A field experiment was conducted at the Agronomy Department Farm, Faculty of Agriculture, Assiut University during 2015/2016 and 2016/2017 seasons to study the effect of preceding crop, rates and splitting of nitrogen fertilizer on bread wheat production and nitrogen use efficiency. The experiment was carried out in randomization complete block design (RCBD) using split-split plot arrangement with three replications. Cropping system (corn-clover-wheat and corn-fallow-wheat) were assigned in main-plots while nitrogen fertilizer rates (56.25, 75.00 and 93.75 kg N/fed) were allotted in sub-plots and splitting doses of nitrogen (two, three and four equal doses) were allocated in sub-sub plots. The obtained data showed that plant height, spike length, number of spikes/m2, number of grains/spike, weight of grains/spike, seed index, grain yield, straw yield and nitrogen use efficiency were significantly affected by cropping sequence in favor of planting wheat after clover (fahl berseem) in the two growing seasons except nitrogen use efficiency in the first season. Increasing nitrogen fertilizer rates resulted in significant increase in all previous traits except nitrogen use efficiency trait which was decreased by increasing nitrogen fertilizer rates in both seasons. Moreover, splitting nitrogen rates into four equal doses significantly increased all studied traits as compared to three or two equal splits in the two growing seasons. Also, all interactions had a significant effect on all studied traits in both seasons. The highest mean values of grain yield (27.47 and 28.22 ard/fed in the first and second seasons, respectively) were obtained from the sequence of corn-clover-wheat when received highest nitrogen rate (93.75 kg N/fed) which was applied at four equal doses.

During the last two decades, it was shown that some specific nutrients play an important role in growth, reproduction and immunity. Among of these nutrients, BC (β-carotene) is required not only for maintaining vitality of the tissues in the reproductive tract but also for keeping the body in good health in general. Also there is a possible role of β-carotene as protective nutrient against cancer has been reported. As well other studies reported that β-carotene protects against lung cancer and probably against stomach cancer and it may also be protective against cancers of ovary, cervix, breast and other cancers except the cancers of colon or rectum. Feed of sheep is mainly poor in vitamin A, simply because of deficient BC in roughages, cereal stubble wheat straw, stored alfalfa hay and barely grain. Although green forages are the major source of carotenoids including β-carotene (BC), but they are not available throughout the year. This means that BC should be taken from exogenous sources in order to cover the deficiency of vitamin A from one side and to fill the tissue vitamin A reserves from the other side. Therefore, the aim of this study was to investigate the long-term effect of BC on LBW, age at puberty, number and percentage of estrus coming post-puberty, types of estrous cycle following puberty and P4 and E2 profiles at puberty and pre-and post- puberty in Farafra ewe lambs. The study contained 48 ewe lambs with mean body weight 13.25 ± 0.43 kg and divided into two equal groups (24 per each), the first group was injected i.m. with arachis oil (peanut oil) and considered control for the other treated group because it can be metabolized easily in the body, the second group was injected i.m. 0.1 mg/kg by BC loaded on arachis oil 2 times a week for 4 months starting from weaning period to age at puberty. Beside detection of estrus by a ram, P4 value was taken as a marker in determining age at puberty. Olive oil can not be used for long time because of its destruction of the tissues. All ewe lambs were fed maintenance ration and housed in semi-open pens under Upper-Egypt environment conditions, El-Minia Governorate. P4 Blood samples (10 ml/animal) were withdrawn from 6 animals per each group (control and treatment) by jugular vein puncture into tubes without anticoagulant.After clotting blood samples were centrifuged at 3,000×g for 10 min to separate the sera, which was stored at −20°C until P4 and E2 assay. Both BC and vit. A were assayed by colorimetric method.

