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The recent research was performed to investigate the toxicity of As and Cd in suburban area of Sargodha, Punjab, Pakistan. Water, soil and forage samples were collected for this purpose in summer and winter season and analysis was done via wet digestion to determine the concentration of selected heavy metals. The mean concentration of As and Cd in water was found above the permissible maximum limit. Mean concentration of Cd in soil and forages was lower than the allowed limit whereas As which was higher than the PML in forages. So, continuous use of domestic wastewater for irrigation purpose should be avoided in order to secure the area from any hazard in near future.

Se cruzaron seis genotipos divergentes de sésamo (Sesamum indicum L.) utilizando un medio dialélico excluyendo cruces recíprocos, para estimar la heterosis, combinando la capacidad y la naturaleza de la acción de los genes para los rasgos estudiados bajo dos regímenes de riego. Los dos regímenes de riego fueron condiciones de riego normales con una cantidad de agua aplicada de 5952,38 m3/ha y condiciones de estrés hídrico con una cantidad de agua aplicada de 2976,19 m3/ha en la Estación de Investigación Agrícola de Etay-El-Baroud, gobernación de Behaira, Centro de Investigación Agrícola, Egipto durante 2019 temporada de verano. Se utilizó un diseño de bloques completos al azar con tres repeticiones para cada régimen de riego. La variación de genotipos y sus componentes de padres, cruces y padres versus cruces fue altamente significativa para todos los rasgos estudiados bajo ambos regímenes de riego y sus interacciones con el riego. La variación atribuible a la capacidad de combinación general y específica fue muy significativa para el rendimiento de semillas y los componentes del rendimiento en ambos regímenes de riego. Los padres L92 y L110 fueron los mejores combinadores para peso de semilla por planta y la mayoría de sus componentes bajo ambos regímenes de riego. La mejor combinación cruzada F1 fue L92 × L110 en capacidad de combinación específica y efectos heteróticos sobre padres medios y mejores bajo ambos regímenes de riego para el peso de semilla por planta y la mayoría de sus atributos. Se observó la preponderancia de la acción aditiva de genes en la herencia de los rasgos más estudiados, lo que se confirmó además por su importancia y el valor del grado medio de dominancia superior a la unidad. La heredabilidad en sentido estricto varió de 0,19 para el número de ramas por planta a 0,47 para el peso de 1000 semillas bajo riego normal, mientras que, en condiciones de estrés hídrico, varió de 0,14 para el número de ramas por planta a 0,42 para la longitud de la zona de fructificación. Los padres L95 y L93 bajo riego normal y L93 y L110 bajo condiciones de estrés hídrico portaban principalmente genes con efectos dominantes para el peso de semilla por planta, por el contrario, L92 y L110 bajo riego normal y L92 y L12 bajo condiciones de estrés hídrico portaban principalmente alelos recesivos para semilla peso por planta. Por lo tanto, los resultados se utilizarán para desarrollar un programa de mejoramiento de sésamo en la Estación de Investigación Agrícola de Etay-El-Baroud.

Climate change is an obvious threat to agriculture, food security and conservation of plant genetic resources. Potato is a globally important food. In Peru, there is high variability and diversity of wild and cultivated species, such that they are considered as one of the region’s most vulnerable to the impact of climate change. With these considerations, we report the results of an investigation in which a preliminary screening of the reaction to drought of 67 native potato morphotypes was conducted to verify for differences in morphological indicators of growth, development, and production of tubers in response to continuous irrigation (CI) and restricted irrigation (RI) treatments. In the course of this study, 21 irrigations were applied to plants by CI (every 1-2 days) and, in the same period, 7 irrigations were applied to plants by RI (every 5-6 days). Comparison of characteristics average in all the morphotypes with plants under CI and RI, indicated that RI did not show differences in height of plants, length of internodes, or leaf and terminal leaflet indexes, and that RI reduced the stem thickness and dry weight of foliage. In this study, we highlight the morphotypes whose plant characteristics present higher averages with respect to their clonal counterparts that were treated with CI. The positive relationship between the number and weight of tubers harvested, as well as the significant reduction of both components of low RI yield is confirmed. In addition, we also highlight the response of some morphotypes that present higher tuber yield under RI. The native morphotypes that were identified as tolerant (according their responses in the characteristics of their plants and yield of tubers under RI) are as follows: BGR 19 (“Rayhuana”); BGR 99 (“Yuracc ñahui hualash”); BGR 170 (“Yana utcush”); and BGR 238 (“Muru huayro”).

