Responses of Tea (Camellia sinensis) to Irrigation and Fertilizer. II. water Use

1991 ◽  
Vol 27 (2) ◽  
pp. 193-210 ◽  
Author(s):  
William Stephens ◽  
M. K. V. Carr
Keyword(s):  
Water Use ◽  
Root Zone ◽  
Relative Yield ◽  
Single Layer ◽  
Nutrient Status ◽  
Growth And Yield ◽  
Balance Model ◽  
Relative Reduction ◽  
Wet Season ◽  
Annual Water

SummaryThe water use of clonal tea (Clone 6/8) in a line-source irrigation × nitrogen experiment in the Southern Highlands of Tanzania was monitored with a neutron probe during 1987 and 1988 to a depth of 3 m and 1989 to a depth of 5 m. The results for 1989 were used to calibrate a single layer water balance model which was then used to estimate water use for the preceding 1986, 1987 and 1988 dry seasons. In the model evapotranspiration was reduced linearly when the soil water deficit exceeded a critical value of 60 mm. The model predicted water use well for unirrigated, partially irrigated and fully irrigated treatments. Total extractable water was 330 to 350 mm in the 5.5 m deep root zone and estimated annual water use in 1988/89 ranged from 800 mm for unirrigated to 1200 mm for fully irrigated plots, of which about 400 mm was used in the wet season from December to April. Water use efficiencies were between 1 to 4 kg of made tea ha−1 mm−1, increasing with improving water and nutrient status. The slope (b) of the relation between the relative yield loss and the relative reduction in water use was very steep (b = 1.3) reflecting the sensitivity of shoot growth and yield of this clone to water stress.

No-tillage and dry ploughing compared with puddling for wet-season rice on an alluvial sandy clay–loam in eastern India

1990 ◽  
Vol 114 (1) ◽  
pp. 79-86 ◽  
Author(s):  
K. R. Mahata ◽  
H. S. Sen ◽  
S. K. Pradhan ◽  
L. N. Mandal
Keyword(s):  
Root Zone ◽  
Soil Strength ◽  
Dry Season ◽  
Growth And Yield ◽  
Root Weight ◽  
No Tillage ◽  
Clay Loam ◽  
Wet Season ◽  
Sandy Clay Loam ◽  
Sandy Clay

SUMMARYNo-tillage and dry ploughing were compared with puddling under identical cultivation conditions for their effect on growth and yield of wet-season rice. The experiment was conducted on an alluvial sandy clay–loam soil over 5 years (1978–82) at Cuttack, India. In the preceding dry season, each plot was split into two halves for growing dry-season crops, with and without tillage. Growth of rice seedlings without applying N to the seed bed was faster and more vigorous after puddling, as shown by greater shoot and root weight per hill and a higher shoot:root ratio, and remained so until maturity. This was reflected in earlier flowering and maturity, followed by greater grain and straw yields. These results are attributed to the ability of the roots to obtain more N from the puddled soil.Under high water table conditions, extractable and soluble N in the root zone were not much influenced by tillage treatments. Grain and straw yields after no-tillage were similar to those produced by dry ploughing but smaller than those produced by puddling, although the differences were not significant in some years.Soil strength measured at the end of the rice-growing season in 1980 and 1981 was significantly greater after continuous no-tillage. The decreasing trend in grain and straw yield and number of panicle-bearing tillers/m2 from 1980 onwards after continuous no-tillage, was associated with increasing soil strength. The results suggest that, where percolation losses of water and nutrients are small, puddling, which is capital intensive and detrimental to soil structure, could be replaced by notillage accompanied by suitable N and weed management. However, continuous no-tillage is not recommended for a soil with a lower clay content because the soil will gradually harden with time.

