Добірка наукової літератури з теми "Morpho-Phenological diversity"

Durum wheat (Triticum durum Desf.) is a strategic culture in Algeria. Characterization and evaluation of crop varieties allow backup and restoration of this genetic heritage and its use in breeding programs. In this context, the study is subject to the identification of some morpho - phenological parameters and molecular markers in kind RAPD variability of 20 genotypes of collection of Algerian durum wheat (Triticum durum Desf.) Belong to two varieties (rechenbachi and leucomelan). The results of the morpho-phenological and genetic analysis show substantial phenotypic diversity between varieties. RAPD marker showed an intervarietal genetic polymorphism.

SUMMARYBrachypodium hybridum belongs to the Poaceae grass subfamily. It has a close genetic relationship with temperate cereal crops, which means that it can be used as a model for temperate cereal and grass crops. In order to improve knowledge on the genetic diversity of this species, 145 lines of B. hybridum representative of nine populations and all the ecoregions of Tunisia were characterized on the basis of 18 morpho-phenologic features. The results show a considerable variation between populations and ecoregions in all traits studied. Variation was relatively higher for reproductive than vegetative traits. The majority of traits showed very low to high heritability with low border value for average length of spikelet (ALS) and an average value of 0·64. It is noticeable that high values of heritability were observed for most vegetative descriptors, with low values for reproductive ones. Differentiation between populations (QST) varied from 0·02 for ALS to 0·78 for average length of leaves with a mean value across traits of 0·4, which confirms the wide intra-population variation in Tunisian natural population of B. hybridum. Pairwise QST showed that the greatest differentiation among populations was registered between Ain Drahem and Jbel Zaghouan and the smallest between Haouria and Raoued. Overall, the Ain Draham population showed the largest differentiation from the rest of the populations. To infer the effect of geographic distribution of the species, a Mantel test was applied between observed pairwise differentiation and geographic distance between populations and between ecoregions: the results show a positive, but not significant, relationship. In addition a significant negative relationship was found between phenotypic diversity and altitude, indicating that genetic diversity decreased with increasing altitude. Taken together, the high levels of intra-population variation and the lack of correlation between genetic differentiation and geographic distribution suggest a potentially important rate of long-distance seed dispersal and confirm the role played by natural selection in the population structure of Tunisian natural populations of B. hybridum.

Legumes’ cultivation contributes services to agro-ecosystems and society, in line with the principles of sustainability. Among pulses, the common bean is one of the most important sources of plant proteins and other important nutrients for humans. Extensive phenotypic and genetic characterisations of unexplored bean germplasm are still needed to unlock its breeding potential. To the purpose, a panel of 192 diverse genotypes, mainly developed starting from European landrace accessions, was characterised for relevant morpho-phenological traits; a partially replicated experimental design was used. For each quantitative trait, Best Linear Unbiased Predictors and broad-sense heritability were estimated. The screened panel revealed a high level of diversity for most of the measured traits, especially for days to flowering and hundred-seed weight. The same material was also characterised by means of double-digest Restriction-site Associated DNA; a high number of SNP markers were successfully produced. The genotyping allowed understanding the fine genetic structure of the panel. Genetic information was also used to study morpho-phenological traits considering different genetic groups existing within the panel. At the same time, genotypes characterised by favourable traits were identified. The availability of such collection with its extensive characterisation, make this material an excellent resource for common bean improvement.

Knowledge of the genetic diversity is important to design appropriate selection criteria in the breeding programs. In this study, the genetic diversity of 42 Iranian and European barley cultivars was investigated with morpho-agronomic traits including phenological, physiological, morphological traits, grain yield and associated traits. Analysis of variance showed high variability among cultivars. The European cultivars Panaka, Aiace and Pariglia had the highest grain yield. The results of group comparisons indicated that the European cultivars produced higher grain yield (500.57 g/m2) than the Iranian cultivars (445.50 g/m2), but larger genetic diversity based on morpho-agronomic traits was observed among Iranian cultivars than European cultivars. Correlation analysis revealed the high significant correlations between grain yield with biological yield (0.92), straw yield (0.77), and number of spike per square meter (0.67). Based on the factor analysis, the six factors that justified 81.63 percent of the variations were identified. The first factor having the largest eigenvalue was identified as effective factor on the vegetative and reproductive growth. In path analysis, biological yield had the greatest effect on grain yield (0.906). Cluster analysis classified the cultivars in six groups and showed that genetic variation based on the all studied traits among the barley cultivars was not related to geographical location.

