Levels of genetic variation and genetic structure of 15 wild populations and three domesticated populations of Capsicum annuum were studied by RAPD markers. A total of 166 bands (all of them polymorphic) and 126 bands (125 of them polymorphic) were amplified in wild and domesticated populations, respectively. Mean percentage of polymorphism was 34.2% in wild populations and 34.7% in domesticated populations. Mean and total genetic diversity were 0.069 and 0.165 for wild populations and 0.081 and 0.131 for domesticated populations. Parameters of genetic diversity estimated from 54 bands with frequencies ‡1 À (3/n) (n = sample size) showed that 56.7% of the total variation was within and 43.3% among wild populations, whereas 67.8% of the variation was within and 32.2% among domesticated populations. AMOVA indicated that total genetic diversity was equally distributed within (48.9 and 50.0%) and among (50.0 and 51.1%) populations in both wild and domesticated samples. Wild and domesticated populations were clearly resolved in a UPGMA dendrogram constructed from Jaccard's distances (average GD = 0.197), as well as by AMOVA (17.2% of variance among populations types, p = 0.001) and by multidimensional scaling analysis. Such differentiation can be associated with domestication as well as different origin of gene pools of the wild (Northwestern Mexico) and cultivated (more probably Central Mexico) samples analyzed. The considerable genetic distances among cultivars (average GD = 0.254) as well as the high number of diagnostic bands per cultivar (33 out of 126 bands), suggest that genetic changes associated with domestication could have resulted from artificial selection intervening in different directions, but the inclusion of more domesticated samples might clarify the nature of distinctions detected here.

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Cereal Chem. 85(6):808-816Nixtamalized and extruded flours from quality protein maize (QPM, V-537C) and tortillas made from them were evaluated for some technological and nutritional properties and compared with the commercial brand MASECA. Both QPM flours showed higher (P < 0.05) protein content, total color difference, pH, available lysine, and lower (P < 0.05) total starch content, Hunter L value, water absorption index, gelatinization enthalpy, resistant starch, and retrograded resistant starch than nixtamalized MASECA flour. Tortillas from nixtamalized and extruded QPM flours had higher contents of essential amino acids than tortillas from MASECA flour, except for leucine. Tortillas from processed QPM flours also showed higher (P < 0.05) values of the nutritional indicators calculated protein efficiency ratio (C-PER 1.80-1.85 vs. 1.04), apparent and true in vivo protein digestibility (78.4-79.1 vs. 75.6% and 76.4-77.4 vs. 74.2%, respectively), PER (2.30-2.43 vs. 1.31), net protein retention (NPR; 2.88-2.89 vs. 2.11), and protein digestibility corrected amino acid score (PDCAAS; 54-55 vs. 29% based on preschool children and 100 vs. 85% based on adults) than MASECA flour. The use of QPM for flour and tortilla preparation may have a positive effect on the nutritional status of people from countries where these products are widely consumed.

Genetic variability of wild populations, closely related to domesticated species, constitute important genetic resources for plant breeding programs. In this paper, we analysed the variation of eight wild populations of Solanum lycopersicum var. cerasiforme in a common garden experiment for levels of plant infestation by whitefly, leaf trichome density as a defensive character preventing infestation by whitefly, and the effect of whitefly incidence into vegetative and reproductive plant characters. Number of adults of whitefly was recorded in the eight wild populations of S. lycopersicum var. cerasiforme, one population of the wild species S. habrochaites (C-360), and one of a cultivated variety of S. lycopersicum (Rio Grande). There were significant differences among the wild populations of S. lycopersicum var. cerasiforme in the average level of whitefly incidence and trichome density. Cultivated tomatoes had the higher incidence of whiteflies (" x = 7.50 ± 0.14) followed by plants of S. lycopersicum var. cerasiforme (" x = 2.02 ± 0.92) and plants of S. habrochaites with the lowest incidence (" x = 0.36 ± 0.35). Whitefly incidence was negatively correlated with trichome density (r = À 0.38, p < 0.0001), suggesting that trichomes deter or limit the establishment of whiteflies. Additionally, a significant negative effect of whitefly incidence along the growing season upon plant growth rate (number of branches and height) and fruit production was detected.