Characterizing water use by irrigated wheat at Griffith, New South Wales

Soil Research ◽  
1987 ◽  
Vol 25 (4) ◽  
pp. 499 ◽  
Author(s):  
WS Meyer ◽  
FX Dunin ◽  
RCG Smith ◽  
GSG Shell ◽  
NS White
Keyword(s):  
Water Use ◽  
Field Experiments ◽  
Root Zone ◽  
Soil Surface ◽  
Irrigation Scheduling ◽  
Balance Model ◽  
Wheat Crop ◽  
Water Tables ◽  
Irrigated Wheat ◽  
Upward Flux

Wheat is being grown increasingly in the irrigated areas of south-east Australia. Its profitability depends on high yields, which in turn, are highly dependent on accurate water management. This combination, together with the increasing need for greater water use efficiency to minimize accessions to rising water-tables, calls for effective irrigation scheduling. To achieve this, accurate estimates of crop water use and upward fluxes of water into the root zone from shallow water-tables are required. A weighing lysimeter, installed in 1984, measured hourly evaporation (Ea) from a wheat crop which enabled the accuracy of water use estimates to be assessed. Daily potential evaporation (Ep) was calculated from a combination equation previously calibrated over lucerne, while previously developed crop coefficients for wheat were used to convert Ep to estimated Ea. Daily Ea was the major component in a water balance model for irrigated wheat. The model was quite efficient (r2 = 0.911, but with a bias of -8.8%, which indicated that Ea values were generally underestimated. The underestimate was due primarily to the wind function used in the calculation of Ep, and alternative functions for both daily and hourly calculations were derived. The 1984 lysimeter data also showed that change in soil water content was accurately measured with the field-calibrated neutron probe. Comparisons of measured and estimated water use from field experiments in 1981 and 1982 indicated that upward flux from a water-table between 1 a5 and 2.1 m below the soil surface may be up to 30% of daily Ea. This upward flux will need to be taken into account if irrigation scheduling is to promote efficient use of irrigation water.

INFLUENCE OF GREENHOUSE SHADING AND DIFFERENT NUTRIENT MANAGEMENT PRACTICES ON ALLEVIATING HEAT STRESS, IMPROVING PLANT NUTRIENTS STATUS, FLOWERING GROWTH AND YIELD OF TOMATO

2020 ◽  
Vol 51 (4) ◽  
pp. 1001-1014
Author(s):  
Sulaiman & Sadiq
Keyword(s):  
Heat Stress ◽  
Management Practices ◽  
Nutrient Management ◽  
Block Design ◽  
Nutrient Status ◽  
Growth And Yield ◽  
Reproductive Growth ◽  
Positive Effects ◽  
Nutrition Programs ◽  
The Impact

The experiment was conducted in a greenhouse during 2017 and 2018 growing seasons to evaluate the impact of the shading and various nutrition programs on mitigating heat stress, reducing the use of chemical minerals, improving the reproductive growth and yield of tomato plant. Split-plot within Randomized Complete Block Design (RCBD) with three replications was conducted in this study. Shading factor was allocated in the main plots and the nutrition programs distributed randomly in the subplots. Results indicate that shading resulted in the decrease of daytime temperature by 5.7˚C as an average for both seasons; thus a significant increasing was found in leaf contents of macro nutrients (Nitrogen, Phosphorous, and Potassium), and micro nutrients (Iron, Zinc and Boron), except the Iron content in 2018 growing season. Furthermore, shading improved significantly the reproductive growth and tomato yield. Among the plant nutrition programs, the integrated nutrient management (INM) including the application of organic substances, bio inoculum of AMF and 50% of the recommended dose of chemical fertilizers; lead to the enhancement of nutrients content, reproductive characteristics and plant yield. Generally, combination of both shading and INM showed positive effects on plants nutrient status and persisting balance on tomato flowering growth and fruits yield.

scholarly journals High-Resolution Spatiotemporal Water Use Mapping of Surface and Direct-Root-Zone Drip-Irrigated Grapevines Using UAS-Based Thermal and Multispectral Remote Sensing

