بررسی اثر کودآبیاری جویچه ای بر کارایی مصرف کود و آب، عملکرد و اجزای عملکرد ذرت دانه ای

To evaluate the specialty water soluble fertilizer namely Ultrasol (09: 05: 33) for Sustainable Sugarcane Initiative (SSI) under sub-surface drip irrigation (SSDI), this study was conducted at Agricultural College and Research Institute, Madurai during 2013–14. The study was designed in RBD with three replications, with treatments as various methods of fertilizer application including, soil application and drip fertigation. Sugarcane seedlings (var Co 86032) raised from single bud chips were planted (dual row) in trenches opened at 1.8 m, 40 cm width and 30 cm depth with 1.29 lph were placed in the centre of the trenches. SSDI was scheduled once in 3 days at 100% PE and fertigation was given based on crop growth demand at weekly interval from 15 to 210 DAP. Drip fertigation of 100% RDF with Ultrosol, MAP and Urea (F7) resulted in significantly highest the fertilizer use efficiency (FUE) (390.1 kg ha−1 cane yield N+P2O5+K2O applied) and higher water use efficiency (WUE) (120.28kg ha−1 mm−1) in Sustainable Sugarcane Initiative (SSI).

This paper uses an advanced computable general equilibrium model coupled with biophysical data on land and water resources by Agro-ecological zone at a river basin level to examine: 1) the economy-wide consequences of improvement in water use efficiency (WUE) in irrigation in South Asia; 2) the extent to which enhanced WUE can increase food production and improve food security in South Asia; and 3) how WUE in irrigation alters demand for water and affects land use across South Asia. Given that the extent to which the economies of South Asia can actually improve water use efficiency in irrigation is uncertain, it tests four different levels of efficiency gains in irrigation: 10%, 20%, 30%, and 40%. It examines improvement in WUE under two alternative cost assumptions: 1) improvement in WUE is costless and 2) improvement in WUE needs additional investment. With a 10 percent improvement in WUE, the overall respective increases in food production during the time period 2008-2030 in India, Bangladesh and the rest of South Asia would be about $50.5 billion, $3.5 billion and $29.6 billion at 2007 constant prices. Improvement in WUE in irrigation reduces the rain-fed harvested areas and increases irrigated areas. A 10 percent improvement in WUE increases the areas of irrigated cropland by 6.1 million hectares, 296,000 hectares and 1.9 million hectares in India, Bangladesh and the rest of South Asia. When improvement in WUE is costless, the net present values of gains due to a 10 percent improvement in WUE (with a 3 percent social discount rate) are about $45.6 billion for India, $3.6 billion for Bangladesh, and $21.8 billion for rest of South Asia at 2007 constant prices for the time period of 2007-2030. Gains grow as the level of improvement in WUE increases. When improvement in WUE needs additional investments, welfare gains drop but gains in food production remain high.

Three diploid (Triticum boeoticum, AA; Aegilops speltoides, BB and Ae. tauschii, DD), two tetraploid (T. dicoccoides, AABB and T. dicoccon, AABB) and one hexaploid (T. vulgare, AABBDD) varieties of wheat, which are very important in the evolution of wheat were chosen in this study. A pot experiment was carried out on the wheat under different water and nutrient conditions (i) to understand the differences in biomass, yield, water use efficiency (WUE), and nutrient (N, P and K) use efficiency (uptake and utilization efficiency) among ploidies in the evolution of wheat; (ii) to clarify the effect of water and nutrient conditions on water and nutrient use efficiency; and (iii) to assess the relationship of water and nutrient use efficiency in the evolution of wheat. Our results showed that from diploid to tetraploid then to hexaploid during the evolution of wheat, both root biomass and above‐ground biomass increased initially and then decreased. Water consumption for transpiration decreased remarkably, correlating with the decline of the growth period, while grain yield, harvest index, WUE, N, P and K uptake efficiency, and N, P and K utilization efficiency increased significantly. Grain yield, harvest index and WUE decreased in the same order: T. vulgare > T. dicoccon > T. dicoccoides > Ae. tauschii > Ae. speltoides > T. boeoticum. Water stress significantly decreased root biomass, above‐ground biomass, yield, and water consumption for transpiration by 47–52%, but remarkably increased WUE. Increasing the nutrient supply increased wheat above‐ground biomass, grain yield, harvest index, water consumption for transpiration and WUE under different water levels, but reduced root biomass under drought conditions. Generally, water stress and low nutrient supply resulted in the lower nutrient uptake efficiency of wheat. However, water and nutrient application had no significant effects on nutrient utilization efficiency, suggesting that wheat nutrient utilization efficiency is mainly controlled by genotypes. Compared to the other two diploid wheats, Ae. squarrosa (DD) had significant higher WUE and nutrient utilization efficiency, indicating that the D genome may carry genes controlling high efficient utilization of water and nutrient. Significant relationships were found between WUE and N, P and K utilization efficiency.(Handling editor: Jin‐Zhong Cui)

