During recent decades, global warming has intensified, altering crop growth, development and survival. To overcome changes in their environment, plants undergo transcriptional reprogramming to activate stress response strategies/pathways. To evaluate the genetic bases of the response to heat stress, Conserved DNA-derived Polymorphism (CDDP) markers were applied across tomato genome of eight cultivars. Despite scattered genotypes, cluster analysis allowed two neighbouring panels to be discriminate. Tomato CDDP-genotypic and visual phenotypic assortment permitted the selection of two contrasting heat-tolerant and heat-sensitive cultivars. Further analysis explored differential expression in transcript levels of genes, encoding heat shock transcription factors (HSFs, HsfA1, HsfA2, HsfB1), members of the heat shock protein (HSP) family (HSP101, HSP17, HSP90) and ascorbate peroxidase (APX) enzymes (APX1, APX2). Based on discriminating CDDP-markers, a protein functional network was built allowing prediction of candidate genes and their regulating miRNA. Expression patterns analysis revealed that miR156d and miR397 were heat-responsive showing a typical inverse relation with the abundance of their target gene transcripts. Heat stress is inducing a set of candidate genes, whose expression seems to be modulated through a complex regulatory network. Integrating genetic resource data is required for identifying valuable tomato genotypes that can be considered in marker-assisted breeding programmes to improve tomato heat tolerance.

Low molecular weight glutenin subunits (LWM-GSs) play a crucial role in determining wheat flour processing quality. In this work, 35 novel LMW-GS genes (32 active and three pseudogenes) from three Aegilops umbellulata (2n = 2x = 14, UU) accessions were amplified by allelic-specific PCR. We found that all LMW-GS genes had the same primary structure shared by other known LMW-GSs. Thirty-two active genes encode 31 typical LMW-m-type subunits. The MZ424050 possessed nine cysteine residues with an extra cysteine residue located in the last amino acid residue of the conserved C-terminal III, which could benefit the formation of larger glutenin polymers, and therefore may have positive effects on dough properties. We have found extensive variations which were mainly resulted from single-nucleotide polymorphisms (SNPs) and insertions and deletions (InDels) among the LMW-GS genes in Ae. umbellulata. Our results demonstrated that Ae. umbellulata is an important source of LMW-GS variants and the potential value of the novel LMW-GS alleles for wheat quality improvement.

Core subset selection from collections hosted by seed banks, grow in importance as the number of accessions and genetic marker information rapidly increases. A data set of 20,526 single-nucleotide polymorphism (SNP) markers characterizing 7986 Mexican creole wheat landraces, was used to test 11 methods for core subset selection, through optimization criteria containing average genetic distance and genetic diversity. Allele richness was used as an additional criterion to qualify the generated core subsets. Three replications with random samples of 1500 SNP loci, each comprising a maximum of 3000 alleles, were used to perform the method evaluations through four different objective functions. The LR greedy search (LR) and LR with random first pair (LRSemi) were consistently best across all assays for maximizing the objective functions, and they performed well even for criteria not included in those functions. The Tukey's HSD (honest significant difference) multiple comparisons grouped those methods together with the sequential forward selection (SFS) and SFS with random first pair (SFSSemi) strategies as the top set of approaches. All of them are simple heuristic maximization algorithms, and outperformed two more sophisticated optimization approaches: parallel mixed replica exchange and replica exchange Monte Carlo. For their efficiency to optimize the objective functions and computing speed, the LRSemi and SFSSemi methods demonstrated to be good alternatives for core subset selection from large collections of highly homozygous accessions characterized by many biallelic markers.

Full potential of African tomato has not been tapped due to lack of information regarding its characterization. The aim of this work was to study the diversity of 17 African tomato landraces collected from Solanaceae gene bank – Tanzania. Evaluation was done using Complete Random Block Design. Morphological data collected were subjected to GenStat's and Darwin6 software. RNA was extracted from leaf samples, fruits at three ripening stages using modified Trizol method and sequencing done using Illumina sequencing platform. The raw reads were filtered and analysed using the Bioinformatics tools. Phenotypically, the landraces clustered into three clusters dendrogram representation. Clustering was attributed by phenotypic variation. Analysis of variance showed significant phenotypic variations among the landraces (P < 0.05). A total of 115,965 validated single nucleotide polymorphisms (SNPs) were mined from the 303,754,051 high-quality filtered reads. Molecular characterization showed significant variation within the landraces at fruit development stages. Unlike the phenotypic variation, phylogenetic tree representation grouped the 17 landraces according to their geographical location with some landraces from different countries grouping together. The findings of this study reveal significant morphological variation among African tomato contributed by plant height, leaf blade length, leaf blade width and fruit width. Positive correlation between fruit width and yield (r = 0.93, P < 0.01) was observed. Results of this study reveal that there is admixture of landraces from various geographical locations. Morphological characterization of African tomato can only lay a foundation but it does not reveal genetic diversity. The transcriptome SNP analysis revealed significant variation among the African tomato according to their geographical location.

