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91.
The standardized ASCE Penman–Monteith and FAO-56 equations were used to estimate reference evapotranspiration (ET0) using estimated and measured net radiation (Rn) and soil heat flux (G), based on hourly and daily meteorological data. The estimates were evaluated against lysimeter measurements. The results indicate that using measured or estimated values of Rn and G can have significant effect on the accuracy of the ET0 estimations, especially when calculations were made on an hourly basis. The FAO-56 version performed very well during the irrigation season on a daily basis. The use of measured Rn and G did not improve ET0 estimation on a daily basis, therefore, the use of estimated Rn and G appears to be dependable when calculations are based on 24-h weather data. When daily ET0 was calculated from hourly estimations, the results were different depending on the version used. The ASCE version was more accurate, especially when Rn and G were measured. Therefore, measurement of Rn and G may have potential to improve estimation only when daily ET0 is calculated from hourly estimations. The PM FAO-56 version was always a little less accurate than the ASCE version. For hourly calculations, using a constant surface resistance (as in FAO-56 version), the PM method underpredicted for high evaporative demand and vice versa. The ASCE version performed better than PM FAO-56 version when Rn and G were measured and estimated. Therefore, ASCE version tended to provide quite accurate values of hourly ET0, even using estimated values of Rn and G. As conclusion, the methods proposed by FAO-56 for estimating Rn and G tended to produce accurate estimates for daily and hourly ET0 under semiarid conditions and can be used with some degree of confidence for estimating ET0. In addition, results suggest that the ASCE standardized equation on an hourly basis improved the accuracy of ET0 estimation with respect to the FAO-56 version. 相似文献
92.
Uniformity of distribution in irrigation systems plays an important role in the optimum use of irrigation water, with direct repercussions on water-use efficiency and production. To evaluate the effects of the wind on sprinkler water uniformity, it is necessary to measure infield water distribution under different wind conditions and then calculate the parameters that define water distribution. This paper perfects the SIRIAS simulation model for sprinkler systems, which can be used to design new irrigation installations or to improve existing ones. Using ballistic theory to simulate the trajectory of drops discharged by the sprinkler, the model obtains wind-distorted water distribution, with a new formulation for the air drag coefficient. It takes into account three options to distribute the evaporation and drift losses in the irrigation process. SIRIAS software has been programmed using Delphi language for Windows 95, 98 and NT. 相似文献
93.
Lázaro-Lobo Adrián Ramirez-Reyes Carlos Lucardi Rima D. Ervin Gary N. 《Landscape Ecology》2021,36(12):3539-3555
Landscape Ecology - Invasive plants cause significant impacts in forested areas throughout the world. However, little is known about the relative importance of environmental drivers on the... 相似文献
94.
Hector Masuh Andrea Fontn María I. Picollo Susana A. de Licastro Eduardo Zerba 《Pest management science》1996,47(2):181-184
The butyl ester of buthionine sulfoximine (BBSO) applied topically to the nymph V stage of Triatoma infestans (Klug) caused glutathione depletion which was maintained for four days after treatment. Topical pre-treatment of nymph V with BBSO significantly synergised the toxicity of DDT and fenitrothion to T. infestans. 相似文献
95.
Baranowska-Wójcik Ewa Szwajgier Dominik Winiarska-Mieczan Anna 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):30-32
Plant Foods for Human Nutrition - Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized, among others by abnormal levels of acetyl- and butyrylcholinesterase in... 相似文献
96.
Blanch Gracia Patricia Gómez-Jiménez Maria C. del Castillo Maria Luisa Ruiz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):177-183
Plant Foods for Human Nutrition - Grapes contain high contents of phenolics, which are known to possess health promoting properties. Exogenous application of phytoregulators, mainly methyl... 相似文献
97.
Palavecino Pablo Martín Curti María Isabel Bustos Mariela Cecilia Penci María Cecilia Ribotta Pablo Daniel 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(3):326-336
Plant Foods for Human Nutrition - Sorghum is a major cereal crop with various agronomic advantages, contains health-promoting compounds and is gluten-free. There is a growing tendency to use... 相似文献
98.
99.
F. J. Gómez-Gálvez V. Vega-Macías J. C. Hidalgo-Moya J. J. Hidalgo-Moya D. Rodríguez-Jurado 《Plant pathology》2020,69(2):272-283
The application of disinfectants through drip irrigation could be a feasible practice against verticillium wilt (Verticillium dahliae) of olive. OX-VIRIN (activated peroxide) and OX-AGUA AL25 (quaternary ammonium compounds) are two disinfectants that have shown efficacy against V. dahliae in irrigation water and potential for reducing the disease in young olive plants. In this work, various post-planting application strategies incorporating OX-VIRIN (once a month, or twice a month on alternate or successive weeks) or OX-AGUA AL25 (once a month, or twice a month on alternate weeks) were assessed for their effect on V. dahliae in soil, disease in olive trees, and olive yield, in a 2-year pot-experiment under natural environmental conditions. The disinfectants were injected via metering pumps into a drip irrigation system that irrigated olive trees planted in V. dahliae-inoculated soil. All the application strategies significantly reduced the total inoculum density in soil compared to controls with no disinfectants and noninoculated soil. The microsclerotia density was also significantly reduced in disinfested soils by 73.6–86.8%, depending on the strategy. The symptoms and infection incidence were always lower in treatments subjected to disinfestation. The treatment with OX-AGUA AL25 applied twice a month on alternate weeks most reduced the symptoms (by 53.0%) and colonization index (by 70.8%) with respect to untreated water control. This soil disinfestation also significantly strengthened the symptom remission. Tree growth and production were negatively affected by soil inoculation (reduced by 45.6% and 88.7%, respectively), but not so by disinfectants, which even relieved the reduction in inoculated soils, especially when OX-AGUA AL25 was applied. 相似文献
100.
Morlin Carneiro Franciele Angeli Furlani Carlos Eduardo Zerbato Cristiano Candida de Menezes Patricia da Silva Gírio Lucas Augusto Freire de Oliveira Mailson 《Precision Agriculture》2020,21(5):979-1007
Precision Agriculture - Crop monitoring through remote sensing techniques enable greater knowledge of average variability in crop growth. Canopy sensors help provide information on the variability... 相似文献