The objectives of this study were to investigate: (1) the effects of genotype, environment, and their interactions on the oil content (OC), protein content (PC) and grain yield (GY) of 25 varieties of winter wheat, (2) the correlations among these traits in different environments, and (3) the effects of different climatic variables and their interactions with wheat genotypes for the examined traits. The field experiments were performed on three experimental sites in Serbia in 2009/10 and 2010/11. The most variable traits were GY and PC, while the variations of OC were lower. A significant positive correlation between wheat bran OC and GY was found in one, while highly significant negative correlations between PC and GY were found in three out of six environments. The partial least square regression (PLSR) triplots for protein content, oil content and grain yield enabled us to identify favorable and limiting climatic conditions for each trait and explained 31.9%, 32.6%, and 30.4% of the total variance, respectively. Cvs. Renesansa and Zvezdana were identified as genotypes with high average values for all traits, while cvs. Bankuty 1205 and Banatka were identified as potential sources of high protein content.
25 April 2014 in The Journal of Agricultural Science
SUMMARY: Improving resistance to water and osmotic stresses at the seedling stage is becoming a much more important target for wheat breeders due to an increase in the frequency and severity of drought occurrences at the crop establishment and tillering phases in many wheat growing areas of the world. Ninety-six diverse wheat genotypes were laboratory tested for germination and growth response under osmotic stress induced by polyethylene glycol (PEG). Germination percentage, mean germination time, coleoptile length, shoot length and shoot growth rate were compared under stress (−0·4 MPa) and control (0·0 MPa) conditions. The same genotypes were previously grown in field trials exposed to drought stress during the anthesis and/or grain filling growth stage along with control (optimum) conditions. Grain yield (GY) and 19 other traits of agronomic importance (earliness, stem-related traits, number of kernels, mass of 1000 grains, etc.) were recorded. All seedling traits under PEG-induced water stress showed the highest relationship with the stem and stem-related traits of adult plants. To study the correlation between stress tolerance in the seedling and reproductive stages, three stress indices (tolerance index (TOL), stress susceptibility index (SSI) and stress tolerance index (STI)) for the seedling traits and GY under pre- and post-anthesis drought stress were calculated, based on a mean trait value obtained under stress and the corresponding trait value under control conditions. The ranking of the genotypes based on TOL and STI from seedling traits was found in most cases to be significantly correlated with the ranking of genotypes based on TOL and STI from GY, respectively.
16 November 2017 in The Journal of Agricultural Science
SUMMARY: Knowledge of genetic diversity of confectionary sunflower can have a large impact on its use in breeding programmes. However, levels and distribution of genetic variation within the confectionary sunflower gene pool are still not adequately explored. The aim of the present paper was to describe the diversity of 68 confectionary sunflower genotypes: open-pollinated varieties, lines and hybrids. A total of 32 morphological traits were used for characterization. The Shannon & Weaver diversity index (H) was estimated as a measure of morphological diversity. The mean value of the Shannon index was 0·71, which indicates a high morphological diversity. The lowest diversity was found for leaf descriptors, moderately high to high for seed traits, while the highest values were found for disc flowers and ray florets. The highest individual descriptor diversity was found for: head attitude, the angle of leaf lateral nerves and ray floret disposition. The homogeneity analysis (HOMALS) multivariate reduction technique for nominal categorical data proved to be an efficient method for a comprehensive overview of genotype diversity and group homogeneity. Besides diversity, the number of categories and uniformity of genotype distribution determines discriminative power of descriptors. Traits that contributed the most to the distinction of genotypes were identified, enabling differentiation of genotypes with similar phenotypic attributes. The highest discriminative power was observed in traits such as anthocyanin colouration of stigma (DFIA), seed colour of stripes and seed main colour. The genotypes tested formed two distinctive major groups of varieties and hybrids with inbred lines widely dispersed along both axes. A separate grouping was obtained per the most discriminative traits based on HOMALS analysis, while the best separation was obtained using DFIA. Isolated genotypes that may not be representative by yield or seed-specific traits can be useful sources of traits for breeding. Morphological characterization can be used to improve description and classification of confectionary sunflower germplasm when evaluating diversity.
Red clover (Trifolium pratense L.) is one of the main forage species from temperate regions and it's originated in Eurasia where wild-type populations are found in the Caucasus Mountains. Considerable variation for this crop has been recorded for few molecular variations. The identification and understanding of molecular genetic diversity in red clover accessions will help in effective genetic conservation along with efficient breeding programs in this crop. This study has shown molecular diversity using microsatellite markers in red clover accessions from around of the world. In this investigation, 40 genotypes have been selected and analyzed using 15 SSR primers. These primer pairs amplified 1146 polymorphic loci among the genotypes screened. The number of fragments amplified by each SSR primer combination varied from 24 for RCS3681 to 109 for RCS1729 with an average value of 80.78 per primer combination. The SSR marker data was further analyzed using cluster algorithms and Principal coordinates analysis (PCoA). The results indicated that the considerable genetic variations were discovered among the analyzed genotypes. The SSR based clustering could identify the putative pedigree types of the present red clover types of diverse origins.
6 July 2020 in Genetic Resources and Crop Evolution