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WATER NEEDS FOR WINTER BEAN CROP
Klar, A.E.;Fernandes, M.A.;
Scientia Agricola , 1997, DOI: 10.1590/S0103-90161997000200004
Abstract: a study of water use by bean winter crop (phaseolus vulgaris, l., cv. carioca) was carried out in a red yellow latosol, clay texture. a furrow irrigation system maintained soil water potentials higher than -40 kpa. two broadcast nitrogen treatments (0 and 30 kg n/ha) were applied 25 days after planting. the major objectives were to study the nitrogen and evapotranspiration interaction and measure the crop coefficients (kc). the maximum average evapotranspiration (etm) was 1.71 mm/day, or 157.16 mm over 92 days of observations; the etm values for the vegetative (1), flowering (2) and pod formation (3) phases were 1.48, 2.35, and 1.50 mm/day, respectively, for the 30 kg/ha nitrogen treatment, and 1.48, 1.88 and 1.45 mm/day for the no nitrogen treatment. the crop coefficients (kc = etm / eto) were 0.62 and 0.78 for the phase 1, 0.80 and 1.10 for the phase 2, 0.45 and 0.55 for the phase 3 and 0.61 and 0.80 for the entire cycle, based on the fao-penman and class a pan reference methods (eto), respectively. the latter one was the best approach to estimate maximum water use by winter bean crop. nitrogen treatments did not affect evapotranspiration significantly. however, the measured evapotranspiration obtained from the water balance method was 59.78 and 27.12% higher in the flowering than in the vegetative phase, respectively, under 30 and 0 kg n/ha.
WATER NEEDS FOR WINTER BEAN CROP  [cached]
Klar A.E.,Fernandes M.A.
Scientia Agricola , 1997,
Abstract: A study of water use by bean winter crop (Phaseolus vulgaris, L., cv. Carioca) was carried out in a Red Yellow Latosol, clay texture. A furrow irrigation system maintained soil water potentials higher than -40 KPa. Two broadcast nitrogen treatments (0 and 30 kg N/ha) were applied 25 days after planting. The major objectives were to study the nitrogen and evapotranspiration interaction and measure the crop coefficients (Kc). The maximum average evapotranspiration (ETm) was 1.71 mm/day, or 157.16 mm over 92 days of observations; the ETm values for the vegetative (1), flowering (2) and pod formation (3) phases were 1.48, 2.35, and 1.50 mm/day, respectively, for the 30 kg/ha nitrogen treatment, and 1.48, 1.88 and 1.45 mm/day for the no nitrogen treatment. The crop coefficients (Kc = ETm / ETo) were 0.62 and 0.78 for the phase 1, 0.80 and 1.10 for the phase 2, 0.45 and 0.55 for the phase 3 and 0.61 and 0.80 for the entire cycle, based on the FAO-Penman and Class A Pan reference methods (ETo), respectively. The latter one was the best approach to estimate maximum water use by winter bean crop. Nitrogen treatments did not affect evapotranspiration significantly. However, the measured evapotranspiration obtained from the water balance method was 59.78 and 27.12% higher in the flowering than in the vegetative phase, respectively, under 30 and 0 kg N/ha.
Estimating reference evapotranspiration and irrigation water requirements in the Gallikos river basin, Greece
Paltineanu Cr.,Panoras A.G.,Mavroudis I.G.,Louisakis A.
International Agrophysics , 1999,
Abstract: Reference evapotranspiration was calculated using five various types of estimating methods. The Hargreaves and Thornthwaite methods produced close, strongly-correlated ETo values to those yielded by the standard Penman-Monteith method. For these reasons and due to their simplicity in calculations, i.e., few parameters needed, these two methods are recommended for in order to determine crop water as well as irrigation water requirements for the Gallikos watershed. Reference evapotranspiration isolines as yielded by the Hargreaves method showed a characteristic pattern, by decreasing from the eastern to the western part within the Gallikos watershed. Crop water requirements divided crops into more groups. These crops can be an alternative for the present situation which is mainly characterised by wheat cropping. For shortage in irrigation water supply special scenarios, not developed here, should be followed.
