A set of 146 representative adzuki (Vigna angularis var. angularis and var. nipponensis) germplasm from six Asian countries with a tradition of adzuki bean production, together with an outgroup standard rice bean (Vigna umbellata), were analysed by amplified fragment length polymorphism (AFLP) methodology using 12 informative primer pairs. A total of 313 unambiguous polymorphic bands were created. According to the dendrogram, using cluster analysis based on AFLP banding, 143 of the accessions were distinct and revealed enough genetic diversity for identification and classification of accessions within Vigna angularis. A neighbour-joining tree was generated using the newly developed Innan's nucleotide diversity estimate from the AFLP data. From analysis, seven distinct evolutionary groups, named ‘Chinese cultivated’, ‘Japanese cultivated’, ‘Japanese complex-Korean cultivated’, ‘Chinese wild’, ‘China Taiwan wild’, ‘Nepal- Bhutan cultivated’ and ‘Himalayan wild’, were detected. Nucleotide diversity with geographical distribution of each group is discussed, regarding the evolutionary relationships between wild and cultivated adzuki beans. The preliminary results indicated that cultivated adzuki beans have been domesticated from at least four progenitors with at least three geographical origins.

This paper examines genetic erosion in rice landraces thriving in traditional smallholder agricultural systems in the Sarangani uplands, Philippines. In these marginal areas, the crop is closely interwoven with tribal culture and is vital in ensuring food security among upland households. Field visits unveiled high varietal diversity for upland rice and a rich tapestry of indigenous knowledge associated with its cultivation and use. Study results, however, revealed the tapering of the crop's genetic base due to farmers' changing priorities, pest infestation, weakening seed supply systems, shift to cash crops, natural calamities, environmental degradation, government programmes and peace and order problems. Consequently, these pressures undermined traditional agricultural systems in Sarangani upland communities causing food and water scarcity, hunger and suffering on a catastrophic scale. Interdisciplinary strategies aimed at simultaneously averting further varietal losses and environmental degradation while improving human well-being are therefore warranted. Furthermore, making traditional rice farming a lucrative endeavour will induce the younger generation to remain in the uplands and choose farming as a profession. This way, biocultural restoration of agriculture will be attained and the continued presence of the tribal groups in the Sarangani uplands will be ensured for a very long time.

Phenotyping of genetic resources remains the bottleneck in the characterization of genetic resources, since the advent of modern next-generation sequencing technologies has made genotyping much more cost- and time-effective. This article reports on the phenotyping of agriculturally important traits in perennial ryegrass (Lolium perenne). In the present study, water-soluble carbohydrate (WSC), crude protein and dry matter contents were recorded for 1320 individuals, pooled into 132 samples from 33 perennial ryegrass ecotypes and cultivars at five different harvest time points across the 2004 growing season. While, in general, the cultivars had higher WSC contents than the ecotypes, individual ecotypes did show potential to be used in breeding programmes, as they had higher values than all other accessions at particular cutting time points. In correlation analyses, positive relationships were observed between dry matter and glucose contents both early and late in the growing season. Principal components analysis allowed the split either between cultivars and ecotypes or between tetraploid cultivars and the rest of the accessions at four of the five cutting time points. In the analysis of variance, cutting time was the most significant factor influencing the variation in traits.

Variety selection from locally adapted crops is the major climate change adaptation strategy of farming communities. There are several justifications for re-thinking for the sustainable use of crop biodiversity in our breeding programs. Thirty-one durum wheat farmers' varieties (FVs), together with five improved check varieties, were characterized in Tigray during 2014 and 2015 main cropping seasons. The genotype effect explained most of the variations in measured traits, which enabled us to identify superior and stable genotypes for wider adaptation as well varieties with more local adaptation. The genotypes and test locations imposed a highly significant (P < 0.001) effect on both phenological and quantitative traits. A yield advantage of 14.3% was obtained from top performer FV over top performer improved variety, Asassa. Of the tested FVs, 27.8% were superior for grain yield (GY) than improved varieties and 19.4% of these superior FVs were more stable and adaptable than the improved varieties. Besides giving higher GY with spatial stability, they qualify for industrial requirements with high-grain protein (>13%) and gluten (>33%) contents. FVs such as G10, G16, G21, G22 and G30 have wider adaptability and are suitable for production in all tested areas. As outcome of this study, two superior FVs, G10 (208304) and G30 (8208), were nationally released for commercial production for their productivity, stability and grain quality. Utilizing the diverse durum wheat FVs can effectively improve productivity and adaptability. Wheat breeders need to revisit these resources to improve adaptation of wheat production to the changing climatic conditions.

