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Unlike edaphic factors, it is difficult to control climatic conditions and their changes that affect plant growth and development. To deal with such posture, farmers have to cultivate their crops at the right time. From this point, over two–year of 2014 and 2015, a field experiment was performed at El-Nubaria region, El-Behaira Governorate, Egypt, to assess the response of sunflower to different combinations between sowing dates (early, mid and delayed) and ascorbic acid treatments (with ascorbic acid and without ascorbic acid). Ascorbic acid was sprayed at 30, 40 and 50 days after sowing. The results showed that sowing sunflower in mid sowing (May 21) achieved the highest values of cumulative heat units utilization efficiency as well as all growth and yield traits, while the lowest values were recorded under the delayed sowing date (June 21). Application of ascorbic acid was effective for promoting growth and yield traits under all studied sowing dates. Ascorbic acid achieved 11.6, 10.1, 10.7 and 12.9% increases under early sowing, and 9.5, 6.6, 8.6 and 10.3% increases under delayed sowing in head diameter, seed weight plant−1, seed yield and oil yield, respectively. Comparing to mid sowing × without ascorbic acid, application of ascorbic acid alleviated seed yield losses associated early sowing from 15.7–6.6% and from 23.0–16.4% with delayed one. In conclusion, for remediating the thermal stressful impacts of early or late sowing of sunflower, farmers are advised to treat crop plants with ascorbic acid to avoid yield losses.

It has already been well established that long exposure to low doses of pesticides is linked to consumer risks. So, this study purposed to investigate the amounts of pesticide residues and potential health risks associated with them. The risk assessment was determined by two methods: 1. Pesticide toxicity index (PTI) depending on the maximum residue limit (MRL) to calculate the hazard quotient (HQ); 2. Health risk assessment (HR) using acceptable daily intake (ADI) and estimated daily intake (EDI) to calculate the health index (HI). Pesticide residues were estimated in 176 samples of the most popularly consumed vegetables collected from major retailers and markets in Dakahlia, Egypt (during 2018). There were 111 samples contaminated with pesticide residues (63.1%), of which 29 samples (16.48%) were higher than the maximum residue limits (MRL). Residues of 23 compounds were found in the analyzed samples, of which chlorpyrifos was the most frequent in 33 samples (18.75%); while cypermethrin was the lowest (detected in one sample). According to WHO toxicity classification, 12 of the detected pesticides were moderately hazardous (class II), seven pesticides belonged to class III (slightly hazardous), three compounds were found in class U (unlikely to pose an acute hazard with normal use), while carbofuran is a highly toxic compound (class Ib). Also, the obtained data revealed that, the HI’s for the individual pesticides ranged from 0.0018 to 64.0% of ADI indicates no risk of adverse effects following exposure to the individual pesticides. The cumulative exposure amounts (PTI values) ranged from 1.58 in snake cucumber to 128.44 in potato tubers, indicating that, the combined risk index of pesticide residues was a significant health risk for consumers according to the individual risk index. It can be concluded that there is a need for strict regulation and regular monitoring of pesticide residues in foodstuff for consumers’ health protection.

Globally, rationalizing and converting each drop of irrigation water into food is a crucial act in agricultural production, particularly with climatic change concerns. Thus, the current study seeks to find an integral practice between irrigation pattern and weed control for saving the irrigation water in peanut fields with improving the nutritional value of the seeds. In sandy loam soil, under two irrigation regimes (75 and 100% of crop evapotranspiration—ETc75 and ETc100, respectively), the responses of peanut pod yield and quality (seed oil, N, P, and K contents) and water use efficiency to six weed control treatments (bentazon, clethodim, bentazon + hoeing once,clethodim + hoeing once, hoeing twice and unweeded) were evaluated. The obtained data of 2016 and 2017 seasons illustrated that whether using ETc75 or ETc100, hoeing twice showed the highest efficiency of weed control in peanut. Reduction in yield was diminished from 15.1–16.9% in unweeded plots to 9.0–9.7% in weeded ones. Controlling weeds led to a decrease in their efficiency for exploiting the applied water. That decrease amounted to 64.4 and 64.3% reductions with ETc100 as well as 66.9 and 64.4% reductions with ETc75 in the 1st and 2nd seasons, respectively. Peanut plants consumed less water under ETc75 than ETc100 to produce one kilogram of pods by about 17.9% in weeded plots (mean of applied weeded treatments) as well as 10.1% in weedy conditions. Also, ETc75 plus weeded practices raised the benefit/cost by 52.3% compared to unweeded one. In conclusion, the interactional impact of irrigation and weed control proved that peanut plants can be irrigated as much as 75% of evapotranspiration under water shortage conditions with hoeing twice or herbicide use. Selecting the appropriate weed control practice is a vital act for water saving and keeping productivity, quality and returns of peanut cultivation in arid regions.

