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Seed morphometric and -colorimetric features describing shape, size and textural seed traits of 28 taxa belonging to the genera Lavatera L. and Malva L., were recorded by means of computer vision techniques. The data were statistically analysed to contribute to the taxonomical treatment of the Malva alliance and to assess some doubtful systematic positions. A clear differentiation between taxa traditionally attributed to Lavatera or Malva was highlighted. Furthermore, the identification system proposed here was able to discriminate among the Lavatera sections, confirming the taxonomic organization of this genus. The results obtained for Malva, both at the species level and among sections, supported this analytical tool as diagnostic for systematic purposes.

The primary structures of high molecular weight glutenin subunits (HMW-GS) of 5 Triticum durum Desf. cultivars (Simeto, Svevo, Duilio, Bronte, and Sant'Agata), largely cultivated in the south of Italy, and of 13 populations of the old spring Sicilian durum wheat landrace Timilia (Triticum durum Desf.) (accession nos. 1, 2, 3, 4, 7, 8, 9, 13, 14, 15, SG1, SG2, and SG3) were investigated using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and reversed-phase high performance liquid chromatography/nanoelectrospray ionization mass spectrometry (RP-HPLC/nESI-MS/MS). M(r) of the intact proteins determined by MALDI mass spectrometry showed that all the 13 populations of Timilia contained the same two HMW-GS with 75.2 kDa and 86.4 kDa, whereas the other durum wheat cultivars showed the presence of the expected HMW-GS 1By8 and 1Bx7 at 75.1 kDa and 83.1 kDa, respectively. By MALDI mass spectrometry of the tryptic digestion peptides of the isolated HMW-GS of Timilia, the 1Bx and 1By subunits were identified as the NCBInr Acc. No AAQ93629, and AAQ93633, respectively. Sequence verification for HMW-GS 1Bx and 1By both in Simeto and Timilia was obtained by MALDI mass mapping and HPLC/nESI-MSMS of the tryptic peptides. The Bx subunit of Timila presents a sequence similarity of 96% with respect to Simeto, with differences in the insertion of 3 peptides of 5, 9, and 15 amino acids, for a total insertion of 29 amino acids and 25 amino acid substitutions. These differences in the amino acidic sequence account for the determined Δm of 3294 Da between the M(r) of the 1Bx subunits in Timilia and Simeto. Sequence alignment between the two By subunits shows 10 amino acid substitutions and is consistent with the Δm of 148 Da found in the MALDI mass spectra of the intact subunits.

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Deoxynivalenol, zearalenone, and aflatoxin concentrations in Sicilian durum wheat were determined through ELISA tests. The results highlighted the safety of the grain samples at harvest because deoxynivalenol, zearalenone, and aflatoxin levels did not exceed European legal limits. With regard to aflatoxins, reliability of the ELISA test was evaluated, comparing it with HPLC analyses. The comparison of HPLC and ELISA data showed a tendency to overestimate aflatoxin concentrations with respect to chromatographic determinations. The usefulness of ELISA was confirmed as a rapid screening method; however, when contamination levels are close to legal limits, chromatographic analyses are necessary to quantify aflatoxins with greater accuracy and specificity.