UBC-809 amplified the maximum bands(1 059) at 21 band positions. UBC-810 and UBC-835 amplified the minimum of 391 bands each at 7 and 14 band positions, respectively. The mean polymorphism information content ranged from 0.44 to 0.84 and resolving power ranged from 8.69 to 23.53. Un-weighted pair group method with arithmetic mean dendrogram and population structure based on the 17 primers separated all genotypes into 4 major clusters with a genetic similarity of 53%–100%. The first two clusters consisted of 30 O. rufipogon accessions each. In the third cluster, O. nivara and O. longistaminata grouped as one sub-cluster and all other O. nivara accessions and cultivars grouped as another sub-cluster. The fourth cluster had only five O. rufipogon accessions which can be a source of new genes. Four sub-populations were identified within O. rufipogon and two sub-populations within O. nivara at K = 7. A subset of six primers with high resolving power values were the most informative and grouped all genotypes almost similarly as the 17 primers did. Use of these six highly informative primers in ISSR-PCR is a cost effective and robust method for assessing genetic diversity in large germplasm collections of wild rice species.  相似文献   

13.
野生稻是栽培稻的野生近缘种,作为重要的基因资源,具有诸多的优良性状,如野生稻对病虫害的抗性、对各种逆境的耐受性以及胞质雄性不育等,已被广泛应用于现代栽培稻的育种改良,成为栽培稻遗传改良的丰富基因源和不可替代的物质基础。本文综述了野生稻优良基因的发掘和种质资源的利用现状,总结了野生稻保护和利用目前存在的问题,并对其在水稻育种中的应用潜力做出了展望。  相似文献   

14.
Wild potatoes are important sources of genes for resistance to disease and insect pests. A collection of wild Mexican and South AmericanSolarium species from the US potato Genebank was evaluated under laboratory and/or field conditions for their reaction to late blight (Phytophthora infestans), Colorado potato beetle (CPB,Leptinotarsa decemlineata Say), and blackleg (Erwinia carotovora subsp.atroseptica (van Hall) Dye) in order to identify individual genotypes with multiple resistance genes. Late blight inoculations using aggressive isolates (US-8/A2 and US-11/A1 mating types) of P.infestans revealed a wide range of variation for resistance between and within the accessions of the wild species tested. For late blight, susceptible as well as moderately to highly resistant genotypes were observed in all the species tested. However, at least one accession from the three Mexican and one South American wild diploid species tested showed a relatively uniform high level of resistance toP. infestans. These includedS. bulbocastanum, S. pinnatisectum, S. cardiophyllum, andS. circaeifolium. Two accessions from South American speciesS. commersonii were highly susceptible to late blight. For the Colorado potato beetle test, only one species,S. pinnatisectum appeared uniformly resistant to CPB under field conditions. Results of screening for blackleg resistance showed that there were major differences between genotypes in the wild species. Accessions ofS. circaeifolium PI 498119 andS. bulbocastanum PI 243504 were identified as having significantly higher blackleg resistance than cultivated potato and the other wild species tested. However, genotypes from these two accessions were more susceptible to late blight and CPB. Characterization of theP. infestans isolate P1801C.16 used for late blight evaluation and multi-locus isolate tests using US-8/A2 and US-11/A1 races revealed that the resistance inS. pinnatisectum genotypes tested corresponded to a race-non-specific genetic system, which was different from any existing R genes.Solanum pin-natisectum genotypes with both high levels of late blight and CPB resistance as well as blackleg resistance genotypes identified in the present study represent a diverse gene pool that may be useful for development of new potato cultivars with multiple disease and insect resistance. The potential utilization of these valuable sources for improvement of cultivated potato is discussed.  相似文献   

15.
The grain oils extracted from six genotypes of Cynara species: two globe artichokes (Cynara scolymus L.), two cultivated cardoons (C. cardunculus L. var. altilis DC.) and two wild cardoons (C. cardunculus L. var. sylvestris Lam.), were analysed in order to ascertain their alimentary value. Oil yield, moisture, acidity, peroxide number, UV spectrophotometry and CIE colour parameters, fatty acids, phytosterols and -tocopherol were determined by standard methods. Cynara species which are most promising in terms of quality and quantity of oil were the cardoons, especially those belonging to the wild cardoon genotypes. Triacylglycerols were the dominant constituents together with very little amounts of phospholipids and glycolipids. The high content of oleic and linoleic acids in a balanced ratio, and the low amount of free acids, peroxides, saturated and linolenic acids ensure a good alimentary quality. Distribution of phytosterols was typical of oil from grain of Asteraceae such as sunflower and safflower. Moreover the optimal -tocopherol content offers a guarantee of stability against oxidation.  相似文献   

16.
花生是世界上重要的油料作物之一。与栽培种相比,花生野生种具有较高的遗传多样性,能够适应一系列复杂环境,是抵抗生物胁迫和非生物胁迫的重要基因来源。多项研究表明,花生野生种对根结线虫病、晚斑病和锈病具有较高抗性。本文综述了野生花生的种类以及花生栽培种起源种相关研究进展,总结了野生花生对花生病害的抗性以及在育种中应用。结合花生基因组学最新研究,展望了花生野生资源的利用前景。  相似文献   