Tomato (Solanum lycopersicum) plants exhibiting symptoms resembling those of permanent yellowing disease (known in Mexico as “permanente del tomate”) that is commonly associated with phytoplasmas (1) were observed in tomato fields in Sinaloa, México in March 2009. Plant symptoms also resembled those caused by “Candidatus Liberibacter solanacearum” infection (2). Affected plants showed an overall chlorosis, severe stunting, leaf cupping, purple discoloration of veins, excessive branching of axillary shoots, and leaf scorching (1,2). Symptom incidence ranged from 18 to 40%. To investigate whether liberibacter is associated with permanent yellowing disease of tomato in México, eight symptomatic and five asymptomatic tomato plants were collected from two fields in La Cruz de Elota and Culiacán, Sinaloa. Total DNA was extracted from the top whole leaf tissue of symptomatic and asymptomatic plants with cetyltrimethylammoniumbromide (CTAB) buffer (3,4). DNA samples were tested by PCR using primer pairs OA2/OI2c and CL514F/CL514R, which amplify a sequence from the 16S rDNA and rplJ and rplL ribosomal protein genes, respectively, of “Ca. L. solanacearum” (2,4). The DNA samples were also tested for phytoplasmas with nested PCR using universal primer pairs P1/P7 and fU5/rU3 (3). DNA from five and four symptomatic plants yielded the expected 1,168-bp 16S rDNA and 669-bp rplJ/rplL amplicons, respectively, indicating the presence of liberibacter. Extracts from asymptomatic plants yielded no products with these primers. Amplicons generated from three symptomatic plants with each primer pair were cloned into pCRII-TOPO plasmid vectors (Invitrogen, Carlsbad, CA) and three clones of each of these amplicons were subsequently sequenced in both directions (ACGT, Inc., Wheeling, IL). BLAST analysis of the 16S rDNA consensus sequence (GenBank Accession No. FJ957897) showed 100% identity to 16S rDNA sequences of “Ca. L. solanacearum” amplified from S. betaceum (EU935004) and S. lycopersicum (EU834130) from New Zealand (2), and “Ca. L. psyllaurous” from potato psyllids (EU812559). The rplJ/rplL consensus sequence (GenBank Accession No. FJ957895) was 100% identical to the analogous rplJ and rplL “Ca. L. solanacearum” ribosomal protein gene sequence amplified from S. lycopersicum (EU834131) from New Zealand (2) and ‘Ca. Liberibacter’ sp. sequence amplified from zebra chip-infected potatoes from Lancaster, CA (FJ498803). No phytoplasmas were detected in the symptomatic tomato plants. To our knowledge, this is the first report of “Ca. L. solanacearum” associated with tomatoes in México. In 2008, this bacterium was detected in glasshouse tomatoes in New Zealand and caused millions of dollars in losses to the commercial glasshouse tomato industry (2). References: (1) R. L. Holguín-Peña et al. Plant Dis. 91:328, 2007. (2) L. W. Liefting et al. Plant Dis. 93:208, 2009. (3) J. E. Munyaneza et al. J. Econ. Entomol. 100:656, 2007. (4) J. E. Munyaneza et al. Plant Dis. 93:552, 2009.

Alcalase hydrolyzates were prepared from the albumin (AH) and globulin (GH) fractions of eight chickpea (Cicer arietinum L.) genotypes from Mexico and 10 from other countries. Protein content, antioxidant activity (AA) (ABTS, DPPH), and degree of hydrolysis were evaluated and the best genotype was selected by principal component analysis. The hydrolyzates of the chosen genotype were analyzed for its antidiabetic potential measured as inhibition of α‐amylase, α‐glucosidase, and dipeptidyl peptidase‐4 (DPP4). Peptide profiles were obtained by liquid chromatography‐mass spectrometry (UPLC‐DAD‐MS), and the most active peptides were analyzed by molecular docking. The average antioxidant activity of albumin hydrolyzates was higher than that of globulin hydrolyzates. ICC3761 was the selected genotype and peptides purified from the albumin hydrolyzate showed the best antioxidant activity and antidiabetic potential (FEI, FEL, FIE, FKN, FGKG, and MEE). FEI, FEL, and FIE were in the same chromatographic peak and this mixture showed the best ABTS scavenging (78.25%) and DPP4 inhibition (IC50 = 4.20 µg/ml). MEE showed the best DPPH scavenging (47%). FGKG showed the best inhibition of α‐amylase (54%) and α‐glucosidase (56%) and may be a competitive inhibitor based on in silico‐predicted interactions with catalytic amino acids in the active site of both enzymes. These peptides could be used as nutraceutical supplements against diseases related to oxidative stress and diabetes. Practical Application This study showed that chickpea protein hydrolyzates are good sources of peptides with antidiabetic potential, showing high antioxidant activity and inhibition of enzymes related to carbohydrate metabolism and type 2 diabetes. These hydrolyzates could be formulated in functional foods for diabetes.

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