Background The objective of this work is to identify the most proper herbicidal treatment on sugar beet to compare different single weed control herbicide doses on sugar beet traits and associated weeds as well as yield and quality under sandy soil conditions. Therefore, two field experiments were conducted during the winter seasons of 2017/2018 and 2018/2019 at the Experimental Farm of the National Research Centre, El-Beheira Governorate. Tigro at 1.0 and 0.750 l fed−1, Betasana-Trio at 0.675 and at 0.9 l fed−1, Select Super at 0.5 and 0.375 l fed−1 and Betanal MaxxPro at 0.5 l fed−1 besides the unweeded and hand weeded twice were used. Results The results showed that the herbicides Betasana-Trio at 0.9 l fed−1, Tigro at 1.0 l fed−1 and Betasana-Trio at 0.675 l fed−1 when sprayed twice could effectively and/or completely eliminate the broadleaved weeds associated with sugar beet plants. Moreover, the results indicated and confirmed that Tigro and Betasana-Trio herbicides are effective in controlling broadleaved weeds. Similar tendency was recorded for the narrow-leaved weeds, where Select Super or Betanal MaxxPro at 0.5 l fed−1 as well as Select Super at 0.375 l fed−1 could completely eliminate or minimize the narrow-leaved weeds associated with sugar beet plants. The greatest significant root length, root diameters and root yield plant−1 were recorded when hand weeding twice followed by Betanal MaxxPro at 0.5 l fed−1 without significant differences. Gross sugar % ranged between 12.08 and 15 .7% and extractable sugar % ranged between 8.97 and 13.8% for Betasana-Trio at 0.09 l fed−1 and Betanal MaxxPro at 0.5 l fed−1. Conclusion Betanal MaxxPro gave the highest values of root and biological yield ton fed−1. Betanal MaxxPro followed by hand weeding treatment twice resulted in the greatest sugar yield fed−1. The highest sugar yield resulted from the herbicidal treatment with Betanal MaxxPro or Tigro at 1.0 l fed−1, which gave the greatest gross and extractable sugar yield fed−1 and exceeded the hand weeding treatment by 10.4 and 7.8%.

Maximizing the utilization of water unit is of paramount importance in arid zones and worldwide. This is even more significant when plants are subjected to both thermal and water stress. Hence, a two-year (2014 and 2015 seasons) field trial was carried out to study the effect of three sowing dates (April 21, May 21, and June 21); two irrigation levels (I100 and I85) and two ascorbic acid rates, ASA (0 and 450 mg L−1), on physiological and biochemical traits, productivity and water use efficiency (WUE) of sunflower. Results showed that subjecting sunflower plants to water deficit under any sowing date caused decreases in chlorophyll, carotenoids, oil% and seed yield and an increase in proline content. As averages of the two seasons, ASA treated plants caused increases in seed yield amounted to 11.7%, 10.6% and 8.4% with I100 and 5.1%, 14.4% and 7.7% with I85 compared to non-treated plants sown in April, May and June, respectively. In ASA treated plots, WUE values of sowing in April x I100 or sowing in June x I85 in 2014 and sowing in May x I85 in 2015 were as similar as that of conventional practice (sowing in May x I100 × 0 mg L−1 ASA). Accordingly, results clarify that ASA can be used successfully in sunflower management programs, particularly under abiotic stresses e.g. unfavorable heat and drought.

Due to the ability of weeds to deplete nutrients from the soil, crop plants become subjected to a complex of abiotic and biotic stresses. Thus, the interactive effects between one of the most important micronutrients, i.e., zinc (Zn) and some herbicides on weeds, rice yield and nutrient uptake were investigated. The experiment was carried out in a randomized complete block design in factorial arrangement using three replicates. Ten combinations of two Zn levels (without Zn, Zn−, and with Zn, Zn+) as well as four herbicides (halosulfuron–methyl, bentazon, azimsulfuron, pyrazosoulfuron–ethyl), and unweeded treatment were investigated. Findings clarified that application of halosulfuron–methyl herbicide whether with Zn− or Zn+ were the effective combinations for decreasing weed biomass. Halosulfuron–methyl and pyrazosoulfuron–ethyl had similar impact either with Zn− or with Zn+ resulted in minimum values of K uptake by weeds. The increases in grain yield ha−1 due to the application of halosulfuron–methyl, pyrazosoulfuron, azimsulfuron, and bentazon reached 13.4, 15.9, 21.3, and 24.8%, respectively, under Zn+ greater than Zn−. Halosulfuron–methyl x Zn+ was the promising interaction treatment for increasing P, K, and Zn uptakes by rice. Correlation coefficient showed that fertile panicle number, fertile grain number, rice N and K uptakes, weed biomass, and weed P uptake were the most closely associated traits with grain yield. Our study proved that there is a positive correlation between Zn and the applied herbicides in rice. Zn application alleviated the herbicidal pressure (abiotic stress) and decreased weed harmful impacts (biotic stress) on rice plants. Thus, it should be focused on the complementary effect between Zn and applied herbicides in breeding programs for generating new rice genotypes which are efficient in Zn utilization and tolerant to herbicides.