Deficit irrigation at different growth stages of the common bean (Phaseolus vulgaris L., cv. Imbabello)
Calvache, M.;Reichardt, K;Bacchi, O.O.S.;Dourado-Neto, D.;
Scientia Agricola , 1997, DOI: 10.1590/S0103-90161997000300002
Abstract: to identify specific growth stages of the common bean crop at which the plant is less sensitive to water stress, in which irrigation could be omitted without significant decrease hi final yield, two field experiments were conducted at "la tola" university experimental station, tumbaco, pichincha, ecuador, on a sandy loam soil (typic haplustoll). the climate is tempered and dry (mean air temperature 16°c and mean relative humidity 74%, during the cropping season) 123 and 109 mm of rainfall were recorded during the experimental cropping periods (july to october), of 1992 and 1994, respectively. the treatments consisted of combinations of 7 irrigation regimes including normal watering; full stress; (traditional management practice); single stress at vegetative stage; flowering; seed formation and ripening, and of 2 levels of applied n (20 and 80 kg/ha). these 14 treatment combinations were arranged and analysed in a split-plot design with 4 replications. the plot size was 33.6 m2 (8 rows, 7 m long) with a plant population of 120,000 pl/ha. irrigation treatments were started after uniform germination and crop establishment soil water content was monitored with a neutron probe down to 0.50 m depth, before and 24 h after each irrigation. the actual evapotranspiration of the crop was estimated by the water-balance technique. field water efficiency and crop water use efficiency were calculated. yield data showed that the treatments which had irrigation deficit had lower yield than those that had supplementary irrigation. the flowering stage was the most sensitive to water stress. nitrogen fertilization significantly increased the number of pods and gram yield. crop water use efficiency (kg/m3) was the lowest with stress at the flowering period, and the yield response factor (ky) was higher hi treatments of full stress and stress at flowering. in relation to the traditional management practice adopted by farmers, only treatments of normal watering and stress at maturation ha
Comparison of different methods in estimating potential evapotranspiration at Muda Irrigation Scheme of Malaysia  [cached]
Nurul Nadrah Aqilah Tukimat,Sobri Harun,Shamsuddin Shahid
Journal of Agriculture and Rural Development in the Tropics and Subtropics , 2012,
Abstract: Evapotranspiration (ET) is a complex process in the hydrological cycle that influences the quantity of runoff and thus the irrigation water requirements. Numerous methods have been developed to estimate potential evapotranspiration (PET). Unfortunately, most of the reliable PET methods are parameter rich models and therefore, not feasible for application in data scarce regions. On the other hand, accuracy and reliability of simple PET models vary widely according to regional climate conditions. The objective of the present study was to evaluate the performance of three temperature-based and three radiation-based simple ET methods in estimating historical ET and projecting future ET at Muda Irrigation Scheme at Kedah, Malaysia. The performance was measured by comparing those methods with the parameter intensive Penman-Monteith Method. It was found that radiation based methods gave better performance compared to temperature-based methods in estimation of ET in the study area. Future ET simulated from projected climate data obtained through statistical downscaling technique also showed that radiation-based methods can project closer ET values to that projected by Penman-Monteith Method. It is expected that the study will guide in selecting suitable methods for estimating and projecting ET in accordance to availability of meteorological data.
Evapotranspiration for Young Cherry Trees (Prunus avium) and Growth Responses to Irrigation  [PDF]
Senih Yazgan,Hakan Buyukcangaz,Cigdem Demirtas,Burak Nazmi Candogan
Pakistan Journal of Biological Sciences , 2006,
Abstract: The goal of this research was to determine the water requirements and effects of different irrigation water application levels on vegetative growth of sweet cherry trees irrigated by a micro-sprinkler system. Evapotranspiration and vegetative growth parameters (tree height, trunk cross-sectional area, volume of trees and branch cross sectional area) of 3-4 years old sweet cherry trees (Prunus avium) were determined during the growing season of 2001 and 2002. The trees were subjected to four irrigation treatments based on adjusted coefficients of Class A pan evaporation (0.50 Epan, 0.75 Epan, 1.00 Epan and 1.25 Epan). Calculated evapotranspiration (ETc) values for irrigation treatments were found as 365-839 mm and 418-840 mm for 2001 and 2002, respectively. The effect of irrigation treatments on total height of tree, trunk cross-sectional area 30 cm above the grafting point, volume of trees and branch cross sectional area were statistically significant at 1% level of probability. When considering the average values of 2001 and 2002, maximum tree height, trunk cross-sectional area, volume of trees and branch cross sectional area were observed at T3 (1.00 Epan) and T4 (1.25 Epan) treatments.
