Selection of desirable phenotypes and characterization of variability in economically important traits are essential for domestication of indigenous fruit trees (IFTs). Currently, participatory tree selection is a widely accepted approach in IFT domestication wherein farmers' knowledge and preferences are included in tree selection processes. In Arunachal Pradesh, India, fruits of Phoebe cooperiana are extensively consumed by people and traded across the state. In this study, we employed a selection index to screen trees for superior fruit traits from a base population of 45 farmer-identified trees of P. cooperiana in Arunachal Pradesh. Based on fruit diameter length ratio, pulp fruit ratio and yield, 19 trees were selected for superior fruit traits. The per cent improvement for 10 fruit and seed traits ranged from 0.16 to 14.56% compared to the base population. Significant variation for all fruit and seed parameters was observed among the 19 trees with coefficient of variation values ranging between 1.92% for fruit diameter and 8.26% for seed weight. There was significant positive association between economic traits including fruit weight with pulp weight, fruit diameter length ratio with fruit weight and pulp thickness with pulp weight. Principal component analysis revealed that variability was largely contributed by fruit weight (0.49), pulp weight (0.46), seed weight (0.45) and fruit diameter (0.42). Cluster analysis grouped phenotypes into seven groups with no clear clustering of individuals from the same area. The study highlights the significance of participatory tree selection approach and the benefits of individual tree selection in capturing wider variation and locating extreme phenotypes in IFT domestication.

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.

Jatropha (Jatropha curcas L.) is a shrub that produces non-food oil and can potentially be used for biodiesel production. An interspecific cross was made between J. curcas and peregrina (J. integerrima) to increase genetic diversity. Interestingly, male sterility was observed in the F2 population. Out of the 445 F2 plants, five, namely, ms-1 to ms-5, exhibited male sterility, characterized by unopened and distorted stamens without pollen. The parental jatropha, peregrina, F1 and F2 had fertile pollen grain rates of 90.61%, 96.39%, 81.46% and 75.39%, respectively. To verify the fertility of the pistils in the male sterile plants, they were pollinated through selfing, opening and hand crossing with fertile pollen. All of the ms lines experienced seed abortion with or without fruit, except for ‘ms-5’, which produced seed.

This study evaluated the morphological diversity of some Nigerian accessions of Bambara groundnut. Field experiments were conducted in Nigeria in two locations and the phenotypic variation of Bambara groundnut accessions evaluated in 3 years (2017–2020) using a randomized complete block design. Twenty-eight quantitative and 10 qualitative traits were observed. Twenty-three out of the 28 quantitative morphological traits showed significant differences. TVSu-589 (28.85) and TVSu-670 (28.57) had the highest plant height; TVSu-572 (121.52), TVSu-271 (113.10) and TVSu-336 (104.15) had the highest 100-seed weight. Genetic variations were also observed in seed colour, terminal leaflet shape, petiole colour and eye pattern. Principal component analysis showed PC1 constituting 23.36% and PC2 constituting 15.76% of the total variation, while the first eight principal components with eigenvalues ≥1 revealed 77.28% of the total variation. Cluster analysis grouped the accessions into four groups. Based on yield data in this study, accessions TVSu-594, TVSu-350, TVSu-336, TVSu-1242, TVSu-129, TVSu-14, TVSu-179, TVSu-2100, TVSu-261 and TVSu-589 were the best for yield and are recommended for further evaluation to improve yield. This study showed that a wide range of diversity exists in Bambara groundnut of Nigerian origin that could be useful for further utilization of genetic resources and improvement.

Soybean is a major source of vegetable oil and protein worldwide. Globally, India is among the top five producers where soybean is a major oilseed grown under diverse agro-climatic conditions by small and marginal farmers. The present study aims to identify soybean varieties with higher yield levels, resistance to pestdiseases and adaptability to climatic fluctuations. One hundred and twenty-five (125) indigenous and exotic soybean germplasm accessions and five checks were evaluated and characterized for eight agro-morphological traits at five testing locations and also screened for frog-eye leaf spot (FLS) and yellow mosaic virus (YMV) diseases under hot-spot locations during the rainy season. A wide range of variability was observed among accessions for days to 50% flowering (39–59), plant height (41–111 cm), number of nodes/plant (10–30), pod clusters/plant (14–39), number of pods/plant (40–102), days to maturity (96–115), grain yield/plant (4.89–16.54 g) and 100-seed weight (6.02–13.72 g). Among various traits, 100-seed weight (0.45), number of pods/plant (0.60) and number of pod clusters/plant (0.38) were found to be major yield-contributing traits as they exhibited highly significant correlation with grain yield/plant. Principal components PCI and PCII with eigen value >1 accounted for 42.66 and 27.08% of the total variation, respectively. Accessions G24 (EC 393222) from Taiwan and G40 (IMP-1) from the USA belonging to cluster IV were found promising for multiple yield traits and JS 20–38 from cluster III for earliness as per cluster analysis. GGE biplot average environment coordination (AEC) view revealed that the accessions viz., G11 (EC 333872), G2 (EC 251506) and G47 (TNAU-S-55) were the best performing stable genotypes in terms of grain yield/plant across locations. Twelve accessions had a high level of resistance against both FLS and YMV diseases under natural hot-spot conditions which can be utilized as promising donors in the soybean breeding programme.