We have compared the genetic diversity of 24 Chinese weak-winter, Swedish winter and spring Brassica napus accessions by inter-simple sequence repeats (ISSRs). Using cluster analysis (UPGMA) based on 125 polymorphism bands amplified with 20 primers, the 24 accessions were divided into three groups. Six Swedish winter lines and eight Chinese weak-winter lines were in group I and group II consisted of two Chinese weak-winter lines, Xiangyou15 and Bao81. The third group contained eight Swedish spring lines. Principal coordinates (PCO) analysis showed similar groupings to cluster analysis. Results from cluster analysis and PCO analysis showed very clearly that Chinese weak-winter, Swedish spring and winter accessions were distinguished from each other and Chinese weak-winter accessions in this study were genetically closer to Swedish winter accessions than to Swedish spring accessions. The Chinese weak-winter accessions had larger diversity than the Swedish spring or winter accessions. This study indicated that ISSR is a suitable and effective tool to evaluate genetic diversity among rapeseed germplasm.

Plant height in chickpea is a multivariate, dynamic trait, and shows differences in growth rate at different stages of plant development in different genotypes. In the majority of plant-breeding experiments, the phenotypic data on a quantitative trait measured at a fixed time point (generally at maturity) are used for quantitative trait loci (QTL) mapping. However, this method can result in missing important/major QTLs which are expressed at different time points and are not expressed at maturity. In the current study, using a set of 49 desi chickpea genotypes sown at three different durations for two successive years, we observed that heritability for plant height was highest at the 2 month stage in the normal sown trial, and at the 1 month stage in late-sown trials. However, heritability drastically declines at maturity, particularly due to heat stress with an increase in temperatures during the growing period. In the association analysis, it was also observed that almost all the marker–trait associations (MTAs) identified using endpoint phenotypes were identified using data obtained at different intervals. In addition, some novel and stage-specific MTAs were identified using phenotypic data recorded at monthly intervals. The results highlight the importance of multistage phenotyping for dynamic traits like plant height in germplasm characterization programmes.

Since the 1600s, a pasta wheat locally known as Sargolla, Saragollio or Saragollo has been cultivated in central and southern regions of Italy, including Abruzzo and Puglia. To identify if distinctive Saragolla landraces are present in Abruzzo and with a view to registering them as Conservation Varieties in the Abruzzo Regional Register of Genetic Resources, a quantitative botanical characterization of 11 farm-saved seed samples from Abruzzo and a previously defined Saragolla landrace from Puglia was performed. All twelve samples were grown for two years at the CREA-CI field station in Foggia, Puglia (Italy), and were morphologically characterized according to the criteria used by the botanist Johan Percival in 1921. In the 12 samples, we identified 9 taxonomically different botanical types, the most frequent of which were the italicum (32%), found in every population from Abruzzo. The leucurum and the affine were the main components of the previously defined Saragolla from Puglia. Results of the multivariate analysis indicated that the samples collected from farms in Abruzzo are more similar to each other than to the landrace of Saragolla from Puglia and support the registration of a specific Saragolla landrace for the Abruzzo region. The diachronic comparison of the botanical diversity of the currently cultivated Saragolla, with that observed in Sicily and Algeria at the beginning of 1900, suggests that a high degree of genetic diversity still exists in the 11 Saragolla populations from the Abruzzo Region.