Genetically accessible variation to some of the abiotic and biotic stresses are limited in the cultivated lentil (Lens culinaris Medik.) germplasm. Introgression of novel alleles from its wild relative species will be useful for enhancing the genetic improvement of the crop. L. ervoides, one of the wild relatives of lentil, is a proven source of disease resistance for the crop. Here we introduce a lentil advanced backcross (LABC-01) population developed in cultivar ‘CDC Redberry’ background, based on L. ervoides alleles derived from an interspecific recombinant inbred population, LR-59-81. Two-hundred and seventeen individuals of the LABC-01 population at BC2F3:4 generation were screened for the race 0 of anthracnose (Colletotrichum lentis) and stemphylium blight (Stemphylium botryosum) under controlled conditions. The population showed significant variations for both diseases and the transfer of resistance alleles into the elite cultivar was evident. It also segregated for other traits such as days to flowering, seed coat colour, seed coat pattern and flower colour. Overall, we showed that LABC-01 population can be used in breeding programmes worldwide to improve disease resistance and will be available as a valuable genetic resource for future genetic analysis of desired loci introgressed from L. ervoides.

Salvia (sage) is the most important and largest genus of the Lamiaceae family. High similarities among species in this genus lead to difficulty in its systematic identification. Despite its economic importance, limited molecular studies have been conducted to evaluate the genetic diversity among and within Salvia species. In this study, SRAP (sequence-related amplified polymorphism) markers, which targeted ORFs (open reading frames) as functional regions in the genome, were used to detect the genetic diversity of five Salvia species (S. virgata Jacq., S. nemorosa L., S. officinalis L., S. cereal L. and S. sclarea L.). Fourteen primer combinations (PCs) were amplified by 265 fragments on 54 genotypes, in which 255 (96%) were polymorphic. The average polymorphism information content (PIC) value was 0.308 over all PCs. The genetic distance among species ranged from 0.126 (between S. virgata Jacq. and S. nemorosa L.) to 0.568 (between S. nemorosa L. and S. sclarea L.). Based on Jaccard's similarity coefficient and UPGMA algorithm, cluster analysis separated different species (r= 0.920). The results showed high genetic differentiation (Fst= 0.337) and negligible gene flow (Nm= 0.750) among species. Owing to the high genetic variation among and within Salvia species, it serves as a rich source of germplasm with potential for use in breeding programmes.

Sheath blight caused by soil borne necrotrophic fungus Rhizoctonia solani [teleomorph-Thanatephorus cucumeris (Frank) Donk.] is a major disease of rice. The disease is increasing over the year in India and cause up to 69% yield loss under favourable conditions. A total of 67 accessions of Oryza nivara were screened to identify resistance against sheath blight during 2015. Out of these, 16 accessions were found moderately resistant (MR) which were further evaluated during the year 2016 and 2017. After three years of screening, 12 of them were found to have a consistent moderate resistant reaction whereas four of the O. nivara accessions namely, IRGC81941, IRGC102463C, CR100097 and CR100110A have shown moderately susceptible to susceptible reaction against sheath blight. A correlation study revealed that different disease variables measured were significantly (P < 0.05) correlated. All the genotypes and genotype × environment interaction had a significant (P < 0.001) effect on all the disease variables. Cluster analysis showed that all the accessions were clustered into four groups which showed resistant, MR, moderately susceptible and susceptible reactions. Among all the O. nivara accessions IRGC81941A showed the maximum potential against sheath blight due to a least relative lesion height of 22.80%. None of the accession had complete resistance to the disease. The identified promising accessions such as IRGC81835, IRGC81941A, CR100008 and CR100111B can be utilized in a sheath blight resistance breeding program.

