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The results of the exploration missions for the gathering of legume germplasm in Monti Dauni district (southern Italy) are presented. The 52% of collected samples were common beans (Phaseolus vulgaris L.), mainly white seeded types. Information acquired in the frame of different research areas, such as passport data, GIS data, historical documents on crop cultivation in the study district, were integrated data with orthophotos and satellite images. This interdisciplinary approach allowed to obtain a multidimensional data set for the collected local varieties. A similar holistic approach permits a better knowledge of the link between the local varieties and the traditional area of cultivation, as well as the contextualization of their cultivation in both space and time. The merger of different information overcomes the limits derived from the use of a single methodology and might support local communities and policy-makers in the planning of effective actions aimed to safeguard the autochthonous germplasm.

Genotyping by sequencing (GBS) was used to analyze relationships among cowpea and asparagus bean landraces from southern Italy and to assess the utility of this technology to study taxonomy in a wider panel, including V. unguiculata cultigroups, subspecies, and other Vigna species. The analysis of SNPs derived from GBS highlighted that, among the cowpea landraces, the African samples were separated from the other material, while, for the Italian landraces, a certain clustering depending on seed color/pattern was observed in the dendrogram. When examining the V. unguiculata species complex, a clear separation between the two groups of wild subspecies, i.e., the allogamous wild perennials and the perennial out/inbreds, could be observed, the former representing the more ancestral wild progenitors of V. unguiculata. The species V. vexillata appeared more closely related to V. unguiculata than to the other Vigna species analyzed.

Cowpea (Vigna unguiculata (L.) Walp.) is a major tropical pulse in a number of countries and especially in sub-Saharan Africa where this species was domesticated. Although as niche product, a remarkable number of cowpea landraces are cultivated in the Mediterranean basin, primarily for human consumption of the grains and fresh pods. In this study, within the frame of a regional project devoted to the safeguard and management of local horticultural genetic resources, some germplasm explorations were carried out in Apulia region (southern Italy) to collect, among other crops, cowpea landraces still present in the area and promote on-farm conservation of this traditional material. A second objective was to investigate the efficiency of SSR markers in detecting genetic polymorphism in cowpea landraces from a restricted geographical area. In total, 13 samples of V. unguiculata were gathered, 12 of cultivar group unguiculata and 1 of cultivar group sesquipedalis. Genetic diversity and phylogenetic relationships among 13 Apulian accessions, 9 samples from various provenances and 1 var. spontanea accession were evaluated using SSR molecular markers. A set of 19 SSR primer pairs successfully identified closely related accessions and were able to separate the different cultivar groups of V. unguiculata.

Genetic relationships, agronomic, nutritional and technological traits of ten Italian landraces, two improved lines and two cultivars of lentil (Lens culinaris Medik.) were investigated using a multi-disciplinary approach. Seed storage proteins, used as biochemical markers, were able to detect polymorphisms with variability mainly related to the polypeptide abundance. Microsatellite (SSR) molecular markers provided very useful information on genetic variation and relationships among landraces, with polymorphic fragments able to discriminate all the accessions. Lentil landraces were grouped in different clusters and sub-clusters principally on the basis of their geographical origin. The highest levels of genetic diversity were observed for lentils from ‘Castelluccio di Norcia’, ‘Colliano’ and ‘Villalba’. Field trials, performed in two locations of Southern Italy, revealed a high influence of location on yield. Comparing performances at both tested locations, the best landraces were ‘Linosa’ and ‘Valle di Nevola’ suggesting that these have the highest adaptability. Technological and nutritional data together with the agronomic ones evidenced that ‘Linosa’ lentil is the best landrace, however also ‘San Gerardo’ deserves some attention.

