In this study, a forward-genetics analysis was performed on a portion of TILLMore, a chemically mutagenized population of barley cv. ‘Morex’ (http://www.distagenomics.unibo.it/TILLMore/), to identify root morphology alterations by comparison with ‘Morex’ wild-type. For this purpose, a simple paper-roll approach was performed to identify phenotypic variants at the seedling stage. The analysis of c. 1000 M4 families allowed us to identify c. 70 lines with altered root morphology. A more accurate phenotypic characterization of a portion of the mutant lines has been performed using stereomicroscopy and a scanning electron microscopy approach.

Yellow endosperm maize can be used to reduce vitamin A deficiency among many pre-school children and women of reproductive age in sub-Saharan Africa. Assessment of the genetic diversity of tropical yellow endosperm maize inbred lines will have genetic gains in breeding design to develop lines with an enhanced level of provitamin A. We screened 122 tropical yellow endosperm maize inbred lines with 62 simple sequence repeat (SSR) markers and 51 SSR loci were polymorphic. We detected 190 alleles with an average of 3.72 alleles per locus, and polymorphic information content values among the inbred lines varied from 0.12 to 0.74 with an average of 0.43. Genetic distance (GD) values among all the pairs of the 122 inbred lines varied from 0.02 to 0.61 with an average of 0.41 for the SSR markers. The inbred lines exhibited a substantial level of genetic diversity. Genetic diversity was also evaluated using carotenoid data. The Euclidean GDs varied from 1.00 to 9.97 with an average of 3.81 for the carotenoid data. Cluster and principal coordinate analyses revealed clear separation of maize inbred lines into SSR-based groupings and carotenoid-based groupings. Cluster based on SSR markers were predominantly consistent with known pedigree data of the inbred lines. The correlation using Mantel's test between carotenoid-based GD estimates and SSR marker-based GD estimates gave a low r value ( − 0.06). The grouping of lines will facilitate the selection of parental lines for making crosses to develop new lines with enhanced provitamin A content.

Triticum monococcum L. and T. boeoticum L., diploid wild relatives of bread wheat (T. aestivum L.), possess resistance to leaf rust (also known as brown rust) caused by Puccinia triticina Eriks. Haustorium formation-based resistance mechanisms (i.e. pre-haustorial and post-haustorial resistance) to leaf rust have been studied and reported in various T. monococcum accessions. In the present study, the mechanism of leaf rust resistance in T. monococcum and T. boeoticum accessions was studied using confocal laser scanning microscopy. Components of resistance studied at a histological level against leaf rust pathotypes, a Mexican pathotype (TCB/TD) and a Swiss pathotype (97512-19), indicated different types of resistance mechanism operative in the two accessions. The resistance in T. monococcum ranged from pre-haustorial resistance against 97512-19 to post-haustorial resistance against TCB/TD. The response in T. boeoticum was post-haustorial with necrosis against the two pathotypes. Pre-haustorial resistance observed in T. monococcum could serve as a potential source of durable rust resistance in wheat breeding.

The genus Malacomeles (Decne.) G. N. Jones (Rosaceae subtribe Pyrinae) represents several fruit shrubs, which is mainly distributed in North and Central America, from southern USA to Honduras and Guatemala, although the main distribution of this genus is in Mexico. Five species of the genus Malacomeles have been reported to exist in Mexico. Malacomeles is widely distributed in several mountainous ranges in Mexico, although it is unknown where most of the diversity of the Malacomeles genus is located in the country. The aim of this biogeographic study was to determine the areas of highest diversity of the genus Malacomeles in Mexico based on species richness and diversity indices in order to identify the best regions of Mexico to collect germplasm. The results indicated that most of the diversity of the genus Malacomeles is concentrated in northeast Mexico, mainly in the biogeographic province of Sierra Madre Oriental. In this province, the highest values on three biodiversity indices were found. Thus, this area can be considered as the priority area to collect the germplasm of Malacomeles. M. denticulata is the predominant and the most interesting species in Mexico from the viewpoint of collecting plant genetic resources; this species is mainly distributed in the provinces of Trans-Mexican Volcanic Axis, Mexican Plateau and Sierra Madre del Sur, where secondary priority areas to collect germplasm are located.