The abundance of broad-leaved weeds in peanut fields represents the handicap in weed management programs, since limited specific herbicides can be recommended to control them. Moreover, the physio-biochemical constituents and nutritional status in peanut plants as affected by available herbicides, i.e., bentazone under water stress conditions are not well known. Therefore, field trials were conducted during the growing seasons in 2016 and 2017 to investigate the interactional impact of irrigation levels (I50, I75 and I100, representing irrigation by 50%, 75% and 100% of crop evapotranspiration, respectively) and weed control practices (bentazone, bentazone+hoeing once, hoeing twice and weedy check as control) on dominant broad-leaved weeds as well as peanut physiological and agronomic traits. Result indicated that the efficiency of weed control for each weeded treatment under I50 significantly equaled with its counterpart under I75 or I100. Bentazone+hoeing once diminished weed biomass by 89.3% and enhanced chlorophyll content of peanut plants by 51.2%. Bentazone relatively caused a reduction in carotenoides. Hoeing twice and bentazone+hoeing once under I100 in both growing seasons as well as hoeing twice under I75 in 2017 were the superior combinations for boosting pod yield of peanut plants. Treatment of bentazone+hoeing once and I75 recorded the lowest reduction in N utilization percentage and the highest increase in potassium utilization percentage of peanut plants. Eliminating weeds enhanced water use efficiency by 37.8%, 49.6% and 34.7% under I50, I75 and I100, respectively. In conclusion, peanut seems to be tolerant to bentazone at moderate water supply, thus it can be safely used in controlling the associated broad-leaved weeds.

This study was conducted to evaluate the bioherbicidal properties of orange peelsagainst canary grass and cheeseweed mallow and the response of common bean plants.Two successive pot experiments were conducted with twelve treatments. The first fourtreatments were applied by incorporating of orange peels powder with the soil surface atsuccessive rates (10, 20, 30 and 40 g/pot) one week pre-sowing of common bean. Inthe other corresponding four treatments, the orange peels powder was incorporated withthe soil surface at the same rates but directly at the same time with sowing of commonbean seeds. Additionally, four untreated control treatments were applied for comparison.The recorded results revealed the inhibitory allelopathic effects of orange peels powderon both weeds with direct relationship between the orange peels rate and it's inhibitoryeffects. However, the pre-sowing treatments were more effective than the others whichapplied at the time of sowing. Orange peels at 40g/pot at one week pre-sowing gave thehighest inhibitory effect on both weeds. This superior treatment subsequently recordedthe highest growth parameters and yield traits of common bean. Estimated phenoliccompounds, flavonoids and essential oils in orange peels may be responsible for thisinhibitory effect.

Pesticide labels are the principal contact between the manufacturer and the end-user of the product as they convey essential use recommendations and safety information. So, this study aimed to assess the understanding level of pesticide labels, their field application practices, and observance of safety procedures among farmers, pesticide retailers, and applicators at Dakahlia Governorate, Egypt. The data revealed that, the majority of participantshad limited formal education(44.7%),illiterate (15.3%) or did not receive anytraining or technical backingin the safety of pesticides.Insecticides were the highest used (44.8%) followed by herbicides (27.6%) and fungicides (13.8%).Moderately hazardous compounds were the most frequently in the study area and Chlorpyrifos was the highest used compound by subjects (85%) followed by Lambda-cyhalothrin (71%) then glyphosate (herbicide) (64%).When participants bought pesticides, their choice was mostly based on their experience, the type of pests, effectiveness, recommendations taken from other people, and inexpensiveness.Data indicated also that, pesticide retailers had a crucial role in the spreading of pesticideinformationamong end-users.Our results revealed that, there is a strong correlation between workers’ education level and awareness about safety precautions and understanding the instructions of pesticide labels. The awareness of occupational workers and authorities needs to be increased regarding the use of personal protective equipment (PPE) and correct storage procedures, handling, disposing of pesticidesandempty containers.

In two field experiments, the effect of some weed control treatments (citric acid at the rate of 10, 15 and 20%, acetic acid at the rate of 20, 30 and 40%, oxadiargyl, oxyflurfen, rice straw mulch, hand hoeing and an unweeded check control treatment) on weed growth and onion productivity in sandy soils at the Agricultural Experimental Station of the National Research Centre, Egypt was studied. The results indicated that all weeded treatments reduced the dry weight of broadleaf, grassy and total weeds as compared with the weedy check. Oxadiargyl, followed by two hand hoeing, rice straw mulch and acetic acid 40% recorded the greatest weed control efficiency. Insignificant differences were noticed between these treatments. Applying rice straw mulch increased bulb length, bulb diameter, bulb weight and onion yield by 67.52, 57.55, 45.74 and 66.22% over the weedy check, respectively. The highest values of N, P and K were obtained from rice straw mulch treatment followed by hand hoeing, oxadiargyl and acetic acid 40% treatments. It may be concluded that farmers can certainly depend on mulching or acetic acid at 40% instead of using chemical herbicides especially in organic farm systems for controlling onion weeds.

