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1.
Isatis tinctoria L. was cultivated until the 19th century to produce indigo, a natural blue pigment used principally for dyestuffs. The current
search for alternative crops and interest in natural products has led to reconsidering I. tinctoria as a crop to be grown in marginal areas to produce natural indigo. To reintroduce I. tinctoria into cultivation, its behaviour under different climatic conditions as well as its morpho-physiological and genetic diversity
must be assessed in order to evaluate the possibilities of future breeding work. To do this, a Eurasian collection of 15 accessions
was studied in a 2-year experiment. The study was carried out in four locations in order to assess plant performance at altitudes
ranging from 380 to 1,700 m a.s.l. A second experiment evaluated the morpho-physiological diversity of several traits (some
related to agronomic performances) of the collection. In a third experiment the genetic traits of the collection were characterised
by using eight AFLP and eight SAMPL markers. The species showed a wide adaptability to different mountainous conditions and
the populations showed high morphologic and genetic variability and differed according to their origins. Both morpho-physiological
and molecular characterisation allowed the accessions to be distinguished into groups of European and Asian origin. Future
breeding work is recommended because some accessions have good agronomic potential.
相似文献
| Valeria NegriEmail: |
2.
Solanum gourlayi and Solanum spegazzinii, wild potatoes endemic to Argentina, possess desirable traits for breeding. In periodical regenerations of accessions, variability
was detected for morphology and breeding barriers. The persistence of these populations in nature was evaluated after more
than 20 years. Both species were observed in all visited sites, along with other wild and cultivated potatoes. Chromosome
numbers coincided with the originally reported, except for one population of Solanum gourlayi, with diploid and tetraploid cytotypes. The accompanying flora and environmental conditions revealed important alterations
as the result of road construction, excessive stocking rates and overgrazing. Principal coordinate and cluster analyses and
an AMOVA using AFLP data of three original accessions and the corresponding new accessions revealed high molecular variability
and extensive overlapping. Plant grouping of accessions occurred at a distance of 0.58 for S. gourlayi, 0.62 for S. spegazzinii and 0.67 for both species. The role of natural hybridization and sexual polyploidization in the evolution of sympatric populations
of wild potatoes is discussed.
相似文献
| Elsa L. CamadroEmail: |
3.
The standardization of environments (E) encouraged by modern society and by the productivist model of agriculture has resulted
in the standardization of genotypes (G) thereby reducing G × E interaction. New societal values call for the diversification
of agriculture to fit contrasted environments. This process can be depicted by four models defined by two axes, one socio-economic
(individual logics versus collective governance), and the other agro-ecological (reductionist versus systemic approaches).
These models differ in (i) their objectives (from improvement in yield to the empowerment of farmers), (ii) their specific
expectations with respect to genotypes (from inherited genetic resources to varieties that represent genetic, ethical and
social progress), (iii) their specific representations of the environment (E) (from a simple interaction between the bio-physical
environment (B) and the crop management (C), to a complex interaction including the competences of the actors (A), outlets
(O), regulations (R), society (S)), (iv) their particular relations between G and E (from G × E to G × B × C × A under evolving
constraints represented by R × O × S). Taking this diversity into account changes the way plant improvement is considered.
Thus, depending on the model, the order, interest and status of the five classic stages of plant improvement (setting objectives,
creating variability, selecting, evaluating and disseminating) may be called into question. Between the existing analytical
model (Model I) and a holistic model (Model IV) which remains to be developed, lies the challenge of ensuring the sustainability,
efficiency and acceptability of plant breeding and resulting innovations. From a simple “statistical parameter” that we, as
plant breeders, attempt to reduce, the G × E interaction is becoming an “objective” that we try to predict and valorize. Structuring
the different components of E, G and G × E, enables us to extend the basic concept of representivity to both the cultivation
conditions and the relational socio-economic positions of the actors involved.
相似文献
| D. DesclauxEmail: |
4.
