14 resultados
Resultados de la búsqueda
Mostrando 1 - 10 de 14
Ítem The effect of hydrothermal treatment on metabolite composition of hass avocados stored in a controlled atmosphere(MDPI, 2021-11-10) Chirinos, Rosana; Campos, David; Martínez, Sofía; Llanos, Sílfida; Betalleluz Pallardel, Indira; García Ríos, Diego; Pedreschi, RominaAvocado cv. Hass consumption has expanded worldwide given its nutritional, sensory, and functional attributes. In this work, avocado fruit from two harvests was subjected to hydrothermal treatment (38 °C for 1 h) or left untreated (control) and then stored for 30 and 50 days in a controlled atmosphere (4 kPa O2 and 6 kPa CO2 at 7 °C) (HTCA and CA, respectively) with subsequent ripening at ~20 °C. The fruit was evaluated for primary and secondary metabolites at harvest, after storage, and after reaching edible ripeness. A decrease from harvest to edible ripeness in mannoheptulose and perseitol was observed while β-sitosterol, hydrophilic and lipophilic antioxidant activity (H-AOX, L-AOX), abscisic acid, and total phenolics (composed of p-coumaric and caffeic acids such as aglycones or their derivatives) increased. HTCA fruit at edible ripeness displayed higher contents of mannoheptulose, perseitol, β-sitosterol, L-AOX, caffeic acid, and p-coumaric acid derivatives, while CA fruit presented higher contents of α-tocopherol, H-AOX, and syringic acid glycoside for both harvests and storage times. The results indicate that a hydrothermal treatment prior to CA enables fruit of high nutritional value characterized by enhanced content of phenolic compounds at edible ripeness to reach distant markets.Ítem Physiological characterization and bioactive compounds of promising accessions of cowpea (Vigna unguiculata L. Walp) in the Peruvian Amazon(Frontiers Media S.A., 2024-05-07) Murga Orrillo, Hipolito; Chuquímez Gonzales, Jhon Kevin; Arévalo López, Luis AlbertoCowpea production in the Peruvian Amazon is increasing due to its ability to adapt to diverse environments, its contribution to soil conservation, and its versatility of uses. This crop is particularly valuable in human nutrition due to its high nutritional quality and nutraceutical properties of its bioactive compounds. The aim of the study was to evaluate the physiology of cowpea plants in accessions PER1005854, PER1005851, and PER12645, under the influence of rice husk mulch, screw tree litter, and oil palm fiber, as well as to determine the bioactive compounds present in the grains. This study aims to promote sustainable cowpea production, expose the nutritional aspects of the grains, and foster their consumption both locally and nationally. The experiment was conducted from November 2022 to March 2023, in Yurimaguas, Loreto, Peru. The application of organic mulches demonstrates a significantly positive impact on the growth of cowpea accessions during their vegetative phase. This effect is possibly attributed to increased water availability, as the mulch reduces soil evaporation. In particular, cowpea accessions PER12645 and PER1005851 exhibit desirable physiological characteristics for grain production, with short cycles of 71 days and higher yields of 1141 and 1125 kg/ha respectively. In contrast, accession PER1005854 is distinguished by its higher biomass production, reaching a value of 14497 kg/ha, a relevant trait for foliage production and its contribution to soil conservation. The bioactive compounds, such as proteins, lipids, and carbohydrates, present in the accessions PER1005854, PER1005851, and PER12645, are similar to those found in other legumes. However, the antioxidant activity of dark tegument cowpeas proved to be superior, particularly highlighted in accession PER12645 (black tegument) with 26.3 μmolTG/g, and in accession PER1005854 (dark red tegument) with 19.5 μmolTG/g. This characteristic is particularly important for consumption, as it is related to the ability to combat oxidative stress in the human body.