2021 ◽  
Vol 13 (5) ◽  
pp. 954
Author(s):  
Abhilash K. Chandel ◽  
Lav R. Khot ◽  
Behnaz Molaei ◽  
R. Troy Peters ◽  
Claudio O. Stöckle ◽  
...  
Keyword(s):  
High Resolution ◽  
Water Use ◽  
Root Zone ◽  
Lateral Roots ◽  
Irrigation Treatment ◽  
Crop Coefficient ◽  
Spatiotemporal Resolution ◽  
Site Specific ◽  
Canopy Transpiration ◽  
Irrigation Treatments

Site-specific irrigation management for perennial crops such as grape requires water use assessments at high spatiotemporal resolution. In this study, small unmanned-aerial-system (UAS)-based imaging was used with a modified mapping evapotranspiration at high resolution with internalized calibration (METRIC) energy balance model to map water use (UASM-ET approach) of a commercial, surface, and direct-root-zone (DRZ) drip-irrigated vineyard. Four irrigation treatments, 100%, 80%, 60%, and 40%, of commercial rate (CR) were also applied, with the CR estimated using soil moisture data and a non-stressed average crop coefficient of 0.5. Fourteen campaigns were conducted in the 2018 and 2019 seasons to collect multispectral (ground sampling distance (GSD): 7 cm/pixel) and thermal imaging (GSD: 13 cm/pixel) data. Six of those campaigns were near Landsat 7/8 satellite overpass of the field site. Weather inputs were obtained from a nearby WSU-AgWeatherNet station (1 km). First, UASM-ET estimates were compared to those derived from soil water balance (SWB) and conventional Landsat-METRIC (LM) approaches. Overall, UASM-ET (2.70 ± 1.03 mm day−1 [mean ± std. dev.]) was higher than SWB-ET (1.80 ± 0.98 mm day−1). However, both estimates had a significant linear correlation (r = 0.64–0.81, p < 0.01). For the days of satellite overpass, UASM-ET was statistically similar to LM-ET, with mean absolute normalized ET departures (ETd,MAN) of 4.30% and a mean r of 0.83 (p < 0.01). The study also extracted spatial canopy transpiration (UASM-T) maps by segmenting the soil background from the UASM-ET, which had strong correlation with the estimates derived by the standard basal crop coefficient approach (Td,MAN = 14%, r = 0.95, p < 0.01). The UASM-T maps were then used to quantify water use differences in the DRZ-irrigated grapevines. Canopy transpiration (T) was statistically significant among the irrigation treatments and was highest for grapevines irrigated at 100% or 80% of the CR, followed by 60% and 40% of the CR (p < 0.01). Reference T fraction (TrF) curves established from the UASM-T maps showed a notable effect of irrigation treatment rates. The total water use of grapevines estimated using interpolated TrF curves was highest for treatments of 100% (425 and 320 mm for the 2018 and 2019 seasons, respectively), followed by 80% (420 and 317 mm), 60% (391 and 318 mm), and 40% (370 and 304 mm) of the CR. Such estimates were within 5% to 11% of the SWB-based water use calculations. The UASM-T-estimated water use was not the same as the actual amount of water applied in the two seasons, probably because DRZ-irrigated vines might have developed deeper or lateral roots to fulfill water requirements outside the irrigated soil volume. Overall, results highlight the usefulness of high-resolution imagery toward site-specific water use management of grapevines.

scholarly journals Effect of Deficit Irrigation and Reduced N Fertilization on Plant Growth, Root Morphology and Water Use Efficiency of Tomato Grown in Soilless Culture

Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 228
Author(s):  
Ikram Ullah ◽  
Hanping Mao ◽  
Ghulam Rasool ◽  
Hongyan Gao ◽  
Qaiser Javed ◽  
...  
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Irrigation Water ◽  
N Fertilization ◽  
Water Levels ◽  
Growth And Yield ◽  
Root Surface Area ◽  
Irrigation Water Use Efficiency ◽  
Irrigation Water Use ◽  
Use Efficiency

