Diversidade genética em soja baseada em caracteres agronômicos e marcadores microssatélites

Decision letter: Data-driven, participatory characterization of farmer varieties discloses teff breeding potential under current and future climates

In Brazil, pepper cultivation gives producers more marketing opportunities in various segments, either for fresh consumption or industry. Reproductive traits are efficient methods for comparing genetic divergence in pepper, once most differences among accessions could be verified at this stage. This study aimed to evaluate the genetic divergence in the reproductive phase of pepper accessions by multivariate analysis and test the efficiency of different methods. Sixty-five genotypes from the Federal University of UberlândiaCapsicum spp. Germplasm Bank were evaluated 145 days after sowing, and morphological characterization was performed at reproductive phase. Graphical representation of genetic distances was obtained by UPGMA. Tocher optimization method was also used to group accessions. Genotypes were arranged in seventeen different groups by Tocher method. UPGMA dendrogram collaborated with Tocher method, indicating the wide genetic variability of genotypes. Tocher and UPGMA methods were partially in agreement, allowing grouping 44 of the 65 analyzed accessionsequally. Multicategorical traits have the advantage of easy observation and require less time and labor, being ideal for use in gene bank and collections that do not have high human and financial resources. Moreover, these traits are not affected by the environment. Genetic divergence detected in this paper encourages other researchers to perform the characterization of pepper collections as completely as possible, because it becomes possible to generate more reliable information of the variability and genetic divergence among accessions. Our research discloses the reproductive biodiversity of pepper in “Alto Paranaíba” and “TriânguloMineiro” regions and the importance of maintaining these genotypes.

Microsatellite Libraries Enriched for Several Microsatellite Sequences in Plants

The objective of this study was to evaluate the genetic diversity of soybean cultivars by adopting phenotypic traits and enzymatic markers, the relative contribution of agronomic traits to diversity, as well as diversity between the level of technology used in soybean cultivars and genetic breeding programs in which cultivars were inserted. The experiments were conducted on the field at the Center for Scientific and Technological Development in crop-livestock production and the Electrophoresis Laboratory of Lavras Federal University. The agronomic traits adopted were grain yield, plant height, first legume insertion, plant lodging, the mass of one thousand seeds, and days for complete maturation, in which the Euclidean distance, grouped by Tocher and UPGMA criteria, was obtained. After electrophorese gels for enzymatic systems, dehydrogenase alcohol, esterase, superoxide dismutase, and peroxidase were performed. The genetic similarity estimative was also obtained between genotypes by the Jaccard coefficient with subsequent grouping by the UPGMA method. The formation of two groups was shown using phenotypic characters in the genetic diversity study and individually discriminating the cultivar 97R73 RR. The character with the greatest contribution to the genetic divergence was grain yield with contribution higher than 90.0%. To obtain six different groups, individually discriminating the cultivars CG 8166 RR, FPS Jupiter RR, and BRS MG 780 RR, enzymatic markers were used. Cultivars carrying the RR technology presented more divergence than conventional cultivars and IPRO cultivars.

Triticum aestivum L. em. Thell, known as bread wheat, is a vital staple crop globally, contributing significantly to caloric and protein intake. Its hexaploid nature, comprising three genomes (AA, BB, DD), resulted from natural hybridization, enhancing its agricultural significance. The advent of high-yielding cultivars during the Green Revolution drastically increased wheat yields, and its adaptability and self-pollinating characteristics further solidified its importance in food production. Genetic diversity within Triticum aestivum is crucial for improving traits such as stress tolerance and yield. This study highlights the necessity of estimating genetic variability among wheat genotypes, utilizing 24 genotypes. The study assesses the genetic parameters and diversity of various morpho-physiological traits in bread wheat genotypes, focusing on their variability and potential for genetic improvement. Key genetic parameters including the coefficient of variation (CV), genotypic coefficient of variation (GCV), phenotypic coefficient of variation (PCV), and genetic advance as a percentage of mean (GAM) were estimated for traits such as days to heading, plant height, peduncle length, and grain yield. Days to heading exhibited low variability, while plant height showed considerable genetic variation, indicating a good potential for improvement. The wheat genotypes were grouped into five distinct clusters based on Mahalanobis divergence and Tocher's method, revealing significant genetic diversity. Cluster I, comprising eighteen genotypes, displayed the highest intra-cluster distance, while Clusters III and V showed the greatest inter-cluster distance. Trait analysis across clusters highlighted variations in days to heading, plant height, grain yield, and other traits, emphasizing the genetic diversity and potential for selective breeding in wheat.