For more than four decades after the introduction of cv. Italia (Vitis vinifera L.) in Brazil, several somatic mutations in the genome of cv. Italia and its somatic mutants gave rise to phenotypes which generated at least five new cultivars of fine table grapes. Since no molecular marker proved to be effective in discriminating cv. Italia (V. vinifera L.) and its coloured mutants (Rubi, Benitaka, Brasil, Black Star), primers for the long terminal repeat (LTR) sequences were developed to analyse Inter Retrotransposon Amplified Polymorphism (IRAP) and Retrotransposon-Microsatellite Amplified Polymorphism (REMAP), and investigate how the coloured cultivars derived from clonal propagations of somatic mutations are genetically structured. Primers for LTR sequences of IRAP and REMAP markers were edited from grape sequence databases available at a GenBank. Twenty-four primers, denominated DKS001–DKS024, were edited. Three hundred and forty-nine DNA segments were amplified by individual DKS primers and DKS/ISSR (Inter Simple Sequence Repeats) primer combinations, at an average of 13.96 amplicons per primer pair. High genetic divergence between the five cultivars was inferred from polymorphism in retrotransposons IRAP and REMAP. The analysis of polymorphism of IRAP and REMAP retrotransposons was crucial to show that clonal propagation of somatic mutations may lead towards the formation of genetically divergent cultivars by the formation of genetically structured vineyards and show the mixture of genomes within each cultivar.

To preliminarily evaluate the genetic diversity of the Iranian diploid Triticum L. gene pool, in this study, a total of 176 individuals belonging to T. monococcum L. ssp. aegilopoides (Link) Thell. and T. urartu Thum. ex Gandil. were pre-screened using single-strand conformation polymorphism (SSCP) analysis of the Acc-1 and Pgk-1 loci. A selected set of 76 DNA samples corresponding to the observed SSCP variants were sequenced for both loci and evaluated for nucleotide diversity associated with the taxonomic groups and geographical regions. We found three haplotypes, including one that was new for Iran, at each locus. Population structure and analysis of molecular variation results proved that the collection evaluated could be genetically divided into two distinct groups, which to a great extent was in accordance with the taxonomic classification. A genetic leakage from T. monococcum ssp. aegilopoides into T. urartu was observed during structure analysis, which was inferred on the basis of occasional outcrossing, despite their inbreeding nature. The results revealed that there was no variation within the populations belonging to T. urartu, while a meaningful variation was found between the geographical regions for T. monococcum ssp. aegilopoides. The median-joining networks revealed a conflict between morphology and haplotype variation, which was interpreted on the basis of introgressive hybridization, recombination signature and rapid speciation. In conclusion, we suggest that SSCP analysis is a useful tool in regions where thorough sequencing of an enormous number of DNA samples is time consuming and not affordable.

Seeds of wild and cultivated species of Luffa were studied to determine the variability in morphological (seed size, colour, seed-coat surface and 100-seed weight) and biochemical (oil and protein) characteristics. A total of 80 accessions of three cultivated species (71 accessions) and three wild species (9 accessions) of Luffa under the present investigation from diverse regions (12 states of five regions) of India showed variations in seed size, colour, seed-coat surface, 100-seed weight, and seed protein and oil contents both within the accessions of the same species and between different species. Significant variability in seed morphological traits was observed. Both seed oil and soluble seed protein contents were highest in some accessions of the cultivated species (25–27% oil and 8–10% protein, respectively, on a fresh seed weight basis). Using the 2D scatter plot diagram derived from the principal components analysis, the morphological and biochemical traits of the 80 Luffa accessions classified the wild species into one cluster (cluster I) and the cultivated species into a second major cluster (cluster II). The present investigation on the correlation between seed morphology and biochemical traits in the cultivated and wild species of Luffa can help in identifying the genotypes of Luffa species with valuable traits for further exploring the potential of this valuable crop as a source of edible oil, food and fodder in edible seed types or as a source of industrial oil/biodiesel in non-edible seed types. The protein-rich seed could be further explored to be utilized in the fortification of food products for value addition.