This study was carried out to estimate the level of diversity existing within some common bean landraces still cultivated in Nebrodi mountains, North-western area of Sicily. The multidisciplinary approach adopted to reach this goal involved the characterisation of collected material through morphological, biochemical and molecular marker analyses. The nutritional quality of seeds was also investigated in view of the proposition of the best landraces as niche products. Results showed that those bean landraces retain a considerable level of heterogeneity. The use of both biochemical and molecular markers showed that all landraces clustered into two main groups, corresponding to the Andean and Mesoamerican gene pools. Our results suggest that the best strategy for preserving the diversity of common bean from a restricted area such as Nebrodi mountains, necessitates of a deep knowledge of germplasm to avoid the loss of precious genetic resources or, on the contrary, the safeguard of populations genetically redundant.

The primary structure of the double-headed Bowman-Birk inhibitor (BBI) family and the antitryptic activity were investigated in cultivated and wild Phaseolus species. Two BBI types were identified; the first one inhibits trypsin and chymotrypsin (tc-BBI), the second one elastase and trypsin (et-BBI). Only tc-BBI was found in P. lunatus and P. parvulus, while none of BBI types, identified in this study, was found in P. leptostachyus. The deduced amino acid sequences revealed some polymorphisms within both tc-BBI and et-BBI binding loops that could affect the inhibitory activity. The trypsin inhibitor content showed a high variation with the lowest value recorded in P. lepthostachyus and the highest one observed in P. oligospermus. Southern blot analysis confirmed the absence of both BBI types in P. leptostachyus and suggests that in P. coccineus, P. dumosus and P. costaricensis, the two genes were clustered in a narrow genomic region of 1.3kbp.

Efforts to safeguard and promote the on-farm maintenance of common bean (Phaseolus vulgaris L.) landraces should take seed quality into high consideration. Seed quality, in addition to suitable agronomic performances, is a good criterion to identify the most interesting materials among those traditionally cultivated. Ten landraces, still cultivated in the Campania region (southern Italy), were investigated. Five of these landraces, recognized as regional traditional agro-food products, are included in the list of the Italian typical products. Landraces belonging to both Mesoamerican and Andean common bean gene pools were present in the ten studied materials. The harvests of two subsequent growing seasons were analysed in order to compare the physico-chemical, culinary and nutritional seed quality of, recognised or not, landraces. Eighteen agronomic and nutritional traits were scored. When individually considered, none of the scored traits was able to discriminate the two groups of landraces. Conversely, submitting all traits to cluster analysis, two sub-clusters corresponding to recognised or not traditional products were obtained. Two landraces, one for each group, remained isolated. On the bases of these results, it can be inferred that the landraces recognized as traditional agro-food products have different culinary and nutritional characteristics in respect to the non-recognized ones.

Digoxigenated synthetic oligonucleotides complementary tosimple repetitive DNA sequences were used to detect polymorphisms inPhaseolus lunatus L. (Lima bean)genotypes. Twenty two accessions, including wild and cultivatedrepresentatives of the Mesoamerican and Andean gene pools andintermediate forms were included in this study. It could be shownthat five repetitive motifs, namely (AAT)5,(ATG)5,(GACA)4,(GATA)4,(GGAT)4, were able to give clear-cutbands when used as probes and to reveal high levels of variation. Thehighest resolving power was revealed by the(AAT)5 probe, which was able to detect eveninter-individual polymorphisms. Therefore, oligonucleotidefingerprinting has proved to be a useful tool to analyse geneticdiversity in Lima bean. Phylogenetic reconstruction based onJACCARD's similarity index confirmed the existence of two majorgene pools and the presence of a minor group of genetically separatedintermediate genotypes.

Variation of the lectin and the two lectin-related proteins, AIL (α-amylase inhibitor-like) and ARL (arcelin-like) was examined in wild and cultivated accessions of Lima bean (Phaseolus lunatus L.) using electrophoresis of total seed proteins, immunoblot and RFLP analysis of lectin-related genes. Results confirm that divergence of the two major Lima bean gene pools, Andean and Mesoamerican, also apply to this protein family. All three members of the family are present in both gene pools, with differences in size, abundance and composition between gene pools, giving the possibility to distinguish Andean from Mesoamerican lectin pattern types. Both patterns show some variants, such as lack of lectin or its presence as an abundant protein. The observed variation reflects, at least in part, into genomic polymorphism. The presence of arcelin- and α-amylase-related proteins in Lima bean could represent a tool to increase our knowledge in the evolution of the lectin family in Phaseolus species.