The study of the genetic structure of cultivated plant populations maintained by farmers is of great importance for evolutionary and conservation biology. Such studies help understand the bases of crop evolution and conservation in relation to farmers' practices. In this study, we assessed the genetic structure underlying landrace diversity of dry-season sorghum. This crop constitutes a historical model of innovation developed by farmers to extend sorghum cultivation to the dry season. Two types of dry-season sorghum are cultivated. We aimed to assess the link between farmers' taxonomy and molecular genetic structure. We collected both types of dry-season sorghum in two villages of northern Cameroon which represented 20 landraces. These landraces were genotyped using eight polymorphic microsatellite markers. This study compared two clustering methods: a Bayesian method (STRUCTURE) which is based on explicit genetic assumptions and the discriminant analysis of principal component method. The latter, more recently proposed, is based on the combination of principal component analysis and discriminant analysis. We noticed a general congruence between these two methods. We also used both methods to infer the genetic structure of our sample. Our results showed strong genetic structuring of the landraces, with K= 14 genetic clusters. We then analysed the fit between farmers' taxonomy and genetic structure. The data suggested that each type and each landrace corresponds to a given genetic entity. This pattern was robust across both villages, despite differences in cultural practices.

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.

Germplasm accessions of wild Lactuca species are maintained worldwide in ex situ collections as gene reservoirs for quality and disease resistance traits for cultivated lettuce. Accessions of 12 Lactuca species from 6 genebanks were compared via morphological characterization and AFLP (Amplified Fragment Length Polymorphism)-based profiling to estimate the extent of duplication. A method of assessing redundancy within very similar, but not identical accessions, is proposed, based on 352 polymorphic AFLP products. Seven duplication groups showed a high level of AFLP similarity, and one pair of Lactuca saligna accessions displayed identical AFLP profiles. In several cases, the morphological assessment indicated that a taxonomic reclassification of accessions was necessary. Candidate duplicates were identified using population parameters and inter- and intra-accession variability. The implications of these findings on the conservation of wild species are discussed.

This article links the concept of access and benefit-sharing as it pertains to crop genetic resources to climate change adaptation and argues that systems for access and benefit-sharing can, and should, be designed to contribute to climate change adaptation for agriculture. The access and benefit-sharing provisions of the two international agreements that together provide the international legal framework for access and benefit-sharing – the Convention on Biological Diversity (with its Nagoya Protocol) and the International Treaty on Plant Genetic Resources for Food and Agriculture – are presented and analysed. How these agreements are implemented is central to adaptation, as the effects of climate change threaten crop genetic resources and future adaptive capacity, and, if properly maintained and utilized, crop genetic resources will be essential to climate change adaptation across the globe. This article, therefore, argues that an important adaptation strategy linked to such implementation is to direct benefit-sharing for crop genetic resources towards adaptation efforts and to ensure facilitated and efficient access to crop genetic resources for adaptation purposes. Some options for how this can be pursued at both the international and national level are offered.

Recombinant inbred lines (RILs) generated from a cross between a cultivated species and its wild progenitor species serve as important germplasm for introgressing valuable genes from a wild species to a cultivated species. During this breeding process, it is equally important to prevent the loss of agronomically important genes in the cultivated species. In an effort to establish an efficient selection system for the single Rsv1 gene conferring durable resistance to soybean mosaic virus (SMV) in the soybean cultivar Hwangkeum (also known as Suweon 97), which is a parent of a RIL population from Hwangkeum (cultivated soybean) × IT182932 (wild soybean), in the present study, we unexpectedly identified an additional necrosis-conditioning gene unmasked by a recombination in the middle of the Rsv1-containing nucleotide-binding leucine-rich repeat gene cluster region and the Rsv3 gene in Hwangkeum. Thus, Hwangkeum contains at least three SMV resistance genes consisting of two tightly linked genes at the Rsv1 locus and the Rsv3 locus. The results of this study provide additional important information for use of the Hwangkeum genome in soybean breeding programmes.