AbstractSunflower (Helianthus annuus L.) is used as “seed snacks”, so called “pipas”, in the Mediterranean countries which may offer an interesting opportunity for agricultural diversification of this crop. The morpho-phenological variability already demonstrated in the Tunisian local populations can be a basis for the creation of new varieties well adapted to climate and soil conditions in that region. The molecular characterization of 59 accessions and reference lines generated 194 alleles from 30 SSR loci (3–10 alleles per locus) and 54 haplotypes, built from 117 SNP detected by NGS sequencing of 7 genes (4–16 haplotypes per gene). These data highlight some uniqueness of the Tunisian material compared to 7 control lines but a low genetic dispersion between accessions. However, a core collection of 8 populations, capturing 88 % of the Tunisian genetic diversity, could be proposed for a future sunflower breeding program.

This endeavor includes thirty grapes’ genotypes grown in northern zones of Punjab, Pakistan to determine similarities and dissimilarities in forty-four morphological traits according to the descriptor “International Plant Genetic Resources Institute (IPGRI)”. The relation between the genotypes was determined by principal component analysis (PCA), and similarity was worked out by using cluster analysis. The dendrogram divided the genotypes into two main groups with classes and subclasses. The variation present within the class was up to 81.72% while the difference between classes was 18.28%. The morphological quantitative traits such as bunch length, bunch width, bunch weight, peduncle length, the weight of 10 berries, number of berry in a bunch, berry length, and berry width were in the following range 27.50-11 cm, 13.75-5 cm, 583.56-77.70 g, 6.50-1.55 cm, 53.70-9.70 g, 354-28, 27.37-11.40 mm and 18.06-10.41 mm respectively, which indicated a wide level of diversity in the selected genotypes. Based on phenological attributes, “Regina”, “Perlet”, and “Early White” were found early maturing genotypes to prevent berry rotting due to monsoon rains at the final stage of ripening. The data generated in this study would be helpful to preserve the existing germplasm and be available for designing future breeding programs.

Deux genres voisins Coffea et Psilanthus incluant 141 espèces sont à l’origine des caféiers dont seulement deux (C. arabica et C. canephora) sont cultivées. Une meilleure connaissance de la diversité et de l’évolution des espèces sauvages peut permettre d’optimiser la sélection.Au niveau morpho-phénologique, les caféiers Malgaches montrent une grande diversité des caractères comme la longueur du cycle de maturation des fruits qui varie de 3 à 12 mois en fonction de leur distribution écologique.Au niveau évolutif, deux types de chloroplastes, Coffea et Psilanthus, ont été identifiés au sein du genre Coffea. Ils sont probablement transmis par des mécanismes tels que la rétention de polymorphismes ancestraux dus à un tri incomplet des lignées ou l'hybridation interspécifique suivie d’homoploïdie.Les caféiers montrent une diversité de la présence de la caféine. Produit par les caféiers cultivés et la majorité des espèces africaines, la caféine est absente des espèces des îles de l’océan indien. Chez C. humblotiana, nous avons démontrer que l’absence de la caféine est liée à l’absence d’une région de 76 Kb portant le gène de la caféine synthase (DXMT). Finalement nous avons démontrer que les hybrides Ratelo tétraploïdes interspécifiques entre C. arabica et des espèces sauvages diploïdes peuvent suppléer la culture de l’Arabica qui est mal adaptée aux conditions pédoclimatiques de Madagascar.Ensemble, ces différentes études permettent de comprendre le genre Coffea et de commencer à utiliser ces ressources génétiques en amélioration face aux défis comme la tolérance à la rouille, le changement climatique et la demande des consommateurs pour des cafés avec des signatures organoleptiques exceptionnelles
Two related genus Coffea and Psilanthus including 141 species are at the origin of Coffea classification, which only two (C. arabica and C. canephora) are cultivated. More knowledge of the diversity and evolution of wild species can help to optimize the selection.At the phenological level, Madagascan coffee trees show a great diversity of characters such as the length of the fruit ripening cycle, which varies from 3 to 12 months depending on their ecological distribution.At the evolutionary level, two types of chloroplasts, Coffea and Psilanthus, have been identified within the genus Coffea. They are probably transmitted by mechanisms such as retention of ancestral polymorphisms due to incomplete lineage sorting or interspecific hybridization leading to homoploidy.Coffea species show a diversity of the presence of caffeine. Produced by cultivated coffee trees and the majority of African species, caffeine is absent from species from the Indian Ocean islands. In C. humblotiana, we recently found that the absence of caffeine is linked to the absence of a 76 Kb region carrying the caffeine synthase (DXMT) gene.Finally, we discovered that the interspecific Ratelo tetraploid hybrids between C. arabica and diploid wild species could supplement the Arabica cultivation, which is poorly adapted to the pedoclimatic conditions of Madagascar.All these different studies make it possible to understand the Coffea genus and to start using these genetic resources for breeding facing the challenges such as rust tolerance, climate change and consumer demand for coffees with exceptional organoleptic signatures