Bamboo shoots and leaves are valuable food sources for both humans and livestock. The USDA-ARS NPGS (National Plant Germplasm System) collections hold 93 bamboo species in 20 genera. Total leaf protein, amino acid composition and elemental content for these important genetic resources had never been quantified. Lack of nutrition information hinders germplasm utilization. The above-mentioned nutritional traits were evaluated from these 93 species in this study. Leaf protein content among bamboo species ranged from 8.12 to 16.33% with an average of 12.84%. This average was higher than 9.0% observed for switchgrass leaves, but considerably lower than 32.48% in cassava leaves. For 18 quantified amino acids, there was more than a twofold variation among the samples evaluated. For 12 quantified mineral elements, there was significant variability from the low end (4.2-fold, 2.27–9.52 mg/g calcium; 4.4-fold, 56.17–246.43 µg/g sodium) to the high end (61.5-fold, 17.67–1087.0 µg/g manganese; 40.8-fold, 42.0–1713.5 µg/g aluminium). Due to their variability in leaf nutritive value, bamboo species should be carefully chosen when they are used as a feedstock. The results from this study will be useful for the bamboo industry, producers and consumers.

In this study, agro-morphological and yield-related traits associated with drought tolerance in 80 barley genotypes belonging to 15 wild species together with the cultivated one, and their potential to improve adaptation to different levels of drought stress conditions (moisture environments) were studied. There was significant genetic variation among the genotypes and species for all of the measured traits, as well as differential responses of genotypes across environments. The results indicated high variation for grain yield (GY) under drought stress among the genotypes, and that some of the wild genotypes had consistently superior specific adaptation to the water stress conditions. The genotypes belong to wild barley species, especially Hordeum murinum and Hordeum marinum had lower GY but relatively higher yield stability under different environments. Traits such as number of seed per plant and hundred kernel weight were positively correlated with GY in all of the environments. High negative correlation between GY and days to ripening was observed only under intense drought environment, showing drought escape as a strategy of wild plants under highly stressed conditions. Grouping of the genotypes by principal component analysis completely separated cultivated barley and its progenitor (Hordeum vulgare ssp. spontaneum) from other wild genotypes; however, the other wild species were slightly separated from each other. In addition, the Iranian and foreign genotypes did not completely separate from each other. The identified wild barley genotypes with favourable characters and high drought tolerance could be used in genetic studies and barley improvement programmes especially for drought stress.

In order to gain an understanding of the genetic basis of traits of interest to breeders, the pea varieties Brutus, Enigma and Kahuna were selected, based on measures of their phenotypic and genotypic differences, for the construction of recombinant inbred populations. Reciprocal crosses were carried out for each of the three pairs, and over 200 F2 seeds from each cross advanced to F13. Bulked F7 seeds were used to generate F8–F11 bulks, which were grown in triplicated plots within randomized field trials and used to collect phenotypic data, including seed weight and yield traits, over a number of growing seasons. Genetic maps were constructed from the F6 generation to support the analysis of qualitative and quantitative traits and have led to the identification of four major genetic loci involved in seed weight determination and at least one major locus responsible for variation in yield. Three of the seed weight loci, at least one of which has not been described previously, were associated with the marrowfat seed phenotype. For some of the loci identified, candidate genes have been identified. The F13 single seed descent lines are available as a germplasm resource for the legume and pulse crop communities.

Leaf pubescence is widespread among higher plants. In bread wheat, a relationship was found between this trait and the efficiency of photosynthetic processes and productivity. In this work, we established the chromosomal localization of the gene for leaf pubescence introgressed from Triticum timopheevii into a bread wheat line 821 and studied its expression in the genetic background of two wheat cultivars differing in genetic control and phenotypic expression of pubescence. To obtain quantitative characteristics of pubescence in cultivars and hybrid populations, the LHDetect2 program was used, which makes it possible to estimate the length and number of trichomes on a leaf fold. A genetic analysis showed the dominant inheritance of the gene. Monosomic analysis F2 was used to establish chromosome localization and investigate the expression of the gene in cultivars Saratovskaya S29 (S29) and Diamant 2 (Dm2). As a result, the gene Hltt, introgressed from T. timopheevii, was identified and localized in the distal region of the long arm of 5A chromosome for the first time. In both F2 populations, the gene reduced the density of trichomes and formed long trichomes, uncharacteristic for the two recipient cultivars S29 and Dm2. A larger number of long trichomes was formed in the genetic background of S29, which carry the bread wheat gene Hl1 and Hl3 for leaf pubescence, than in Dm2. Development of substitution and isogenic lines with the fragment of introgression carrying the gene Hltt will allow determining function and assessing the adaptive significance of the gene more precisely.