Ítem Tendencia genética y fenotípica de la producción de leche: caso de un establo comercial del valle de Huaura, Perú(Corporación Colombiana de Investigación Agropecuaria, 2021-03-27) Hidalgo Vásquez, Yaneline Nilda; García Salas, María Elisa Catalina; Gutiérrez Reynoso, Gustavo Augusto; Chagray Ameri, Néstor HumbertoEl objetivo de esta investigación fue determinar la tendencia genética y fenotípica de la producción de leche (PL) de vacas Holstein de un establo del valle de Huaura, Perú. Se evaluaron 2.590 hembras (vacas y terneras) para el cálculo de los valores genéticos estimados (VGE) y 2.862 lactaciones estandarizadas a 305 días y dos ordeños diarios, del primer al quinto parto de 1.892 vacas del periodo 1999-2017, mediante un modelo animal de medidas repetidas. Con el software ASReml, se estimó una heredabilidad (h2) de 0,16 (error estándar 0,03) y una repetibilidad (r) de 0,28 (0,025). Las tendencias se estimaron mediante regresión lineal usando el paquete estadístico SAS v.9.4. Los VGE para la PL de las vacas y terneras tienen una media de +200,9 (16,1) kg y +148,7 (9,7) kg, respectivamente, con más del 70 % de valores positivos. La tendencia genética para PL de las hembras fue -2,4 (2,1) kg/año. Se estimó una tendencia fenotípica para PL de +294,3 (24,9) kg/año. Se concluye que la tendencia fenotípica es favorable debido a mejoras en aspectos no genéticos, ya que la h2 indica que la PL está influenciada principalmente por el ambiente y, en menor medida, por la varianza genética aditiva del carácter. La tendencia genética para la PL de hembras fue negativa. Sin embargo, los VGE para PL de las hembras vivas sugieren que a futuro, el establo puede incrementar la tendencia genética para PL.Ítem Water saving using thermal imagery-based thresholds for timing irrigation in potatoes under drip and furrow irrigation systems(MDPI, 2022-11-23) Rinza, Javier; Ramírez, David A.; Ninanya, Johan; De Mendiburu, Felipe; García, Jerónimo; Quiroz, RobertoUnder the current water crisis in agriculture, irrigation methods for saving and conserving water are necessary. However, these methods must guarantee an appropriate yield with a concomitant economic benefit and a reduced environmental impact. In this study, two irrigation thresholds for irrigation timing (IT) based on thermal imagery were analyzed with the UNICA potato variety in three trials under drip (DI) and furrow (FI) irrigation during 2017–2018 in Lima, Peru. The control (T1) remained at >70% of soil field capacity. For other treatments, thresholds were defined based on stomatal conductance at light saturation (T2: 0.15 and T3: 0.05 mol H2O m−2 s−1) and crop water stress index (T2: 0.4 and T3: 0.6) based on canopy temperature. An integrated index (IIN) was established for the valuation of treatments using the criteria of high fresh tuber yield (FTY) and a low total amount of irrigated water, production cost (PC), and total C emissions (TE) and using criteria of a score. FI-T2 (0.69–0.72) and DI-T3 (0.19–0.29) showed the highest and lowest IIN value, respectively. FTY in T2 was not significantly reduced under FI, resulting in a lower PC regarding DI–T2 and emphasizing the usefulness of thermal imagery in determining watering schedules in potatoes under furrow irrigation systems.Ítem The phylogeography of potato virus X shows the fingerprints of its human vector(MDPI, 2021-09-09) Fuentes, Segundo; Gibbs, Adrian J.; Hajizadeh, Mohammad; Perez, Ana; Adams, Ian P.; Fribourg, Cesar E.; Kreuze, Jan; Fox, Adrian; Boonham, Neil; Jones, Roger A. C.Potato virus X (PVX) occurs worldwide and causes an important potato disease. Complete PVX genomes were obtained from 326 new isolates from Peru, which is within the potato crop′s main domestication center, 10 from historical PVX isolates from the Andes (Bolivia, Peru) or Europe (UK), and three from Africa (Burundi). Concatenated open reading frames (ORFs) from these genomes plus 49 published genomic sequences were analyzed. Only 18 of them were recombinants, 17 of them Peruvian. A phylogeny of the non-recombinant sequences found two major (I, II) and five minor (I-1, I-2, II-1, II-2, II-3) phylogroups, which included 12 statistically supported clusters. Analysis of 488 coat protein (CP) gene sequences, including 128 published previously, gave a completely congruent phylogeny. Among the minor phylogroups, I-2 and II-3 only contained Andean isolates, I-1 and II-2 were of both Andean and other isolates, but all of the three II-1 isolates were European. I-1, I-2, II-1 and II-2 all contained biologically typed isolates. Population genetic and dating analyses indicated that PVX emerged after potato’s domestication 9000 years ago and was transported to Europe after the 15th century. Major clusters A–D probably resulted from expansions that occurred soon after the potato late-blight pandemic of the mid-19th century. Genetic comparisons of the PVX populations of different Peruvian Departments found similarities between those linked by local transport of seed potato tubers for summer rain-watered highland crops, and those linked to winter-irrigated crops in nearby coastal Departments. Comparisons also showed that, although the Andean PVX population was diverse and evolving neutrally, its spread to Europe and then elsewhere involved population expansion. PVX forms a basal Potexvirus genus lineage but its immediate progenitor is unknown. Establishing whether PVX′s entirely Andean phylogroups I-2 and II-3 and its Andean recombinants threaten potato production elsewhere requires future biological studies.