The Southern Andes, especially the inter-Andean valleys of south Bolivia, is thought to be a probable point of domestication within the primary centre of diversity for Andean common beans (Phaseolus vulgaris L.). The national Phaseolus germplasm collection of Bolivia is maintained by the Pairumani Foundation and consists of 449 accessions where most of the accessions are of common bean but some are of related cultivated and wild species. The goal of this study was to determine the genetic diversity of this collection by sampling 174 accessions of P. vulgaris and an outgroup of eight Phaseolus augusti, two Phaseolus lunatus and one Phaseolus coccineus genotype. The genetic diversity and population structure were estimated using 29 microsatellite markers. High levels of polymorphism were found, with a total of 311 alleles identified and an average of 10.7 alleles per marker. Correspondence analysis and an unweighted pair group method with arithmetic mean-based dendrogram distinguished P. vulgaris from the other species of Phaseolus. Common bean accessions were separated into two groups: the first one including Andean controls and most accessions from high altitudes with morphological characteristics and growth habits typical of this gene pool; the second one including Mesoamerican controls and accessions from low altitudes. Inside the Andean gene pool, the wild accessions were diverse and separated from the weedy and cultivated accessions. Low geographical distances between collection sites (up to 100 km) were shown to be related to low genetic distances. These results are important for the conservation of common beans in the Southern Andes.

Centella asiatica (L.) Urban is an important herbaceous medicinal plant with a worldwide distribution. The herb possesses a medicinal value and is used extensively in traditional systems of medicine. The medicinal properties of the herb are attributed to the presence of characteristic triterpenoids and their saponins in the leaves. The major triterpenoids are asiaticoside, madecassoside and their aglycones asiatic acid and madecassic acid, respectively, among others. The present study reports a remarkable qualitative and quantitative variability in secondary metabolites in different accessions of C. asiatica L. as determined by high-performance liquid chromatography (HPLC) analysis. The accessions analyzed in this study can be considered as the core set of discrete chemotypes of C. asiatica. Considerable and contrasting biochemical variations were observed in the terpenoid profiles of the chemotypes. From the basic and applied phytochemical utility, this chemotypic variability in the total content of triterpenoids is important and interesting.

Wild relatives of pigeonpea (Cajanus cajan L.) possess many useful genes that can be utilized for crop improvement, most importantly genes for resistance to Helicoverpa armigera, the legume pod borer. The present study aimed at quantifying diversity in a collection of Cajanus scarabaeoides, Cajanus sericeus, Cajanus reticulatus and C. cajan species selected from a wide geographic range using two PCR-based marker systems, amplified fragment length polymorphism (AFLP) and simple sequence repeats (SSRs), and the hybridization-based restriction fragment length polymorphism (RFLP). Polymorphism was higher among the wild accessions than among the cultivated genotypes. Wild and cultivated Cajanus accessions belonging to different species clustered into four distinct major groups largely based on the interspecific differences. C. scarabaeoides accessions derived from same geographical origins formed one group reflecting similar genetic makeup of these accessions. Dendrograms generated using AFLP, RFLP and SSR marker data were comparable with minor clustering differences, which suggests that either method, or a combination of both can be applied to expanded genetic studies in Cajanus. Mantel testing confirmed the congruence between the genetic distances of three markers, indicating that the markers segregated independently, giving similar grouping patterns of all accessions having similar genetic origin.