Existence of genetic divergence, appropriate characterization of breeding lines for economically important traits and determining parents with favourable alleles is the crux of crop genetic improvement programmes. This study is the first report of unravelling genetics and potential of petaloid-type cytoplasmic male sterile (pt-CMS) lines in carrot. Ten pt-CMS lines were crossed with 10 inbreds in line × tester mating fashion to generate 100 testcross progenies. Nutritional profiling of the 100 testcrosses progenies along with 20 parental types was carried out for two consecutive years for eight important traits to identify superior combiners. The pooled analysis revealed that the carotenoid content in root is under the genetic control of major genes (oligogenic). The pooled analysis revealed less than unity value of σ2A/D and σgca2/σsca2 for majority of the traits depicting preponderance of non-additive gene effects. The pt-CMS lines KT-28A, Kt-62A, KT-80A and KT-95A were identified as good combiners for carotenoids. The cross combination, KT-98A × KS-50 identified as the best heterotic combiner for CUPRAC and FRAP content over the years. Similarly, the combinations, KT-62A × KS-21, KT-80A × New Kuroda and KT-62A × KS-59 were found promising across the years for developing nutritionally rich F1 hybrids. The interaction analysis among the different antioxidant traits and plant pigments unveiled the scope of simultaneous improvement.

Big bud caused by several different phytoplasmas is an emerging threat to tomato production worldwide. The development of resistant varieties would be an effective approach to manage this problem, but it requires an appropriate screening technique. Recently, we have described a simple and efficient chip graft inoculation assay (CGIA) for the first time to screen tomato germplasm against Tomato leaf curl New Delhi virus. The present study was conducted to first validate the CGIA for phytoplasma transmission, then to assess the resistance of 74 genotypes belonging to different Solanum species against 16SrII-D phytoplasma. CGIA success rate and phytoplasma transmission was 100% since all the grafts survived and phytoplasma was detected in these plants using nested polymerase chain reaction. No genotype was found resistant as all the grafted plants showed typical disease symptoms. In addition to phytoplasma transmission, CGIA can be used for better understanding the plant–phytoplasma interactions and biology of phytoplasmas in tomato.

The plant Camellia fascicularis, belonging to family Theaceae, has high ornamental and medicinal value, and rare gene resources for genetic improvement of Camellia crops, but is currently threatened with extinction because of the unique and extremely small wild populations. Molecular markers have clarified the wild plant species’ genetic diversity structure, new gene resources and relationship with crops. This will be beneficial for conservation of these valuable crop-related wild species and crop improvement. In this study, we identified 95,979 microsatellite loci from 155,011 transcriptome unigenes, and developed 14 polymorphic expressed sequence tag-derived simple sequence repeat (EST-SSR) microsatellite markers for C. fascicularis. The number of alleles (Na) per locus was 2–8 with a mean of 4.86. The genetic diversity of 40 individuals from four natural populations of C. fascicularis was analysed using these polymorphic markers. The number of alleles (Na) for EST-SSR ranged from 2 to 5, with the expected heterozygosities (He) and observed heterozygosities (Ho) in all loci ranging from 0.183 to 0.683, and from 0.201 to 0.700, respectively, implying a rich genetic variation present in wild C. fascicularis populations. Moreover, the phylogenetic analysis among four populations, using the 14 EST-SSR markers developed in this study, grouped 40 individuals into three groups, which coincide with their geographic distribution. These results showed that 14 EST-SSR markers are available for the analysis of genetic variation in C. fascicularis populations and genetic improvement of new Camellias cultivars by interspecific hybridization, and are beneficial for conservation of the endangered species.

Bambara groundnut (Vigna subterranea (L.) Verdc) has been neglected in terms of variety selection and development which has resulted in farmers growing a mixture of landraces that are not genetically characterized and are low yielding. With the need to set up a breeding programme in Malawi, it was necessary to thoroughly understand the genetic diversity (GD) present in the available germplasm. The objectives of the study were to assess Bambara genotypes GD using agro-morphological traits and SNP markers, and to identify and select high yielding Bambara genotypes. Field trials were conducted for two seasons at Bunda College. Later, genotypes were genotyped using DartSeqLD SNP markers. All data were analysed using R Package. Significant genetic variations (P < 0.001) were observed for most traits including grain yield, which suggests that genetic variability exists in Bambara groundnuts which can be exploited in breeding programmes aimed at developing high performing varieties. Based on grain yield, the study identified 18 top performing genotypes across the evaluation seasons which will be tested under farmers’ fields’ conditions. DArTseqLD grouped the genotypes into three clusters. It was noted that majority of the genotypes from the same origin clustered together. High genetic distances were observed between genotypes from Southern African and West African regions and this has important implications in parental selection for the genetic improvement of Bambara. Our results provide valuable insights about the extent of genetic variability and how parental lines can be selected for improved genetic gain in Bambara groundnuts.