In maize (Zea mays L.) breeding programs, selection among and within segregating progenies is based mainly on indirect selection criteria. A
better understanding of the environment influence on physiological attributes of maize inbred lines is important to the identification
and selection of superior inbred lines as well as to successful hybrid seed production. In this study, the size and form of
genotype (G) and genotype × environment (G × E) interaction effects for plant grain yield (PGY) and several physiological
attributes were examined for 12 maize inbred lines grown in four managed environments, represented by two seasons (Y) and
two nitrogen levels. Mixed model analysis revealed that the G effect was relatively high for attributes related to light capture,
phenology, early biomass production, and numerical components of PGY. The G × E interaction effect explained most of the variability
for PGY, harvest index (HI), and biomass production at maturity. Three-mode principal component analysis allowed us to: (1)
describe the associations among multiple attributes across environments, (2) reveal the form of the main patterns of G × E
interaction, (3) establish the importance of the genotype × year (G × Y) interaction for kernel number, HI, and biomass at
maturity in determining PGY, (4) identify promising genotypes of high-PGY across environments, and (5) detect genotypes of
similar response patterns for PGY but with a contrasting relative behavior for other attributes, which may permit the simultaneous
selection for grain yield and desired secondary traits. Such selection results would contribute greatly in the identification
of superior inbreds than selecting for grain yield alone.
相似文献
| Karina E. D’AndreaEmail: |
5.
Summary Conventional mutation techniques have often been used to improve yield, quality, disease and pest resistance in crops, or to increase the attractiveness of flowers and ornamental plants. More than 1700 mutant varieties involving 154 plant species have been officially released. In some economically important crops, e.g. barley, durum wheat and cotton, mutant varieties occupy the majority of cultivated areas in many countries. Mutation techniques have become one of the major tools in the breeding of ornamentals such as alstroemeria, begonia, chrysanthemum, carnation, dahlia and streptocarpus. The use of in vitro techniques such as anther culture, shoot organogenesis, somatic embryogenesis and protoplast fusion can overcome some of the limitations in the application of mutation techniques in both seed and vegetatively propagated crops. In vitro culture in combination with induced mutations can speed up breeding programmes, from the generation of variability, through selection, to multiplication of the desired genotypes. The expression of induced mutations in the pure homozygote obtained through microspore, anther or ovary culture, can enhance the rapid recovery of the desired traits. In some vegetatively propagated species, mutations in combination with in vitro culture technique, may be the only method of improving an existing cultivar. Currently, many molecular studies rely on the induction and identification of mutants in model species for construction and subsequent saturation of genetic maps, understanding of developmental genetics and elucidation of biochemical pathways. Once identified and isolated, the genes that encode agronomically-important features can be either introduced directly into crop plants or used as probes to search for similar genes in crop species. It seems most likely that the recent developments based on these technologies will soon provide improved methods for selection of desired mutants. 相似文献
6.
Evolution was measured over 16 years in a self-regenerating, bulk-hybrid subterranean clover population, consisting of F
2 seed from 253 crosses, sown at Nabawa and Mt Barker, short and long growing season sites, respectively, in south-western
Australia. Seed bank samples harvested annually were grown in a common garden. Experiment 1 measured flowering time in plants
from each year, while Experiment 2 measured 26 variables in the populations 3 and 16 years after sowing, in comparison with
the ancestral population. Changes in population means were observed in 20 characters and variability declined in 11 characters
at one or both sites, with much of this occurring within the first three years. Natural selection at Nabawa favoured early
flowering of long duration, thick peduncles, high harvest index and high hardseededness. At Mt Barker it favoured late flowering
of short duration, large leaves and long, thick petioles at flowering, thick stems with long internodes, long, thin peduncles
with a high burial angle, large plants at maturity, low hardseededness and high biochanin A and total isoflavone contents.
High seed production capacity, with high seed weight and seeds per burr, was important at both sites. The use of bulk-hybrid
populations is demonstrated as a low-input means of breeding and selecting well-adapted subterranean clovers.
