The North East Hill Region (NEHR) of India is home to diverse maize landraces including pigmented accessions rich in antioxidants and nutritional properties. The present study attempted to characterize a representative collection of this mostly unexplored diversity. Altogether eighty-three local maize landraces from the seven hill states of the NEHR were studied with special emphasis on pigmentation diversity. For the morphological traits, a significant ANOVA indicated the presence of substantial genetic variability for which selection would be fruitful. A number of these accessions were found to have traits that help cope with moisture stress, improve stalk strength and optimize photosynthesis. Principal component analysis studies for the yield attributing traits indicated that ear weight was most variable. The bleaching/histological studies confirmed that anthocyanin pigment when present was always restricted to the aleurone layer of the kernels, typical of blue maize. Quantitative analysis for kernel anthocyanin/phlobaphene content also revealed genetic differences among the accessions. Genetic analysis using the model-based STRUCTURE indicated significant population structuring among the accessions. Specifically, for the pigmentation diversity studies both principal coordinate analysis and neighbour joining methods revealed near concurrent population structuring due in part to the high differentiation of seven of the twenty-one pigmentation specific loci studied. The results obtained provide comprehensive evidence of a significant amount of genetic differentiation among the landraces under study. Landraces are valuable reservoirs of favourable alleles for which selection can be made and, as in this study, identify accessions for breeding maize with enhanced levels of beneficial secondary metabolites.

Tetraploid wheat species from Ethiopia hold ample genetic variation, which could provide a source for improvement of wheat. A total of 196 Ethiopian tetraploid wheat (Triticum turgidum spp.) accessions, including 174 landraces and 22 improved cultivars, were evaluated at Sinana and Debrezeit to assess morphological variation, genetic advance, heritability and correlation based on 11 phenotypic traits. Except for spike length, highly significant variation (P < 0.001) among genotypes for all traits was observed. The observed mean and range values of the phenotypic traits revealed high variability in the accessions. Phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) values were high for grain yield, biomass yield and harvest index. Seed yield showed highly significant (P < 0.001) negative correlation with days to booting and days to maturity and positive correlation with all traits. The estimates of heritability (H2) for grain yield and the number of spikelets per spike respectively ranged from 41.78 to 84.62%. The genetic advance as a percentage of mean was low for the number of seeds per spikelet, days to booting and days to maturity; intermediate for plant height, thousand kernel weight and spike length and high for the number of spikelets per spike, the number of effective tillers per plant, grain yield, biomass yield and harvest index, respectively. The number of spikelets per spike gave a high value of genetic advance and heritability implying high genetic gain from its selection.

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.

Rice cultivation in hills is challenged by sub-optimum weather conditions, low soil fertility, low temperature and moisture stress which impedes in attaining high productivity. To address this, four studies were carried out at ICAR Sikkim Centre, Gangtok, India to evaluate relative performance of local organic cultivars and conventionally bred varieties under an organic farming system. Conventionally bred varieties yielded significantly higher (45%) than local cultivars under recommended timely sown conditions whereas local cultivars showed superiority in grain yield under late sown conditions coinciding with low temperature during flowering to grain filling. Genotypes did not show significant interaction when organic or conventional production conditions were compared. For grain yield, there was a significant variation for variety × year interaction under organic system. Local organic cultivars had reduced grain yield and associated traits under rainfed upland conditions. Panicles per unit area had a significant positive association with grain yield in all production environments (organic lowland, organic upland, conventional lowland and conventional upland). Overall, the study indicates using local cultivars as donors for specific stress tolerance traits in background of high yielding genotypes to enhance rice yields sustainably under organic system in hills.

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.