The International Crops Research Institute for the Semi-Arid Tropics conserves 335 accessions of Pennisetum glaucum subsp. monodii originated in 13 countries. In the present study, the collection was evaluated and assessed for diversity and geographical gaps. A wide variation was observed in the collection for total tillers per plant (16 to 609), productive tillers per plant (12 to 368), leaf length (21.3 to 58.8 cm) and leaf width (8.1 to 33.1 mm), indicating high fodder yield potential of the collection. The accessions of cluster 3 flowered late, grew tall with thick stems and long and broad leaves, and differed significantly from those of cluster 1 and cluster 2. The accessions of cluster 2 were found to be promising for tillering. The highly significant positive correlation (r= 0.944) between total and productive tillers per plant suggests that the selection for total tillers will result in selection for productive tillers. A total of 354 districts located in 86 provinces of eight countries in the primary centre of origin for pearl millet were identified as geographical gaps. The probability map generated using FloraMap in the present study matched quite closely to the origin of pearl millet, supporting the prediction of P.glaucum subsp. monodii occurrence in the primary centre of diversity for pearl millet. The high fodder yield potential of P.glaucum subsp. monodii germplasm and low intensity of collection in countries under study suggest the need for launching germplasm collection missions, exclusively for pearl millet wild relatives to fill taxonomic and geographical gaps in the collection.

Cinnamomum camphora (Lauraceae) is a well-known multipurpose tree with aromatic oils, insect-repellent effects and ornamental value. In this study, a total of 74,289 simple sequence repeats (SSRs) were found in 56,124 unigenes, of which 14,225 unigenes contained more than one SSR locus. Among these SSR loci, the mono-nucleotide repeats were the most frequent, with a frequency of 61.14%, followed by 24.87% di-nucleotide repeats and 12.87% tri-nucleotide repeats. Twenty-one polymorphic SSR markers were developed and validated in 45 camphor trees. The 21 loci were further examined for cross-species transferability in other six related species. The novel genic-SSR markers will not only benefit genetic diversity analysis and wild resources conservation of C. camphora, but also contribute to exploring the further evolutionary history and genetic differentiation pattern of Cinnamomum.

India is home to some of the oldest civilizations, during which period the local communities domesticated indigenous plant species for food and agriculture and medicinal uses. In this process, they also bio-prospected and/or absorbed potentially valuable exotic plant species, making them integral part of Indian culture, including the traditional medicinal system, the Ayurveda. The present paper discusses the absorption of 26 plant species of exotic origin, before 8th century, as evidenced by archaeological sculptural or botanical remains and documentation of such plants in Sanskrit, the Vedic language. Occurrence and/or introduction of such plants at such distant places in ancient times is visualized as a result of geographical continental fragmentation followed by drift, natural or man-made transoceanic movement, and cultural and trade exchange of plant material over time and space.

Salt stress is a major abiotic stress affecting the productivity of rice crop worldwide. This study screened a set of 71 rice genotypes collected from coastal parts of Goa and Karnataka states in India for seedling stage salinity tolerance to identify genotypes alternative to standard salt-tolerant donors Pokkali, FL478, etc. Phenotyping for seedling stage tolerance was carried out under micro plots at an induced salinity of 12 dS/m. For haplotyping, 14 Saltol QTL linked simple sequence repeat (SSR) markers on chromosome 1 were utilized. On the basis of the response to salt stress, 10 genotypes were found tolerant, 16 moderately tolerant, 29 sensitive and 15 as highly sensitive. Among the SSR markers, marker RM10871 was the most polymorphic with a polymorphic information content of 0.90, exhibiting 14 different alleles followed by RM10793 (0.84) and RM3412 (0.80) with 8 and 7 alleles, respectively. These markers also exhibited high values for the effective number of alleles (Ne) and gene diversity (I). The haplotype analysis revealed that the allelic constitution of the Saltol region of 10 tolerant genotypes from our study varied in comparison to the reference tolerant check FL478. Further, the haplotype of three tolerant genotypes, namely, Goa Dhan 2, Panvel 1 and Goa wild rice (GWR) 005 appears to be completely different from the FL478 haplotype indicating tolerance in these genotypes is controlled by genomic region other than Saltol. These three genotypes with probable novel regions for seedling stage salt tolerance can be considered for enhancing salinity tolerance of rice cultivars.