相似文献
| P. G. H. NicholsEmail: |
7.
J. C. Zadoks 《Euphytica》1959,8(2):104-116
New physiologic races can be produced by mutation, hybridization or heterokaryosis. The genetics of the host parasite relationship can be explained on the basis of the gene-for-gene hypothesis of Flor. Resistance breeding is an important agent in the appearance of a new race and in the evolution of pathogenicity. In America the resistance breeding in wheat is conducted along the following lines:
- 1.Searching for sources of resistance by testing collections of varieties and hybrids. 相似文献
8.
Aurélie Lécolier Pascale Besse André Charrier Thierry-Nicolas Tchakaloff Michel Noirot 《Euphytica》2009,168(1):1-10
Coffee is one of the main products on the international markets, in association with oil, corn, sugar, and paper pulp. The
history of coffee-tree cultivation is incompletely documented, both regarding its domestication in Africa, and its assisted
dispersal throughout the world. This review focuses on the coffee mutant, Coffea arabica ‘Laurina’ (Chevalier A in Encyclopedie Biologique. Vol 28, 1947), also named ‘Bourbon pointu’. This plant is generally acknowledged
to have been selected in the island of ‘Bourbon’ (La Réunion) from a field at the beginning of the 19th century. Compared
with the common ‘Bourbon’ variety, ‘Bourbon pointu’ trees are dwarf, with a characteristic Christmas-tree shape and the beans
have an excellent cup quality. Although cited many times in literature, the origin of this variety is ambiguous and is largely
discussed even today with increasing confusion, particularly in books and local newsletters. This article provides a thorough
historical and bibliographical review of coffee cultivation in La Réunion, which leads to an understanding of the bottleneck
responsible for the low genetic diversity of the ‘Bourbon’-type modern varieties. Complemented by a review of the scientific
studies conducted on this subject, confirmation of the veracity of the various historical accounts becomes possible, and appropriate
conclusions on the origin of the ‘Bourbon pointu’ are derived. Although historical texts provide important information and
represent priceless resources that give direction to scientific research, it is clear that this same research makes it possible,
in turn, to clarify and to interpret historical texts.
相似文献
| Michel NoirotEmail: |
9.
Summary The performance of transgenic varieties depends not only upon the stable and correctly-regulated expression of specific transgenes but also upon the agronomic potential of the background genotype. Ideally, transgenes should be introduced into agronomically-superior cultivars and transgenic varieties will become out-classed if their agronomic properties are not continually improved. It will often prove desirable to use conventional breeding techniques, as opposed to new cycles of transformation, to carry out this process of varietal improvement.Continuing advances in marker-assisted selection have made possible the selection and manipulation of an entire genetic background. This means that transgenes can be transferred to new and often untransformable varieties with relative ease. To carry out this process efficiently requires the correct choice of male and female parents, the use of appropriate marker-systems and the concentration of selection on the most appropriate generations.Efficient, phenotypically-neutral marker-systems have revolutionised the identification and manipulation of quantitative trait loci (QTLs). The loci which modify the expression of transgenes are a form of QTL. Desirable alleles at modifier QTLs can be transferred to new varieties along with the transgenes themselves, using marker-assisted breeding.The strategies for maker-assisted selection are becoming ever more sophisticated. A range of complementary marker systems allows the selection of desirable genotypes. In addition, the meiotic reassortment and recombination of chromosomes which produces new genotypes is becoming better understood. The most efficient plant breeding methods and the most powerful genetics will make optimal use of both markers and meiosis. 相似文献
10.
