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101.
Transposable elements are presents in all known genomes so far, and have the faculty of changing their genomic location and/or number of copies within the genome. They are mobile endogenous genetic elements, with a large variety of structure and transposition mechanism. In crops, they compose the major part of the nucleic DNA, up to 80% in some cereals like maize and wheat. Despite their omnipresence, they are largely unknown and uncharacterized within the Poaceae family. In this review, we describe a possible classification of the elements present in this family, some of their known transposition mechanism, their known activity and possible action in crops, and their possible origin. 相似文献
102.
103.
Eveline Teixeira Caixeta Aluízio Borém Samir de Azevedo Fagundes Silvia Niestche Everaldo Gonçalves de Barros Maurílio Alves Moreira 《Euphytica》2003,134(3):297-303
The existence of genetic variability for angular leaf spot (ALS) resistance in the common bean germplasm allows the development
of breeding lines resistant to this disease. The BAT 332 line is an important resistance source to common bean ALS. In this
work we determined the inheritance pattern and identified RAPD markers linked to a resistance gene present in BAT 332. Populations
F1, F2,BCs and BCr derived from crosses between BAT 332 and cultivar Rudá were used. Rudá is a commercial cultivar with carioca
type grains and susceptible to ALS. The resistance of BAT 332 to race 61.41 of the pathogen was confirmed. Segregation analysis
of the plants indicated that a single dominant gene confers resistance. For identification of RAPD markers linked to the resistance
gene, bulk segregant analysis (BSA) was used. Two RAPD markers,OPAA07950 and OPAO12950, linked in coupling phase at 5.10 and 5.83 cM of this gene, respectively, were identified. These molecular markers are important
for common bean breeders and geneticists as source of genetic information and for marker assisted selection in breeding programs.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
104.
Claude Bakoumé Benjamin Adon Benoît Cochard Françoise Potier Tristan Durand-Gasselin Philippe Amblard 《Euphytica》2001,121(1):59-64
Following a survey involving wild oil palm groves in Côte d’Ivoire as a whole in 1968, 17 parents were chosen at Yocoboué (southernCôte d’Ivoire). Agronomic performance of the 17 parents was assessed through Deli × Yocoboué hybrids in 3 trials grown at La Mé (Côte d’Ivoire), Mondoni and La Dibamba (Cameroon).When compared to the Deli × La Mé progenies used as controls, the Deli × Yocoboué hybrids produced 91% for total bunch weight and86% for oil yields. However, the genetic variability within the Deli × Yocoboué progenies allows to select individual progenies as productive as the Deli × La Mé controls, for breeding purposes. A study of major agronomic traits led to the choice of parent YO 11 T , which combines the largest number of favourable traits. On average, Deli × Yocobouéprogenies have slower vertical growth and are susceptible to Fusarium wilt, except 2 parents (YO 3 T and YO 9 T), which seem to be resistant. 相似文献
105.
The female line 1709, carrying the recessivecharacter green cotyledon, marker of the embryogenotype, was cross-pollinated by bees in the presenceof either male line HG115 or male line Dial63. In thecomparison of seeds which resulted either fromintercrossing or from selfing, a xenia effect wasobserved on volume and number of cotyledon cells andon individual seed weight which was dependent on themale line. The increase of hybrid seed weight inducedby the small-seeded male line Dial63 was larger thanthe one induced by the large-seeded male line HG115.The xenia effect on seed weight was correlated withthe level of heterosis in the F1 plant's growth. 相似文献
106.
107.
108.
François Balfourier Jose Alberto Oliveira Gilles Charmet Enrique Arbones 《Euphytica》1997,98(1-2):37-46
A sample of 58 natural ryegrass populations (Lolium perenne L.) from the French and Spanish oceanic coast was evaluated for
three seasonal growth traits (i.e. spring, autumn and winter vigour traits) in 5 evaluation sites (three in France and two
in Spain). This sample showed a high level of genotype (population) × environment (evaluation sites) interactions for the
three agronomic traits. A factor regression analysis, using both isozyme frequencies of populations and climatic factors of
evaluation sites as covariates, was carried out on a sub-sample of 30 populations in order to explain these interactions.
This method succeeded in explaining most population × location interactions by the product of two covariates. For instance,
for spring vigour trait, 72.8% of the interaction term could be explained by the use of two covariates: the PGI2-20 allelic
frequency of populations and the minimum temperature of the coldest month of evaluation sites. This study shows the advantage
of such a method for plant breeders who need to identify promising ryegrass populations for their breeding objectives. A number
of genetic and evolutionary hypotheses are also discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
109.
Ahmet Demirak Ahmet Balci Ömer Dalman Mehmet TÜfekçI 《Water, air, and soil pollution》2005,162(1-4):171-181
In this work, trace metals such as Hg, Pb, As, Cd, Cu, Fe, Mn and Zn in underground water samples obtained from three wells, an ash-pond and drinking water located near the Yatagan Thermal Power Plant were measured. As, Hg, Cu and Zn contents of the underground water were lower than those reported in the EEC (European Economic Community) and WHO (World Health Organization) guidelines. In contrast, the levels of Fe, Pb, Cd and Mn in some groundwater samples were higher than EEC and WHO guideline values. The trace metal concentrations in coal ash-pond water were observed to be lower than water quality standards with the exception of Pb. The obtained results indicated that the trace metal concentration in the sampled drinking water site did not exceed WHO limits. 相似文献
110.
Guyot S Marnet N Sanoner P Drilleau JF 《Journal of agricultural and food chemistry》2003,51(21):6240-6247
Five French cider apple varieties were compared on the basis of their detailed polyphenol profile in the cortex and in the juices. Among the factors studied, variety was the most important variability factor in fruits, whereas polyphenol profiles showed an overall stability from one year to another, and a limited decrease of polyphenol concentration was observed during the starch regression period of fruit maturation. In juices, procyanidins remained the preponderant polyphenol class with concentrations up to 2.4 g/L even in centrifuged juices. Compared to the fruits, the average degree of polymerization of procyanidins was significantly reduced in the juice. Centrifugation of the crude juice had only minor effects on the polyphenol composition. For one variety, highly polymerized procyanidins with average degrees of polymerization of 25 were shown to be soluble in the centrifuged juice at a concentration of close to 1.2 g/L. Oxygenation of the juices during processing resulted in a significant decrease of all classes of native polyphenols. Catechins and procyanidins were particularly affected by oxidation, whereas caffeoylquinic acid was partly preserved. The transfer of polyphenols after pressing was maximal for dihydrochalcones and minimal for procyanidins with extraction yield values close to 80 and 30%, respectively. 相似文献