During the last two decades, it was shown that some specific nutrients play an important role in growth, reproduction and immunity. Among of these nutrients, BC (β-carotene) is required not only for maintaining vitality of the tissues in the reproductive tract but also for keeping the body in good health in general. Also there is a possible role of β-carotene as protective nutrient against cancer has been reported. As well other studies reported that β-carotene protects against lung cancer and probably against stomach cancer and it may also be protective against cancers of ovary, cervix, breast and other cancers except the cancers of colon or rectum. Feed of sheep is mainly poor in vitamin A, simply because of deficient BC in roughages, cereal stubble wheat straw, stored alfalfa hay and barely grain. Although green forages are the major source of carotenoids including β-carotene (BC), but they are not available throughout the year. This means that BC should be taken from exogenous sources in order to cover the deficiency of vitamin A from one side and to fill the tissue vitamin A reserves from the other side. Therefore, the aim of this study was to investigate the long-term effect of BC on LBW, age at puberty, number and percentage of estrus coming post-puberty, types of estrous cycle following puberty and P4 and E2 profiles at puberty and pre-and post- puberty in Farafra ewe lambs. The study contained 48 ewe lambs with mean body weight 13.25 ± 0.43 kg and divided into two equal groups (24 per each), the first group was injected i.m. with arachis oil (peanut oil) and considered control for the other treated group because it can be metabolized easily in the body, the second group was injected i.m. 0.1 mg/kg by BC loaded on arachis oil 2 times a week for 4 months starting from weaning period to age at puberty. Beside detection of estrus by a ram, P4 value was taken as a marker in determining age at puberty. Olive oil can not be used for long time because of its destruction of the tissues. All ewe lambs were fed maintenance ration and housed in semi-open pens under Upper-Egypt environment conditions, El-Minia Governorate. P4 Blood samples (10 ml/animal) were withdrawn from 6 animals per each group (control and treatment) by jugular vein puncture into tubes without anticoagulant.After clotting blood samples were centrifuged at 3,000×g for 10 min to separate the sera, which was stored at −20°C until P4 and E2 assay. Both BC and vit. A were assayed by colorimetric method.

The aim of this study was to assess live body weight (LBW), percentages of total body fluids (TBF), extracellular fluids (ECF), intracellular fluids (ICF), plasma volume (PV), and concentrations of aldosterone (ALD), sodium (Na) and potassium (K) in dry, early and late pregnant ewes in summer (July-August) and winter (FebruaryMarch). A total of adult healthy 48 ewes with different physiological statuses (8 dry ewes, 8 early pregnant ewes at 22-35 d of pregnancy, and late pregnant ewes at 144-145 d of pregnancy) were chosen by random way and housed in semi-open pens under the normal environmental conditions, Mallawi Sheep Farm ElMinia Governorate, Upper Egypt. TBW was determined by injecting j.v. 0.5 ml Urea solution/kg LBW, ECF was determined by injecting j.v. 0.25 ml sodium Thiosianate solution (5%) /kg LBW, PV was determined by injecting j.v. Evan's blue solution (0.5%) 0.1 ml/kg LBW, and ICF was calculated by subtract TBW from ECF. Before feed intake, blood samples were collected (6:00 a.m.) from all ewes via j.v. puncture for plasma aldosterone, Na and K determination. Results of this study indicate that LBW and Na concentration of dry and pregnant ewes were greater (P0.05) in summer than winter. K concentration in dry and early pregnancy was greater (P0.05) in winter than summer, but it was greater (P0.05) in late pregnancy in summer than winter. K concentration had a negative correlation with TBF, ICF and PV. Ald. concentrations and PV % in dry and pregnant ewes were greater in winter than summer. TBF and ECF percentages in dry ewes were similar in summer and winter, while they were (P0.05) greater in early and late pregnancy in summer than winter. ICF % in the dry ewes was (P0.05) greater in winter than summer, while the ICF % in early and late pregnancy was similar of both summer and winter. In conclusion, LBW of dry and pregnant ewes increased with increasing TBF % and Na concentration in summer, Ald. concentrations of dry and pregnant ewes increased with increasing Na and K concentrations and PV % in winter. K concentration had negative correlations with TBF, ICF and PV compartments. These results can be used to maintain body fluids and plasma volume responsible for the optimal cellular functions in sheep, particularly in summer.

