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Item type: Item , Strategic modulation of lime concentration to optimize chemical composition, microbial stability, and sensory quality in quispiño dough formulation(Springer Nature, 2025) Mindani, C.G.; Ibañez, V.; Baldeón, E.O.; Cahuana, J.L.; Calizaya, F.G.; Areche, F.O.; Paricanaza, D.C.; Barrera, J.M.; Castro, D.H.; Luque, O.M.; Choque, T.J.; Corilla, D.D.; Calla, M.A.This study investigates the impact of varying lime concentrations (0.1–0.9%) on the chemical composition, microbial stability, color, texture, and sensory properties of quispiño dough. Lime concentrations ranging from 0.1 to 0.9% were analyzed. The results demonstrated that higher lime concentrations significantly reduced moisture, protein, pH, total phenols, fat, and fiber content, while increasing ash content. Microbial stability improved with higher lime concentrations, leading to substantial reductions in total viable count (TVC), yeast, mold, and the complete absence of E. coli at concentrations of 0.5% and above. Color analysis revealed a decrease in lightness (L) and increases in redness (a) and yellowness (b), especially after cooking. Texture profile analysis (TPA) indicated that higher lime levels led to softer dough, characterized by reduced hardness, elasticity, and cohesiveness. Sensory evaluation confirmed that the overall acceptability of the dough decreased as lime concentration increased, with significant declines in flavor, texture, and appearance at concentrations above 0.5%. Results revealed lime enhances microbial stability and alters the chemical composition of quispiño dough, it can also negatively impact its sensory qualities at higher concentrations above 0.5%. A balance between functional benefits and consumer acceptability is therefore critical when using lime in dough formulations. This study provides valuable insights for both traditional and industrial food applications where lime is used as a natural preservative and processing aid. Striking a balance between functional benefits and consumer acceptability is critical when incorporating lime in quispiño dough. Optimizing lime concentration is essential to balance functional benefits and consumer acceptability in quispiño dough production.Item type: Item , Nuclear ribosomal internal transcribed spacer 1 (ITS1) variation in the Anastrepha fraterculus cryptic species complex (Diptera, Tephritidae) of the Andean region(Pensoft Publishers, 2015) Sutton, B.D.; Steck, G.J.; Norrbom, A.L.; Rodriguez, E.J.; Srivastava, P.; Alvarado, N.N.; Colque, F.; Landa, E.Y.; Sánchez, J.J.L.; Quisberth, E.; Peñaranda, E.A.; Rodriguez Clavijo, P.A.; Alvarez-Baca, J.K.; Zapata, T.G.; Ponce, P.The nuclear ribosomal internal transcribed spacer 1 (ITS1) was sequenced for Anastrepha fraterculus (Wiedemann, 1830) originating from 85 collections from the northern and central Andean countries of South America including Argentina (Tucumán), Bolivia, Perú, Ecuador, Colombia, and Venezuela. The ITS1 regions of additional specimens (17 collections) from Central America (México, Guatemala, Costa Rica, and Panamá), Brazil, Caribbean Colombia, and coastal Venezuela were sequenced and together with published sequences (Paraguay) provided context for interpretation. A total of six ITS1 sequence variants were recognized in the Andean region comprising four groups. Type I predominates in the southernmost range of A. fraterculus. Type II predominates in its northernmost range. In the central and northern Andes, the geographic distributions overlap and interdigitate with a strong elevational effect. A discussion of relationships between observed ITS1 types and morphometric types is included.Item type: Item , Characterization of a Peruvian isolate of Metarhizium anisopliae var. acridum, a pathogen of grasshoppers(Embrapa, 2003) Magalhães, B.P.; Tigano, M.S.; Martins, I.; Frazão, H.; Ramirez, H.G.The objective of this study was to characterize the Peruvian isolate of Metarhizium anisopliae var. acridum, CG 863, obtained from the grasshopper Schistocerca interrita, a crop pest in Peru. The characterization was done by comparing this isolate