Two field experiments were established at the Agricultural Experimental Station of the National Research Centre at Nubaria, Beheira Governorate, Egypt to study the herbicidal potential of the leaf extract of Eucalyptus citriodora at 5, 10, 15, 20 and 25% compared to two hand hoeing, unweeded treatments and the chemical herbicides Bentazon + Clethodium, Bentazon + Fluazifop-P-butyl and Butralin on pea plants and associated weeds. The results indicated that two hand hoeing achieved the maximum weed depression as expressed by the dry matter of total weeds. The dry matter of total weeds decreased by 95.08 to 94.77% as compared with unweeded treatment 50 and 70 days after sowing (DAS) followed by Butraline (93.93–94.65%), Bentazon + Clethodium (93.26–94.07%), Bentazon + Fluazifop- -P-butyl (91.82–92.77%) and leaf extract of Eucalyptus at 25% (91.61–91.95%). Furthermore, the reduction in weed development was accompanied by enhanced pea growth and yield. The results revealed that two hand hoeing was the best treatment to increase plant height, shoot dry weight and SPAD value at 50 and 70 DAS. Also, two hand hoeing produced the maximum values of pod length and number of seeds/pod. The results also indicated that Bentazon + Clethodium treatment gave observable values [recorded 72.96% in pod yield (ton ⋅ fed.–1) over that of unweeded control] of number of pod/plant, weight of pod/plant, seed yield/fed and protein percentage. Also, the results revealed great increases in the growth of pea as well as yield due to treatment with E. citriodora dry leaf extract at 25%. [recorded 64.8% in in pod yield (ton ⋅ fed.–1) over that of unweeded control]. So, the results indicated using Bentazon + Clethodium as well as E. citriodora dry leaf extract at 25% to control weeds associated with pea plants. The authors suggested application of E. citriodora dry leaf extract at 25% in controlling weeds associated with pea plants as a safe method that avoids environmental contamination.

Field evaluations of the efficiency of wheat genotypes and weed management treatments (pyroxsulam, isoproturon+diflufenican, mesosulfuron-methyl, hand weeding and control) and their interactive effects on wheat yield and associated weeds were performed during two successive seasons (2014/2015 and 2015/2016) at the agricultural experimental station of the National Research Centre, Nubaria, Egypt. Results showed that Gemmeiza-9 cultivar recorded the lowest values regarding dry weights of broadleaved, narrow-leaved and total weeds. Also, isoproturon+diflufenican achieved the maximum weed depression expressed in lowest dry material of broadleaved, narrow-leaved and whole weeds. The Gemmeiza-9 cultivar had the greatest plant height, number of spikes per m2, 1000 grains’ weight, and grain and straw yields per hectare. Moreover, the maximum values of the yield parameter were obtained from isoproturon+diflufenican application, followed by pyroxsulam and mesosulfuron-methyl. Application of isoproturon+diflufenican led to considerable anatomical effects on the leaves of either wheat or its associated weeds. In general, herbicide treatments caused a cell wall thickening and reduction in leaf and midrib thickness either in wheat or its associated weeds. Post-emergence herbicides (isoproturon+diflufenican) integrated with the Gemmeiza-9 genotype gave the highest values of productivity of wheat under sandy soil conditions.

Ascorbic acid (AsA) is considered as one of the most important and profusely known occurring water soluble antioxidants in plants, however, it is not well known to what extent this antioxidant might contribute in alleviating the adverse effects of water deficit on plant growth, yield and irrigation water use efficiency (IWUE). In attempt to clarify whether exogenous application of AsA could alleviate the adverse effects of water deficit on sunflower plants, two seasons (2014 and 2015) of field experimentation were conducted using six combinations of two AsA levels (AsA(–) and AsA(+), i.e. zero and 450 ppm AsA, respectively) and three irrigation water amounts (I100, I85, and I70, i.e. 100, 85 and 70% of crop evapotranspiration, respectively). Under water shortage, leaf chlorophyll content increased but proline content lowered in AsA–treated plants compared to the untreated ones. Lower values of LAI, head weight, seed yield ha–1, and oil yield ha–1 were recorded with decreasing water supply, while the highest values were gained when supplying plants with sufficient water (I100) plus application of AsA (i.e. AsA(+)), i.e., I100AsA(+). Plants under the latter treatment grew well and possessed higher yields compared to that of suffering from deficit water without AsA application, i.e. I85AsA(–) or I70AsA(–). Head weight and seed as well as oil yields ha–1 produced in 2014 season under sufficient water supply without AsA application (I100AsA(–)) could be achieved under moderately water–stressed condition in conjunction with applying AsA (I85AsA(+)). Implication of AsA tends to minimize the reduction in seed yield due to insufficient water supply, where I85AsA(+) and I85AsA(–), each saved same percentage of water (15.0%) but the reduction in seed yield associated the former treatment was less than that under the latter one. On the other hand, IWUE reached the maximal values in both seasons under I100AsA(+) treatment but, however, without marked differences in comparing to those recorded I85AsA(+) in 2014 season. Moreover, the differences in IWUE values exhibited by I100AsA(–) and I85AsA(+) did not reach the P