Emilly Ruas Alkimim Eveline Teixeira Caixeta Tiago Vieira Sousa Felipe Lopes da Silva Ney Sussumu Sakiyama Laércio Zambolim 《Euphytica》2018,214(3):50
The use of molecular markers to detect polymorphism at DNA level is one of the most significant developments in molecular biology techniques. With the development of new next-generation sequencing technologies, the discovery of SNP became easier and faster, and the costs of data point were reduced. The development and use of SNP markers for coffee have provided new perspectives for the evaluation of genetic diversity and population structure via different statistical approaches. In this study, 72 Coffea canephora genotypes were analyzed to identify the SNP markers and apply them to genetic studies and selection of parents/hybrids in genetic breeding. As many as 117,450 SNP were identified using the RAPiD Genomics platform. After quality analyses, 33,485 SNP were validated for analyses of genetic diversity and population structure. Genotypes were separated based on their varietal groups, and Hybrids were differentiated using the clustering and Bayesian approach. Coffee accessions mistakenly identified in the germplasm and breeding program were detected. The Conilon varietal group presented the lowest genetic dissimilarity values, suggesting the introduction of new accessions in the germplasm bank. The highest genetic distances values were observed among genotypes of the heterotic groups (Conilon and Robusta). The markers were efficient in evaluating the genetic diversity and population structure of C. canephora. Promising crosses were selected within and between the varietal groups. Hybrids with greater genetic distances were selected, which were important for C. canephora breeding programs. 相似文献
11.
Balakrishnan Divya S. Robin R. Rabindran S. Senthil M. Raveendran A. John Joel 《Euphytica》2014,200(1):61-77
Marker assisted backcrossing breeding has become one of the essential tools in transferring novel genes to adapted varieties and was employed to pyramid three blast resistance genes Pi1, Pi2 and Pi33 to a popular susceptible rice variety ADT43. Gene pyramiding process was facilitated by marker aided selection for both foreground as well as background genotype. Previously reported linked molecular markers were deployed to survey resistant and susceptible genotypes. In the BC3F1 generation four lines viz, AC-B3-11-7, AC-B3-11-36, AC-B3-11-57, AC-B3-11-83 were identified to be pyramided with three genes and subjected to background analysis and a genome recovery up to 95 % was observed and advanced to further generations. Morphological, yield and grain quality traits were significantly similar to ADT43. The introgressed lines with three gene combinations were highly resistant to the blast pathogen compared to genotypes with single genes and the susceptible checks under blast nursery screening at two epiphytotic locations; Coimbatore and Gudalur. The selected three gene pyramided backcross lines in the desirable background were advanced to obtain an improved ADT 43 with resistance to blast disease. 相似文献
12.
K. Ter Horst 《Euphytica》1961,10(3):277-282
The selection of pulses in Suriname can be distinguished according as the objective is aiming at breeding for sandy soils or for heavy clay soils. The selection for sandy soils is mainly related to groundnuts for local consumption. This article deals with selection for heavy clay soils where pulses are grown in rotation with rice and are destined mainly for the world market. The crops are soybeans, cowpeas, blackeye peas, mungbeans and some other, minor crops. The existing local varieties were partly superseded by varieties from Indonesia or the Philippines, partly by lines selected from local varieties. The results of the investigations led to the following conclusions.
- 1.Any country wishing to raise varieties that surpass its own local varicties can start with simple line selection. 相似文献
13.
Maw Sun Lin 《Euphytica》1991,56(1):43-46
Summary The pedigrees of 99 Japonica rice (Oryza sativa L.) varieties released between 1940 and 1987 were traced back to 65 ancestors, of which 44 were plant introductions from Japan and only 11 from Taiwan. Japanese introductions collectively contributed more than 85% of the parentage of the varieties. Although more ancestors were integrated into recent breeding programs, as few as 10 ancestors comprised 66% of the genetic background. Extensive use of superior genotypes from the same sources explained why the integration of new germplasm did not result in the diversification of the released varieties. The 10 most important ancestral contributors of the 99 varieties were from Japan except Oloan-chu from Taiwan. Two introductions, Sinriki and Kameji, had the highest mean relative genetic contributions of the genes with 21.3% and 16.7%, respectively. Shinriki was the most frequently used ancestor and occurred in 83 of the 99 pedigrees. These results clearly revealed the narrow genetic base in current Japonica rice varieties of Taiwan. 相似文献
14.