Consumptive use of water data for wheat crop in Peshawar valley is needed to improve management practices, irrigation scheduling and water resources planning. The data are also needed to evaluate the moisture stress and fertilizer use especially due to scarcity of irrigation water during Rabi season. Therefore, a research study was initiated during 1977-78 at Agricultural University Farm Peshawar which continued for three (3) consecutive years in order to have reliable estimates. The experimental site was located on deep clay loam soil and belonged to Peshawar series. Three moisture stress levels of 50, 75 and 90% soil moisture depletion in the top 0— 30 cm soil depth and two fertilizer levels of 56-28— 34 and 168-84-34 (NPK) kg/ha were employed in 3 x 2 randomized complete block design with 4 replications. Improved and recommended wheat varieties were grown during the period of investigations. The results indicated that the amount of water used by the crop during growing season can be reduced without any significant reduction in yield. The average Consumptive use of water values for the three moisture stress levels were computed to be 477, 448 and 365 mm of water. The moisture stress yield functions data indicated that the optimum yield of wheat grain of 2349 Kg/ha was obtained when the crop was irrigated at 75% soil moisture depletion level under properly fertilized conditions. The water use efficiency was increased by 23% with the increase of moisture stress. The highest water use efficiency of 5.9 Kg/mm was obtained when the crop was irrigated at 90% soil moisture depletion.

Mutual physiological genetic mechanism of plant high water use efficiency and nutrition use efficiency

Based on a panel data from National Rural Fixed Point Survey (NRFP), this study explored the effects of information and communication technologies (ICTs) on the fertilizer and pesticide use efficiency of China's grain production and the mechanisms using stochastic frontier analysis (SFA) and two‐way fixed‐effects model with two‐stage least square (2SLS) estimation. The results show that the average fertilizer use efficiency (FE), pesticide use efficiency (PE) and comprehensive fertilizer and pesticide use efficiency (CFPE) of grain production were 0.286, 0.404, and 0.364 respectively during 2003–2011. It should be noted that the CFPE decreased by 48.39% during 2003–2011 and showed a descending trend in all regions. ICTs had significant positive effects on FE, PE, and CPFE which could be explained by providing farmers more sustainable knowledge and hence shifting farming practices from overusing fertilizer towards using farmyard manure as a substitute. ICTs' positive effects were more pronounced for farmers with higher‐level education and in central region. Additionally, ICTs had significant spillover effects, extending from users to nonusers within the villages. These results suggest that ICTs could be considered as an effective way to increase the fertilizer and pesticide use efficiency and promote the sustainable development of agriculture in China.

Ethiopia has possibly the greatest potential for potato production. But its contribution to food security is less due to poor agronomic techniques and other factors which require improving the ways of resources use. This experiment was conducted in Jimma University College of Agriculture and Veterinary Medicine greenhouse to study the effect of nitrogen rates and irrigation regimes on water and nitrogen use efficiency of selected potato varieties (Jalenie, Guassa and Degemegn), using three nitrogen rates (130, 110, 90 kg/ha), and three irrigation regimes [full irrigation (100%), 80% and 60% of full irrigation] on clay textured fine top soil filled to poly ethylene pot of 15 liter and 30 cm upper diameter. The experiment was 3 × 3 × 3 factorial with three replications laid down in a Randomized Complete Block Design. Interaction of variety and irrigation significantly affected water use efficiency (WUE). Jalenie variety recorded the highest WUE at 80% irrigation, but was on par with Guassa varieties at 100% irrigation. The lowest WUE was obtained from Degemegn variety at 100% irrigation even though there was no significant difference among the three irrigations. From the results, it can be concluded that irrigation regimes and variety were significantly affected water use efficiency of the potato varieties while the nitrogen rates and interaction between or among factors holding nitrogen combination were not influenced the water use efficiency of the potato varieties significantly. As this is output of greenhouse condition, open field experiment is suggested to be carried out to come up with conclusive results.