Abiotic stresses represent a major impediment to crop productivity, especially in arid regions. Thus, over two years of 2014 and 2015, a field experiment was undertaken at El Nubaria region, Egypt to assess the productivity and water use efficiency (WUE) of sunflower as affected by planting dates (April 21, May 21, and June 21) and irrigation levels (ET100%, ET85% and ET70%,). Results clarified that leaf chlorophyll a content was higher by sowing in May than in either April or June sowings, while leaf carotenoides of plant sown in May or June surpassed those sown in April. The minimal value of proline was obtained with sowing in May. Sowing in May increased plant height by 52.2 and 22.3 as well as LAI by 19.3 and 73.1% than sowing in April and June, respectively. The reductions in seed yield, oil yield and WUE amounted to 10.5 and 12.8, 13.7 and 18.3 as well as 11.8 and 9.8 % with April and June sowings, respectively, compared to May sowing. ET100% showed superiority over than ET85% and ET70% in improving sunflower yields and its attributes, but WUE did not affect. Sunflower sown in May and irrigated with ET100% gave the maximum values of seed yield and its attributes and WUE surpassing other interaction treatments. In June, WUE value increased under severe water deficit i.e. ET70% comparing to moderately water–stressed (ET85%) or well–watered conditions (ET100%).

To investigate the effect of faba bean plant populations (80000, 96000 and 120000 plants/feddan) resulted from the difference between hill spacing (30, 25 and 20 cm) and the efficiency of eight weed control treatments (butralin, metribuzin, oxadiargyl, each previous herbicides followed by one hand hoeing, two hand hoeing and unweeded check) on associated weeds, growth, yield and its attributes as well as chemical analysis. Two field experiments were conducted at the Experimental farm of El-Serw Research Station, Agricultural Research Center, Damietta Governorate, Egypt during winter seasons of 2015/2016 and 2016/2017. Main findings showed that increasing plant population from 80000 to 120000 plants/fedsignificantly decreased the broadleaved, grassy and total weeds dry weight by 46.32, 33.44 and 43.77% in the first season and by 45.99, 38.10 and 44.32% in the second season, respectively after 70 days from sowing. Plant population of 120000 plants/fed produced the highest values of plant height, dry weight/plant and LAI in both seasons. Moreover, sowing faba bean at 120000 plants/fedincreased seed yield/fed by 15.46 and 5.03% in the first season and 16.33 and 7.84% in the second season compared with 80000 and 96000 plants/fed, respectively. Two hand hoeing method significantly decreased the broadleaved, grassy and total weeds dry weight by 93.58, 99.24 and 95.68% in the first season and 92.62, 98.95 and 94.89% in the second season, respectively compared with the unweeded check. The results indicated that two hand hoeing method was the most superior treatment in increasing plant height, dry weight/plant and leaf area index at 70 and 90 days from sowing as well as yield, yield attributes and chemical composition of faba bean seeds followed by applying oxadiargyl herbicide with one hand hoeing treatment. It could be recommended that growing faba bean at plant population 120000 plants/fed integrated with two hand hoeing or oxadiargyl herbicide with one hand hoeing maximized seed yield per unit area.

Water stress reduces crop production significantly, and climate change has further aggravated the problem mainly in arid and semi-arid regions. This was the first study on the possible effects of β-sitosterol application in ameliorating the deleterious changes in wheat induced by water stress under field condition and drip irrigation regimes. A field experiment with the split-plot design was conducted, and wheat plants were foliar sprayed with four β-sitosterol (BBS) concentrations (0, 25, 75, and 100 mg L−1) and two irrigation regimes [50 and 100% of crop evapotranspiration (ETc)]. Water stress without BBS treatment reduced biological yield, grain yield, harvest index, and photosynthetic efficiency significantly by 28.9%, 42.8%, 19.6%, and 20.5% compared with the well-watered plants, respectively. Proline content increased in water-stressed and BSS-treated plants, owing to a significant role in cellular osmotic adjustment. Application of BSS was effective in reducing the generation of hydrogen peroxide (H2O2) and hence the malondialdehyde content significantly in water-stressed and well-watered wheat plants. Application of BSS up-regulated the activity of antioxidant enzymes (SOD, CAT, POD, and APX) significantly and increased the content of tocopherol, ascorbic acid, and carotene thereby reducing the levels of reactive oxygen species. The increased antioxidant system in BSS treated plants was further supported by the expression level of SOD and dehydrin genes in both water-stressed and well-watered plants. In the present study, the application of BBS at 100 mg L−1 was beneficial and can be recommended for improving the growth and yield of the wheat crop under water stress.

