Frequency Of Water Application Research Articles

Effect of Alternate Furrow Irrigation with Different Irrigation Intervals on Tomato (<i>Lycopersicon E.</i>) Yield and Water Use Efficiency

Experiment was conducted at Eastern Ethiopia of Harari Regional State of Erer Woldiya district, on farmers’ field for two years. The purpose of this study was to evaluate the effect of AFI and EFI with different irrigation intervals on growth component, yield and water use efficiency of tomato for two years 2018 and 2019. Accordingly plant height and NFPP were significantly (P<0.05) influenced by (IMs), whereas (IIs) had highly significant (P<0.01) effect on plant height and NFPP at both planting season. Total tomato yield was significantly influenced (P<0.05) by furrow IMs, but application frequency had highly significant (p<0.01). Water saved from treatment combination of AFI with 4, 6 and 8 days water IIs were 16%, 44% and 58% of total volume of irrigation water applied. Whereas water saved from EFI with 6 and 8 days of application was 33.3% and 50% respectively. AFI with 4 day water application shows little yield reduction as 4.97%, as compared with no stressed treatment; EFI with the same water application frequency). But AFI with 4 day II was saves 16% water from gross water applied for no stressed treatment EFI with 4 day. Treatment with 6 day II of AFI and, EFI were indicated that significant yield reduction as 15.74% and 14.61% respectively. But total amount of gross volume of irrigation water saved as 44 and 33.3% for AFI and EFI of the same II treatment. Crop water productivity (CWUE, IWUE and EWP) were highly significantly (P<0.01) influenced by both IMs and IIs. The result clearly confirms that, AFI had beneficial advantage over EFI on water saving and, the same consequent is happened for irrigation interval i.e. increasing interval from 4 day followed by 6 to 8 days increases water use efficiency of crop. Hence the result indicates that interaction effect of both factors (IMs and IIs) could save significant amount of irrigation water.

The impact of evaporation from porous tile on roof thermal performance: A case study of Guangzhou’s climatic conditions

The evaporative-cooling roof is a popular passive energy conservation technique. This article presents a novel approach for modelling and analysing the influence of evaporation on roof thermal performance. A multivariate nonlinear model was developed for the prediction of the evaporation rate from porous tile. A computer program was then developed based on the one-dimensional roof unsteady heat transfer theory. Finally, the computer program and hourly weather data of Guangzhou, China, were used to analyse the impacts of evaporation (including the evaporation start time and water-application frequency) and slope orientation on roof thermal performance. Evaporation beginning at 11:00 can reduce the external surface temperatures of a horizontal roof and 30°-inclined east-sloping and west-sloping roofs by up to 11.3, 10.7, and 9.8°C, respectively, from those of a non-evaporative roof. This, in turn, can reduce the peak-hour (16:00–20:00) internal surface heat flux. Additionally, with the horizontal roof, the reduction in the peak-hour heat flux can be doubled if the evaporative layer is frequently replenished with water.

Effects of Fertigation and Water Application Frequency on Yield, Water and Fertilizer Use Efficiency of Chili (Capsicum annuum L.).

Effects of Fertigation and Water Application Frequency on Yield, Water and Fertilizer Use Efficiency of Chili (Capsicum annuum L.).