M. J. Carena 《Euphytica》2013,191(2):165-171
Maize (Zea mays L.) breeding programs integrating pre-breeding with cultivar development are needed. The objectives of the North Dakota corn breeding program are to adapt exotic and unique germplasm, maximize the genetic improvement of adapted germplasm, and develop unique short-season products for breeding and commercial use. This applied program has significant support from state maize grower organizations, farmers, food and fuel processors, and industry. As a result 25 inbred lines and 17 improved populations, carrying unique alleles not present in the B73 line and the Nested Association Mapping population (NAM) genomes, were released in the past 10 years and six hybrids were identified for commercial purposes. These included the first releases from our NDSU EarlyGEM program to increase the genetic diversity of U.S. northern hybrids and break environmental margins. These are not registered nationally due to exclusive agreements with industry. The strategic location of this research program allows the exploitation of challenging environmental conditions making evolution toward desirable goals faster, discarding unstable and weak maize varieties effectively. There are still several challenges to be addressed though. Retailer companies offer fewer products with more events making maize more vulnerable due to similar genetics. The confidential nature of the maize business limits breeding rights to develop better industry products, which currently reduces the breeding efficiency to identify the most outstanding hybrids for farmers across regions. Maize research, development, and production in marginal regions can be uniquely positioned to lead breeding research for climate changes and the development of the next generation of genetically broad-based elite products. Improvements in intellectual property and re-thinking of breeding rights access are encouraged. 相似文献
15.
Summary In the early days of bulb breeding, plants were selected for their beauty-rarely a joy for ever, since fashion changed and new varieties supplanted their ancestors. Beauty has remained the first requirement to the present day. However, physiological characters such as easy propagation, good growth, and suitability for early forcing, are almost as important at present. The merits of a plant for garden decoration take third place.The number of varieties that can meet these requirements is very small; but since the demand is for the best in great quantities, this small group accounts for the greater proportion of all bulbs grown, as demonstrated by the statistical data. It will be very difficult to surpass these varieties, or even to make additions to this group.In hyacinths and daffodils it is even more difficult to develop breeding schemes, as the leading varieties are mostly heteroploids and polyploids, respectively. Here a breeder's intuition is needed above all things to bring us better varieties. 相似文献
16.
Summary The anthocyanins in outer perianths of seven varieties and one telotrisomic line of Japanese garden iris, Iris ensata Thunb., were analysed by high-performance liquid chromatography procedures. Two new anthocyanins, peonidin 3RGac5G and cyanidin 3RGac5G were putatively detected in this species, and peonidin 3RGac5G was the major anthocyanin for all the varieties except Telotri-1 and cyanidin 3RGac5G the major anthocyanin for Telotri-1. Moreover, cyanidin 3RGac5G and peonidin 3RGac5G are useful anthocyanins for the breeding of red and magenta flowers. Finally, the breeding strategy for new flower varieties using cyanidin 3RGac5G and peonidin 3RGac5G was discussed.Contribution from the Laboratory of Plant Breeding, Faculty of Agriculture, Miyazaki University, Japan, No. 84. 相似文献
17.
J. C. Dorst 《Euphytica》1958,7(1):9-20
In the Dutch List of Varieties of 25 years ago many varieties occurred which are no longer grown now. By a change-over from the use of line-selection in local varieties to the application of artificial crossing, much progress was made in self-fertilizing plants (wheat, barley, oats, flax, etc.).Great improvements were also attained in the field of grasses. Many new grass strains from Dutch breeders now figure in the List.By paying more attention to disease resistance a number of resistant varieties have been obtained and important vistas have been opened. Increasingly and on a much larger scale than 25 years ago, use is made of the gene stock of other countries.In sugar beet, polyploid varieties have come to the fore, while everywhere attempts are being made to raise tetraploid fodder beets. In other crops also the prospects of polyploid varieties are encouraging.In the last 25 years many breeding establishments have been modernized. Many have glasshouses and use them to good advantage in their breeding work.The establishment of the Foundation for Agricultural Plant Breeding (S.V.P.) rendered it possible to pay more attention to extension while private breeders are provided with good parent plants and selected hybrid populations.The Plant Breeder's Decree became a protection of the breeder's property. As a result the number of breeders increased considerably in the last 25 years, especially those in the field of potato breeding.