Cotton is one of the most important crops among natural fibres. Fibre quality determines the spinning ability, which is negatively correlated with yield and yield-contributing traits. Limited efforts have been made to improve fibre quality and yield in diploid cotton. Therefore, screening a large panel of germplasm lines can help identify genotypes with better fibre quality and yield. We evaluated 712 desi cotton genotypes for fibre quality traits. The genotypes showed a significant difference for all the traits, suggesting considerable variability for fibre quality improvement. Fibre length and strength showed high phenotypic and genotypic coefficients of variation. Heritability was high for fibre strength, length, and elongation. Fibre length and strength were positively correlated; however, micronaire was negatively correlated with these two traits. Superior accessions were identified for fibre length (11), strength (20), uniformity (7), and elongation (25) among genotypes. Most of the desi lines (71%) had medium micronaire values. Twenty accessions identified were ideal for spinning, showing the fibre strength-to-length ratio of one. Cluster analysis based on Euclidean distance grouped all 712 accessions into four major clusters. Principal component analysis biplot revealed that accessions AC3418, 360-SP1, AC3522B, Kanpur A, Gao16CB-9, and AC3370 were genetically diverse. The superior accessions for fibre quality identified in this study are potential lines for the diploid cotton improvement programme.

The present research was conducted to determine the reactions of 200 pure lines selected from bread wheat landraces collected from 18 provinces and seven regions of Turkey against bunt disease (Tilletia foetida) under field conditions for 3 years. Bunt disease reactions of pure lines were assessed based on the infected spike/total spike ratio. For visually assessed materials, the GGE-biplot method, where G = genotype effect and GE = genotype-by-environment effect, was used to group the reactions against bunt disease. Fifty-nine pure lines showed high resistance (with infection rates ranging from 0.1 to 10%); 24 in the moderate resistance (with infection rates ranging from 10.1 to 25%); 75 in the moderate susceptibility (with infection rates ranging from 25.1 to 45%); 38 in the susceptibility (with infection rates ranging from 45.1 to 70%) and finally four in the highly susceptibility (with infection rates of >70.1%). PC1 and PC2 of the GGE-biplot graph created over the years explained 76.49% of the total variation. The GGE-biplot graph provided efficient identification of resistant genotypes. The lowest PC1 values and PC2 values close to 0.0 explained the resistance of pure line to bunt disease best. The resistance of pure lines to bunt disease over the biplot decreased from the first section through the last section. Based on the results of present study, 19 pure lines (located within the first circle of the biplot graph) were selected for resistance breeding programmes against the diseases.

Sustainable utilization of plant genetic resources for food and agriculture has been increasingly discussed at both national and international forums. Besides exploitation, conservation of plant genetic resources has become an integral part of these discussions. Conservation aims at maintaining the diversity of living organisms, their habitat and the interrelationship between organisms and their environment. For achieving such goals, appropriate conservation strategies have to be adopted. Determining the genetic makeup of a particular plant species is of critical importance when planning a suitable conservation strategy. In this study, we sequenced the chloroplast trnK intron, matK and rbcL gene aimed at understanding the rarity of Nymphaea tetragona, a critically rare and endangered plant of India found at only one location. We extended our investigation to other Nymphaea species such as N. nouchali, N. pubescens and N. rubra that are commonly available throughout India. Interestingly, matK gene of N. tetragona revealed high number of non-synonymous substitutions. Molecular evolutionary analysis indicated that three of these sites may be under mild selective pressures. Such adaptive changes at the DNA and protein sequence level of matK gene may have been associated with the colonization of N. tetragona, suggesting that it could have migrated from China.

The importance of plant genetic resources for the future of agricultural production and for achieving food security necessitates the study of the factors affecting their most efficient exploitation, particularly in breeding programmes. The established negative correlation between competitive and yielding ability is emerging as an important, yet overlooked cause of seed and variety degradation. Because of this negative correlation, the low yielding, strong competing plants within the variety or the germplasm under study acquire a survival advantage over the high yielding, weak competing plants when propagated under dense stands, leading to a gradual cultivar degeneration and identity loss. Moreover, this gradual degeneration prevents selecting for the positive and novel adaptive variation that is endlessly released by the genome in response to biotic (e.g. mutating pathogens) and abiotic stresses. The application of nonstop selection on individual plants grown in the absence of competition using a novel selection equation demonstrates an effective means to counteract the negative effects and accelerate progress through selection.