A total of 27 accessions from ten Vicia species were investigated for flavonoid contents, total polyphenol contents, and DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS [2,2′-azinobis(3-ethylbenzothiazoline 6-sulfonic acid)] free radical-scavenging activities. The results revealed that NAC17 (V. monantha) and NAC14 (V. hyrcanica) had the highest total flavonoid content (1.42 ± 0.09 mg/g) and total polyphenol content [124.2 ± 0.5 μg/gallic acid equivalents (GAE) mg], respectively. Among four flavonoids, naringenin was detected at high concentrations in Vicia species. The DPPH and ABTS assays showed values in the range of 57.2 (IC50) (NAC13, V. faba) to 6530.0 (IC50) (NAC24, V. sativa subsp. nigra) and 19.1 μg/Trolox mg (NAC7, V. cracca) to 253.4 μg/Trolox mg (NAC13, V. faba), respectively. Among ten Vicia species, V. monantha and V. hyrcanica had the highest flavonoid content (1.31 ± 0.09 mg/g) and total polyphenol content (116.5 ± 2.0 μg/GAE mg), respectively. The highest antioxidant activity was detected in V. faba. These results will expand the flavonoid database and provide valuable information on Vicia species for the development of functional foods or feed-additive resources.

A total of 1968 accessions of cultivated eggplants, belonging to Solanum melongena and Solanum aethiopicum and procured from the IVC/JAAS (Nanjing) and IVC/ZAAS (Hangzhou), China, were examined for 23 morphological traits, such as characteristics of plant, stems, leaves, flowers, fruits and original geographic information. A comprehensive numerical classification methodology, including two types of genetic distance, viz. Mahalanobis (Ma) distance and Euclidean (Eu) distance; four clustering methods, viz. unweighted pair group average (UPGA), Ward's (W), complete linkage (CL) and single linkage (SL) methods; three sampling strategies, viz. random (R), preferred (P) and deviation (D); and four sampling sizes (10, 15, 20 and 30% of initial collection), was used to divide all accessions into main groups and subgroups for the establishment of candidate collections. The evaluation of these candidate collections showed that a combination of Eu distance, UPGA clustering method, and R or P sampling strategy with sampling size at 15–20% was suitable for establishing the core collection, providing an adequate and representative genetic diversity of the initial collection of the cultivated eggplants.

Genetic variation in Lactuca serriola, the closest wild relative of cultivated lettuce, was studied across Europe from the Czech Republic to the United Kingdom, using three molecular marker systems, simple sequence repeat (SSR, microsatellites), AFLP and nucleotide-binding site (NBS) profiling. The ‘functional’ marker system NBS profiling, targeting disease resistance genes of the NBS/LRR family, did not show marked differences in genetic diversity parameters to the other systems. The autogamy of the species resulted in low observed heterozygosity and high population differentiation. Intra-population variation ranged from complete homogeneity to nearly complete heterogeneity. The highest genetic diversity was found in central Europe. The SSR results were compared to SSR variation screened earlier in the lettuce collection of the Centre for Genetic Resources, the Netherlands (CGN). In the UK, practically only a single SSR genotype was found. This genotype together with a few other common SSR genotypes comprised a large part of the plants sampled on the continent. Among the ten most frequent SSR genotypes observed, eight were already present in the CGN collection. Overall, the CGN collection appears to already have a fair representation of genetic variation from NW Europe. The results are discussed in relation to sampling strategies for improving genebank collections of crop wild relatives.