Genetic relationships among 13 grasspea (Lathyrus sativus L.) landraces mainly collected in Southern Italy were assessed using agronomic traits, biochemical and molecular markers. Field trials were carried out in two locations and revealed a high influence of field locations on yield, but a low genotype × environment interaction. Despite this, the agronomic data obtained provided useful information for the choice of the best grasspea landraces for southern Italian marginal areas. Seed storage proteins utilised as biochemical markers were not able to detect polymorphisms, on the contrary both classes of molecular markers used i.e. AFLP and SSR, provided useful information on genetic variation and relationships among landraces. Even though the number of polymorphic fragments detected by AFLP technique was low, it was sufficient to discriminate all the accessions. The use of SSR to detect polymorphic sites in grasspea showed that most landraces were clearly grouped in two sub-clusters. One comprised two landraces from most northern localities, while all the other landraces were clustered together at a very narrow genetic distance.

Lectins are a class of defence proteins of non-immune origin that bind carbohydrate in a reversible fashion. In some cultivated legume species, lectin protein coding genes were PCR amplified using primers designed on the basis of conserved N- and C-terminal amino acid sequences of the common bean (one-chain) or pea (two-chains) lectins. Amplification products of the expected length were obtained in Lathyrus sativus L., Vicia faba L. var. major, Phaseolus coccineus L., and Vigna unguiculata (L.) Walp. No amplification product or agglutinating activity against blood cells, and/or cross-reaction with specific antibodies were detected in Lupinus albus L. and Cicer arietinum L. Finally, the new isolated nucleotide sequences, together with other legume lectin sequences already present in the EMBL Database, were used for evolutionary analysis. This last indicated the existence of two main clusters; one grouping all the species belonging to the Phaseoleae tribe and the other one grouping Lens culinaris Medik., Pisum sativum L., L. sativus, and V. faba, members of the Vicieae tribe. Results were congruent with the taxonomic classification and suggested that the lectin genes divergence in legume followed species evolution.

Phaseolin seed protein was used as a marker to reveal the origin, Mesoamerican or Andean, of common bean (Phaseolus vulgaris) accessions cultivated in some countries (Korea, China, and Japan) of eastern Asia. Andean cultivars (T and C phaseolin patterns) are predominant in this geographical area. Introductions from Middle America, represented by cultivars with S phaseolin type, also occurred at lower rate. In all cases, genotypes with larger seeds have been favoured.

Phaseolin variability was analyzed in 86 wild Phaseolus lunatus accessions, representing a wide geographical distribution from Mexico to Argentina, to determine geographical patterns of variability. The collection can be divided into two major groups. One group consists of accessions from Mexico, Central America, Cuba, Columbia, Argentina showing two Mesoamerican (M) phaseolin pattern types, already described in cultivated materials, as well as a variety of additional banding patterns. This suggests that at least two genotypes in the Mesoamerican gene pool were involved in a domestication process and spread throughout the world. The other group, consisting of wild Andean (A) forms from Northern Peru and belonging to the Andean gene pool, showed, among others, two A pattern types comparable to those found in cultivated large-seeded accessions.

Genetic variation inPhaseolus lunatus (Lima bean) was investigated at isozyme and DNA levels. Sixty cultivated accessions, including representatives of the Mesoamerican and Andean gene pools and intermediate types, were analyzed for variability at 17 isozyme loci. Some accessions were also examined for restriction fragment length polymorphism (RFLP) at the rDNA level. These data were used to construct two dendrograms showing clear separation in two distinct groups corresponding to each of the gene pools and an intermediate one probably representing a transitional group.