The characterisation of traditional barley varieties from North Africa is promising with respect to detect traits linked with resilience to drought. Nine Algerian barley varieties comprising the economically relevant local landraces Saïda183 and Tichedrett were genotyped by random amplifying polymorphic DNA (RAPD) and by Simple Sequence Repeat (SSR) markers to get insight into their phylogenetic relationship and to compare the efficiency of the two approaches. The SSR markers were chosen such that all chromosomes of barley were represented by at least one marker. In addition, a principal component analysis (PCA) of morpho-agronomical traits was conducted. We found that the phylogeny based on the RAPD markers reflected the geographical distribution of the tested varieties, while the phylogeny based on the SSR markers reflected the pedigree. Among the RAPD markers, the maximal polymorphism information content was obtained for BY14 with a value of 0.82, for the SSR markers, Bmg13 was most informative with a value of 0.60. The similarity matrix used to the construct the phylogenetic tree, inferred a close relationship (Jaccard Index 0.8 based on RAPD markers) between the accessions Fouara and Oued-Athmania occurring in close vicinity. The SSR markers group the autochthonous varieties Saïda183 and Tichedrett together with a Jaccard Index of 0.8. The close phylogenetic relationship between Saïda183 and Tichedrett is also supported by the PCA of morphological and agronomic traits. Our data underpin the diversity of Algerian barley varieties and lend support to the autochthonous origin of these two Algerian landraces.

Grapevine (Vitis vinifera L.) is a major worldwide crop of high economic importance, tightly interwoven with the traditions and the culture of many civilizations. The Greek vineyard is one of the oldest in the world composed of an ample number of highly diverse indigenous landraces. However, over the last decades the local cultivated grapevine germplasm has undergone a drastic reduction of diversity, due to the established market preferences for international varieties. In the current work a combined approach involving both, ampelographic traits and microsatellite markers has been undertaken, to study the genetic diversity within and among 96 grapevine genotypes belonging to 36 V. vinifera subsp. vinifera cultivars, predominantly representing autochthonous Greek landraces. Results revealed high genetic diversity for the Greek cultivars yielding a mean number of alleles per locus 14.69 and mean polymorphic information content 0.848. Hierarchical cluster analysis, employing both, ampelographic and microsatellite data, showed a clear distinction based on the origin of the germplasm; Anatolian versus Mediterranean. Principal component analysis, based on the most informative ampelographic traits, coupled to the results from genetic structure analysis further corroborated the proposal of germplasm differentiation on the basis of geographic origin. This information can be further utilized for the reconstitution of the Greek vineyard and can significantly contribute towards a rational conservation and utilization strategy for breeding or for direct cultivation of the Greek indigenous grapevine germplasm.

Anthracnose or fruit rot disease caused by Colletotrichum spp. leads to substantial economic losses in chilli (Capsicum annuum L.) production worldwide. In the present study, 24 different Bhut Jolokia chilli landraces and seven Capsicum annuum cultivars have been collected from the northeastern region of India and subsequently screened under in vitro and in vivo conditions against Colletotrichum capsici and C. gloeosporiodes infections. During field evaluation, eight chilli genotypes (CC0164, CC0165, CC0191, CC0192, CC0202, CC0206, CC0209 and CC0218) were highly resistant and 12 genotypes (CC0154, CC0179, CC0181, CC0183, CC0186, CC0189, CC0193, CC0198, CC0205, CC0210, CC0213 and CC0217) were found in resistant category against C. capsici infection. During in-vitro germplasm evaluation, 11 and 12 landraces were found to be highly resistant to C. capsici and C. gloeosporioides infections, respectively. According to the findings, the majority of Bhut Jolokia chilli landraces are resistant to anthracnose. Given the difficulties farmers experience as a result of excessive use of fungicides and pesticides, germplasm screening for host resistance has already begun. The resistant lines identified in the current study offers better choices to tackle anthracnose and could be used effectively in breeding programs to develop anthracnose resistant varieties.

The flag leaf acts as a functional leaf in rice, Oryza sativa L., primarily supplying photosynthate to the developing grains and influencing yields to a certain extent. Drought stress damages the leaf physiology, severely affecting grain fertility. Autumn rice of northeast India is called locally as ‘ahu’ rice, and is known for its drought tolerance. Exploring diverse germplasm resources at the morphological level using an association mapping approach can aid in identifying the genomic regions influencing leaf shape dynamics. A marker–trait association (MTA) study was carried out using 95 polymorphic SSR markers and a panel of 273 ahu rice germplasm accessions in drought stress and irrigated conditions. The trials suggest that at the vegetative stage, drought stress significantly affects leaf morphology. The leaf physiology of some tolerant accessions was relatively little affected by stress and these can be considered as ideal varieties for drought conditions. The phenotypic coefficient of variance and genotypic coefficient of variance values implied moderate to high variability for the leaf traits studied. Analysis of molecular variance inferred that 11% of variation in the germplasm panel was due to differences between populations, while the remaining 89% may be attributed to a difference within subgroups formed through STRUCTURE analysis. Using the mixed linear model approach revealed 11 MTAs explaining between 4.5 and 20.0% of phenotypic variance at P > 0.001 for all the leaf traits. The study concludes that ahu rice germplasm is extremely diverse and can serve as a valuable resource for mining desirable alleles for drought tolerance.

