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Proteases, including serine proteases, are involved in the entire life cycle of plants. Proteases are controlled by protease inhibitors (PI) to limit any uncontrolled or harmful protease activity. The role of PIs in biotic and abiotic stress tolerance is well documented, however their role in various other plant processes has not been fully elucidated. Seed development is one such area that lack detailed work on the function of PIs despite the fact that this is a key process in the life cycle of the plant. Serine protease inhibitors (SPI) such as the Bowman-Birk inhibitors and Kunitz-type inhibitors, are abundant in legume seeds and act as antinutrients in humans and animals. Their role in seed development is not fully understood and present an interesting research target. Whether lowering the levels and activity of PIs, in order to lower the anti-nutrient levels in seed will affect the development of viable seed, remains an important question. Studies on the function of SPI in seed development are therefore required. In this Perspective paper, we provide an overview on the current knowledge of seed storage proteins, their degradation as well as on the serine protease-SPI system in seeds and what is known about the consequences when this system is modified. We discuss areas that require investigation. This includes the identification of seed specific SPIs; screening of germplasms, to identify plants with low seed inhibitor content, establishing serine protease-SPI ratios and lastly a focus on molecular techniques that can be used to modify seed SPI activity. [ABSTRACT FROM AUTHOR]

The Asparagus genus includes approximately 240 species, the most important of which is garden asparagus (Asparagus officinalis L.), as this is a vegetable crop cultivated worldwide for its edible spear. Along with garden asparagus, other species are also cultivated (e.g., Asparagus maritimus L.) or have been proposed as untapped sources of variability in breeding programs (e.g., Asparagus acutifolius L.). In the present work, we applied reduced-representation sequencing to examine a panel of 378 diverse asparagus genotypes, including commercial hybrids, interspecific lines, wild relatives of garden asparagus, and doubled haploids currently used in breeding programs, which enabled the identification of more than 200K single-nucleotide polymorphisms (SNPs). These SNPs were used to assess the extent of linkage disequilibrium in the diploid gene pool of asparagus and combined with preliminary phenotypic information to conduct genome-wide association studies for sex and traits tied to spear quality and production. Moreover, using the same phenotypic and genotypic information, we fitted and cross-validated genome-enabled prediction models for the same set of traits. Overall, our analyses demonstrated that, unlike the diversity detected in wild species related to garden asparagus and in interspecific crosses, cultivated and wild genotypes of A. officinalis L. show a narrow genetic basis, which is a contributing factor hampering the genetic improvement of this crop. Estimating the extent of linkage disequilibrium and providing the first example of genome-wide association study and genome-enabled prediction in this species, we concluded that the asparagus panel examined in the present study can lay the foundation for determination of the genetic bases of agronomically important traits and for the implementation of predictive breeding tools to sustain breeding. [ABSTRACT FROM AUTHOR]

Common bean seeds are an excellent source of protein as well as of carbohydrates, minerals, vitamins, and bioactive compounds reducing, when in the diet, the risks of diseases. The presence of bioactive compounds with antinutritional properties (e.g., phytic acid, lectins, raffinosaccharides, protease inhibitors) limits, however, the bean's nutritional value and its wider use in food preparations. In the last decades, concerted efforts have been, therefore, made to develop new common bean genotypes with reduced antinutritional compounds by exploiting the natural genetic variability of common bean and also applying induced mutagenesis. However, possible negative, or positive, pleiotropic effects due to these modifications, in terms of plant performance in response to stresses or in the resulting technological properties of the developed mutant genotypes, have yet not been thoroughly investigated. The purpose of the perspective paper is to first highlight the current advances, which have been already made in mutant bean characterization. A view will be further provided on future research directions to specifically explore further advantages and disadvantages of these bean mutants, their potential use in innovative foods and representing a valuable genetic reservoir of combinations to assess the true functional role of specific seed bioactive components directly in the food matrix. [ABSTRACT FROM AUTHOR]

Global climate change, causing large parts of the world to become drier with longer drought periods, severely affects production of common beans (Phaseolus vulgaris L.). The bean is worldwide the most produced and consumed food grain legume in the human diet. In common beans, adapted to moderate climates, exposure to drought/heat stress not only results in significant reduction of bean yield but also the nutritional value. This review explores the contribution of common beans to food and nutrient security as well as health. Also discussed is the existing knowledge of the impact of drought/heat stress, associated with a changing climate, specifically on iron (Fe) and phytic acid (PA) that are both among the most important mineral and anti‐nutritional compounds found in common beans. Further discussed is how the application of modern "omics" tools contributes in common beans to higher drought/heat tolerance as well as to higher Fe and reduced PA content. Finally, possible future actions are discussed to develop new common bean varieties with both improved drought/heat tolerance and higher mineral (Fe) content. [ABSTRACT FROM AUTHOR]