About 900.000 ha of Egypt’s agricultural lands are suffering from salinity build-up problem. Therefore, two field experiments were conducted in split-split plot design with four replications to study α‑tocopherols foliar application with 100 and 200 ppm and hand hoeing (two and three hand hoeing, plus unweeded) and their interactive effects on growth, osmoprotectants, mineral contents, seed yield, yield components, and nutritive value of the lupine plants and its associated weeds grown under salt-affected soil at 1.30, 3.20 and 4.23 dS m−1. Three hand hoeing treatment achieved the highest weed depression expressed in the lowest number and dry matter of broad-leaved, narrow-leaved and total weeds, and reduction % in dry matter were 80.75, 78.25 and 79.26 % compared with unweeded, respectively. Salinity stress significantly decreased total chlorophyll content, leaf area index and plant dry weight, while α‑tocopherol and hoeing increased in all previous traits relative to corresponding controls. Lupine seed yield, yield components, and oils, carbohydrates, proteins, carotenoids and alkaloids in the yielded seeds were significantly reduced by increasing salinity levels, meanwhile hoeing and α‑tocopherol treatments improved them. Total essential amino acids were decreased by increasing salinity levels and increased by increasing α‑tocopherol concentrations and number of hoeing treatments. It could be concluded that α‑tocopherol especially at 200 ppm partially alleviated the harmful effects of salinity stress on the growth of lupine plants and nutritive value of the yielded seeds. Three hand hoeing treatment was the optimum and safe method in controlling weeds associated with lupine plant grown under salinity stress.

Two field experiments were carried out in two successive seasons to examine the effect of weed management on wheat crop under saline condition and how herbicides can interact with foliar application with indole-3-acetic acid (IAA) to improve weed suppression and enhance crop growth and productivity under salinity stress. Clodinafop-propargyl was the best option to attain acceptable grassy weeds control. Increasing IAA from 0 up to 150 ppm significantly increased number and dry weight of grassy weeds in wheat after 80 days from sowing. Application of IAA at 150 ppm recorded the highest number and dry weight of weeds. Clodinafop-propargyl produced the lowest values of number and dry weight of weeds as well as nutrients uptake by weeds when water spraying was added. While application of IAA at 150 ppm gave the maximum values of flag leaf area, SPAD meter values, number of spike/m2, spike length, number of spikelets/spike, grains number/spike, grains weight/spike, as well as grain, straw, and total crude protein, phosphorus and potassium percentages when clodinafop-propargyl treatment was applied. It could be concluded that using IAA at 150 ppm resulted in enhancement of growth and productivity of wheat crop when integrated with clodinafop-propargyl treatment under salinity condition.

Water scarcity is considered as a key restriction for food production worldwide. Chitosan (Chi) and silicon (Si) play a crucial role in plants metabolic processes under normal or stress conditions. Field experiments were done at the Res. Station, Nat. Res. Cen., El-Nubaria Province, Egypt, in 2014/15 and 2015/16 seasons in a split-plot based on randomized complete block design with three replications, for assessing the defensive role of Chi and/or Si on wheat growth, yield, some physio-anatomical attributes and water use efficiency under different irrigation regimes. The experimental treatments included three irrigation water regimes (100, 70, and 40% of drip irrigation water requirement "IWR") as the main factor, as well as Chi and/or Si (water, 125 mg L−1 Si, 250 mg L−1 Chi, and 125 mg L−1 Si+250 mg L−1 Chi) as the sub-factor. Water deficit significantly decreases plant growth, yield, photosynthetic pigment, and relative water content; whereas significantly induced noticeable changes in leaf and stem anatomy as well as organelle's ultrastructure. Application of Chi + Si gave the highest plant growth and yield attributes, maintaining plant water status, along with improved physiological trials under irrigation regimes. Additionally, the application of Chi + Si under severe drought showed an ameliorative effect on cell ultrastructure compared with drought-affected plants only including well-developed chloroplasts, increased plastoglobules and maintained nucleus and mitochondria structure. Overall, this investigation proposes that the application of 125 mg L−1 Si plus 250 mg L−1 Chi twice at 50 and 70 days from sowing had potential to mitigate the water deficit effects, improving water use efficiency as well as increasing the wheat yield and its quality.