In the recent years, biochar has been used as an organic soil amendment. Therefore, this study was undertaken in April 2016 to July 2017 to examine the effect of different biochar addition (BA) rates and deficit irrigation (DI) on quality characteristics of cucumber under greenhouse conditions over two consecutive growing seasons. The BA treatments were B0 (0-ton ha-1), B1 (10-ton ha-1and B2 (20-ton ha-1), while the DI treatments were 1.0 (W1), 0.60 (W2) and 0.40 (W3) of the reference evapotranspiration (ET0). The results obtained elaborated that the combination of B2W1 gave the maximum values of fruit weight (g), fruit water content (%), fruit dry biomass (g) and pH in the both seasons. On the other hand, W2 and W3 increased significantly titratable acidity (TA %) and total soluble solid (TSS %). It was possible to conclude that BA with DI might be a novel approach to improve both crop yield and fruit quality.

Because of the food and industrial importance of tomato, it holds great significance, and is one of the most produced species using the hydroponic cultivation systems. The objective of this study was to evaluate the effects of different concentrations of nutrient solution on the production and quality of cherry tomatoes (Lycopersicon esculentum ‘Samambaia’) grown in a hydroponic system in protected conditions. The experiment was conducted in pots filled with coconut fiber substrate using a randomized complete block design with four replications and six plants per plot. Five concentrations of nutrients were evaluated (50, 75, 100, 125, and 150% of the standard nutrient solution); the solutions produced the following electrical conductivities: 1.8, 2.0, 2.6, 3.4, and 3.9 dS m-1, respectively. At 90 days after transplanting, the tomato fruits were harvested, at which time the production variables and post-harvest quality of mature fruits were determined. The best production and post-harvest quality indexes of cherry tomatoes (‘Samambaia’) were found when using 111% of the standard nutrient solution, corresponding to the concentrations of 9.44, 2.44, 2.22, 6.44, 4.11, 2.44, and 2.78 mmolc L-1, of NO3-, NH4+, P, K, Ca, Mg, and S, respectively; and 66.6, 55.5, 14.4, 1.89, 0.56, and 0.44 mmolc L-1, of Fe, B, Mn, Zn, Cu, and Mo, respectively. Nutrient solutions with electrical conductivity above 2.89 dS m-1 severely reduced the fruit yield of cherry tomatoes.

For centuries the oases of the Saoura continue to manage critical situations of drought and the hostility of the Algerian Sahara through the rational exploitation of water, a rare and precious source of traditional irrigation techniques have proved their efficiency. The use of new groundwater drainage systems of drilling, and the lack of effective management of the Foggaras, has made this system lose its value, deteriorate and let the palm groves disappear. More than 80% of these systems have been abandoned in recent years. With increasing urbanization, population growth, climate change and the uncontrolled proliferation of motor pumps, the level of the water table is lowered and the quality of the water is degraded. The foggaras have gradually been abandoned, which leads to the degradation of the gardens and the old oasis.

Vlhkost hlinité černozemní půdy na karbonátovém sprašovém substrátu byla měřena metodou TDR čidly Aqua-Tel-TDR (Automata, Inc., dnes McCrometer CONNECT). Čidla, obalená před osazením pastou z místní zeminy a vody, byla instalována vodorovně do předvrtaných otvorů. Systematická chyba způsobená nedokonale zaplněnými mezerami mezi čidlem a stěnou otvoru byla zmenšena terénní kalibrací. Tytéž mezery umožnily indikovat preferenční proudění v půdních makropórech, díky němuž byla reflektometrická měření citelně vyšší než analogické hodnoty před průsakovou epizodou a někdy i vyšší než pórovitost původní půdy. Je demonstrována jedna typická epizoda. Lze předpokládat, že čidla tohoto typu mohou být použita k semikvantitativnímu odhadu hustoty preferenčního toku, např. za pomoci modelů dvojného nebo vícenásobného pórovitého prostředí nebo teorie rozptylu hybnosti.