Sea buckthorn (Hippophae rhamnoides) is an ecologically and economically important species. Here, we assessed the diversity of 78 accessions cultivated in northern China using 8 agronomic characteristics, oil traits (including oil content and fatty acid composition) in seeds and fruit pulp, and SSR markers at 23 loci. The 78 accessions included 52 from ssp. mongolica, 6 from ssp. sinensis, and 20 hybrids. To assess the phenotypic diversity of these accessions, 8 agronomic fruit traits were recorded and analyzed using principal component analysis (PCA). The first two PCs accounted for approximately 78% of the variation among accessions. The oil contents were higher in pulp (3.46-38.56%) than in seeds (3.88-8.82%), especially in ssp. mongolica accessions. The polyunsaturated fatty acid (PUFA) ratio was slightly lower in the seed oil of hybrids (76.06%) than that of in ssp. mongolica (77.66%) and higher than that of in ssp. sinensis (72.22%). The monounsaturated fatty acid (MUFA) ratio in the pulp oil of ssp. sinensis (57.00%) was highest, and that in ssp. mongolica (51.00%) was equal to the ratio in the hybrids (51.20%). Using canonical correspondence analysis (CCA), we examined the correlation between agronomic traits and oil characteristics in pulp and seeds. Oil traits in pulp from different origins were correlated with morphological groupings (r = 0.8725, p = 0.0000). To assess the genotypic diversity, 23 SSR markers (including 17 loci previously reported) were used among the 78 accessions with 59 polymorphic amplified fragments obtained and an average PIC value of 0.2845. All accessions were classified into two groups based on the UPGMA method. The accessions of ssp. sinensis and ssp. mongolica were genetically distant. The hybrid accessions were close to ssp. mongolica accessions. The 8 agronomic traits, oil characteristics in seed and pulp oils, and 23 SSR markers successfully distinguished the 78 accessions. These results will be valuable for cultivar identification and genetic diversity analysis in cultivated sea buckthorn.

Identification and Analysis of Genetic Diversity Structure Within Pisum Genus Based on Microsatellite Markers

Little is known about the diversity of wheat in Qinghai Province, China. Agronomic traits and microsatellite markers were used to survey genetic diversity and its change with time in 66 wheat cultivars registered from 1957 to 2009 in Qinghai Province. The average values of plant height, ear length, spikelets per ear, effective spikelets per ear, effective tillers per plant, internode length under spike, kernels per spike, grain weight per ear, 1,000-grain weight, and distance of spike base to auricle of flag leaf were studied. The mean Shannon-Weaver diversity index (H’) was 1.67 and increased with time. One hundred and eighty nine microsatellite markers also were used to examine genetic diversity at a molecular level which showed that the average number of alleles (Na), genetic diversity index (He), and allelic richness (Rs) were 3.69, 0.5, and 3.45, respectively, and also increased with time but did not lead to a significant differentiation among the decades. These results suggest that the modern wheat breeding practice did not cause a genetic reduction in Qinghai Province.

