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61.
Kelly vila‐Mndez Rodrigo Avila‐Diazgranados Alonso Pardo Mariana Herrera Greicy Sarria Hernan Mauricio Romero 《Forest Pathology》2019,49(2)
Bud rot (BR) disease caused by Phytophthora palmivora is the most devastating disease in oil palm cultivation in America. Oil palms that survived BR epidemics were found in areas highly devastated by the disease; these palms were introduced into Cenipalma's in vitro micropropagation (cloning programme). A severity scale was developed for in vitro palms from five ortets inoculated with two different P. palmivora isolates. Then, eight ortets of Elaeis guineensis and two ortets of the OxG interspecific hybrid were evaluated in two inoculation trials under chamber growth conditions. The clone performance response was consistent with that reported in the field for the corresponding ortets, and two contrasting ortets, one susceptible (ortet 57) and one resistant (ortet 34) were identified. We monitored and compared defence responses to P. palmivora in the contrasting ortets. An increase in reactive oxygen species (ROS) production after inoculation with the pathogen was observed, with higher accumulation of H2O2 in the resistant plants. Catalase (CAT) activity in resistant plants increased after inoculation with the pathogen from 24 hr post‐infection (hpi) and remained high during the observation time. In the susceptible ortets, there was a significant increase on catalase activity only at 48 hpi. Peroxidase (POS) activity increased in clones from both susceptible and resistant ortets, but the increase was much greater in the susceptible ones. Phenylalanine ammonia lyase activity increased in response to inoculation, and these increases were greater in clones of the susceptible ortet than in clones of the resistant ortet. 相似文献
62.
New Forests - Pinus pinea is an interesting species for its valued pine nuts. Despite the high demand for this nut, the species is mostly harvested from natural forests, because the time elapsed... 相似文献
63.
Silva RD Bueno AL Gallon CW Gomes LF Kaiser S Pavei C Ortega GG Kucharski LC Jahn MP 《Fitoterapia》2011,82(6):818-826
This study analyzed the plasma lipid profile, glucose levels and fat deposits in male rats treated with aqueous extract of gross yerba mate, commercial yerba mate or water. Yerba mate treatment did not change body weight gain and lipid profile. The consumption of gross yerba mate significantly increased blood glucose (6.6 mmol/L) as compared to the water (4.8 mmol/L) and commercial group (5.2 mmol/L) and decreased epididymal and intra-abdominal deposits (10.1 mg/g and 23.7 mg/g of weight) as compared to the water (15.4 mg/g and 36.9 mg/g of weight) and commercial group (12.5 mg/g and 28 mg/g of weight). The results suggest that gross yerba mate reduces fat more efficiently but produces a greater increase in blood glucose when compared to commercial yerba mate and water groups. 相似文献
64.
Energy analysis of irrigation delivery systems: monitoring and evaluation of proposed measures for improving energy efficiency 总被引:1,自引:1,他引:1
M. A. Moreno J. F. Ortega J. I. Córcoles A. Martínez J. M. Tarjuelo 《Irrigation Science》2010,28(5):445-460
In Spain, the Ministry of Industry is implementing actions for analyzing the energy efficiency of Water User Associations
(WUAs) by using energy indicators and proposing measures to improve the use of energy. The main objective of this work was
to develop tools to improve energy efficiency in WUAs. These tools were validated by utilizing them in the energy analysis
of 15 WUAs located in Castilla-La Mancha Region (Spain) during the 2007 irrigation season. These tools were also utilized
for the proposal of measures to improve the use of energy. The proposed measures were monitored and evaluated in 7 of the
15 WUAs during the 2008 irrigation season. The developed tools were integrated into a Decision Support System for performing
energy analysis and for proposing measures of energy efficiency improvement. In most of the study cases, an improvement of
the energy efficiency after the implementation of the proposed measures was detected, with an average energy saving of the
10.2%. 相似文献
65.