Low level of resistance to major diseases such as ascochyta blight (AB), botrytis grey mould (BGM) and dry root rot (DRR) in the cultivated chickpea genepool necessitates harnessing wild Cicer species. Sixty-eight accessions belonging to eight annual wild Cicer species and seven chickpea cultivars were screened for AB, BGM and DRR under controlled environmental conditions over the years. Intra-accession variability was observed among wild Cicer accessions for each disease. Hence, progenies of single resistant plants were selected for further evaluations and the trait-specific genetic stocks (TGS) were developed for each disease after re-screening following the single seed descent method. For AB, a high level of resistance was identified in four accessions belonging to tertiary genepool species, ICC 17334 (Cicer judaicum), ICC 17302, ICC 17308 and ICC 20177 (C. bijugum). Nine accessions, ICC 17160, ICC 17264, ICC 17270, ICC 20170, ICC 20186, ICC 20225, ICC 20247, ICC 20251 and IG 72941 of primary (C. reticulatum) and one accession, ICC 20190 of secondary (C. echinospermum) genepool species were resistant to BGM whereas, four accessions, ICC 20187 (C. reticulatum) and ICC 20218, ICC 20244 and ICC 20257 (C. echinospermum) were resistant to DRR. Development and utilization of these TGS in chickpea pre-breeding will assist in developing disease-resistant chickpea cultivars with broad genetic base.

Common lilac (Syringa vulgaris L.) is a popular landscaping plant. Our aim was to obtain a large set of single nucleotide polymorphism (SNP) markers, to reveal the precise identities of the investigated S. vulgaris accessions, and to discover genetic relationships among them. The studied plant material included local Finnish, previously unidentified accessions, known reference cultivars, and so-called historical accessions i.e., old shrubs growing in historic cultural landscapes. We intended to verify cultivar names for some valuable local common lilac accessions and to provide insights into the history of common lilac cultivation in Finland. In the analyses, we used a set of 15,007 SNP markers. First, polymorphic information contents were calculated (mean 0.190, range 0.012–0.500 per marker). Then, to investigate genetic relationships among genotypes, a phylogenetic tree was constructed, and a principal coordinate analysis was conducted. A Bayesian analysis of population structure was performed to determine the number and distribution of genetic clusters among samples. Genetic marker data combined with existing historical and phenotypic knowledge revealed novel information on the unidentified cultivars and on the genetic relationships among studied accessions and solved the arrival and early history of common lilac in Finland. Overall, such comprehensive genomic characterization and deep understanding of genetic relationships of S. vulgaris can be used when utilizing present cultivars and developing new ones in future breeding programs.

A total of 32 sweet potato genotypes were evaluated to assess the genetic diversity based on quantitative traits and molecular markers, as well as stability for yield and related traits. Wider variability was observed for the traits like vine length (181.2–501.3 cm), number of leaves/plant (103.0–414.0 cm), internodal length (3.20–14.80 cm), petiole length (6.5–21.3 cm), leaf length (8.50–14.5 cm), leaf breadth (8.20–15.30 cm), leaf area (42.50–115.62 cm2), tuber length (7.77–18.07 cm), tuber diameter (2.67–6.90 cm), tuber weight (65.60–192.09 g), tuber yield (7.77–28.87 t ha−1), dry matter (27.34–36.41%), total sugar (4.50–5.70%) and starch (18.50–29.92%) content. Desirable traits such as tuber yield, dry matter and starch content have shown high heritability (>60%) with moderate to high genetic advance. Under molecular analysis, a total of 232 alleles were observed from all 32 microsatellite markers, which ranged from 4 to 14 with an average of 7.77 alleles per locus. In the population, the average observed heterozygosity (0.51) was higher than the expected heterozygosity (0.49). The contribution of genotype, genotype by environment interaction to the total variations was found to be significant. Based on the multi-trait stability index (tuber length, tuber diameter, tuber weight and tuber yield), genotypes X-24, MLSPC-3, MLSPC-5, ARSPC-1 and TSP-12-12 were found to be most stable. Among them, the high-yielding and stable genotypes TSP-12-10 (26.0 t ha−1) and MLSPC-3 (23.9 t ha−1) can be promoted for commercial production or used as parental material in future crop improvement programmes.