The development of crop varieties with enhanced economic value requires considerable resources, time and intellectual input. The individual/agencies/institutions other than the originator/developers can easily multiply and commercialize pure-line varieties which are the only cultivar option in predominantly self-pollinated crops like dolichos bean and derive economic benefits from them. Seeking legal rights on crop varieties is the best and the only way to protect them from unlawful claim of their origin/development and deriving economic benefits from them. Seeking legal protection from unauthorized commercialization of crop varieties under Indian PPV & FR Act requires establishment of their distinctness (D), uniformity (U) and stability (S). DUS of crop varieties are established predominantly using morphological descriptors. Five genotypes which include two released varieties (HA 3 and HA 4) (referred to as reference varieties) and one advanced breeding line, HA 11–3 and two elite germplasm accessions, Kadalavare and GL 66 (referred to as candidate varieties) were characterized for 25 morphological descriptors to establish their DUS. All the candidate varieties differed from reference varieties for at least one characterization descriptors, indicating their distinctness. The absence of off-types indicated the uniformity of reference and candidate varieties and hence was deemed stable. Thus, the study demonstrated the utility of morphological descriptors for establishing DUS dolichos bean genotypes.

Genetic resources form the basis of the new era of global food security. The food crises in many developing countries, reflected by food riots correlated with food prices, have been termed the Silent Tsunami. Plant genetic resources are clearly essential to food security for the future. Fortunately, genetic resources are generally considered a public good and shared internationally. Wild relatives of crop species and their derivatives represent the reservoir of genetic diversity that will help to meet the food demands of nine billion people by 2050. New technologies from genomics bolster conventional plant breeding for enhancing traits to meet these food demands. Genetic diversity is the lifeblood of traditional and modern plant breeding. The dramatic increase in the number of biotech crops reveals the value of new genetic resources. Genetic resources will provide a gateway to a new era of global food security. Although 7.4 million plant accessions are stored in 1750 germplasm banks around the world, only a small portion of the accessions has been used so far to produce commercial varieties. Our challenge is to find better ways to make more efficient use of gene bank materials for meeting food demands in the future.

A blueberry (Vaccinium sp.) germplasm collection was screened for allelic variation in TERMINAL FLOWER 1 (TFL1) that could be used in breeding flowering or architecture traits. TFL1 has been found to repress the transition from vegetative to reproductive growth in diverse plant species, with mutations leading to altered flowering and form. The VcTFL1 gene sequence was determined from the draft genome sequence of diploid V. corymbosum line W8520. VcTFL1 is a member of a PEBP gene family and it could be distinguished from its family members by sequence comparison with PEBP family genes from other plants. High-resolution DNA melting analysis of 160 Vaccinium accessions detected VcTFL1 exons that differed in sequence from the W8520 control. DNA sequence analysis confirmed the presence of single nucleotide polymorphisms (SNPs) and identified haplotypes of tetraploid accessions. A total of 18 SNP sites were detected in VcTFL1 coding sequences of the Vaccinium germplasm screened. A SNP causing an alanine-to-valine change in exon 4 (A159V) was determined by multiple bioinformatic tools to be deleterious to VcTFL1 function. A diploid V. corymbosum accession heterozygous for the VcTFL1 mutation was identified as a candidate for breeding novel traits for blueberry.

Monitoring and protecting germplasm in genebanks using in situ collections while preserving its original genetic integrity is a priority of germplasm curation. Many germplasm accessions need to be regenerated due to their demand and/or seed condition. The regeneration of wild Helianthus (sunflower) species poses several challenges due to the diversity of 53 wild species. Fatty acid composition of sunflower oil is an important quality factor for the crop. Since oil quality is environmentally influenced, and evaluation of this trait is usually performed on oil from achenes from the original accessions of wild sunflower species, we conducted a study on 72 accessions of eight annual and four perennial taxa of wild sunflower species to compare the oil quality of the original accessions and those regenerated for genebank maintenance. The results showed that the fatty acid composition profiles of achenes from the original and regenerated accessions are not the same. It seems that selection for specific fatty acids in several species will require the analysis of both populations to identify germplasm accessions for use in breeding programmes. It should be borne in mind that accessions of wild species are open-pollinated segregating populations, so one would expect some variability in each succeeding generation. While there may be differences between the original and regenerated accessions, the interrelationships of fatty acids are generally similar in wild and cultivated sunflower species, so there should be no detrimental effects on oil quality when using the wild species for other traits. As more regenerated accessions become available, a more precise relationship between the original and regenerated accessions should emerge.