Two Field experiments were conducted during the two summer seasons of 2007 and 2008 at EL-Serw Agricultural Research Station, Damietta Governorate, Egypt to study the effect of the time removal of weeds on associated weeds, growth, yield and its components in direct seeded rice in salinity land. Echinochilon crus – galli, Echinochilon colunum, Cyperus difformis, Cyperus longus and Dicanthium annulatum were the major weed species. Competition beyond 8 and 10 weeks from sowing and weed competition for the whole season caused drastic reduction in the panicle length, number of panicles / m2 weight of 1000grain and grain yield. Grain yield of rice increased significantly with the increase of the duration of weed-free period. Weed free for the whole season and weed free for 10,8,6 and 4 weeks from sowing and weed removal at 4 and 6 weeks from sowing gave good results in this respect in both seasons. The period during 4 and 6 weeks after sowing was found to be an important factor in crop/weed competition. Weed cause 20 to 95% yield loss. Direct seeded rice ecosystems are most vulnerable to weed competition. Weed free is the most common and predominant method of control and is cost-effective. In direct seeded rice emergence of weeds begins with the germinating rice seedlings. This leads to competition between weeds and crop right from the very early stages. The degree of yield losses would depend on the type of weeds and the stage and duration of their competition with the crop. It could be concluded that the critical period of weed competition in direct seeded rice among 4- 6 weeks from rice sowing, thus it's important to remove the weeds at this time.

Two field experiments were conducted during the 2005 and 2006 growing seasons at the Experimental Farm of the National Research Centre at Shalakan, Kalubia Governorate, Egypt, to study the response of maize yield and its components and associated weeds to two irrigation intervals (every 2 and 3 weeks), three weed management treatments (metribuzin herbicide, hoeing twice at 25 and 40 days from sowing and weedy check) and four N forms (ammonium sulfate, ammonium nitrate, urea and calcium nitrate). Results showed that irrigation every 2 weeks significantly decreased grassy and total weeds and NK uptake by weeds. Providing maize plants by irrigation every 2 weeks significantly increased chlorophyll a leaf content, yield and its components, grain P content and protein yield/fed. Hoeing twice was more effective than metribuzin herbicide for controlling grassy and total weeds and lowering N, P and K uptake by weeds. Application of metribuzin markedly increased chlorophyll a leaf content, while hoeing twice was the effective treatment for increasing yield and its components, except ear diameter, and enhanced grain N content, protein % and protein yield/fed. Calcium nitrate significantly decreased dry weight of grassy and total weeds and NK uptake by weeds. Adding ammonium nitrate markedly increased chlorophyll a leaf content, number of rows/ear, 100-kernel weight and grain yield/fed. Irrigation every 2 weeks with metribuzin treatment gave the maximum values of 100-kernel weight, ear yield and grain yield /fed when ammonium nitrate as nitrogen form was used.

Dois experimentos de campo foram conduzidos na fazenda experimental do Centro de Pesquisa Nacional em Shalakan, Kalubia Governorate, Egito, durante 2006 e 2007, para estudar o efeito de tres herbicidas de pre-emergencia, prometryn [doses de 0.75, 1.5 e 2.25 kg ha-1], oxadiargyl [doses de 240, 480 e 720 g ha-1] e butralin [doses de 1.20, 2.40 e 3.36 kg ha-1], dois tratamentos capinados e um controle sem capina, avaliando a infestacao de plantas daninhas, a nodulacao, o crescimento, o rendimento, e os componentes do rendimento em plantas de soja. Dois tratamentos resultaram em maior reducao de plantas daninhas expressa em menores pesos frescos e secos das plantas dicotiledoneas, gramineas e total. A percentagem de materias das plantas daninhas comparada ao tratamento sem capina foi de 98.3, 92.64 e 96.9% em dicotiledoneas, gramineas e total de plantas infestantes, respectivamente. A aplicacao de tres herbicidas em doses maiores ou nas doses recomendadas reduziu significantemente o peso fresco e seco das plantas daninhas comparado com o tratamento com capina. Os resultados indicaram que todos os tres herbicidas nas maiores doses diminuiram o numero, peso fresco e seco dos nodulos, raiz, caule e peso seco total da planta, enquanto duas capinas manuais aumentaram significativamente das caracteristicas citadas. Duas capinas manuais e os herbicidas de pre-emergencia aplicados nas doses recomendadas aumentaram o rendimento da soja e seus atributos. Duas capinas manuais produziram maiores numeros de vagens por planta, peso de vagem por planta e numero de sementes por planta em 140,7; 150,0 e 59,8%, respectivamente, comparado ao tratamento capinado. Por outro lado, oxadiargyl aplicado na dose recomendada (480 g ha-1) apresentou maior rendimento de semente (g planta-1), rendimento de semente (kg ha-1) e rendimento biologico (g planta-1) que o tratamento sem capina em 87,3; 85,0 e 88,2%, respectivamente. Prometryn na dose de 1,50 kg ha-1, seguido de duas capinas manuais produziu a maior percentagem de proteina na parte aerea e sementes como tambem de oleo na semente, comparado a outros tratamentos de controle de plantas daninhas.

