Euphytica最新文献

Bitter vetch (Vicia ervilia (L.) Willd.), one of the Near Eastern founder crops, is an annual cleistogamous legume domesticated during the Neolithic period. Originally used for human consumption, over time it was replaced by other pulses and downgraded to a fodder crop. When coupled with a small degree of cross hybridization, cleistogamy confers evolutive plasticity to the plant species. The aim of the present work consisted in setting up optimal conditions to overcome the existing cross hybridization barriers in V. ervilia. Genotypes of Turkish origin, characterized by an erect growth habit were crossed with Italian counterparts characterized by high seed production. A detailed cyto-histological analysis of flower development was undertaken to determine the optimal stage for emasculation and manual cross. Ninety-eight crosses were carried out and the hybrid nature of the putative F1 progenies was assessed by SSR (simple sequence repeat) DNA markers. Fifty-five seeds were obtained of which only five gave rise to hybrid plants. Among these, only three turned out to be fertile and two of which generated a consistent number of F2 seeds whose plants were assessed in greenhouse for seed production and plant growth habit. Most of the evaluated traits showed mean values of the F2 plants intermediate between the two initial parents, confirming that intraspecific hybridization is not only possible but also useful to exploit the diversity confined in different bitter vetch populations.

Soil salinity is a major abiotic stress in agricultural production, as it hampers the growth and development of crop plants. Developing crop cultivars with salinity/salt tolerance is a major goal in many plant breeding programs. This study aimed to identify quantitative trait locus (QTL) that controls salt tolerance in the wild zombi pea (Vigna vexillata) accession “AusTRCF 322105.” For QTL analysis, a BC₁F₂ population resulting from the cross between salt-susceptible TVNu240 and TVNu240 × AusTRCF 322105 was used. A genetic linkage map was constructed for the BC₁F₂ population, consisting of 15 linkage groups and using 296 SNP markers. The map spanned 2889.9 cM in total length. Plant leaf wilt and plant survival were evaluated by subjecting the BC₁F₂ population to a hydroponic condition with 250 mM NaCl to assess salt tolerance at the seedling stage. QTL analysis revealed that two QTLs, qSaltol_3.1 and qSaltol_7.1, control both leaf wilt and plant survival. These two QTLs explained 23–27% and 11–15% of the trait variation. Exploration of the physical genome region revealed that qSaltol_3.1 is located near genes encoding methionine sulfoxide reductase and protein L-isoaspartate O-methyltransferase that are involved in oxidative stress resistance. In contrast, qSaltol_7.1 is located near genes encoding 3-ketoacyl-CoA synthase, L-type lectin domain containing receptor kinase VII.1, lipoxygenase 3, CBS domain-containing protein 5, NAC25 protein, and asparagine synthetase (ASNS) that have been found to be associated with salt tolerance. Nonetheless, qSaltol_3.1 and qSaltol_7.1 are novel QTLs identified for salt tolerance in the zombi pea.

Rice (Oryza sativa L.) is a common staple food widely cultivated and consumed globally. The increase in world population and slow genetic gain in rice production in the face of a rapidly evolving climate could cause food scarcity and decreased crop productivity. It is crucial to expedite the development and release of climate-resilient crop varieties through selective breeding and improvement to mitigate the impact of climate change. Speed breeding has emerged as a promising tool for rice breeding, offering the potential to accelerate the generation time. By streamlining the breeding process and reducing the time taken for each generation, speed breeding empowers breeders to screen for desired traits rapidly and efficiently, enhancing the selection and development of improved rice varieties to meet the growing global demand for food. This review focuses on the applications of speed breeding technology to accelerate rice breeding and further highlights the critical factors for speed breeding development in rice production, such as temperature, humidity, light, and genetic diversity. Understanding and optimizing these factors is vital in successfully implementing speed breeding technology in developing robust, high-yielding, and climate-resilient rice varieties for feeding the future.