Ítem Mass spectrometry-based flavor monitoring of Peruvian chocolate fabrication process(MDPI, 2021-01-26) Michel, Stephanie; Baraka, Luka Franco; Ibañez, Alfredo J.; Mansurova, MadinaFlavor is one of the most prominent characteristics of chocolate and is crucial in determining the price the consumer is willing to pay. At present, two types of cocoa beans have been characterized according to their flavor and aroma profile, i.e., (1) the bulk (or ordinary) and (2) the fine flavor cocoa (FFC). The FFC has been distinguished from bulk cocoa for having a great variety of flavors. Aiming to differentiate the FFC bean origin of Peruvian chocolate, an analytical methodology using gas chromatography coupled to mass spectrometry (GC-MS) was developed. This methodology allows us to characterize eleven volatile organic compounds correlated to the aromatic profile of FFC chocolate from this geographical region (based on buttery, fruity, floral, ethereal sweet, and roasted flavors). Monitoring these 11 flavor compounds during the chain of industrial processes in a retrospective way, starting from the final chocolate bar towards pre-roasted cocoa beans, allows us to better understand the cocoa flavor development involved during each stage. Hence, this methodology was useful to distinguish chocolates from different regions, north and south of Peru, and production lines. This research can benefit the chocolate industry as a quality control protocol, from the raw material to the final product.Ítem Unraveling ecophysiological mechanisms in potatoes under different irrigation methods: a preliminary field evaluation(MDPI, 2020-06-11) Silva Díaz, Cecilia; Ramírez, David A.; Rodríguez Delfín, Alfredo; De Mendiburu, Felipe; Rinza, Javier; Ninanya, Johan; Loayza, Hildo; Quiroz, RobertoPotatoes—a global food security and staple crop—is threatened by dry spells in drought-prone areas. The use of physiological thresholds to save water while maintaining a reasonable tuber yield has been proposed, but their effects on physiological performances and usefulness under different irrigation methods are yet to be evaluated. In this study, photosynthetic traits were monitored to assess the effect of water restriction and rewatering under drip (DI) and furrow (FI) irrigations. The treatments consisted of two maximum light-saturated stomatal conductance (g𝑠_𝑚𝑎𝑥) irrigation thresholds (T2: 0.15 and T3: 0.05 mol H2O m−2 s−1) compared with a fully irrigated control (g𝑠_𝑚𝑎𝑥 > 0.3 mol H2O m−2 s−1). DI used less water than FI but promoted early senescence and low percentage of maximum assimilation rate (PMA) at late developmental stages. FI caused no yield penalization in T2 and higher recovery of carbon isotope discrimination and PMA than DI. It is suggested that moderate water quantities of early and frequently water pulses in the irrigation, promote short-term water stress memory improvement, senescence delay and more capability of recovery at late stages.Ítem Canopy temperature as a key physiological trait to improve yield prediction under water restrictions in potato(MDPI, 2021-07-20) Ninanya, Johan; Ramírez, David A.; Rinza, Javier; Silva-Díaz, Cecilia; Cervantes, Marcelo; García, Jerónimo; Quiroz, RobertoCanopy temperature (CT) as a surrogate of stomatal conductance has been highlighted as an essential physiological indicator for optimizing irrigation timing in potatoes. However, assessing how this trait could help improve yield prediction will help develop future decision support tools. In this study, the incorporation of CT minus air temperature (dT) in a simple ecophysiological model was analyzed in three trials between 2017 and 2018, testing three water treatments under drip (DI) and furrow (FI) irrigations. Water treatments consisted of control (irrigated until field capacity) and two-timing irrigation based on physiological thresholds (CT and stomatal conductance). Two model perspectives were implemented based on soil water balance (P1) and using dT as the penalizing factor (P2), affecting the biomass dynamics and radiation use efficiency parameters. One of the trials was used for model calibration and the other two for validation. Statistical indicators of the model performance determined a better yield prediction at harvest for P2, especially under maximum stress conditions. The P1 and P2 perspectives showed their highest coefficient of determination (R2) and lowest root-mean-squared error (RMSE) under DI and FI, respectively. In the future, the incorporation of CT combining low-cost infrared devices/sensors with spatial crop models, satellite image information, and telemetry technologies, an adequate decision support system could be implemented for water requirement determination and yield prediction in potatoes.