This study was conducted to investigate the effects of various irrigation water (W) and nitrogen (N) levels on growth, root-shoot morphology, yield, and irrigation water use efficiency of greenhouse tomatoes in spring–summer and fall–winter. The experiment consisted of three irrigation water levels (W: 100% of crop evapotranspiration (ETc), 80%, and 60% of full irrigation) and three N application levels (N: 100%, 75%, and 50% of the standard nitrogen concentration in Hoagland’s solution treatments equivalent to 15, 11.25, 7.5 mM). All the growth parameters of tomato significantly decreased (p < 0.05) with the decrease in the amount of irrigation and nitrogen application. Results depicted that a slight decrease in irrigation and an increase in N supply improved average root diameter, total root length, and root surface area, while the interaction was observed non-significant at average diameter of roots. Compared to the control, W80 N100 was statistically non-significant in photosynthesis and stomatal conductance. The W80 N100 resulted in a yield decrease of 2.90% and 8.75% but increased irrigation water use efficiency (IWUE) by 21.40% and 14.06%. Among interactions, the reduction in a single factor at W80 N100 and W100 N75 compensated the growth and yield. Hence, W80 N100 was found to be optimal regarding yield and IWUE, with 80% of irrigation water and 15 mM of N fertilization for soilless tomato production in greenhouses.

Water use efficiency and fruit quality of table grape under alternate partial root-zone drip irrigation

2008 ◽  
Vol 95 (6) ◽  
pp. 659-668 ◽  
Author(s):  
Taisheng Du ◽  
Shaozhong Kang ◽  
Jianhua Zhang ◽  
Fusheng Li ◽  
Boyuan Yan
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Fruit Quality ◽  
Drip Irrigation ◽  
Root Zone ◽  
Table Grape ◽  
Use Efficiency

scholarly journals WATER USE EFFICIENCY, GROWTH AND YIELD OF WHEAT CULTIVATED UNDER COMPETITION WITH Setaria

2015 ◽  
Vol 33 (4) ◽  
pp. 679-687 ◽  
Author(s):  
M.Z. IHSAN ◽  
F.S. EL-NAKHLAWY ◽  
S.M. ISMAIL
Keyword(s):  
Drought Stress ◽  
Water Use Efficiency ◽  
Water Use ◽  
Harvest Index ◽  
Wheat Yield ◽  
Negative Association ◽  
Growth And Yield ◽  
Yield Losses ◽  
Wheat Production ◽  
Use Efficiency

ABSTRACT Understanding the critical period of weed competition is indispensable in the development of an effective weed management program in field crops. Current experiment was planned to evaluate the critical growth period ofSetaria and level of yield losses associated with delay in weeding in rain-fed drip irrigated wheat production system of Saudi Arabia. Field experiment was conducted to evaluate the effect of weeding interval (07-21, 14-28, 21-35, 28-42 and 35-49 days after sowing) and drought stress (75% and 50% of field capacity) on Setaria growth, wheat yield and water use efficiency. Season long weedy check and wellwatered (100% FC) plots were also maintained for comparison. Weeding interval and drought stress significantly (p ≤ 0.05) affected the growth and yield of Setaria and wheat. Drought stress from 75% to 50% FC resulted in reductions of 29-40% in Setaria height, 14-27% in Setaria density and 11-26% in Setaria dry biomass. All weeding intervals except 35-49 DAS significantly suppressedSetaria growth as compared with control. Delay in weeding increased weed-crop competition interval and reduced wheat yield and yield contributors. Therefore, the lowest yield of 1836 kg ha-1 was attained for weeding interval of 35-49 DAS at 50% FC. Water use efficiency and harvest index increased with decreasing FC levels but reduced with delay in weeding. Correlation analysis predicted negative association ofSetariadensity with wheat yield and yield contributors and the highest negative association was for harvest index (-0.913) and water use efficiency (-0.614). Early management of Setaria is imperative for successful wheat production otherwise yield losses are beyond economical limits.

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