Comprehensive screening of rice (Oryza sativa L. subsp. japonica Kato) germplasm resources with different nitrogen (N) efficiency levels is effective for improving N use efficiency (NUE) while reducing pollution and providing high quality, yield, and efficiency agriculture. We investigated 14 indices of 38 varieties under three N application levels to assess differences among genotypes. Rice varieties were classified for screening and identifying N efficient. Descriptive statistical analysis results indicated significant differences in relative yield, and also in NUE indices (agronomic utilization rate and partial productivity of N fertilizer). The genotype main effects and genotype–environment interaction effects (GGE) biplot analysis was used to evaluate suitable varieties, compare the stable and high yield capabilities of different varieties, find the ideal variety, and describe the correlation, discrimination and representativeness of the indices under different N application levels. Descriptive statistical, discrimitiveness and representativeness and factor analysis were used to select indices, in which the panicle number per plant and soil and plant analyzer development (SPAD) value were the key indices for evaluation and identification. Heatmap and hierarchical cluster analysis based on the average value of evaluation indices, and scatter plot based on the comprehensive value of N efficiency (P) according to formula showed that all varieties could be divided into five types under different N treatments. Our findings work toward developing N efficient rice varieties to improve NUE, reduce N fertilizer application and thus N waste, consequently mitigating the effects of rice production on the environment to ensure food security and sustainable agricultural development.

Amphidiploids serve as a bridge for transferring genes from wild species into wheat. In this study, five amphidiploids with AABBUU and AABBNN genomes were produced by spontaneous chromosome doubling of unreduced triploid F1 gametes from crosses between diploid Aegilops (A. umbellulata accessions CIae 29 and PI 226500, and A. uniaristata accession PI 554419) and tetraploid Triticum turgidum (ssp. durum cultivar Langdon and ssp. dicoccum accessions PI 94 668 and PI 349045) species. The composition of high-molecular-weight glutenin subunits (HMW-GS) in these amphidiploids and in their parental A. umbellulata and A. uniaristata species was analysed. As expected, the amphidiploids from T. turgidum ssp. dicoccum accession PI 944668 or PI 349045 and A. umbellulata accession CIae 29 or PI 226500 and A. uniaristata accession PI 554419 showed the same HMW-GS patterns as those of their Aegilops parents, because HMW-GS genes were all silenced in the T. turgidum ssp. dicoccum parents. The amphidiploids from CIae 29 and Langdon inherited all of the HMW-GS genes from their parents except for the Uy type. Using 10 and 15% sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) and 10% urea/SDS–PAGE, 11 Ux and ten Uy types in 16 combinations were observed in 48 A. umbellulata accessions, and two Nx and two Ny types in two combinations were detected in six A. uniaristata accessions. These novel HMW-GS variants may provide new genetic resources for improving the quality of wheat.

trans-Resveratrol (trans-3,4′,5-trihydroxystilbene), a polyphenolic compound uniquely identified in plants, is believed to greatly contribute to human health. Peanut (Arachis hypogaea L.) seeds of 20 germplasm accessions were harvested from the same field and used for resveratrol analysis by high-performance liquid chromatography. trans-Resveratrol content in air-dried peanut seeds was on average about 0.5 μg/g and a statistically significant variation (from 0.125 to 1.626 μg/g, at least a ten-fold difference) was detected among the accessions analysed. The average weight for 100 seeds was 52.84 g. A statistically significant variation in seed weight (from 22.30 to 87.94 g, at least a four-fold difference) was observed. There was no significant correlation between trans-resveratrol content and seed weight. The information about the levels of trans-resveratrol in peanut seeds will be useful for peanut cultivar development and peanut product processing. Breeders could use germplasm accessions containing a high amount of resveratrol to develop new nutritionally improved peanut cultivars and food processors could use these new cultivars to manufacture high resveratrol peanut products.