Introduction Despite the fact that Iran is one of the major chickpea (Cicer arietinum L.) center of origins, limited information is available regarding chickpea genetic variation and diversity. Genetic diversity information is crucial for the choice of proper parents to establish new breeding programs. Chickpea germplasm is poor, suggesting the need for gaining enough knowledge of genetic diversity among available chickpea genotypes. A number of molecular techniques have been developed to unveil the genetic potentials of plant materials. Random Amplified Polymorpic DNA (RAPD) seems to be a reliable molecular marker to investigate the genetic diversity of chickpea genotypes in IRAN. The objectives of present research was: (1) to investigate the power of RAPD markers for estimation of genetic diversity among chickpea genotypes in west of Iran, (2) to investigate the genetic relationships between chickpea genotypes, and (3) to determine whether chickpea genotypes could be distinguished by RAPD marker data. Materials and Methods Random amplified polymorphic DNA markers (RAPD) were used to assess the genetic relationship between 18 different chickpea genotypes representing the cultivated chickpea cultivars in west of Iran. Genomic DNA was isolated according to Murray & Thompson (1980). Eighteen oligonucleotide primers were selected according to the number of literature published with the highest number of polymorphic bands. Polymerase chain reaction (PCR) was carried out in a total volume of 25 μl including 2 units of Taq DNA polymerase, 30 ng of genomic DNA template, 10 pmol of primers, 0.2 mM of dNTPs, and 2.5 μl of 10 × reaction buffer. DNA amplifications were performed in a thermocycler. The thermal profile was as follow: One time denaturation at 94◦C (5 min), followed by 40 cycles of denaturation at 94◦C (3 min), annealing at each primer proper Tm (1 min) and extension at 72◦C (2 min) and one time final extension at 72◦C (5 min). PCR products were analyzed on 1.5 % agarose gels in TBE buffer running at 100 V for 2h. The gels were stained using ethidium bromide and visualized with UV light. The reproducibility of the DNA band patterns was evaluated duplicate gel electrophoresis analysis. Only clear and repeatedly amplified RAPD DNA bands were scored as (1) for present bands and (0) for absent ones. Results and Discussion Out of 18 random RAPD primers used in this study, 17 primers amplified genomic DNA across all the genotypes. In total, 201 polymorphic bands (96.63%) out of 208 reproducibly scoreable RAPD markers were generated (OPM-05 primer did not produce any band). On average, 12.2 bands per primer were observed in RAPD analysis. Cluster analysis using Dice coefficient of similarity and UPGMA (r=0.98) method based on polymorphic fragments, grouped all eighteen genotypes into 6 groups with 77% accuracy. Based on dendrogram obtained, Bivanij (Landrace genotype) showed the least similarity with the 6th cluster. Although there was no redundancy among the genotypes tested, the majority of genotypes were clustered together. ICARDA genotypes may have been improved from an Iranian landrace. Conclusions Genetic diversity among chickpea cultivars using RAPD markers have been studied by a number of researchers. Although in most cases a low level of polymorphism with RAPD markers have been reported, this study showed a considerable amount of polymorphism. Furthermore, our results showed that cultivated chickpea cultivars in west of Iran have many genes in common. We recommend further studies to be conducted by using more number of chickpea genotypes as well as more robust molecular markers. Results of this study can be used in germplasm management/conservation practices, developing core collections and as guidance to plant geneticist and breeders for planning future explorations, and crop improvement purposes. These findings may help to avoid genetic vulnerability and erosion, keeping chickpea genetic diversity and germplasm.

Thirty-four soybean lines were assessed for twelve traits. The genetic distances were estimates using multivariate techniques, to identify parents to be included in breeding programs for hybridization. Grouping by the Tocher method, from generalized Mahalanobis distances, divided the 34 lines into four groups. The most important agronomic traits, weight of seeds per plot, plant height, height of first pod and days to maturity were considered when recommending for crossing. The following crosses were recommended based on the genetic divergence and the key agronomic traits: lines 23, 10, 2, 27 and 25 (group I) with genotype 6 (group II) and genotype 16 (group III). Thus only ten crosses would be made, representing only 2% of the total crosses which could be made in the partial diallel among the 34 lines assessed, which would allow up to 561 combinations.