Any relative nutritional differences among the diverse maize (Zea mays L.) landraces traditionally maintained in the Greater Southwest are little understood. In this article, we investigate a range of nutritional traits of five indigenous maize landraces in the US Southwest based on different kernel endosperm types: pop, flour, flint, dent, and sweet. We present macronutrient and micronutrient values for accessions of each landrace grown in the same environmental grow-out experiment. Macronutrient values vary considerably across these endosperm accessions. Sweet and flour maize had higher values of fat and protein, whereas dent had the highest carbohydrate content. Sweet and flour maize were comparatively the best sources of micronutrients. Sweet maize yielded the highest values of potassium, thiamin, and magnesium, and flour kernels had the highest riboflavin and niacin content. These results indicate that the maintenance of diverse maize landraces had nutritional as well as ecological, symbolic, and culinary value in both the past and today. Compared to modern commercial maize standards, traditional southwestern maize landraces had a somewhat higher caloric value, many had higher vitamin and mineral content, and all accessions but dent displayed higher protein values. This suggests that southwestern maize-focused diets that included diverse landraces may have been more nutritious than previously understood.

Melon (Cucumis melo L.) is an economically important vegetable crop worldwide. Karnataka state of southern India is rich in melon landraces and wild relatives, which are potential sources of genetic diversity for crop improvement. Here we report on the collection, characterization and documentation of previously unexplored landrace and wild material to broaden the availability of this genetic diversity for use in melon improvement. Accessions of botanical groups, momordica, kachri, chandalak, reticulatus, acidulus and indicus, intermediate forms of acidulus and momordica, and three melons of an unknown group were sourced directly from farmers of eight agro-ecological regions. Twenty-three representative melon landraces and wild relatives, along with four reference varieties of different botanical groups, were evaluated for agronomic traits during the year 2016. Very wide and distinctive genetic variations were observed among the melon accessions for ovary characters, sex expression, days taken to first fruit maturity, external and internal fruit traits, and fruit cracking (splitting). The remarkable variability displayed among the melon accessions as observed from the study demonstrates the importance of them as a valuable genetic reservoir for melon improvement.

The Sikkim-Himalaya represents one of the unique reservoirs of rice genetic resources in India owing to the presence of a large number of landraces adapted to extreme climatic and edaphic conditions. This valuable gene pool is now under threat due to the introduction of high-yielding varieties, wanting suitable genetic intervention for enhancing their productivity, and thus economic viability. Development of lodging resistant, high-yielding varieties tolerant to soil acidity through association mapping aided marker-assisted breeding programmes can help achieve this in a fast and efficient manner. But this requires information on genetic diversity, population structure, etc., of the germplasm collection, which is strikingly lacking. We, therefore, characterized a set of 53 rice landraces from Sikkim to address the above issues. The results revealed moderate diversity, poor divergence and high gene flow in our germplasm collection attesting its utility as an association mapping panel. Further, a total of 115 putative marker-trait associations (P < 0.05, R2 ≥ 10%) were obtained using the general linear model and mixed linear models of which 25 were identical in both. Some of the associated markers were positioned in those regions where Qualitative Trait Loci have been previously identified in rice, providing credence to our results. The resources generated from this study will benefit the rice breeders from this region and elsewhere for targeting the yield and related traits, in addition to conservation efforts by the interested researchers.