The factors influencing the decision of smallholder farmers to adopt new farming technologies were studied with reference to rubber–tea intercropping in Sri Lanka. Rubber–tea intercropping has been recommended previously to rubber farmers as a means to improve productivity and income during the early pre-tapping phase of rubber growth. Although crop trials have shown that the two crops are agronomically compatible and potentially produce a combined economic yield superior to the yield of a sole crop grown on the same area of land, there is little evidence of widespread adoption of this practice among smallholder farmers in Sri Lanka. The aim of the study was to determine the major factors that influence the decision to undertake rubber–tea intercropping and to construct a predictive model that describes the likelihood of adoption of intercropping by traditional smallholder rubber growers. A rapid rural appraisal (RRA) was undertaken based on semi-structured interviews of 90 smallholder farmers in the main rubber growing low wet zone of Sri Lanka. Among a number of factors shown to significantly influence the decision to intercrop tea with rubber, three were shown to operate independently, namely level of income, source of income (i.e. solely from own farm or from farm plus additional off-farm enterprises), and availability of land considered suitable for tea cultivation. A statistical model developed through correlation and logistic analysis, which predicts the likelihood of a smallholder adopting intercropping based on these factors, is presented and discussed. The most likely combination of circumstances (82% probability) under which rubber–tea intercropping is practiced is shown to be where the farmer’s income is greater than Rs. 10,000 per month, where the farmer’s income is based solely on own farm enterprises, and where more than 80% of the farmer’s land area was judged to be suitable for tea cultivation. Conversely, 30% of smallholder farmers that chose not to intercrop did possess land suitable for tea cultivation. Qualitative responses to the RRA indicated that limitation of technical knowledge was the main problem subsequently faced by rubber farmers who had adopted rubber–tea intercropping. Results indicate that there is need for both income support through farm subsidies and further agricultural extension services, if rubber–tea intercropping is to be adopted more widely in Sri Lanka. The wider usefulness of the developed logistic model in determining the likelihood of adoption of intercropping by smallholder farmers is discussed. 相似文献
66.
67.
Joaquín R. Domínguez T. González P. Palo J. Sánchez-Martín M. A. Rodrigo C. Sáez 《Water, air, and soil pollution》2012,223(5):2685-2694
In this work, the electrochemical treatment of an effluent from the pharmaceutical industry with boron-doped diamond electrodes was investigated. The electrolyses were carried out in a discontinuous operation mode under galvanostatic conditions, using a bench-scale plant equipped with a single-compartment electrochemical flow cell. The effect of operating conditions, such as current density (from 25.7 to 179.4?mA?cm2) and flow rate (from 104.8 to 564.7?cm3?min?1), at residence times between 0 and 570?min, was studied. Design of experiments was used for optimizing the process. The global contribution of operative parameters and evolution of the residence time in TOC removal was studied, and a time of 77?min was obtained in order to evaluate the highest influence of the operative parameters. For this time, ANOVA test reported significance for four of the five involved variables. The current density was found to have a considerable positive effect on TOC removal, whereas the flow rate was found to have a moderate negative effect on target variable. 相似文献
68.
Feliciano RP Shea MP Shanmuganayagam D Krueger CG Howell AB Reed JD 《Journal of agricultural and food chemistry》2012,60(18):4578-4585
The 4-(dimethylamino)cinnamaldehyde (DMAC) assay is currently used to quantify proanthocyanidin (PAC) content in cranberry products. However, this method suffers from issues of accuracy and precision in the analysis and comparison of PAC levels across a broad range of cranberry products. Current use of procyanidin A2 as a standard leads to an underestimation of PACs content in certain cranberry products, especially those containing higher molecular weight PACs. To begin to address the issue of accuracy, a method for the production of a cranberry PAC standard, derived from an extraction of cranberry (c-PAC) press cake, was developed and evaluated. Use of the c-PAC standard to quantify PAC content in cranberry samples resulted in values that were 2.2 times higher than those determined by procyanidin A2. Increased accuracy is critical for estimating PAC content in relationship to research on authenticity, efficacy, and bioactivity, especially in designing clinical trials for determination of putative health benefits. 相似文献
69.
Raquel Sánchez-Pérez Encarnación Ortega Henri Duval Pedro Martínez-Gómez Federico Dicenta 《Euphytica》2007,155(3):381-391
The inheritance of 16 important agronomic traits and its relationship were studied for four years in a population of 167 almond
[P. dulcis (Mill.) D.A. Webb] seedlings obtained from a cross between the French selection ‘R1000’ (‘Tardy Nonpareil’ × ‘Tuono’) and
the Spanish cultivar ‘Desmayo Largueta’. For some traits (blooming and leafing date) descendants segregated between the value
of both progenitors, meanwhile for others the mean of the offspring was lower (bloom density, productivity and ripening date)
or higher (in-shell/kernel ratio and double kernels). As expected, kernel bitterness and self-incompatibility behaved as monogenic
traits. Some important correlations between traits were detected. The implications of the transmission and the correlation
of these traits in the breeding programmes are discussed. 相似文献
70.
José Maria Villela Pádua Kaio Olímpio Das Graças Dias Maria Marta Pastina João Cândido de Souza Valéria Aparecida Vieira Queiroz Rodrigo Veras da Costa Maria Beatriz Pereira da Silva Carlos Alexandre Gomes Ribeiro Claudia Teixeira Guimarães Salvador Alejandro Gezan Lauro José Moreira Guimarães 《Euphytica》2016,211(3):277-285