A breeding programme of aromatic vanilla, dating back to 1944, was conducted in Ambohitsara, Antalaha, SAVA (Sambava, Antalaha, Vohemara, Andapa) – Madagascar. Imported, local, wild and cultivated vanillas were used as progenitors and thousands of hybrids were generated. However, this germplasm has not undergone any genetic evaluation, and it appears that these valuable genetic resources have been dispersed or lost after the end of the programme (2000). This study aims to investigate the genetic diversity and structure of rescued genotypes currently held in a local collection in Antalaha. Double digest restriction associated-site (RAD)-seq (ddRAD)-seq protocol was applied, providing 865 million read sequences from 56 accessions. The ddRAD sequences have been deposited to the SRA archive of NCBI. From the data, 23,701 filtered concordant common Single Nucleotide Polymorphisms (SNPs) were identified using the three widely used tools (Stacks, BCFtools, Genome Analysis ToolKit - GATK) for short-read library sequencing. These SNPs were used for germplasm evaluation. Clustering analysis segregated samples into five genetic groups: Vanilla planifolia, Vanilla pompona, hybrid Tsitaitra, Vanille Banane and the phenotype Tsivaky. Our analysis revealed distinct subgroups within V. pompona and Tsitaitra, emphasizing the importance of further characterization to accurately reflect the genetic diversity and facilitate better utilization of these accessions in future research and germplasm management. The presence of private alleles in all groups (from 487 to 2866) indicated that populations were diverging and represented a large gene pool that could be useful for future breeding efforts. The genetic data obtained from this study offers valuable insights into the genetic diversity and structure of the vanilla population, with potential applications in breeding and conservation efforts.

The Lecythidaceae family tree, Couroupita guianensis Aubl, popularly known as Nagpushpa, is a widely cultivated ornamental tree with several uses in traditional medicine. The tree is revered as highly sacred in Indian traditional culture due to its uniquely shaped, fragrant flowers. Considering the significance, we were prompted to carry out the metabolite and transcriptome analysis of Nagapushpa. The flower, petals, stamen, stem and leaf of C. guianensis were metabolically profiled, and it was discovered that the flower tissue contained the highest terpenoid reservoir. A number of terpenoid pathway transcripts were also found in the flower tissue after transcriptome profiling. KEGG pathway mapping was carried out to correlate transcript sequences with the biosynthesis of different types of terpenes. We were able to clone three full-length terpene synthase gene candidates, i.e. monoterpene ocimene synthase, diterpene ent-kaurene synthase and sesquiterpene farnesene synthase. The transcript expression of selected terpene synthase genes was also verified in flower tissue. These cloned sequences were used for in silico structural investigations and protein function prediction at the level of 3D structure. The data presented in this study provide a comprehensive resource for the metabolic and transcriptomic profiles of C. guianensis. The study paves the way towards the elucidation of terpene biosynthetic pathway in C. guianensis and heterologous production of useful terpenoids in the future.

The evolutionary relationship between domesticated Oryza species and their wild relatives in North East India is not well understood. To improve the understanding of the evolutionary relationship, this study investigates the genetic diversity of 68 indigenous rice landraces from North East India, ten O. rufipogon genotypes, and nine O. nivara genotypes using chloroplast variable repeat markers which, due to non-recombination and uniparental inheritance, enable better phylogenetic inference. Reference genotypes IR64 (indica) and Nipponbare (japonica) were included to characterize various phylogenetic clusters. Using distance-based hierarchical clustering, model-based structuring and principal component analysis, selected landraces from the three North Eastern Indian states of Assam, Manipur and Arunachal Pradesh were grouped into two phylogenetically different clusters that represented the IR64 and Nipponbare groupings. Interestingly, despite the fact that a cluster analysis combining North East landraces and wild relatives likewise produced two separate clusters (cluster I: Nipponbare, cluster II: IR64), the majority of the wild relatives were only clustered in the IR64 cluster. This suggests that the two distinct evolutionary histories of the rice landraces in North East India are distinguished by their genetic affinity for wild relatives and their variation in the indica and japonica pools. These results highlight chloroplast divergence influencing the genetic diversity of North East landraces with wild relatives. Further, these findings will enable in-depth studies on the functional significance of chloroplast diversity on trait adaptation in rice landraces.