The current study was undertaken to identify the sources of tolerance to bruchid in cowpea, by screening a set of germplasm accessions as a source for natural resistance. A total of 103 diverse accessions of cowpea were evaluated for resistance to Callosobruchus maculatus Fab. under no-choice artificial infestation conditions. Significant differences among the cowpea accessions were observed for oviposition, adult emergence, exit holes and per cent seed weight loss (PSWL) caused by the bruchid infestation. The accessions showed variation in physical seed parameters viz., colour, shape, testa texture, length, width and seed hardness. Among the seed biochemical parameters studied, per cent sugar content ranged from 0.322 (IC330950) to 1.493 (IC249137), and per cent phenol content ranged from 0.0326 (EC390261) to 1.081 (EC528423). Correlation studies indicated that PSWL had significant positive correlation (r = 0.335) with exit holes, oviposition (r = 0.219), adult emergence (r = 0.534) and seed roundness (r = 0.219). Adult emergence had a significant negative correlation with seed hardness (r = −0.332). Correlation with biochemical parameters indicated that PSWL had a significant positive correlation (r = 0.231) with sugar content and a significant negative correlation with phenol content (r = −0.219). None of the accessions were found to be immune to bruchid infestation. However, out of studied accessions, EC528425 and EC528387 were identified as resistant based on PSWL and moderately resistant based on adult emergence. These resistance sources of cowpea germplasm can be used as potential donors for development of bruchid tolerant/resistant cultivars.

Fonio (Digitaria exilis (Kippist) Stapf) and Bambara groundnut (Vigna subterranea (L.) Verdc.) are native crops grown at a small scale in Mali that have potential to support agricultural productivity under climate change. A community biodiversity management approach was explored in this study as a means to reinforce the cultivation of these crops by increasing farmers' access to intraspecific diversity and developing capacities of community institutions for their management. The research involved six communities in Ségou and Sikasso regions. Multiple varieties of fonio (10–12) and Bambara groundnut (8–12) were established in diversity fields in each site over 2 years where farmers engaged in experiential learning over the crop cycle. Significant adoption of fonio and Bambara groundnut was detected in several study sites. The precise drivers of adoption cannot be definitively determined but likely include increased seed access and awareness gained through the diversity field fora, seed fairs and community seed banks. No significant yield advantage was detected for any of the varieties in the diversity fields, which showed variable performance by site and year. The number of varieties registered and managed by community seed banks in each site increased from 1–5 varieties of each crop to 11–12 varieties following the interventions. The number of Bambara groundnut varieties cultivated in farmers' fields also increased, while there was evidence of a slight decline in fonio diversity in some communities. The results of this study can inform efforts to strengthen seed systems and cultivation of neglected and underutilized species in Africa.

The goal of most rice improvement programs is the enhancement of farmers’ yield using less land and limited water. This study evaluated 77 upland rice genotypes under optimal upland growing conditions in the field and ranked the genotypes using base indices. Subsequently, eighteen cultivars selected from the field trial were screened under drought in rainout-shelter conditions. The traits evaluated for index selection were yield, days to flowering, plant height, number of panicles and filled grains. Under field conditions, based on the sum of economic weight assigned to five traits used to compute the selection index, IR 68704-145-1-1-B and IR 63380-16 were the best genotypes. In the rainout-shelter experiment, Ofada 2 (508 gm−2) had the highest grain yield under non-stress conditions while ITA 117 (152.38 gm−2) had the highest grain yield under drought stress. The base index was efficient for selecting superior genotypes with the best combination for all the traits considered. Susceptibility to drought stress of the landraces leads to poor grain yield.

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.

The north-western Himalaya is one of the rich repositories of wheat genetic resources because of the preponderance of locally developed traditional crop varieties owing to high agro-climatic heterogeneity and local socio-cultural diversity. In the present study, 100 wheat landraces of this diversity rich region were evaluated for variability in physical parameters of seed to understand the basis of resistance against rice weevil, Sitophilus oryzae. The evaluation was based on the parameter of growth index (GI) of S. oryzae in different landraces. GI was correlated with different quantitative physical seed parameters, viz. hardness, length, width, length × width, test weight and qualitative parameter seed colour were studied to work out if these were related to resistance/susceptibility. Based on the parameter of GI, the six landraces viz. IC266831, IC266872, IC393109, IC392578, IC444217 and IC589276 were identified as resistant. Correlation coefficients between GI of S. oryzae and physical parameters of wheat landraces indicated that GI had significant positive relation with length × width (r = +0.573) and test weight (r = +0.549) indicated that small seeds confer resistance to S. oryzae. Also significant negative relation (r = −0.457) with GI of S. oryzae and seed hardness, indicated that hard seeds were relatively more resistant to S. oryzae.