Understanding crop water requirements (CWR) in semi-arid region is essential for better irrigation practices, scheduling and efficient use of water since the water supply through rainfall is limited. This paper estimated the crop reference and actual evapotranspiration (Eto and ETc) respectively and the irrigation water requirement of rice (Oryza sativa L.) in Benin’s sub-basin of Niger River (BSBNR) of west Africa, using CROPWAT model. The long recorded climatic data, crop and soil data from 1942 to 2012 were computed with the Cropwat model which is based on the United Nations’ Food and Agriculture Organization (FAO) paper number 56 (FAO56). The Penman-Monteith method was used to estimate ETo. Crop coefficients (Kc) from the phenomenological stages of rice were applied to adjust and estimate the actual evapotranspiration ETc through a water balance of the irrigation water requirements (IR). The results showed the BSBNR annual reference evapotranspiration (ETo) was estimated at 1 967 mm. The lowest monthly value of ETo of 123 mm, was observed in August month, middle of the rainy season while the highest value 210 mm was observed in March within dry season. The crop evapotranspiration ETc and the crop irrigation requirements were estimated at 651 mm and 383 mm, respectively in rainy season and 920 mm and 1 148 mm, respectively within a dry season. Irrigation projects of these seasons can then be scheduled for water use efficiency based on these findings. Keywords: crop evapotranspiration, irrigation water requirement, rice, CROPWAT, model, Benin DOI: 10.3965/j.ijabe.20150802.1290

Effects of gravel–sand mulch, plastic mulch and ridge and furrow rainfall harvesting system combinations on water use efficiency, soil temperature and watermelon yield in a semi-arid Loess Plateau of northwestern China

Current knowledge on using 13C discrimination as an indirect measure of yield and water use efficiency (WUE) under different soil moisture conditions and soil fertility inputs in C4 crop species has considerable uncertainty. The objective of this study was to test for (i) the effect of selected soil water conservation measures and soil fertility inputs on sorghum yield, water use efficiency, and 13C discrimination, (ii) evaluate the relationship between various measures of water use efficiency and 13C discrimination, between sorghum yield and 13C discrimination; (iii) sorghum stem diameter and WUE and, the use of stem diameter and 13C discrimination as potential yield and WUE proxy. We implemented a field trial on-station for five seasons in the semi-arid areas of Upper Eastern Kenya. The experiment was designed in a randomized complete block design (RCBD) with three levels of nitrogen fertilization (120 kg ha−1, 60 kg ha−1, and 30 kg ha−1) application with four replications. The selected soil water conservation measures and soil fertility management were minimum tillage, mulching, tied ridging, and Managing Beneficial Interactions in Legume Intercrops (MBILI) along a control (no input). Water use efficiency was determined using carbon discrimination analysis and gravimetric technique. The leaves and post-harvest grain samples were analyzed for %N, %C, and δ13C on an Isotope Ratio Mass Spectrometer (IRMS). A clear and significant (p≤ 0.05) treatment effect was observed on the 13C isotopic discrimination and sorghum yield and growth attributes over the five seasons. The highest (4.85 Mg ha-1) grain yield was observed with minimum tillage with crop residue treatment. The δ13C values ranged from -13.14to -11.86‰for the sorghum grain. Treatments under minimum tillage with residue and tied ridges and the MBILI intercrop had significantly (p≤ 0.05) higher sorghum grain yield, WUE, stem diameter, chlorophyll content, and high δ13C values. The 13C discrimination was significantly (p≤ 0.05) associated with yield, WUE, stem diameter, and leaf chlorophyll. In the treatment with high N rate, the equation relating 13C discrimination to yield was Yield (Mg ha-1) = 1.4822δ13C + 20.879; R² = 0.3518. A significant positive relationship (R2 = 0.31) was observed between grain N fertilizer use efficiency and grain δ13C in sorghum harvested from plots with high N rate treatments. There was also a correlation (R2 = 0.341; p=0.001) between WUE and sorghum stem diameter. Based on these results, we conclude that grain 13C discrimination values at maturity and stem diameter are a potential complementary criterion for assessing sorghum yield performance and WUE under different soil moisture and nutrient availability conditions. Therefore, it can be deduced that minimum tillage with crop residue with a high fertilizer application rate (120N/ha) improves sorghum grain yield, WUE, and higher grain δ13C values. The high grain δ13C values observed with minimum tillage with crop residue over the five seasons indicate that plants suffered less water stress under minimum tillage with crop residue treatment. Therefore, grain δ13C discrimination and stem diameter can be used as water use efficiency proxy with C4 crops like sorghum.