A better understanding of diversity in landraces is essential for planning crosses for the development of trait specific varieties with better adaptability and stability. In the present study, 120 wheat genotypes comprised of landraces, genetic stocks, released varieties and improved genotypes were evaluated in randomized block design for 14 agro-morphological traits. The clustering method and principal component analysis (PCA) programme of Statistical Package for Agricultural Research (SPAR1) was used for grouping the genotypes. These 120 genotypes were grouped into nine clusters based on agro-morphological traits. These nine clusters differed significantly on the basis of mean values for 14 agro-morphological traits. PCA showed that the two principal components (PC1 to PC2) exhibited about 49% of the total variability. Scatter plot was constructed by plotting scores of PC1 and PC2. Based on mean values obtained over two years, the diverse superior genotypes were identified for utilization in hybridization programme. From the present study, we conclude that cluster analysis grouped the landraces with greater agro-morphological similarity into one group rather than geographical isolation indicating that geographical origin may not be the only factor causing diversity. Further, released varieties exhibited superiority for grain yield, while many landraces had higher values for number of tillers in a meter, biomass and thousand-grain weight (TGW). Thus, for the improvement in TGW in released varieties, the hybridization between superior landraces for TGW from cluster ‘E’ and released wheat varieties from cluster ‘C’ could give desirable segregates.

Sheath rot is one of the most destructive emerging diseases of rice in Asia and a significant loss (20–85%) to rice production is caused by this disease under temperate agro-climatic conditions of Kashmir. Disease is more prevalent in higher belts of valley where Japonica rice cultivation is more common. Also, late-maturing varieties are more likely to be attacked by sheath rot disease of rice. Information regarding the occurrence and distribution of any pathogen and its variability in the field is very much essential to devise a suitable disease management programme against the particular pathogen. The isolates of Sarocladium oryzae tested in the present study exhibited considerable variation in cultural characteristics, morphology and pathogenicity. The resistant sources for sheath rot disease of rice were identified among the temperate germplasm of rice under a relatively high inoculum concentration and disease pressure of all the variable isolates of S. oryzae. Among 219 rice genotypes screened for resistance against S. oryzae under field conditions, 42 genotypes were further evaluated under controlled epiphytotic conditions against all the 18 isolates of S. oryzae. Four genotypes (SKUA-354, ORN-V4, GS-183, GS357) were finally selected with high resistance against sheath rot disease of rice which can be utilized as potential donors for the development of disease-resistant varieties of rice against sheath rot.

In Ethiopia, the low productivity of garlic is largely due to a shortage of high yielding and stable varieties. To address this issue, thirteen garlic genotypes were evaluated for yield stability and performance across six different environments in central and southeast Ethiopia. The genotypes were analysed using Additive Main effects and Multiplicative Interaction (AMMI) and genotype-by-environment interaction (G × E) methods. Results showed that the genotypes differed significantly for bulb yield performance and morphological traits, with G-020/03 and G-054/03 producing the highest bulb yield with 25.39% and 18.39% yield advantages over the check variety, Kuriftu, respectively. Furthermore, G-020/03 demonstrated better yield stability across most environments, while G-054/03 exhibited specific adaptability. GGE biplot analysis confirmed that these two genotypes were among the three winning genotypes in terms of yield performance and relative stability. Therefore, G-020/03 and G-054/03 have been selected as candidate varieties for release, potentially improving garlic productivity in Ethiopia.

The article presents the results of the search for microsatellite or simple sequence repeat (SSR) loci with tri-, tetra-, penta- and hexanucleotide tandem repeat motifs in the draft de novo assembly of the Siberian fir (Abies sibirica Ledeb.) genome and the development of convenient relatively highly and moderately polymorphic markers that can be easily genotyped even by simple gel electrophoresis. In total, 64 pairs of oligonucleotide polymerase chain reaction (PCR) primers for 32 detected microsatellite loci were designed and tested. Based on the testing results, 10 most promising polymorphic loci were selected and genotyped in eight natural populations of Siberian fir. Homologous microsatellite loci in the genome of European silver fir (Abies alba Mill.) were also identified by mapping Siberian fir contigs, containing SSR loci to the European silver fir genome assembly. A multiplex panel of 14 universal microsatellite loci was developed and genotyped in samples from four natural populations of A. alba and a small sample of eight Nordmann fir (Abies nordmanniana (Steven) Spach) trees.