THE EFFECT OF CLOTH TEMPERATURE ON THE COOLING EFFICIENCY OF SHADE CLOTHS IN GREENHOUSES

Tests were conducted to examine the role of cloth temperature in the cooling efficiency of shade cloths appliedto greenhouses. In the first test, shade cloths (with two thermocouples attached to each) were placed over a pair of smallwooden frames, supported by a single layer of clear polyethylene attached to each frame. Water was intermittently appliedto one of the shade cloths every other day. A 60% shade, black cloth was used for the first half of testing and a 40% shade,white cloth was used for the second half. A mathematical model was developed to describe the energy balance on the shadecloths. A second set of tests placed 50% shade, black plastic shade cloths (with six thermocouples attached to each) over two6.7 . 12.2 m, doublepolyethylene covered, Quonsetstyle greenhouses. Water was intermittently applied to one of thegreenhouses on an alternate basis every other day. The greenhouses were kept empty so that energy gain could be determinedby air temperature rise alone. Output from the thermal model was compared to data observed during the shade frame tests.Model output agreed well with the observed shade cloth and floor temperatures, except that floor temperatures under the wetwhite cloth were significantly overpredicted. The model and data showed a clear correlation between shade cloth temperatureand floor temperature. For the greenhouse tests, the data showed that energy gain was directly correlated with shade clothtemperature, and that shade cloth temperature was directly correlated with the frequency of water application. Neither setof tests showed radiation screening by the water film to be a major factor influencing cooling.

Freqüência de irrigação em meloeiro cultivado em solo arenoso

O objetivo deste trabalho foi avaliar o efeito de cinco freqüências de irrigação na produtividade e na eficiência do uso da água em meloeiro cultivado sob fertirrigação por gotejamento em solo arenoso de Tabuleiro Costeiro do Piauí. O delineamento experimental foi em blocos ao acaso, com cinco tratamentos e seis repetições. Os tratamentos foram: F1, F2, F3, F4 e F5, correspondentes às freqüências de irrigação de 0,5, 1, 2, 3 e 4 dias, respectivamente. A freqüência de irrigação influenciou as produtividades comercial e total do meloeiro. As maiores produtividades totais (70,73 t ha-1; 77,99 t ha-1 e 64,21 t ha-1) e comerciais (67,20 t ha-1; 63,88 t ha-1 e 53,67 t ha-1) foram obtidas com as freqüências de 0,5 e de 1 dia, respectivamente. Com aplicações menos freqüentes, houve redução significativa (P&lt;0,01) nas produtividades comercial e total do meloeiro. O peso médio de frutos não foi influenciado pelas freqüências de aplicação de água. A maior e a menor eficiência de uso de água, 24,40 kg m-3 e 14,14 kg m-3, foram obtidas com F1 e F5, respectivamente. As freqüências de irrigação de duas vezes por dia, diária e a cada dois dias, são as recomendadas para o meloeiro cultivado em solo arenoso sob fertirrigação por gotejamento. A eficiência de uso da água no meloeiro é maior quando as freqüências de irrigação são maiores.

Transformation and movement of urea in soil as influenced by water application rate, moisture management regime, and initial moisture content

Abstract Laboratory experiments were conducted to study the influence of water application rate (2.5, 5.0, 7.5, and 10.0 cm), moisture management regime (i.e., frequency of water application), and initial soil moisture content (25, 50, 75, and 100% of field capacity) on the transformation and movement of urea in soil columns. In general, moisture content and the amounts of urea and NH4 +‐N decreased with depth and time at all water application rates. Whereas approximately 79 to 82% of the added urea was hydrolyzed within 48 h, there was no nitrification of the urea‐derived NH4 + within this time period. The application of 1.0, 2.5, 5.0, and 10.0 cm of water resulted in the percolation of water to depths of 33, 36, 39, and 42 cm, respectively. Moisture management had a significant effect on the distribution of N‐species in the soil columns. Increasing the frequency of water additions from one (10.0 cm added on day 1) to ten (additions of 1.0 cm day‐1 for 10 days) resulted in an increase in the amount of urea‐derived NH4 + in the surface layers of the soil, but a decrease in the amount of NO3 ‐‐N in these layers. The initial moisture content of the soil had a considerable effect on the movement of urea. The movement of urea and urea‐derived N into the soil increased with increasing initial soil moisture content, but was restricted to the upper 7 cm of the soil columns. At all soil moisture contents, 60 to 65% of the urea‐derived N was recovered in the top 2 cm of the soil column. In general, the recovery of urea‐derived N from the soil ranged from about 78 to 85%.