Ecosystem water use efficiency (WUEe) is a key metric of the coupled carbon and water cycles. Understanding WUEe variations along the climate gradient (arid to humid) and across different vegetation ecosystems is crucial for assessing the impacts of climate variability on these ecosystems. Based on the Penman-Monteith-Leuning version 2 (PML-V2) dataset from a coupled diagnostic biophysical model, this study investigated the spatiotemporal variations and driving factors of WUEe under different aridity conditions and across vegetation types in China from 2001 to 2020. The results showed that the annual mean WUEe was 1.36 ± 0.07 g C kg−1 H2O in China, and humid regions had higher WUEe than other arid regions except for the extremely arid regions (the top level of aridity classification). Annual WUEe showed an increasing trend of 0.084 g C kg−1 H2O/10a in China, which mainly occurred in humid areas. The forest ecosystem had the highest WUEe (2.48 g C kg−1 H2O), followed by shrubland (2.11 g C kg−1 H2O) and cropland (1.99 g C kg−1 H2O) ecosystems. Leaf Area Index (LAI) and vapor pressure deficit (VPD) contributed the most to increases in WUEe, which accounted for areal proportions of 63.82% and 77.36% of China, and average relative contributions of 31.80% and 14.73%, respectively. In contrast, air temperature (TEM) contributed the most to WUEe decreases, with an areal proportion of 61.73% and an average relative contribution of 12.42%. Normalized Difference Vegetation Index (NDVI), precipitation (PRE) and downward short-wave radiation (SSRD) showed little differences in the proportions of land area where they either promoted and suppressed WUEe and their respective relative contributions were 16.99%, 14.32% and 8.61%.

<p><strong>Purpose:</strong> This study was aimed to quantify the effect of different variety, planting density, training system and canopy position on tree water and nitrogen use efficiencies in relation to mango fruit yield and size as well as soil fertility in a 5-year-old mango plantation of tropical Australia.</p><p><strong>Material and Methods:</strong> Soil (0-10 cm) and mango foliar samples were collected from a 5-year-old, factorial field experiment testing the effects of two mango varieties (Calypso vs Keitt), two planting densities (medium vs high), two training systems (single leader vs conventional) and two sampling canopy positions (north vs south) on foliar total carbon (TC, %), total nitrogen concentration (TN, %), and stable carbon (C) and nitrogen (N) isotope compositions (δ<sup>13</sup>C and δ<sup>15</sup>N) as well as the corresponding total C, total N and δ<sup>13</sup>C and δ<sup>15</sup>N in the surface soil of tropical Australia. In addition, mango fruit yields and sizes were determined. Soil and foliar total C and N as well as δ<sup>13</sup>C and δ<sup>15</sup>N were determined on mass spectrometers at Griffith University. Each of the above treatment was replicated 6 times for foliar samples and 3 times for soil samples.</p><p><strong>Results:</strong> There were significant genetic effect on foliar total N concentration (TN, %), tree water use efficiency (WUE) as reflected by foliar δ<sup>13</sup>C, N use efficiency (NUE) as indicated by foliar TN and δ<sup>15</sup>N, mango fruit yield and sizes in the 5-year-old mango plantation of tropical Australia. Overall, mango variety of Keitt had higher tree WUE and NUE as well as higher mango yield and greater fruit size, compared with those of mango variety of Calypso. There were also significant environmental influences on mango tree WUE and NUE as well as mango yield and fruit size. In particular, high planting density had higher tree NUE, and lower WUE as well as higher N loss, compared with those of medium planting density. High planting density treatment also had higher soil total N, compared with that of medium planting density treatment. The convention training system also had higher tree NUE and WUE, compared with the single leader training system. The northern side of tree canopy (sunny side) had lower fruit number, compared with the southern side (shady side) of tree canopy.</p><p><strong>Conclusion:</strong> There were significant genetic and environmental influences on tree WUE and NUE as well as mango fruit yield and sizes in the 5-year-old mango plantation, highlighting the significant and exciting opportunities to improve mango tree WUE and NUE as well as fruit yield and soil fertility with both genetic selection and site management regimes.</p>

The productivity of sandy soils is mostly limited by their low water-holding capacity and excessive deep percolation losses, which reduce the efficiency of water and fertiliser use by plants. The effect of a crosslinked-type polyacrylamide, ALCOSORB 400, on water-holding capacity of a sandy soil, siliceous sands, was studied under the laboratory and glasshouse conditions. Water-holding capacity of the soil exposed to 0.01 MPa increased by 23 and 95% by adding 0.03 and 0.07% of polyacrylamide to the soil, respectively. This indicated that the soil treated with polyacrylamide was able to store more water than untreated soil, thereby reducing the potential losses due to deep percolation in sandy soils. However, the polyacrylamide in the treated soil did not significantly increase the quantity of water released from the soil by increasing the pressure from 0.01 to 1.5 MPa. The results from the first glasshouse experiment demonstrated that the excess amount of water stored in the soil by polyacrylamide was available to plants and resulted in higher water use and grain production. Consequently, there was a 12 and 18 fold increase in water use efficiency of soybean plants grown in soils treated with 0.03 and 0.07% polyacrylamide, respectively. The results from the second glasshouse experiment demonstrated that increasing amounts of polyacrylamides in a sandy soil can extend the irrigation interval without any adverse effect on the grain yield of soybeans.

Water-yield relation and water use efficiency of cotton ( Gossypium hirsutum L.) and second crop corn ( Zea mays L.) in western Turkey

Evaluating global ecosystem water use efficiency response to drought based on multi-model analysis.