Geraniums (Pelargonium spp.) are ornamental plants that are widely popular because of their abundant flowering, color variability, different flower patterns, and ease of cultivation. Genetic breeding of this species aims to reduce the plant size and flower color. The objective of this study was to carry out morphoagronomic characterization of parents and F₁ hybrids and to estimate the combined capacity and hybrid performance in the circulating diallel in F₂ geranium (Pelargonium sp.). We obtained 18 and 275 plants from the F₁ and F₂ generations, respectively. Characterization of the parental genotypes and F₁ and F₂ hybrids was performed based on the descriptors for Pelargonium. Parents and F₁ hybrids were grouped using the Tocher and UPGMA methods and diallel analyses in the F₂ generation. The F₁ hybrids G8, G11, and G17 exhibited color combinations suitable for commercialization and are promising for inclusion in breeding programs. The effects of general combining ability (GCA) and specific combining ability (SCA) were significant for these traits were also significant. The results showed the presence of both additive and non-additive genes. However, non-additive and dominant genes were predominant in most characteristics studied. Diallel analysis of the F₂ hybrids revealed that the best hybrid combinations for reducing plant height were 14 × 11, 14 × 13, and 15 × 12. Therefore, the implementation and use of diallel analysis were efficient in selecting superior parental genotypes and producing hybrids with high yields.

Yellow rust caused by Puccinia striiformis f. sp. tritici (Pst) is one of the most important wheat diseases. Adult plant resistance (APR) genes have gained the attention of breeders and scientists because they show higher durability compared to major race-specific genes. Here, we determined the effect of the APR genes Yr18, Yr29 and Yr46 in North-West European field conditions against three currently important Pst races. We used three pairs of sibling wheat lines developed at CIMMYT, which consisted of a line with the functional resistance gene and a sibling with its non-functional allele. All APR genes showed significant effects against the Pst races Warrior and Warrior (–), and a race of the highly aggressive strain PstS2. The effects of Yr18 and Yr46 were especially substantial in slowing down disease progress. This effect was apparent in both Denmark, where susceptible controls reached 100 percent disease severity, and in United Kingdom where disease pressure was lower. We further validated field results by quantifying fungal biomass in leaf samples and by micro-phenotyping of samples collected during early disease development. Microscopic image analyses using deep learning allowed us to quantify separately the APR effects on leaf colonization and pustule formation. Our results show that the three APR genes can be used in breeding yellow rust resistant varieties of spring wheat to be grown in North-West European conditions, and that deep learning image analysis can be an effective method to quantify effects of APR on colonisation and pustule formation.

An attempt was undertaken to comprehend how phenotypic markers, leaf tip necrosis (LTN), and pseudo black chaff (PBC), are associated with pleiotropic resistance genes in wheat (Triticum spp.). Pleiotropic resistance to stripe rust (Puccinia striiformis f. sp. tritici), leaf rust (P. triticina), stem rust (P. graminis f. sp. tritici) and powdery mildew (Blumeria graminis f. sp. tritici) was evaluated in 57 Egyptian spring wheat cultivars at seedling stage in greenhouse and at adult plant stage in field during 2021/22 and 2022/23. At seedling stage, pleiotropic resistance rated moderately resistance (MR) was observed in five cultivars, Misr-3 (all three rusts), Misr-4 (stripe rust, leaf rust, powdery mildew), Giza-168 (leaf rust, stem rust, powdery mildew), Sakha-94 and Sids-13 (leaf rust, stem rust). At adult plant stage, Misr-4 outperformed all other evaluated cultivars, exhibiting a high level of pleiotropic adult plant resistance (PAPR) against all diseases investigated. High levels of PAPR were also noticed against the three rusts in nine cultivars, Misr-3, Sakha-93, Sakha-94, Sakha-95, Giza-156, Giza-168, Giza-171, Gemmeiza-10 and Sids-13, and moderate levels against powdery mildew in Misr-3, Sakha-95, Giza-156. Four PAPR genes were characterized in cultivars based on phenotypic and molecular markers. Phenotypic markers (LTN and PBC) were observed in 23 cultivars. Molecular marker csLV34 indicated the presence of Lr34/Yr18/Sr57/Pm38/Ltn1 in six cultivars, whilst marker Xwmc44 indicated that Lr46/Yr29/Sr58/Pm39/Ltn2 was present in five cultivars. Marker Xcfd71 indicated the presence of Lr67/Yr46/Sr55/Pm46/Ltn3 in 19 cultivars. Gene Sr2/Yr30/Lr27/Pbc was identified with marker csSr2 in three cultivars. A complete association between LTN and molecular markers was recorded, while a strong association (r = 0.73) was recorded between PBC and molecular markers. Findings demonstrated the reliability of phenotypic markers in predicting pleiotropic resistance in wheat, which would facilitate marker-assisted selection in breeding programs.