False brome grass, Brachypodium distachyon (L.) Beauv, has been proposedas a new model species to bridge rice and temperate cereal crops for genomics research.However, much basic information for this species is still lacking. In this study, sixdiploid B. distachyon(2n = 2x = 10)accessions (Bd1-1, Bd2-3, Bd3-1, Bd18-1, Bd21 and BD29) were evaluated for their responseto infestation by two cereal aphid pests of common wheat (Triticumaestivum L.): the greenbug, Schizaphis graminum Rondani, and theRussian wheat aphid (RWA), Diuraphis noxia Mordvilko. Through databasemining of B. distachyon expressed sequence tag (EST) and genomic DNAsequences, 160 EST- and 21 genomic microsatellite markers were developed and used toevaluate genetic diversity among the B. distachyon accessions. All sixaccessions were resistant to RWA biotype RWA1 but showed distinct responses to feeding bygreenbug biotypes C and E, as well as RWA2 RWAs. Although microsatellite-based geneticdiversity among different accessions was generally low, Bd1-1 and BD29 were the mostdiverged from the other four lines. The genetic divergence was correlated withgeographical distances between the Brachypodium accessions. Comparison ofsimple sequence repeat polymorphisms in three inbred lines (Bd2-3, Bd3-1 and Bd18-1) withtheir respective original parental lines revealed no effect of inbreeding on geneticdiversity. Phylogenetic analysis suggested that Aegilops tauschii (Coss.)Schmal., the D genome donor of common wheat, was closer to B. distachyonthan to rice. The greenbug - B. distachyon system seemsto be a model of choice for plant–aphid interaction studies in the grassgenome.

Climate change forecasts point to increased frequency of droughts which may affect plant growth. For protein crops such as lentil, genetic improvement of both water use and drought tolerance is necessary. Wild lentil species are known to have evolved in drought prone areas and can be introgressed into cultivated lentil, making them candidates for the evaluation of high transpiration efficiency (TE) and drought tolerance. We assessed TE, water use and drought tolerance at the plant level for five wild lentil species and in cultivated lentil. Under fully watered and moderate drought conditions, wild lentil genotypes consumed significantly less water to fix similar or more dry matter compared with their cultivated counterparts. Under severe drought conditions, the wild lentil genotype L. ervoides IG 72815 had significantly higher TE compared with L. culinaris Eston. Lens ervoides L-01-827A, had significantly higher yield compared with all other species in the presence or absence of drought and showed significantly higher (α = 5%) TE under moderate drought. Drought susceptibility index was identified as a tool to identify drought-tolerant lentil genotypes grown under severe drought. The numerous small seeds of wild lentil made it difficult to estimate drought indices that are weight based and require formulae that incorporate seed numbers.

Dwarfing genes play an important role in improving yield and adaptability of wheat cultivars in most production environments. Understanding the allelic distribution at dwarfing loci is very important for any wheat-breeding programmes. In this study, we reported the allelic constitution at microsatellite locus Xgwm261 and the two major height-reducing genes Rht-B1 and Rht-D1 among a set of 56 bread wheat cultivars and nine landraces, based on diagnostic polymerase chain reaction assays. With respect to Rht-B1, 37% of the accessions carried the dwarfing allele Rht-B1b, while at Rht-D1, only one accession carried the dwarfing allele Rht-D1b. The allelic state at Rht8 was assayed indirectly by genotyping for the linked microsatellite locus Xgwm261. About 26% of the accessions carried the 192 bp allele (linked with Rht8 gene in some cases), whereas 35 and 12% genotypes carried 165 and 174 bp allele at the microsatellite locus Xgwm261. Cultivars released from 1980 onwards increasingly carried either Rht-B1b or Rht8. This information should allow for a more rational use of this collection for the purpose of wheat improvement in Turkey.

Improving plant resistance against Fusarium wilt (FW) is key to sustaining chickpea production worldwide. Given this, the current study tested a set of 75 FW-responsive chickpea breeding lines including checks in a wilt-sick plot for two consecutive years (2016 and 2017). Genetic diversity analysis using 75 simple sequence repeats (SSRs) revealed a total of 267 alleles with an average of 3.56 alleles per marker. The entire set was divided into two major classes based on clustering method and factorial analysis. Similarly, STRUCTURE analysis placed the 75 genotypes into three distinct sub-groups (K = 3). Marker-trait association (MTA) analysis using the generalized linear model approach revealed nine and eight significant MTAs for FW resistance in the years 2016 and 2017, respectively. Three significant MTAs were obtained for FW resistance following the mixed linear model approach for both years. The SSR markers CESSR433, NCPGR21 and ICCM0284 could be potentially employed for targeted and accelerated improvement of FW resistance in chickpea. To the best of our knowledge, this is the first report on association mapping of the genomic loci controlling FW (Foc2) resistance in chickpea.