The exploration of ostriches aims at trading meat, feathers, leather and grease. The digestive system is intimately related to productivity, and the celiac artery is amongst the major vessels responsible for its nutrition. The artery´s origin and distribution was studied here. In 30 specimens, the left ischiatic artery was cannulated for the injection of a blood vessels marker solution and then fixed in formalin solution 10% via deep intramuscular, subcutaneous and intracavitary applications. We concluded that this artery originated from the descending aorta, its first branch is ventral and it headed for the right side sending branches to: esophagus, proventriculus, ventriculus, spleen, liver, gallbladder, pancreas, duodenum, ileum, left and right cecum.

This article studies the optimal solution of an irrigation problem. It consists in optimizing the planning of water used so by the water amount in the soil (trajectory) fulfils the cultivation water requirements. We characterize the optimal solution by applying the necessary conditions of optimality in the form of the Maximum Principle. We also compare the results obtained analytically and numerically. [ABSTRACT FROM AUTHOR]

Mustard (Sinapis alba L.), Argentine canola (Brassica napus L. cv. Westar), Polish canola (Brassica campestris L. cv. Tobin), pea (Pisum sativum L.), durum wheat (Triticum durum L. cv. Kyle) and soft wheat (Triticum aestivum L. cv. Fielder) were grown at Outlook, Saskatchewan, Canada, under irrigated and dryland conditions. Carbon isotope discrimination (Δ) and water-use efficiency (W), defined as grams of above ground dry matter produced per kilogram water used, were negatively correlated in the six field-grown crops. In irrigated plants Δ remained relatively constant (20-21‰) throughout the growing season. However, in dryland plants, ‰ declined in response to the progressive depletion of stored soil water (Polish canola, 20.2-18.8‰; mustard, 19.9-18.5‰; pea, 19.9-17.2‰; durum wheat, 19.7- 16.4‰; Argentine canola, 19.4-17.6‰; soft wheat, 19.0-17.4‰). Although there were genetic differences in Δ among the species, water availability was the major factor controlling Δ. [ABSTRACT FROM AUTHOR]

Two patients with renal hemorrhage treated by arterial embolization are reported. In one patient, one kidney was injured and the another had poor function. The other patient had one kidney. Although both patients had hematuria and underwent percutaneous nephrostomy, the bleeding location was not detected angiographically. Repeated embolization and irrigations through a nephrostomy catheter following each embolization arrested the bleeding. [ABSTRACT FROM AUTHOR]

An understanding of water and chemical transport through the soil iscrucial for the development of proper irrigation and nutrient management practices. Because of natural heterogeneity and variability of soils, results often cannot be extrapolated between sites and from laboratory to field. In this study, transport of bromide (Br-) was investigated in a silt loam soil under intermittent and continuous pondingconditions using 10 pairs of stations in a 0.40-ha field. Each station consisted of a double ring infiltrometer and three solution samplers installed at 30, 60, and 100 cm depths. A 3-cm pulse of KBr- with an average Br- concentration of 500 ppm was applied to each station. Upon depletion of the pulse, 8 cm of water was ponded in each infiltrometer. For the continuous ponding stations, water was added daily and infiltrated volume was recorded. For each intermittent treatment, the time between subsequent irrigations was equal to the time for complete 8 cm infiltration plus 7 d of redistribution time. Solution samples were collected from all samplers on a daily basis for 3 mo, and analyzed for bromide concentration in the lab. At 30-cm depth, the mean tracer velocities for intermittent and continuous ponding treatments were larger than piston flow velocities by factors of 2.05 and 1.57, respectively. Solute velocities decreased with depth for both treatments. Nutrient management models based on piston flow velocities mayoverestimate the mass of available nutrients to plants in the root zone. [ABSTRACT FROM AUTHOR]