Landraces are an important resource for crop breeding, due to their resilience and content of quality traits. However, genetic and phenotypic variability needs to be carefully characterized for proper direct and indirect use. In the present study, a multidisciplinary approach was carried out to assess the Italian sweet pepper landrace ‘Friariello’. A total of 18 traditional accessions were compared with five hybrids and two ecotypes with similar fruit typology. Genetic and morpho-agronomic characterization allowed us to distinguish five different group types of ‘Friariello’. Accessions showing two/three lobes at the blossom end of the fruit were found to be the most productive, whereas the genotypes showing one/two lobes at the blossom end were the most homogeneous. A total of 167 volatile organic compounds (VOCs) were identified in the collection analysed. Moreover, of the 37 targeted VOCs, 29 showed significant differences in content among the pepper genotypes studied. Of such VOCs related to main flavours described for pepper in the literature, ten were found to be the major determinants of variability among the derived ‘Friariello’ groups. A slightly negative, albeit not significant, correlation was observed between ascorbic acid (AsA) content and agronomic traits, suggesting a better quality for less productive accessions, but also the possibility to improve yield without significantly reducing the AsA levels. The approach used allowed us to define how the different typologies can be used for different breeding purposes, integrating the peculiar properties in order to establish a desirable landrace ideotype. Furthermore, valuable sources for improving quality traits in pepper breeding were identified.

In Uruguay, onion (Allium cepa L.) germplasm is mainly derived from the genetic material introduced by several waves of European immigrants and subsequently multiplied by household farmers, resulting in a wealth of locally adapted populations. This study examined the genetic diversity in a collection of 27 local onion populations and two cultivars derived from them. A total of 843 onion plants were fingerprinted, and 83 inter-simple sequence repeat polymorphic bands were generated. Analysis of molecular variance showed high diversity within the populations (66% of the total variation). Some short-day populations from different geographical origins were grouped together by the unweighted pair-group method using arithmetic averages, principal coordinate analysis and cluster analysis, while the more extensively sampled long- and intermediate-day populations showed a widespread distribution, with no significant subgrouping among them. This weakly structured gene pool is probably the consequence of seed and bulb exchange between farmers and natural inter-pollination. Nevertheless, a Bayesian analysis allowed the distinction of four genetic backgrounds of alleles in the whole collection, and populations were predominately assigned to each genetic background. In addition, mitochondrial variants determining normal (N) pollen fertility or the sterile S or T types were analysed for the same set of plants using specific primers. Most accessions showed a proportion of male-sterile individuals. Cytoplasm type T was the most represented (26 out of 29 accessions), and cytoplasm type S was found in a low proportion of individuals in seven populations. Uruguayan onion germplasm maintains a low degree of genetic differentiation despite the small cultivated area and intense seed exchange, probably due in part to different market purposes based on the growing cycle.

The allelic variations at glutenin loci could significantly affect the bread baking quality, and specific glutenin alleles might be closely associated with greater gluten strength, which, in turn, is related to superior bread baking quality. In this study, allelic variations at Glu-1, Glu-A3 and Glu-B3 loci were evaluated in 222 Korean wheat landraces using gene-specific polymerase chain reaction (PCR) markers. Ten alleles were identified at Glu-1 loci. Glu-A1c, Glu-B1b, and Glu-D1a or Glu-D1f alleles were predominantly found at the respective loci and their frequencies were 86.5, 87.8 and 96.9 %, respectively. Seven Korean wheat landraces carried the Glu-D1d allele, and only one Korean wheat landrace (IT173162) achieved 10 points for the Glu-1 score. Fifteen alleles were identified at Glu-A3 and Glu-B3 loci; Glu-A3c and Glu-B3d or Glu-B3i alleles were commonly found at the respective loci and their frequencies were 77.0, 33.3 and 37.8 %, respectively. Glu-B3 alleles exhibited the highest genetic diversity than other alleles, while Glu-B1 and Glu-A1 alleles exhibited the lowest genetic diversity than other alleles. Twenty Korean wheat landraces had the Glu-A3d and Glu-B3b, Glu-B3d, Glu-B3f, Glu-B3g or Glu-B3i alleles, which were correlated with superior bread baking quality. Among these wheat lines, two (IT59787 and IT236544) carried the Glu-D1d allele.