Water Quantity and Time of N and K Application for Trickle-irrigated Tomatoes

Abstract Tomatoes (Lycopersicon esculentum Mill.) were grown during two seasons at two locations on fine sands and fine sandy loam soils to study the influence of water quantity, frequency of water application, and timing of N and K application for polyethylene-mulched, trickle-irrigated fresh-market tomatoes. Water quantities were 0.50 and 1.0 times pan evaporation applied one or three times daily. Nitrogen and K were applied 100% preplant or 40% applied preplant and 60% applied with trickle irrigation. Higher tomato leaf tissue N and K concentrations in one of the two seasons and higher fruit yields were obtained with 0.5 than with 1.0 time pan water evaporation on a fine sand at Gainesville, Fla. On a fine sandy loam soil at Quincy, fruit yields were higher in a relatively dry season with the higher water quantity and not influenced by the water quantity applied in the second relatively wet season. The number of daily water applications (one vs. three) at both locations had no effect on N and K uptake or fruit yields. Time of N and K applications had no effect on early yields, but total yields were higher with split than all preplant-applied N and K on the fine sandy soil. Split applications of fertilizer resulted in greater yields of extra-large fruit at mid-season and of extra large and large fruit at late harvest than all preplant-applied fertilizer. On the fine sandy loam soil, time of fertilizer application had no effect on yield.

Field distribution of pesticides applied via a drip irrigation system

A field study was conducted on the application of herbicides via drip irrigation systems. The parameters studied were the rate and frequency of water application. Two herbicides were examined: bromacil — readily soluble and mobile in soils, and napropamide — with low solubility and only slight mobility. Application of these compounds in the field indicated that an increased water application rate results in greater lateral movement. After several weeks of irrigation, surface concentrations of both compounds were found at 30–50 cm from the emitter. Daily irrigation resulted in greater surface accumulation than weekly irrigation, where accumulation deep in the soil profile was found to occur.

Effect of Environment and Genotype on Alfalfa Sprout Production1

Alfalfa (Medicago sativa L.) sprouts are rapidly increasing in popularity in salads and sandwiches in the USA. Methods for growing sprouts are nearly as varied as the number of growers. We examined genetic and environmental influences on germination of alfalfa seed for human consumption. Six cultivars representing a broad range in fall dormancy were germinated under varying environmental conditions including temperature, light duration, amount and frequency of water application, and number of days to harvest. Sprouts were evaluated for fresh weight (yield), nutritional value, and taste acceptability. On a dry weight basis, sprouts were higher in percentage protein than ungerminated seed. Total protein, however, decreased as the seed sprouted. Fresh weight and percentage protein were negatively correlated. Cultivars differed significantly in yield and quality. Sprouts grown for high nutritional value provided a greater percentage of the Recommended Dietary Allowance (RDA) than sprouts grown for high fresh weight. Considering the relatively small nutritional difference between sprouts grown for high fresh weight and high quality, it may be sufficient for sprout growers to concentrate solely on improving fresh weight yield rather than nutritional quality of alfalfa sprouts. Favorable environments are recommended for producing sprouts of either high nutritional quality or high fresh weight.

Factors affecting the accumulation of Dimethoate in soil

The effects of frequency of application, initial soil moisture content, rate of water application and soil organic matter content on the accumulation of dimethoate in different soils have been studied in the laboratory. It was found that: residual accumulation of the pesticide increased with frequency of application (even under leaching conditions) increasing the initial soil moisture content resulted in increased loss by leaching and therefore a reduction in the proportion of pesticide retained in the soil increased frequency of water application favours the loss of pesticide from the soil, thereby reducing the amount retained removal of soil organic matter reduces the biological degradation of the pesticide but accelerates the loss by leaching, evaporation or co‐distillation so that retention is reduced. Some measures are suggested for minimizing the accumulation of dimethoate in soils.