with two other ones of M. anisopliae var. acridum, from Brazil and Australia, and with an isolate of M. anisopliae var. anisopliae. The three M. anisopliae var. acridum isolates had similar growth profiles in agar plates at 25°C and 37°C, and similar RAPD patterns according to the analysis of three primers. However, regarding these parameters and conidial size, these isolates were very distinct when compared to M. anisopliae var. anisopliae isolate. Bioassays indicated that the Peruvian isolate is as pathogenic as the Brazilian isolate against nymphs of Rhammatocerus schistocercoides.Item type: Item , Marker-free PLRV resistant potato mediated by Cre-loxP excision and RNAi(Springer, 2016) Orbegozo, J.; Solorzano, D.; Cuellar, W.J.; Bartolini, I.; Roman, M.L.; Ghislain, M.; Kreuze, J.An inverted repeat construct corresponding to a segment of the potato leaf roll virus coat protein gene was created under control of a constitutive promoter and transferred into a transformation vector with a heat inducible Cre-loxP system to excise the nptII antibiotic resistance marker gene. Fifty-eight transgenic events were evaluated for resistance to PLRV by greenhouse inoculations, which lead to the identification of 7 highly resistant events, of which 4 were extremely resistant. This resistance was also highly effective against accumulation in subsequent tuber generations from inoculated plants, which has not been reported before. Northern blot analysis showed correlation of PLRV specific siRNA accumulation with the level of PLRV resistance. Heat mediated excision of the nptII antibiotic resistance gene in PLRV resistant events was highly efficient in one event with full excision in 71 % of treated explants. On the other hand 8 out of 10 analyzed events showed truncated T-DNA insertions lacking one of the two loxP sites as determined by PCR and confirmed by sequencing flanking regions in 2 events, suggesting cryptic LB sites in the non-coding region between the nptII gene and the flanking loxP site. Accordingly, it is proposed to modify the Cre-loxP vector by reducing the 1 kb size of the region between nptII, loxP, and the LB.Item type: Item , Molecular and genetic characterization of the Ryadg locus on chromosome XI from Andigena potatoes conferring extreme resistance to potato virus Y(Springer, 2018) Herrera, M.R.; Vidalon, L.J.; Montenegro, J.D.; Riccio, C.; Guzman, F.; Bartolini, I.; Ghislain, M.Key message: We have elucidated the Andigena origin of the potato Ryadg gene on chromosome XI of CIP breeding lines and developed two marker assays to facilitate its introgression in potato by marker-assisted selection. Abstract: Potato virus Y (PVY) is causing yield and quality losses forcing farmers to renew periodically their seeds from clean stocks. Two loci for extreme resistance to PVY, one on chromosome XI and the other on XII, have been identified and used in breeding. The latter corresponds to a well-known source of resistance (Solanum stoloniferum), whereas the one on chromosome XI was reported from S. stoloniferum and S. tuberosum group Andigena as well. To elucidate its taxonomic origin in our breeding lines, we analyzed the nucleotide sequences of tightly linked markers (M45, M6) and screened 251 landraces of S. tuberosum group Andigena for the presence of this gene. Our results indicate that the PVY resistance allele on chromosome XI in our breeding lines originated from S. tuberosum group Andigena. We have developed two marker assays to accelerate the introgression of Ryadg gene into breeding lines by marker-assisted selection (MAS). First, we have multiplexed RYSC3, M6 and M45 DNA markers flanking the Ryadg gene and validated it on potato varieties with known presence/absence of the Ryadg gene and a progeny of 6,521 individuals. Secondly, we developed an allele-dosage assay particularly useful to identify multiplex Ryadg progenitors. The assay based on high-resolution melting analysis at the M6 marker confirmed Ryadg plex level as nulliplex, simplex and duplex progenitors and few triplex progenies. These marker assays have been validated and can be used to facilitate MAS in potato breeding.