Eucalyptus pilularis Smith is renowned for its high-quality wood, rapid growth, and adaptability to diverse soil conditions. This study aimed to evaluate the use of the molecular kinship matrix to estimate genetic parameters for E. pilularis selection and the potential establishment of a base population. The experiment involved 13 provenances and 115 progenies, using a randomized complete block design with five replicates and linear plots consisting of five plants each. Genetic parameters for the traits diameter at breast height (DBH), total height, and volume were evaluated at five years of age using the linear mixed model. Results indicated a survival rate for the population of 73.11%, an average total height of 18.65 m, DBH of 14.28 cm, and volume of 14.57 cm³. By adjusting the kinship matrix, the estimated values of heritability and genetic coefficients of variation decreased, indicating that there would be errors in these estimates and in the genetic gains if the progenies were assumed to be half-siblings. The discrepancy in rankings derived from the conventional half-sibling matrix versus molecular kinship matrix poses a significant challenge for experts in forest species genetic improvement. Our findings indicate not only inflated estimations of genetic parameters and gains, but also disparities in rankings when accounting for true levels of relatedness among individuals based on the molecular matrix.

Almonds are one of the most popular and widely consumed tree nuts in the world, prized for their taste, texture, and nutritional benefits. However, the quality and characteristics of almonds can vary significantly depending on the variety and growing conditions. In this context, a comparative study was conducted to explore the nut quality traits of almond local and foreign cultivars, as well as their F1 hybrid offspring resulting from crossbreeding. “Nut quality” is a dynamic concept changing based on consumer needs and perceptions that reflect sociocultural evolution. The aim of this study was to identify the most promising almond varieties and hybrids based on some nut quality traits including macro–micro elements and tocopherol contents. To accomplish this goal, samples were collected from local (Gulcan 2 and Nurlu) and foreign (Lauranne and Guara) almond cultivars, as well as F1 hybrid offspring resulting in two cross-breading (“Gulcan 2 × Lauranne” and “Guara × Nurlu”), and conducted a comprehensive analysis using high-performance liquid chromatography and atomic absorption spectroscopy. Our results showed that the nut quality traits of almonds can vary significantly among different cultivars and hybrids, with some varieties and hybrids exhibiting superior characteristics compared to others. These findings provide important insights into the potential for improving almond quality through crossbreeding and the development of new varieties with improved characteristics which can help inform breeding programs and improve the quality of almonds available in the market.

Doubled haploid (DH) production technology has been a valuable tool for the development of homozygous lines through anther culture within a short period in comparison with conventional breeding methods. Doubled haploid production in pearl millet through anther culture helps to overcome inbreeding depression which occurs due to continuous selfing for homozygous line development. We developed an efficient method to develop DH plants through anther culture in pearl millet in large numbers, which is the first report in pearl millet. The method encompasses a selection of the right stage of mother plant, optimal culture media, and influence of temperature for treatment of anther for callus induction followed by plant regeneration and flow cytometric analysis for ploidy determination. Anther culture experiments were done in proprietary pearl millet genotype of Rasi seeds ‘1988F₁’ (R × R cross) for achieving better calli or embryo induction and green plant regeneration in pearl millet. A significant frequency of 35.4% calli-embryoid response in Doubled-haploid Pearl millet Media (DPM4) was achieved at incubation temperature of 32 °C for spikes pre-treatment and anther initiation. This response was further improved to 44.4% by separating anthers from spikes on fourth day of incubation. Alteration of basal salt concentration and inclusion of 12% maltose as carbon source in calli induction media resulted in a higher number of embryo-like structures (ELS) which eventually increased the regeneration up to 12.9% in Regeneration Media (RM3). These experiments resulted in a promising procedure to develop DH plants in pearl millet to minimize the timeline for pure line development and trait introgression to accelerate breeding program.

The site regression model (SREG) is utilized by plant breeders for analyzing multi-environment trials (MET) to examine the relationships among test environments, genotypes (G), and genotype-by-environment interactions (GE). SREG explores a matrix of G and GE by performing a singular value decomposition on the residuals matrix from a one-way ANOVA, requiring complete data. As missing values are common in MET, we propose two new imputation methods that implement an Expectation Maximization algorithm to fit the SREG model. To evaluate the impact on SREG model parameter estimation of these proposed methods and other competing imputation methods available, we conducted two studies using different approaches. One study involved simulated data while the other used a real dataset. In both studies, different measures to verify whether the joint effect of G plus GE is altered by imputation of data, and the reproducibility of missing data were evaluated. We also incorporated situations not commonly addressed in the literature, such as non-random structures of missing values and a big data situation. The proposed procedures provided estimators with good performance, maintaining superiority in several aspects studied, even when the competing imputation methods did not achieve convergence. Therefore, the new methods enabled incomplete MET data to be effectively analyzed by a SREG model.