Adapted from an article in Dutch, published in the Memorial volume Tussen ras en gewas (Amidst crops and varieties) of the N.A.K. (3). 相似文献
Adapted from an article in Dutch, published in the Memorial volume Tussen ras en gewas (Amidst crops and varieties) of the N.A.K. (3). 相似文献
18.
Maize commercial hybrids compared to improved population hybrids for grain yield and agronomic performance 总被引：1，自引：0，他引：1
Improved maize (Zea mays L.) populations and population hybrids can both be profitable alternatives to commercial single-cross hybrids as well as good elite sources of diverse inbred lines. The objective of this research was to compare grain yield and agronomic performance between early maturing maize population hybrids and current early maturing commercial single-cross hybrids. This is a consequence of our research program targeted at identifying alternative heterotic patterns for the northern Corn Belt. Improved maize populations and population hybrids (S0 generations) were evaluated in experiments arranged in randomized complete block and partially balanced lattice designs across 29 environments. Grain yield potential of population hybrids was optimally expressed under irrigated conditions. Data across environments showed that 20% of the population hybrids evaluated were not different (P 0.05) from at least one of the commercial single-cross hybrids for grain yield performance, root lodging, and stalk lodging percentages. The average mid-parent heterosis value across population hybrids from different geographic regions was 20.4% with negative estimates observed in only two population hybrids. Breeding efforts toward elite populations and population hybrids have demonstrated that germplasm improvement is extremely valuable and deserves public funding. These efforts should be supported in order to enable the development of elite sources of diverse inbred lines and the development of improved population hybrids for specific markets (e.g., organic) to increase producer options. Public maize breeding programs utilizing recurrent selection methods for germplasm improvement could address the need. These programs, however, should incorporate extensive testing of population hybrids. 相似文献
19.
M. Nieuwhof 《Euphytica》1963,12(2):189-197
- 1.From 1958 to 1962 research was carried out on the breeding of hybrid varieties of pointed-headed cabbage. 相似文献
20.
A. Gallais 《Euphytica》1988,39(2):95-104
Summary To discuss the utilisation of heterosis in plant breeding it is necessary to consider its genetic basis. In cross fertilized plants in which the phenomenon of heterosis is very important, such as maize, it appears that a great part can be explained by the mutation load. However in both autogamous or allogamous plants it is difficult to exclude a role of marginal overdominance which could justify hybrid variety production.To know in a relatively short time whether it will be better to develop lines or hybrids it is necessary to know the parameters (mean and variance) of the distribution of all varieties of a given type which can be derived from the breeding population. A numerical application allows the determination of the situations where the best single crosses will be better than the best lines. With some approximate values of the necessary parameters, the case of grain yield in maize and in wheat is briefly discussed.To develop lines or hybrids, a general strategy is given. Its main axis is population improvement which has to be adapted to the type of varieties to develop. It is shown that according to the situation the type of varieties to develop can change with time: single crosses can be more justified at the beginning and lines can be justified later if all heterosis were fixable. To develop hybrids the best scheme is reciprocal recurrent selection with half-sib or full-sib progenies followed by pedigree reciprocal selection initiated by full-sib progeny tests. With this strategy there is no problem of the prediction of hybrid performances. However it seems possible to develop some predictors of heterosis or of specific combining ability between two lines using some criteria of genetic distances. Preliminary results with distances computed from the behaviour of lines in a two-tester top cross design appears very stimulating.Communication given at the206th meeting of teh Genetical Society of Grain Britain 相似文献