We analysed the natural variation of drought response in 11 Tunisian populations of Medicago truncatula sampled from environments that varied in soil composition, salinity and water availability. Plants were cultivated in a greenhouse under well-irrigated and water-deficit treatments (50% of field capacity), and a number of traits associated with drought response were measured. Variance analysis indicated that the variation of phenotypic traits was explained by the effects of population, line, treatment, and population × treatment and line × treatment interactions, with treatment being the one with the greatest effect. A large degree of phenotypic variation for most traits in the two water treatments was found within populations. Most of the measured characters showed higher broad-sense heritabilities (H2) in well-irrigated treatment than in water-deficit treatment. Furthermore, the largest population differentiation (QST) for most of the measured traits was observed under drought stress. Most of the correlations between measured traits under both treatments were positive. Four groups of lines differing in drought tolerance were identified, with 45 susceptible, 14 moderately susceptible, 31 tolerant and 23 most tolerant lines. The tolerant group experienced lowest reductions in the length of plagiotropic axes, length of stems, number of internodes and number of leaves. The large phenotypic variation of M. truncatula in response to drought stress can be used to identify genes and alleles important for the complex trait of drought tolerance.

Drought stress restricts the production of agricultural crops through morphological, physiological and biochemical changes in plants. This study explored the genetic control of physiological traits related to drought in coriander. In a diallel analysis, all six parents, their 15 F1 hybrids and 15 F2 populations were subjected to different irrigation regimes including well-watered, mild and severe water deficit stress. Drought stress decreased the relative chlorophyll content (RCC), the relative water content (RWC), chlorophyll a (Chla), chlorophyll b (Chlb), total chlorophyll (TChl) content, carotenoids (Car) and essential oil yield (EOY) in F1 and F2 generations. General combining ability (GCA) and specific combining ability effects were highly significant for all traits in F1 and F2 generations. Additive gene action was predominant for Chla, Chlb, TChl and Car under well-watered condition while non-additive gene effects were more important under mild and severe water deficit stresses in F1 and F2 generations for the above traits. Additive gene effects were more important for RCC, RWC and electrolyte leakage (EL) traits in both F1 and F2 generations under mild and severe water deficit stresses. In conclusion, the high narrow-sense heritability and significant genetic correlations between EOY and RCC, RWC and EL suggest that these traits can be used as surrogates to identify superior genotypes for arid and semi-arid regions. Also, the parental lines, P4 and P6 had the best GCA for RCC, RWC, Chla, Chlb, TChl, Car, essential oil content and EOY.

International Institute of Tropical Agriculture maintains 2544 cassava accessions (Manihot esculenta Crantz) from 28 countries in its field bank. Being vegetatively propagated, this poses challenges in maintenance in terms of cost as well as in labour requirements. A core collection representing the range of phenotypic diversity present in the entire collection would enhance the conservation aspects and increase the potential for its exploitation in crop improvement programmes. The present study aimed to establish a core collection using 40 agro-morphological traits evaluated at two locations using a different number of accessions in each location. To meet the challenges generated by the types of variables and include maximum diversity in the core collection, a sequential strategy based on five major concepts was used: hierarchical multiple factor analysis allowing the mixture of variables of different kinds; three-way analysis that included the effect of genotype × environment interaction in the clustering process; linear discriminant function to assign all those individuals who were included in one location but not in the other to the groups that were generated from the common number of accessions evaluated in both locations; and D-allocation method to select samples from each cluster. The representativeness of the core subset to the entire collection was further estimated by comparing means and variances, range, and distances between accessions. The established cassava core collection consisted of 428 accessions that conserved 15% higher phenotypic diversity with no redundancies. The phenotypic diversity represented in this core collection will be a guide to users of cassava germplasm in their crop improvement programmes.