The aim of this study was to assess live body weight (LBW), percentages of total body fluids (TBF), extracellular fluids (ECF), intracellular fluids (ICF), plasma volume (PV), and concentrations of aldosterone (ALD), sodium (Na) and potassium (K) in dry, early and late pregnant ewes in summer (July-August) and winter (FebruaryMarch). A total of adult healthy 48 ewes with different physiological statuses (8 dry ewes, 8 early pregnant ewes at 22-35 d of pregnancy, and late pregnant ewes at 144-145 d of pregnancy) were chosen by random way and housed in semi-open pens under the normal environmental conditions, Mallawi Sheep Farm ElMinia Governorate, Upper Egypt. TBW was determined by injecting j.v. 0.5 ml Urea solution/kg LBW, ECF was determined by injecting j.v. 0.25 ml sodium Thiosianate solution (5%) /kg LBW, PV was determined by injecting j.v. Evan's blue solution (0.5%) 0.1 ml/kg LBW, and ICF was calculated by subtract TBW from ECF. Before feed intake, blood samples were collected (6:00 a.m.) from all ewes via j.v. puncture for plasma aldosterone, Na and K determination. Results of this study indicate that LBW and Na concentration of dry and pregnant ewes were greater (P0.05) in summer than winter. K concentration in dry and early pregnancy was greater (P0.05) in winter than summer, but it was greater (P0.05) in late pregnancy in summer than winter. K concentration had a negative correlation with TBF, ICF and PV. Ald. concentrations and PV % in dry and pregnant ewes were greater in winter than summer. TBF and ECF percentages in dry ewes were similar in summer and winter, while they were (P0.05) greater in early and late pregnancy in summer than winter. ICF % in the dry ewes was (P0.05) greater in winter than summer, while the ICF % in early and late pregnancy was similar of both summer and winter. In conclusion, LBW of dry and pregnant ewes increased with increasing TBF % and Na concentration in summer, Ald. concentrations of dry and pregnant ewes increased with increasing Na and K concentrations and PV % in winter. K concentration had negative correlations with TBF, ICF and PV compartments. These results can be used to maintain body fluids and plasma volume responsible for the optimal cellular functions in sheep, particularly in summer.

Nowadays, using sewage wastewaters in the irrigated agriculture is commune creating hazardous environment impacts. Assessment of these negative effects is vital issue to prevent heavy metals to be introduced in the food chain. Field and laboratory studies were conducted at Arab-El-Madabegh village, Assiut Governorate, Egypt, in order to evaluate the heavy metals concentrations in the edible parts of lettuce and spinach plants which irrigated with sewage water (SW). The obtained results indicated that, the soils of the studied site were contaminated by heavy metals. Zinc, Cu, Pb, Cd and Ni concentrations in the edible portions of the studied vegetables plants ranged between 75- 110, 15 - 17, 2 - 5, 1.0 -3.5 and 1.0 -2.5 mg kg−1, respectively. The obtained results showed that the concentrations of Zn, Pb, Cd and Ni in the edible parts of the studied plants were higher than the permissible limit levels but those of Cu were within the safe limit levels. It is worthy to mention that the irrigated edible vegetable crops with SW should be avoided. This study highlights the potential hazard for human health due to the uptake of high concentrations of heavy metals especially Zn, Ni, Cd and Pb by the studied vegetable crops.

Halophytes have several advantages to be more effective in metal phytoextraction. Little is known about the Cd-phytoextraction potential of Atriplex lentiformis under different levels of Cd. Seven levels of Cd (0, 40, 80, 120, 160, 200, and 240 mg per kg of soil) were added to A. lentiformis plants grown on pots filled with 5 kg of sandy loam soil. A. lentiformis plants achieve different defense mechanisms to meet the high concentration of Cd in the soil and plant. These mechanisms include reducing the number and area of leaves, minimizing chlorophyll synthesis, and enhancing synthesizing of oxalic acid, phenols, and proline. The critical point of Cd was 9.35 and 183 mg kg−1 for available soil Cd and leaves concentrations, respectively. The maximum level of Cd displayed a 66% decrease in the chlorophyll content of the leaves. On the other hand, the oxalic acid, phenols, and proline in the leaves were increased significantly by 129, 100, and 200% when Cd increased from 0 to 240 mg. The tested plant removed 3.6% of the total soil Cd under the low Cd concentration (40 mg) but under the high level of Cd (240 mg), it only removed a negligible amount of soil Cd (0.74%). The current study confirmed that A. lentiformis plants lost the ability to cleanup Cd from contaminated soil under the high levels of contamination due to the high reduction in the production of dry matter