The pattern of inheritance of powdery mildew resistance expressed by two bread wheat (cultivar ‘Alcedo’)/Aegilops markgrafii introgression lines was explored using F2 populations bred from crosses made with the powdery mildew-susceptible cultivar ‘Kanzler’. Disease reaction was tested at both seedling and adult plant stages. Two resistance loci, designated QPm.ipk-1A and QPm.ipk-7A, were identified as mapping to the distal ends of chromosome arms 1AS and 7AL, respectively. Whereas QPm.ipk-1A was expressed throughout the plant's life, QPm.ipk-7A was only effective at the seedling stage. The map location of both resistance loci indicated that resistances originated from A. markgrafii. The possible genetic relationship of these disease-resistant genes to known Pm genes is discussed in the context of synteny.

Genebanks play an important role in the conservation of global plant biodiversity. The European Search Catalogue for Plant Genetic Resources (EURISCO) was created as a central entry point to provide information on these collections. However, a major challenge lies in the heterogeneity of scientific plant names. This makes the selection of suitable plant material, e.g. for research or breeding purposes, significantly more difficult. For this reason, the taxonomic backbone of EURISCO has been completely revised. Search terms entered by users are now automatically checked against taxonomic reference repositories, allowing a variety of synonyms to be identified. In addition, a fuzzy search has been implemented, which makes the search function tolerant of erroneous data (e.g. caused by typing errors). Besides improvements of the search interface, more support will be given to EURISCO's data providers. The new developments provide a tool that makes it easier to identify problem cases within the data, such as accepted/non-accepted taxonomic names, and will successively improve the quality of taxonomic information in EURISCO.

A selection of tomato (Solanum lycopersicum L.) genotypes with diverse origin and breeding history including 33 landraces, eight modern varieties and two commercial hybrids has been characterized using a set of 25 qualitative descriptors and six quantitative traits. A wide range of variation was evident for the majority of traits, highlighting their utility for characterizing tomato germplasm collections. A plethora of qualitative traits including type of leaf blade, depression and ribbing at peduncle end, fruit shape at blossom end, number of locules and flowering time, as well as measured traits with economic importance such as fruit fresh weight, firmness and total yield per plant, were found to be highly variable within the collection, with a diversity index greater than 0.8. Strong correlations were detected among several traits related to fruit yield and quality. Two-dimensional principal component analysis as well as the unsupervised hierarchical clustering grouped genotypes according to their phenotypic resemblance and morphological characteristics to a great extent. Landraces from different origins were scattered across the whole variation spectrum of PC1 and PC2. A set of six qualitative traits could efficiently discriminate cultivars in PCA (explaining 75% of total variation), suggesting that it can serve as a valuable breeding tool for the germplasm characterization. The evaluation of the phenotypic diversity in the collection as well as the identification of traits that contribute most to heterogeneity have important implications for establishing core collections with high diversity, as well as designing breeding schemes across the Mediterranean basin.

Licorice (Glycyrrhiza glabra) is an important medicinal herb and has long been used in traditional medicine for the treatment of several diseases worldwide. Understanding the genetic diversity within Glycyrrhiza species is important for the efficient conservation of these medicinal herbs. In this study, we have developed 20 polymorphic chloroplast microsatellite (cpSSR) markers using the chloroplast genome of G. lepidota. The cpSSR markers were tested on a total of 27 Glycyrrhiza individual plants. The number of alleles per locus ranged from two to eight among the Glycyrrhiza accessions. Overall, the Shannon index (I) for each cpSSR ranged from 0.315 to 1.694, the diversity indices (h) were 0.140–0.793 and the unbiased diversity indices (uh) were 0.145–0.825. In addition, the cpSSR markers were successfully divided and classified the 27 Glycyrrhiza individuals into four groups. The cpSSR markers developed in this study could be used in the assessment of genetic diversity and rapid identification of Glycyrrhiza species.