This study was carried out during two succes-sive seasons 2005 and 2006 on Anna apple trees budded on Balady apple rootstock, grown in sandy soil at (4 x 4m) apart under drip irrigation system, in a private farm at El-Khatatba, Monofia Gover-norate. A comparative study of some weed control treatments have been studied on Anna apple trees with its associated weeds. The tested weed control methods were using different colours of polyeth-ylene for mulching (green, blue, red, black and transparent), rice straw mulch, hand hoeing twice and two herbicides (Glyfosinate and Glyphosate) comparing with unweeded (control). All weed control treatments revented a significant reduction in fresh and dry weight of annual broad-leaved weeds, annual grasses, perennial and total weeds as compared with un weeded. The most effective treatments in decreasing fresh and dry weight of annual broad-leaves weeds were rice straw mulch-ing, followed by black polyethylene mulch and Glyfosinate. While, rice straw, black polyethylene and Glyphosate treatments were the most effective in decreasing fresh and dry weight of grass and total weeds. Also, the highest decrement in fresh and dry weight of perennial weeds were obtained by rice straw mulching and Glyphosate treatments. Moreover, results showed a remarkable improve-ment in growth, nutritional status of apple trees and yield (kg/tree). Also, physical and chemical properties of the fruits were improved. The most pronounced treatment developed under such study on the growth reduction of different grown weeds, meanwhile increased the apple tree growth, fruit yield associated with higher fruit quality was in rice straw mulching, black polyethylene mulching, Glyphosate treatments followed by hand hoeing twice treatment.Finally, it could be concluded that soil mulch-ing with rice straw can be used as a method for weed control in apple orchards. This method de-veloped such advantages over herbicides, polyeth-ylene mulch and hand hoeing in this concern. The possibility of using rice straw mulch for their many positive effects such as low coasts, in har-mony with ecosystem without no harmful residual effect especially for exported fruits and for pro-ducing safe fruits for human nutrition. In addi-tions, soil mulch with rice straw improving growth, leaves mineral contents as well as pro-duced higher yield and better quality of apple fruits.

Weeds represent the most serious problem in wheat in Egypt. For their control, two field exper-iments were carried out during two winter seasons (2004/2005) and (2005/2006) at National Re-search Centre experimental station at Shalakan, Kalubia Governorate. Some groups of herbicides (Dirby, Harmony extra, Granstar, Ecopart, Illoxan, Topic and Arelon) as well as hand weeding and unweeded treatments were evaluated in wheat. In addition, herbicide combinations were also as-sessed. Harmony extra at 24 g / fed. provided ac-ceptable control for broad leaved weeds but failed to control completely narrow-leaved weeds. Topic at 140 g / fed. provided great control of narrow weeds (97.68% reduction in dry weight after 90 days from sowing). Mixtures of both Harmony extra +Topic at rates (18 g / fed. +105 g / fed.) were better than Harmony extra alone for weed control (99.19 % control, 90 days after sowing) and grain yield. Concerning the other herbicides, Granstar + Topic were effective in controlling both broad and narrow weeds. The efficacy of Harmony extra + Illoxan was lower (91.2% con-trol). Overall, Arelon or mixture of Harmony extra +Topic were the most effective treatments with regard to weed control and wheat growth, yield and its attributes. However, no carryover damage with all used herbicides was observed on wheat. Estimating individual amino acids in the yielded grain revealed increase in essential and nonessen-tial amino acids due to single or combined appli-cation of herbicides. Pronounced increase was recorded with Harmony extra and Topic

Organic crop production, whether for export or local consumption, is increasing to avoid the residual effects of synthetic herbicides in foods, soil, and water, toxicity to other nontarget organisms, and herbicide-resistant weed populations. Organic farmers consistently ranked weed management as one of their most important production problems. Therefore, a 2-year study was conducted under 15-year-old mandarin trees to compare the effects of rice straw mulch, cattail mulch, black plastic mulch, hand hoeing, cultivation, glyphosate, and unweeded control treatments on weed control, fruit yield, and fruit quality. The greatest control (94%–100%) of weeds occurred with the plastic mulch (200 or 150 μm) and three mulch layers of rice straw or cattail. Covering soil with cattail or rice straw mulch (two layers) gave 85% to 98% control of weeds. Uncontrolled weeds in the weedy control caused significant reduction in yield and fruit quality and decreased the yield/tree by 62% compared with hand hoe treatment. Plastic mulches of 200 and 150 μm, cattail (Cyprus articulatus L.) mulch (two or three layers) and two mulch layers of rice (Oryza sativa L.) straw treatments significantly increased the fruit yield/tree by 24%, 18%, 20%, 11%, and 12% more than cultivation treatment, respectively, without significant differences among these superior treatments. Soil mulching with three layers of rice straw, cultivation, glyphosate, and 80-μm plastic mulch treatments caused a significant reduction in weed density and weed biomass, but gave lower yield than superior treatments. Total soluble solids of fruits was unaffected by any of the weed management strategies, whereas values of total acidity and vitamin C were significantly lower in the unwedded control than most weeded treatments. These results demonstrate that two layers of cattail or rice straw mulch could be used effectively for controlling weeds in citrus groves. Their effectiveness in controlling weeds may increase their use in agriculture systems with a concomitant decrease in the need for synthetic herbicides. Further studies are needed to evaluate their side effects on beneficial organisms, diseases, and insects.