Ítem In-depth genetic diversity and population structure of endangered Peruvian Amazon rosewood germplasm using Genotyping by Sequencing (GBS) technology(MDPI, 2021-02-08) Azhar Nadeem, Muhammad; Vasquez Guizado, Stalin Juan; Qasim Shahid, Muhammad; Amjad Nawaz, Muhammad; Habyarimana, Ephrem; Ercişli, Sezai; Ali, Fawad; Karaköy, Tolga; Aasim, Muhammad; Hatipoğlu, Rüştü; Castro Gómez, Juan Carlos; Marapara Del Aguila, Jorge Luis; Adrianzén Julca, Pedro Marcelino; Torres Canales, Esperanza; Hwan Yang, Seung; Chung, Gyuhwa; Shehzad Baloch, FaheemResearch studies on conservative genetics of endangered plants are very important to establish the management plans for the conservation of biodiversity. Rosewood is an evergreen tree of the Amazon region and its essential oil has great acceptance in the medical and cosmetic industry. The present study aimed to explore the genetic diversity and population structure of 90 rosewood accessions collected from eight localities of Peruvian Amazon territory through DArTseq markers. A total of 7485 informative markers resulted from genotyping by sequencing (GBS) analysis were used for the molecular characterization of rosewood germplasm. Mean values of various calculated diversity parameters like observed number of alleles (1.962), the effective number of alleles (1.669), unbiased expected heterozygosity (0.411), and percent polymorphism (93.51%) over the entire germplasm showed the existence of a good level of genetic variations. Our results showed that the Mairiricay population was more diverse compared to the rest of the populations. Tamshiyacu-2 and Mairiricay-15 accessions were found genetically distinct accessions. The analysis of molecular variance (AMOVA) reflected maximum variations (75%) are due to differences within populations. The implemented clustering algorithms, i.e.; STRUCTURE, neighbor-joining analysis and principal coordinate analysis (PCoA) separated the studied germplasm on the basis of their geographical locations. Diversity indices for STRUCTURE-based populations showed that subpopulation A is more diverse population than the rest of the populations, for such reason, individuals belonging to this subpopulation should be used for reintroduction or reinforcement plans of rosewood conservation. We envisage that molecular characterization of Peruvian rosewood germplasm with DArTseq markers will provide a platform for the conservation, management and restoration of endangered rosewood in upcoming years.Ítem Development of an open-source thermal image processing software for improving irrigation management in potato crops (Solanum tuberosum L.)(MDPI, 2020-01-14) Cucho Padin, Gonzalo; Rinza, Javier; Ninanya, Johan; Loayza, Hildo; Quiroz, Roberto; Ramirez, David A.Accurate determination of plant water status is mandatory to optimize irrigation scheduling and thus maximize yield. Infrared thermography (IRT) can be used as a proxy for detecting stomatal closure as a measure of plant water stress. In this study, an open-source software (Thermal Image Processor (TIPCIP)) that includes image processing techniques such as thermal-visible image segmentation and morphological operations was developed to estimate the crop water stress index (CWSI) in potato crops. Results were compared to the CWSI derived from thermocouples where a high correlation was found (𝑟𝑃𝑒𝑎𝑟𝑠𝑜𝑛 = 0.84). To evaluate the effectiveness of the software, two experiments were implemented. TIPCIP-based canopy temperature was used to estimate CWSI throughout the growing season, in a humid environment. Two treatments with different irrigation timings were established based on CWSI thresholds: 0.4 (T2) and 0.7 (T3), and compared against a control (T1, irrigated when soil moisture achieved 70% of field capacity). As a result, T2 showed no significant reduction in fresh tuber yield (34.5 ± 3.72 and 44.3 ± 2.66 t ha−1), allowing a total water saving of 341.6 ± 63.65 and 515.7 ± 37.73 m3 ha−1 in the first and second experiment, respectively. The findings have encouraged the initiation of experiments to automate the use of the CWSI for precision irrigation using either UAVs in large settings or by adapting TIPCIP to process data from smartphone-based IRT sensors for applications in smallholder settings.