17.
向日葵锈病严重影响向日葵的产量。为了找到抗锈病相关基因,根据已知NBS-LRR型抗病基因保守结构域P-loop和GLPL设计简并引物,以接菌的抗病向日葵品种CM29叶片的cDNA为模板进行扩增。通过克隆转化得到10个具有连续开放阅读框的RGA,经系统进化分析将其分为TIR-NBS-LRR和non-TIR-NBS-LRR两种类型。对其氨基酸序列进行多重序列比对结果显示所获得的RGA具有典型的NBS-LRR型抗病基因保守结构域即P-loop、kinase-2a、kinase-3a和GLPL结构。运用BLASTX分析这些结果,表明其RGA与已知的抗病基因相应保守区域的同源性为18.1%~51.1%,说明它们可能与抗病功能基因具有密切联系。  相似文献   

18.
Sunflower (Helianthus annuus L.) is a crop native to North America for which there are no genetically modified commercial varieties. Some of the transgenic traits incorporated in other crops have already been subjected to research and experimentation in sunflower. Several new traits have also been noted, with the most relevant of these being the aim to increase latex production. GM sunflower release would modify crop management through improved mineral nutrition, weed control, insect and disease resistance, and product quality. In this research, the traits investigated were reviewed and analyzed in connection with main crop constraints. These characters could potentially influence agro-ecosystem components and produce a significant environmental impact. In regions where sunflower coexists with wild relatives this situation could affect germplasm resources, with this being especially important at the centre of origin and where Helianthus populations established in Africa, Asia, and Europe.  相似文献   

19.
The peach-potato aphid, Myzus persicae, provides an excellent demonstration of how genetic and ecological factors can interact to determine the dynamics of resistance and influence success of resistance management. The diversity of resistance mechanisms, based on both enhanced detoxification of insecticides and modifications to their target sites, that this species shows is now well understood at the genotypic, biochemical and molecular levels. These developments have yielded rapid and precise methods for detecting individual mechanisms, and for monitoring frequency changes in the presence and absence of insecticide selection. One factor influencing the prediction of these changes in the UK is the occurrence of prolonged periods of parthenogenesis in M. persicae, which results in non-random associations between particular resistance genes through the absence of genetic recombination. This has important implications for the rate at which resistance genes can accumulate in populations under selection by insecticides, and also for the speed at which they will decline when selection is relaxed. Although it is becoming apparent that resistance can be associated with various fitness costs, the relative contribution of individual resistance genes to these effects is still under investigation. However, the overall effect of the ‘ups’ and ‘downs’ of resistance in M. persicae, in the UK at least, has been to help maintain resistance phenotypes at manageable levels in most seasons. Unfortunately, the increasing genetic diversity of resistance in this species is progressively eroding the supply of effective insecticides. This in turn highlights the importance of ensuring sufficient chemical diversity to combat existing resistance mechanisms and to restrict the use of novel insecticides in order to sustain their effectiveness.  相似文献   

20.
石斛属(Dendrobium Sw.)为兰科(Orchidaceae)兰亚科(Subfam. Orchidoideae)植物,在我国有着广泛的分布与应用,多用于名贵中药材和观赏植物,具有较高的经济价值。由于苛刻的生长条件加上过度的开发利用,导致野生石斛资源破坏严重,大部分种类已近枯竭,这也导致市场上出现的石斛种质混杂、真伪鉴定困难等问题亟待解决。石斛属植物遗传多样性的研究和数字指纹图谱的建立,可以为石斛的品种鉴定与分类、良种选择与保护提供理论依据,对保护药用植物生物多样性也具有十分重要的意义。以31种石斛属植物及金石斛(Flickingeria comata)为研究对象,应用SRAP-PCR分子标记技术对其开展遗传多样性分析并构建DNA指纹图谱。结果表明:利用筛选出来的15对引物进行扩增,共扩增出264个位点,其中多态性位点为251个,平均每对引物扩增出16.73个多态性位点,多态比率达95.08%,其中Me2-Em5、Me4-Em3、Me4-Em5、Me7-Em3、Me7-Ee7等5对引物的多态百分率均为100%,这些引物组合对石斛种类的鉴别效率较高;经过计算31种石斛属植物与金石斛间的观测等位基因数(Na)为1.784,有效等位基因数(Ne)为1.430,Nei’s基因多样性指数(H)为0.202,Shannon’s信息指数(I)为0.386,石斛种间存在较高的遗传变异度与丰富的遗传多样性水平;其遗传相似系数的变化范围为0.591~0.851,亲缘关系较近,当遗传相似性系数为0.660时,金石斛单独聚为一类,当遗传相似性系数为0.724时,可将31个石斛属植物进一步分为10组;构建DNA指纹图谱可单独鉴别出31种石斛属植物以及金石斛,为石斛遗传背景分析和快速鉴别石斛种类提供科学依据。  相似文献   

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