Abstract: Food safety and quality are nowadays a major concern. Any case of food alteration, especially when reported by the media, has a great impact on public opinion. There is an increasing demand for the improvement of quality controls, hence addressing scientific research towards the development of reliable molecular tools for food analysis. DNA barcoding is a widely used molecular-based system, which can identify biological specimens, and is used for the identification of both raw materials and processed food. In this review the results of several researches are critically analyzed, in order to exploit the effectiveness of DNA barcoding in food traceability, and to delineate some best practices in the application of DNA barcoding throughout the industrial pipeline. The use of DNA barcoding for food safety and in the identification of commercial fraud is also discussed. [Copyright &y& Elsevier]

Highlights • 469 molecular profiles of apple accessions collected in Friuli Venezia Giulia, north-eastern Italy, and maintained in 3 different locations were analysed at 15 SSR markers. • 234 not redundant accessions were identified; of these 102 were synonyms. • Of the remaining 132 unique accessions, 54 were triploid (40.9%), a percentage never reported so high in the literature. • The genetic diversity was very high and comparable with that reported for larger collections analysed in the recent literature. • Microsatellite DNA (or SSR) remains an interesting marker; however the di-nucleotide core repeats, popular in apple genotyping, have some drawbacks that might make hard the attempts to align data sets produced by different laboratories. Abstract This paper reports the genetic diversity of apple germplasm collected in the Friuli Venezia Giulia region (north-eastern Italy). The collection, maintained in three different locations, was represented by local cultivars which probably originated as chance seedlings together with cultivars introduced from neighbouring countries, the name and origin of most of which has been lost over time. A preliminary procedure described in the paper started with 469 molecular profiles analysed using 15 Simple Sequence Repeat (SSR) markers and allowed identification of the 'true-to-type' genotypes among those maintained in multiple locations. The set of the remaining 234 accessions was further reduced to 132 unique profiles by removing 102 synonyms, that is accessions with different name and the same molecular profile. Flow cytometry identified as many as 54 triploids (40.9%), whose status was confirmed by field observations on leaf size and the occurrence of triallelic profiles at several SSR markers. The remaining 78 diploid accessions were analysed for their genetic diversity, that is the number of alleles, observed and expected heterozygosity, polymorphism information content (PIC), the frequency of null alleles and the probability of identity for unrelated and full-sib genotypes. The paper provides a critical evaluation of the SSR markers adopted for the study, discusses the genetic diversity observed in the apple germplasm collection examined as well as its high frequency of triploids compared with other apple collections described in the literature. [ABSTRACT FROM AUTHOR]

Phytic acid (InsP 6 ) is the main storage form of phosphate in seeds. In the plant it plays an important role in response to environmental stress and hormonal changes. InsP 6 is a strong chelator of cations, reducing the bioavailability of essential minerals in the diet. Only a common bean low phytic acid ( lpa1 ) mutant, affected in the PvMRP1 gene, coding for a putative tonoplastic phytic acid transporter, was described so far. This mutant is devoid of negative pleiotropic effects normally characterising lpa mutants. With the aim of isolating new common bean lpa mutants, an ethyl methane sulfonate mutagenized population was screened, resulting in the identification of an additional lpa1 allele. Other putative lpa lines were also isolated. The PvMRP2 gene is probably able to complement the phenotype of mutants affected in the PvMRP1 gene in tissues other than the seed. Only the PvMRP1 gene is expressed at appreciable levels in cotyledons. Arabidopsis thaliana and Medicago truncatula transgenic plants harbouring 1.5 kb portions of the intergenic 5′ sequences of both PvMRP genes, fused upstream of the GUS reporter, were generated. GUS activity in different organs suggests a refined, species-specific mechanisms of regulation of gene expression for these two PvMRP genes. [ABSTRACT FROM AUTHOR]

• Genetic reduction of phytic acid results in hard-to-cook phenotype in common bean seeds. • Cooking increases stability of PHA-L lectin in low phytic acid1 mutant. • Addition of a cation chelator during cooking reverses stability of PHA-L lectin. • Calcium redistribution occurs in black low phytic acid1 seeds. • Low phytic acid1 seeds contain fewer phytate globoids than wild type. Seed phytic acid reduces mineral bioavailability by chelating minerals. Consumption of common bean seeds with the low phytic acid 1 (lpa1) mutation improved iron status in human trials but caused adverse gastrointestinal effects, presumably due to increased stability of lectin phytohemagglutinin L (PHA-L) compared to the wild type (wt). A hard-to-cook (HTC) defect observed in lpa1 seeds intensified this problem. We quantified the HTC phenotype of lpa1 common beans with three genetic backgrounds. The HTC phenotype in the lpa1 black bean line correlated with the redistribution of calcium particularly in the cell walls, providing support for the "phytase-phytate-pectin" theory of the HTC mechanism. Furthermore, the excess of free cations in the lpa1 mutation in combination with different PHA alleles affected the stability of PHA-L lectin. [ABSTRACT FROM AUTHOR]