The large variation in multifactorial and seemingly non-adaptive kernel colour traits displayed by Native American maize landraces is an evidence of recurring selection for perceptual distinctiveness. Native American farmers selected for colour traits that allowed them to distinguish between and maintain large diversity within maize landraces for traditional uses. Multivariate statistical procedures were employed to quantify the variation and interrelationships between physical traits, C:N ratio, protein content, micro- and macronutrient concentrations with kernel colour traits measured on random kernel samples of Northern flint maize landraces grown for 2 years in a common-garden experiment. The colour traits (L*, a* and b* indicating dark–light, red–green and yellow–blue colour continuum, respectively) were digitally quantified on 590 random kernels from each of 28 accessions in 11 landraces. Accessions within landraces exhibited the largest variation for all colour traits. The variation in the L*a*b*, L*a* and L*b* combinations explained significant variances in 37, 14 and 37% of 120 landrace–trait combinations, respectively; the remaining 12% were explained by L*, a* or b*. On average, 37.5% of the variation in protein content (range 19.2–64.5%) and 36.6% of the variation in the C:N ratio (range 15.7–65.0%) were explained by the combinations of colour traits in different landraces. Slightly larger average variations in K (43.7%), S (43.0%), Fe (42.2%) and P (40.8%) were accounted for by colour traits. A hierarchical and joint clustering procedure of landraces and traits was developed to facilitate the identification of large variation and the selection of single or multiple traits based on kernel colour traits with reasonable certainty.

Nineteen kenaf genotypes from Cuba, Taiwan, the USA, El Salvador, Guatemala, Russia, Spain and Indonesia, and three wild types collected in South Africa were analysed for genetic diversity using AFLP analysis. All could be uniquely distinguished from one another, but only a low level of genetic diversity was present. The most distinct accession, Guatemala 4, was 85% similar to all other accessions. The accessions clustered more or less according to known pedigree and/or origin. Two of the three wild types (Hibiscus cannabinus c and H. cannabinus a) clustered separately from the commercial and Russian accessions. One of the wild types, H. cannabinus b clustered with some of the commercial accessions. Commercial accessions in the first subgroup all originated from central and North America, and surrounding islands (Cuba and El Salvador). The Russian accessions are all grouped together. The second subgroup was the only group that contained accessions from different geographical origins.

Andean blackberry (Rubus glaucus Benth.) is an emerging fruit crop with significant commercial potential. Despite its growing popularity, basic research about its genetic resources and breeding remains insufficient. The aim of this study was to assess the genetic diversity of Andean blackberry cultivars and related berries species from the main production areas in Ecuador. We analysed a total of 106 samples and performed DNA screening with different molecular markers: random-amplified polymorphic DNAs (RAPDs), inter-simple sequence repeats (ISSRs) and a set of representative samples with amplified fragment length polymorphisms (AFLPs). The tested RAPD primers did not reveal any differentiation among accessions identified as R. glaucus, however one ISSR primer was useful to find polymorphisms allowing the selection of 29 accessions for the analysis with AFLP markers. AFLP-M13 technology was used for screen genetic variations among these accessions and eight wild Rubus accessions. We scored 203 bands using five primer combinations; out of these 152 were informative in R. glaucus. AFLP markers clearly distinguish R. glaucus from the screened wild Rubus species, also an unexpected genetic structure was revealed among R. glaucus cultivars. This genetic differentiation and detection of admixed genotypes suggest a possible introgression of wild Rubus species in R. glaucus. Our findings are relevant for blackberry genetic breeding and use of these genetic resources.

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.

Natural products from plants are still important sources for the development of drugs, despite their recent neglect in pharmaceutical discovery programmes. The rapidly dwindling number of species endangers the availability of these natural compounds, which are characterized by the immense chemical and functional diversity ultimately responsible for their pharmaceutical activity. Although many steps in the drug discovery process have been continuously modified during recent years, a common dilemma is still unresolved, i.e. the supply crisis for hits discovered in rare wild plants due to their inaccessibility or lack of reproducibility. New technology, combining tissue culture, functional genomics and metabolomics, shows promise to overcome these problems and even to supply a greater chemical diversity of compounds.