In the face of climate change, developing resilient crops is crucial for global food security in the 21st century to feed a growing population. Lentil (Lens culinaris Medikus) plays a vital role in ensuring global food and nutritional security. Traits like early flowering enable the crop to mature faster, thereby shortening the growing window and reducing yield losses caused by moisture and heat stresses during the reproductive phase. However, issues like limited genetic diversity in this trait remain unaddressed. To address this gap, our study aims to comprehensively assess genetic variability and trait associations in 158 lentil accessions. In the present study, we observed significant variations for days to 50% flowering (67–90 days), days to maturity (109–122 days) and 100 seed weight (1.69–2.68 g) throughout a period of two consecutive years (2020–2021 and 2021–2022). The observed variability in these traits offers a valuable avenue for the improvement of lentil yield through targeted selection and hybridization. Additionally, correlation analysis showed negative correlation between days to 50% flowering and grain yield per plant, while plant height had a significant (P < 0.01) positive correlation with all traits except yield per plant. Furthermore, we identified specific germplasm with exceptional traits that hold significant potential for future breeding programmes. The genotypes EC 223197-A and EC 267696 were identified for early flowering with high yield, and other genotypes that were identified for various traits would serve as breeding material for the introgression of these traits into elite cultivars.

Diversity in agronomically important traits of wild emmer wheat, Triticum dicoccoides, the progenitor of most cultivated wheats, was examined in l60 genotypes representing 16 populations derived from a wide ecogeographical spectrum of climate, soil and water availability in Israel and Turkey. The analysis included 14 quantitative economic characters including heading date, culm length, biomass, grain yield and its components, and grain protein percentage.

The results led to two major conclusions: (i) agronomically important traits varied genetically: ecogeographic diversity in these traits is dramatically displayed when populations are grown in a relatively standardized environment; and (ii) genetic diversity is revealed not only between, but also within populations. Thus, genotypes excelling in some of these characters were found in several populations.

Teosinte, the wild progenitor of maize, has immense potential for providing unique traits and is more divergent compared to inbred lines and landraces. One hundred and sixty-nine teosinte-introgressed maize backcross inbred lines were developed to widen the genetic base of maize with predomestication alleles. The population was evaluated phenotypically and genotypic data of 76 SSR markers were used to map quantitative trait loci (QTLs) governing the targeted traits. Sixty-six QTLs were detected for eight plant architect-related traits that are spread over 10 different chromosomes with phenotypic variation ranging from 2.29 to 13.97%. Maximum three stable QTLs were recorded for days to anthesis (DA) followed by two for days to silking (DS), plant height (PH) and node bearing first ear (NBE). For rest of three traits namely flag leaf length (FLL), flag leaf width (FLW) and ears per plant (E/P) only one stable QTL was detected. Among the 16 common QTLs, the marker phi328178-linked QTL governed four characters (DA, DS, FLL, FLW) simultaneously, followed by umc1622-linked (ASI, FLW, E/P), umc2341-linked (DA, DS, NBE) and phi075-linked QTLs (ASI, PH, NBE) controlling three traits each. Remaining 12 QTLs controlled two characters. Molecular association between co-localized QTLs for different traits was also validated at the phenotypic level by significant correlation estimates. For eight studied traits, 53 superior lines were identified which along with parents (teosinte and maize inbred DI-103) were grouped into 12 clusters. Therefore, lines clustered independently can be combined to accumulate desirable traits for the improvement of maize.

DNA fingerprinting using microsatellites is a useful aid in cultivar identification, but has rarely been applied to garden plants. Eleven microsatellite markers were developed for the valuable garden plant Hesperantha coccinea (Schizostylis coccinea), and used to determine relatedness of accessions. Several accessions, described as separate cultivars, appeared to have identical genotypes. Among the 53 accessions tested, there were 34 unique multilocus genotypes. The level of polymorphism detected in the cultivars was high, with on average seven alleles per locus and an average expected heterozygosity of 0.72 across loci. It is clear from the genotypes that a large proportion of the cultivars are closely related to each other. The resulting markers can now be used to generate a complete database of all known cultivars of the species and to detect essentially derived cultivars. As an extension of this study, the markers identified here could also inform us about the genetic diversity in wild populations.