Roots and Nutrient Distribution under Drip Irrigation and Yield of Faba Bean and Onion  [PDF]
Noha A. Mahgoub, Ahmed I. Mohamed, El Sayed M. El Sikhary, Ozoris M. Ali
Open Journal of Soil Science (OJSS) , 2017, DOI: 10.4236/ojss.2017.72004
Abstract: Drip irrigation proved to efficiently provide irrigation water and nutrients to the roots of plants, while maintaining high yield production. This research was established to study the root and nutrient distribution under drip irrigation. Faba bean and onion plants were cultivated in the experimental farm of the Faculty of Agriculture of Suez Canal University in Ismailia city with the application of normal fertilizers to soil. The data showed that soil moisture content in the soil planted with faba bean increased with the horizontal distance between drippers, contrariwise moisture content decreased with horizontal distance with the soil planted with onion. The data showed the vertical distribution of root length, root length density and specific root length of faba bean and onion decreased with increasing soil depth. The data showed that ammonium and nitrate pattern at the soil planted with the both plants increased between drippers and laterals. The peak concentration was recorded 35 mg/kg at 60 - 80 cm soil depth for faba bean and onion, indicating that the NO3-N leaching was low by drip irrigation. Available phosphorus was higher at the surface layer than the subsurface layer at the soil planted with faba bean and onion. Available potassium tended to move both horizontally and downward under drip irrigation.
Infrared thermometry to schedule irrigation of common bean
Lobo, Francisco de Almeida;Oliva, Marco Antonio;Resende, Morethson;Lopes, Nei Fernandes;Maestri, Moacyr;
Pesquisa Agropecuária Brasileira , 2004, DOI: 10.1590/S0100-204X2004000200003
Abstract: the objective of this work was to determine the critical irrigation time for common bean (phaseolus vulgaris l. cv. carioca) using infrared thermometry. five treatments were analyzed. canopy temperature differences between plants and a well-watered control about 1, 2, 3, 4, and 5±0.5oc were tested. physiological variables and plant growth were analyzed to establish the best time to irrigate. there was a significant linear correlation between the index and stomatal resistance, transpiration rate, and leaf water potential. although significant linear correlation between the index and mean values of total dry matter, absolute growth rate, and leaf area index was found, no correlation was found with other growth index like relative growth rate, net assimilation rate, and leaf area ratio. plants irrigated when their canopy temperature was 3±0.5oc above the control had their relative growth rate mean value increased up to 59.7%, yielding 2,260.2 kg ha-1, with a reduction of 38.0% in the amount of water used. plants irrigated when their canopy temperature was 4±0.5oc yielded 1,907.6 kg ha-1, although their relative growth rate mean value was 4.0% below the control. these results show that the best moment to irrigate common bean is when their canopy temperature is between 3oc and 4±0.5oc above the control.
Infrared thermometry to schedule irrigation of common bean
Lobo Francisco de Almeida,Oliva Marco Antonio,Resende Morethson,Lopes Nei Fernandes
Pesquisa Agropecuária Brasileira , 2004,
Abstract: The objective of this work was to determine the critical irrigation time for common bean (Phaseolus vulgaris L. cv. Carioca) using infrared thermometry. Five treatments were analyzed. Canopy temperature differences between plants and a well-watered control about 1, 2, 3, 4, and 5±0.5oC were tested. Physiological variables and plant growth were analyzed to establish the best time to irrigate. There was a significant linear correlation between the index and stomatal resistance, transpiration rate, and leaf water potential. Although significant linear correlation between the index and mean values of total dry matter, absolute growth rate, and leaf area index was found, no correlation was found with other growth index like relative growth rate, net assimilation rate, and leaf area ratio. Plants irrigated when their canopy temperature was 3±0.5oC above the control had their relative growth rate mean value increased up to 59.7%, yielding 2,260.2 kg ha-1, with a reduction of 38.0% in the amount of water used. Plants irrigated when their canopy temperature was 4±0.5oC yielded 1,907.6 kg ha-1, although their relative growth rate mean value was 4.0% below the control. These results show that the best moment to irrigate common bean is when their canopy temperature is between 3oC and 4±0.5oC above the control.
Yield and Yield Components of Faba Bean Genotypes Under Rainfed and Irrigation Conditions  [PDF]
Iyad W. Musallam,Ghazi Al-Karaki,Khalil Ereifej,Abdel Rahman Al-Tawaha
Asian Journal of Plant Sciences , 2004,
Abstract: In this study, thirteen faba bean genotypes were investigated for yield and yield components under rainfed (Maru) and irrigation (JUST) conditions. The results showed that irrigation resulted in a substantial yield increase, more than double that produced under rainfed conditions. The highest seed yield was obtained from genotypes Reina Blanca, L82007-11-3-1, FLIP83-24FB and 80S4387 under both rainfed and irrigation conditions. Higher pods per plant, taller plants, greater hundred seed weight, biological yield, nodule number and nodule dry weight per plant were obtained under irrigation than under rainfed conditions.
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