Although several studies have tested leaching models on field-scale data, a comparable case study on heavy metal transport has not yet been undertaken. Data concerning heavy metal displacement after 29 yr of controlled wastewater irrigation were used to compare several simple modeling approaches to predict total and solution phase concentration profiles in the soil. Approaches employed comprise parallel soil column (PSC) models and the application of the convection dispersion equation at the field scale (CD). The PSC simulations were either realized by one-dimensional (1D) simulations at points in the field wheresoil properties had been determined experimentally (grid model; GM or by the Monte-Carlo (MC) method. Sorption was described with an extended Freundlich equation as a function of the spatially variable soilproperties organic C content and pH. The CD simulations were based on conventional sorption isotherms of mixed samples determined in laboratory batch experiments. Cadmium profiles predicted by the PSC models agree very well with measured profiles, while leaching of Zn was somewhat underestimated. Grid model and MC simulations yielded largely similar results if correlation of random variables was considered in the MC simulations. In the PSC simulations no parameters were fitted to the measured concentration profiles. Agreement between CD simulations and measured data could only be achieved by adjusting the dispersion length to a value in the upper range of values found in the literature. [ABSTRACT FROM AUTHOR]

This paper consists of two parts. In the first part, the significance of five major factors, including solar radiation, vapor pressure deficit, relative humidity, wind speed and air temperature, that control evaporation were evaluated comparatively at different time-scales using the data from Changines station in Switzerland. The comparative evaluation was made at hourly, daily, 10-day and monthly time-scales.It was found that the role of controlling variables in evaporation varied with the time-scale. The vapor pressure deficit was best correlated with pan evaporation at all time-scales, while the wind speed was least correlated with pan evaporation, especially when the time period was longer than a day. In the second part, four equations for calculating evaporation, including temperature-based methods, humidity-based methods, mass transfer methods and radiation-based methods, werecompared with pan evaporation. Of these four equations, the Penman equation, representing the mass transfer method, resulted in monthly evaporation values that agreed most closely with pan evaporation values. The Romanenko equation, representing the humidity method, also compared reasonably well with pan evaporation. The Turc equation, representing the radiation method, and the Thornthwaite equation, representing the temperature method, were found to underestimate evaporation significantly, especially for cold months. [ABSTRACT FROM AUTHOR]

The chemical inputs by rainfall, throughfall and stemflow were studied in a pine plantation located in Pierces Creek Forest, Canberra, Australia. Three treatments were included in the study: a control (C) and two fertilizer treatments. The first fertilizer treatment (F) involved two applications of mixed fertilizers at high rates, the second (IL) involved application of a complete liquid fertilizer with irrigation, so as to remove nutrient and water restrictions to growth. The application rates of nutrients were higher for IL than F. Net inputs of elements in throughfall and stemflow, obtained by subtracting the amounts in the rainfall, were compared for different treatments. For cations (the sum of Ca, Mg, Na and K), the treatment effect on leaching by throughfall and stemflow was IL > F > C; but the F to C differences were greater for throughfall than stemflow. The effects were almost entirely due to increases in concentration, rather than the amount of rainfall becoming throughfall or stemflow. The concentration of nitrogen (as NH4 or NO3) in throughfall or stemflow could be lower or higher than in rainfall, indicating net removal or leaching, respectively. Net removal occurred for most rainfall events for the control treatment, for a substantial number of events for treatment F, but for few events for treatment IL. The ammonium ionwas preferentially removed from throughfall, and nitrate from stemflow. Transfers of potassium and total nitrogen by litterfall, throughfall and stemflow were also studied. The proportions of potassium and nitrogen being transferred by these processes showed little difference between treatments; the overall values for potassium being 60% by throughfall, 4% by stemflow and 36% by litterfall. In contrast the transfer of nitrogen was dominated by litterfall (81%), with 18% by throughfall and 1% by stemflow. [ABSTRACT FROM AUTHOR]