Some factors affecting germination and emergence of sub‐tropical pasture legumes in Rhodesia

Abstract The effect of depth of seeding, moisture stress, shading and mulching on the emergency of a number of sub‐tropical pasture legumes was examined on two contrasting soil types in the greenhouse. The legume species used were Desmodium intortum, D. uncinatum, Glycine wightii, Macroptilium atropurpureum, Stylosanthes guianensis and Trifolium semipilosum. Two contrasting soils were used, a granite‐derived sand and a silt‐rich soil which forms a crust. Surface seeding was unsatisfactory on both soil types and the highest rate of emergence of all species was obtained with sowing depths of 5 or 10 mm. However, several of the legumes, including some with relatively small seeds, were tolerant of deeper sowing on the sandy soil. Differential moisture stress was induced by varying the amount and frequency of water application. These treatments were applied in combination with various shading and mulching treatments. Under conditions of moisture stress both shading and mulching incrsased seedling emergence. On...

The effect of total water supply, and frequency of application, upon lucerne. II.* Chemical composition

Total water supply, expressed as a proportion of class A pan evaporation (Epan), and frequency of water application were varied independently during summer. The phosphorus concentration in the shoots of lucerne increased by 35% when the total water supply was increased from 0.1 to 1.0Epan; the nitrogen concentration was not significantly affected. The in vitro digestibility of leaf and stem fractions decreased with increasing total water supply, and the proportion of highly digestible fractions (leaf and flower) also decreased, so that total shoot digestibility decreased from 65% at 0.24 Epan to 55% at 0.58 Epan. Frequency of water application had no significant effect upon phosphorus or nitrogen concentration or in vitro digestibility. ____________________ *Part I, Aust. J. Agric. Res., 23: 239 (1972)

The effect of total water supply, and frequency of application, upon lucerne. I. Dry matter production

The total quantity of water supplied to an established lucerne stand, and the frequency of water application, were varied independently. The total quantity of water supplied during summer, autumn, and early winter was expressed as a proportion of class A pan evaporation (Epan), and ranged from 0.04 to 3.5 Epan. Dry matter production, at total water supply equal to Epan, varied between 8.6 kg ha-1 day-1 in early winter (May–June) and 97 kg ha-1 day-1 in summer (January–February), and was correlated (r = 0.99) with mean minimum temperature. The form of the response curve of log, dry matter production to water supply, relative to Epan, was similar during all seasons. Dry matter production increased approximately logarithmically with increasing water supply up to the equivalent of 0.5 Epan reached a maximum at about 1.5 Epan, and declined above this. A response surface was constructed, based upon total water supply and mean minimum temperature.Frequency of application, at a given total water supply, had no significant effect on dry matter production when total supply exceeded 0.5 Epan in any season. At a total water supply equal to 0.2 Epan, frequent small applications of water (5 mm) produced 50% more dry matter than less frequent large applications (20 and 80 mm) during summer, but only 30% as much as the less frequent applications in the subsequent autumn. Water use efficiency (ratio of dry matter production to total water supplied) was greatest at 0.5 Epan at all frequencies of application in summer. During the 6 months after irrigation treatments ceased, dry matter production was generally related to the amount of available water in the soil, but production was less, even 18 months later, on plots that had previously received the heaviest irrigation (130mm month-1). Frequency of application had no significant effect upon subsequent yield, but frequent small applications in one summer reduced the capacity of lucerne to extract soil water at low water potentials in the following summer.

Sprinkle and Trickle Irrigation of Green Pepper in an Arid Zone1

Abstract Pepper plants (Capsicum annuum L. cv. California Wonder) were sprinkle and trickle irrigated, each at 2 different frequencies, during the growing season from September to April. Yield, leaf growth, and root development were all greater with trickle than with sprinkle irrigation. Frequency of water application had a slight, but non-significant effect. Yield tended to decrease when the plants were sprinkle irrigated daily. With trickle irrigation, the infrequent interval, every 5 days, tended to reduce the yield. Leaf chloride content was considerably greater under sprinkling, especially at the frequent interval.