Halophytes have several advantages to be more effective in metal phytoextraction. Little is known about the Cd-phytoextraction potential of Atriplex lentiformis under different levels of Cd. Seven levels of Cd (0, 40, 80, 120, 160, 200, and 240 mg per kg of soil) were added to A. lentiformis plants grown on pots filled with 5 kg of sandy loam soil. A. lentiformis plants achieve different defense mechanisms to meet the high concentration of Cd in the soil and plant. These mechanisms include reducing the number and area of leaves, minimizing chlorophyll synthesis, and enhancing synthesizing of oxalic acid, phenols, and proline. The critical point of Cd was 9.35 and 183 mg kg−1 for available soil Cd and leaves concentrations, respectively. The maximum level of Cd displayed a 66% decrease in the chlorophyll content of the leaves. On the other hand, the oxalic acid, phenols, and proline in the leaves were increased significantly by 129, 100, and 200% when Cd increased from 0 to 240 mg. The tested plant removed 3.6% of the total soil Cd under the low Cd concentration (40 mg) but under the high level of Cd (240 mg), it only removed a negligible amount of soil Cd (0.74%). The current study confirmed that A. lentiformis plants lost the ability to cleanup Cd from contaminated soil under the high levels of contamination due to the high reduction in the production of dry matter

Little is known about the efficiency of biochar in the safety of food production in arid and semiarid contaminated soils. A field experiment in the semiarid region of Upper Egypt was conducted to explore heavy metals uptake by zucchini (Cucurbita pepo L) plants as affected by the application of cow manure biochar (CMB). Three rates of CMB were added, i. e., 0, 4, and 8 tonnes ha−1 . The roots and shoots of zucchini plants stored 75 and 78% of Zn and Cu, respectively, while 25 and 22% were transported to the edible portions. On the other hand, the roots and shoots of zucchini plants stored more than 99% of Pb and Cd, while less than 1% was transported to the edible portions. Cow manure biochar (CMB) minimized the values of bioaccumulation factor (BAC) for Zn, Cd, and Ni by 5.6, 21.9, and 27.9%, respectively, while these reductions in the case of translocation factor (TF) were 4.9, 7.5, 23, and 5.9%. Cow manure biochar at a rate of 4 tonnes ha−1 reduced the availability of Zn, Cu, Pb, Cd, and Ni by 13.3, 8.3, 13.8, 9.1, and 3.6%, respectively, compared to the control treatment. Cow manure biochar at a rate of 8 tonnes minimized Zn, Cu, Pb, Cd, and Ni concentrations in the edible parts of zucchini plants by 10, 17, 66, 20, and 26%, respectively, in comparison with the untreated soil. Biochar reduced the heavy metals bioavailability, moreover; biochar minimized the soil-root transfer and the rootshoot of toxic metals. It is recommended to add cow manure biochar to zucchini plants to reduce the accumulating of hazard metals in the edible tissues.

Abstract Recently, the residues of some common and widely used herbicides (acetochlor, bispyribac-sodium, bentazon, bensulfuronmethyl, halosulfuron-methyl, and quinclorac) were detected in the surface water, soil, sediments, and fish tissues as the agricultural drainage problems. In this study, juveniles of Nile tilapia Oreochromis niloticus were exposed to sub-lethal concentrations of these herbicides as 2.625, 0.800, 36.00, 2.50, 1.275, and 11.250 mg/l for acetochlor, bispyribac-sodium, bentazon, bensulfuronmethyl, halosulfuron-methyl, and quinclorac respectively for 96 h. Some hemato-biochemical parameters were evaluated. In comparison with the control group, sub-lethal concentrations of all tested herbicides induced alterations in the shape of erythrocytes. Also, in all tested herbicides, hematological parameters of exposed fish exhibited a significant decrease in red blood cell count except bentazon. However, all tested herbicides showed an insignificant reduction in mean corpuscular hemoglobin concentration and total white blood cells except bensulfuron-methyl. For biochemical parameters, most tested herbicides induced a significant increase in levels of cholesterol, albumin, globulin, albumin/globulin ratio, activity of alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total plasma protein (only with acetochlor), urea, and creatinine (except bentazon and halosulfuron-methyl that exhibited non-significant decrease in creatinine level) compared with the control. In conclusion, the fish blood profiles can be used as good biomarkers for laboratory study to assess the toxicity of the tested rice herbicides at a sub-acute level especially acetochlor on O. niloticus.