Sustainable use of Genetic Diversity in Forage and Turf Breeding

In present study, an attempt has been made to assess the genetic diversity among 50 genotypes of Indian mustard using agronomic traits and random amplified polymorphic DNA (RAPD) markers. Variability was observed for agronomic traits viz plant height (cm), main shoot length (cm), days to flower initiation, number of siliquae on main raceme, number of seeds per siliqua, seed yield per plot (g), biological yield per plot (g), harvest index (%), days to maturity and 1,000-seed weight (g). Cluster analysis based on agronomic traits revealed a high degree of diversity among the accessions. Maximum variability was recorded for biological yield followed by seed yield, while minimum variability was observed for days to maturity followed by days to flower initiation. RAPD marker OPB8 was found to be the most informative primer followed by OPB14, OPB11 and OPB2. Both agronomic traits and molecular markers were effective in discriminating genotypes into different clusters, however, clustering pattern varied for both agronomic traits and molecular markers. Different clustering pattern based on agronomic data and RAPD markers indicated lack of association between genetic and phenotypic diversity implying that polymorphism due to RAPD is not linked to phenotypic variation. There was no relationship between place of origin and clustering of genotypes, however, diverse genotypes could be identified on the basis of both and are likely to produce more variability in segregating generations as well as to serve as parents for high heterosis.

Genetic variability analysis of 26 sheep breeds in the Czech Republic

The objective of this study was to compare methods of multivariate analysis on the evaluation of genetic diversity of mini tomato and to identify promising genotypes with resistance to pests. The experiment was conducted at the Vegetable Experiment Station of the Universidade Federal de Uberlândia, Monte Carmelo campus, from April 2013 to November 2016. The experimental design was a randomized complete block design with 16 treatments and four replications totaling 64 plots, and each plot represented by five plants. Sixteen genotypes were characterized, 12 from the F2RC1 generation, obtained through the interspecific crossing between the wild access LA-716 (Solanum pennellii) and pre-commercial lines of mini tomato (UFU-73 and UFU-2) (Solanum lycopersicum) and the UFU-2 lines. The content of acyl sugar, the amount of glandular trichomes (types I, IV, VI and VII), twospotted spider mite and whitefly resistance were evaluated. We concluded that there exist genetic variability between the genotypes. The number of groups formed by the canonical variated analysis was higher (four groups) than that obtained by the Tocher method (three groups) and UPGMA (three groups), demonstrating a greater discrimination power. The Tocher and UPGMA methods were consistent in the analysis of the genetic divergence in pest resistant germplasm of tomato, with the acyl sugar content being the most important variable. Genotype UFU-73-F2RC1 # 11 is resistant to pest attack, while the other studied lines have intermediate resistance.

Evaluation of genetic biodiversity for micronutrients is crucial for breeding high-quality crops and addressing the negative impacts of mineral deficiencies. The objectives of this research were to assess genetic variation and the relationship between grain Fe and Zn levels and agronomic traits in a diverse collection of wheat varieties. Additionally, the study aimed to determine the correlation between microsatellite markers (SSR) and micronutrient quantities. A total of 42 genotypes (Iranian commercial cultivars, landraces, and Afghan and Swiss varieties) were evaluated over a two-year period. Fe and Zn levels were measured using two semi quantitative staining assays and atomic absorption spectrophotometry (AAS) facility. Semi-quantitative staining methods and AAS showed high correlations for micronutrient contents. Landraces exhibited higher Fe (63.79 mg/kg) and Zn (44.76 mg/kg) but lower grain yield compared with commercial cultivars. Heritability estimates ranged 53%-79.43%, suggesting that genetic variance played a higher contribution in the phenotypic variation of traits than environmental factors. Notably, Fe content displayed significant correlations with days to maturity. Canonical correlation analysis (CCA) revealed that Zn content was correlated with four agronomic traits. Evaluation of genetic diversity using SSR markers demonstrated high genetic variation among the genotypes tested. The analysis of polymorphism information content (PIC) indicated that SSR primers had an average PIC of 0.75, with the Xgwm192 primer exhibiting higher PIC than others. Several SSR markers revealed association with micronutrient content that can be used in marker-assisted selection (MAS) programs aimed at selection of high micronutrient genotypes. In conclusion, the findings underscored the substantial genetic diversity present in micronutrient levels among global wheat genotypes, the potential of landraces for micronutrients biofortification of wheat cultivars through cross hybridization, the utility of staining methods for screening high/low micronutrient genotypes, and use of microsatellite markers for marker-assisted breeding aiming to micronutrient improvement in breeding programs.