A filed experiment was carried out at Al-Mattana Agricultural Research station, Agricultural Research Center, Luxor Governorate during 2015/16 and 2016/17 seasons, to study the effect of intercropping soybean (cover crop) with sugarcane crop, sole sugarcane and weed control treatments i.e. (Stomp at 1.75 l/f. hand hoeing twice at 25 and 45 days after planting and unweeded check) as the integrated weed control on fresh and dry weight of weeds (g/m2) and yield of primary crop (sugarcane) and secondary crop (soybean) which intercropping with sugarcane in natural infested soil by weeds. The experiment was laid out in randomized complete block design (RCBD) under split plot arrogant with four replication, intercropping treatments was put in the main plots and weed control treatment in split plots with four replications for each treatment.

Two field experiments were carried out at in clay soil in Agricultural Research and Experimental Center of Agriculture at Faculty of Moshtohor, Benha University, Kalubia Governorate during 2009 & 2010 summer seasons to determine the critical period of weed competition between weeds and soybean crop through use of regression and economic approaches and also determine the relationship between weeds and soybean yield under three plant densities (105, 140 and 175 thousand plant/ fad.) and ten treatments in two types of treatments (in the first type soybean was hand weeded for different periods 3, 6, 9 and 12 weeks after sowing (W.A.S.) and for whole season ,then no further weeding was done while, in the second type weeds were allowed to grow for different periods at 3, 6, 9 (W.A.S.) until harvest the weeds were removed by hand- weeded and weed competition treatment for whole season on seed yield of soybean and associated weeds.
The main results showed that, maximum yield losses of soybean due to weed competition in the whole season were 37.6 and 34.4 % from weed free treatments in 2009 and 2010 seasons. Mathematical model for the relationship between weed free and weed competition periods according to the recommended losing yield value (10), clear that critical period of weed competition under 105 thousand plants density/fad., were (6.5 and 7.0) weeks for weed free as well as (4.25 and 4.25) for weed competition in 2009 and 2010 seasons, respectively. Under 140 thousand plant density the respective values were (6.2 and 6.3) weeks for weed free as well as (3.9 and 4.2) for weed competition and for 175 thousand plant density were (5.9 and 5.6) weeks for weed free as well as (3.5 and4.15) weeks for weed competition in 2009 and 2010 seasons, respectively . The critical period of weed treatments over plant densities were (6.45 and 6.4) weeks for weed free as well as (4.9 and 4.65) weeks for weed competition in 2009 and 2010 seasons, respectively. All weed competition exerted significant efficiency in controlling annual weeds. Weed free for the whole season treatment gave the best control for annual weeds gave the highest values of yield and yield components in two seasons. The sowing 175000 plant/fad. gave the lowest weight for dry weight for annual weeds and the tallest plants in first and second seasons. 105000 plant/fad., gave the best values of No. of branches and seed weight/plant in the first and second seasons. 140000 plant/fad., gave the highest value of No. of seed pod, weight of 100 seed and yield ton/fad. in the two seasons. Plots weeded at 3 and 6 week after sowing showed the best performance in all aspects of soybean. Such knowledge should be disseminated to farmers to keep soybean yield losses of weed competition to maintain maximum soybean seed yield. This study showed that negative correlation for annual weed weight and all studied characters under study.

Four field experiments were conducted at Sids Research Station, Agriculture Research Center, Beni Suef Governorate, Upper Egypt during 2010 and 2011 winter seasons. Two experiments were carried out to estimate the impact of fourteen treatments i. e. seven intervals of weed competition (weed infestation) and seven intervals of weeds removal (weed free), with two weeks interval between each treatment which began from sowing. Another two experiments were conducted to evaluate the efficacy of some herbicides i. e. Amex at 1.75 L./fad., Stomp extra at 1.7 L./fad., Starane at 150 cm3/fad. + Fusilade super at 0.5 L./fad.; and Sencor at 100 g/fad. + Fusilade super at 0.5 L./fad. and Iquopart at 200 cm 3/fad. + Fusilade super at 0.5 L./fad. as well as hand weeding twice and unweeded check on controlling annual weeds associated with onion transplants and its effects reflection on onion transplanting yields.
The main findings of these studies showed that the weed infestation rate under onion nursery field was 2.4 and 2.5 kg fresh weight/m2, which reduced yield of onion transplants per faddan by 80 and 75.9% competition treatment of onion transplant for whole season in both 2010 and 2011, respectively, compared with weed free for whole season treatment. Also, results show that the quadratic equations which had highest R2 (0.986 and 0.984) for weed free period and (0.962 and 0.957) for weed competition durations in 2010 and 2011 seasons, respectively. They results were fit to represent the data of critical periods of weed competition to onion nursery and ten weeks period is required to be weed free to obtain the maximum yield of onion transplants and two weeks of weeds infestation can be allowed without onion transplants yield reduction.
On other hand, the use of Iquopart at the rate of 200 cm3/fad. plus Fusilade super at the rate of 0.5 L./fad gave the highest controlling percentages of the annual broad leaf and grassy weeds with the highest values of onion transplant( yield and quality) without damage on chlorophyll pigments in the onion transplants can be advised for weed control in mentioned critical period of onion nursery.

Two field experiments were conducted at Sids Horticulture Research Station, Beni Suef Governorate, Egypt, during the two successive seasons of 2009/2010 and 2010/2011.This study carried out to evaluate the efficiency of some chemical weed control treatments as pendimethalin(Stomp extra45.5%CSatrate at rate of 1.7 Liter/fad. ),butralin(Amex 48% EC at rate of 2.5 Liter/fad.) and fluroxypyr (Starane 20% EC at rate of 200 cm3/fad.) alone or with hand hoeing once or twice on weed, balady garlic yield and yield components and residues limits for herbicides.
The obtained results revealed that hand hoeing treatment at three times gave highest fresh and cured yield followed by treatments with Stomp extra 1.7 L. /fad.+ two hand hoeing and Starane 200 cm3 /fad.+ two hand hoeing. While the lowest values of fresh and cured yield were obtained from control (without) followed by Starane, Amex and Stomp extra alone. These results may be due to the better effect of hoeing on removing weeds than herbicides and poor effect of herbicides in killing the weeds especially when used alone. There are residual effects for using herbicides but there were below detection limit 0.01 ppm for butralin 48% at 2.5 L/ fad. & pendimethalin 45.5% at 1.7 L/fad. and 1.0 ppm for fluroxypyr 200 cm3 /fad. in cloves.
Keywords: Herbicides – hand hoeing – residues-Garlic

Two field experiments were conducted during successive seasons of 2008/2009 and 2009/2010 at Sakha Agricultural Research Station to study the effect of herbicides and urea as an additive to herbicides on wheat, NPK uptake, photosynthetic pigments and associated weeds. The results indicated that using the recommended rate of herbicides, (isoproturon + diflufenican) at 300g a.i./fed. for control total annual weeds, tribenuron-methyl at 6.0g a.i/fed. for control broad-leaved weeds and clodinafop propargyl at 21g a.i./fed for control grassy weeds as applied alone post- emergence as well as hand weeding twice, gave excellent weed control (93.6, 68.0, 45.9 and 93.6 % ), respectively. While, the same herbicides when applied at moderate rate (isoproturon + diflufenican) at 244.5g a.i./fed, tribenuron-methyl at 4.5g a.i /fed and clodinafop propargyl at 15.75g a.i/fed) mixing with 1% urea increased the herbicides efficiency in controlling the annual weeds by about ( 90.2, 65.9 and 44.5 %). Mixing 1% urea with the same herbicides at low rate (isoproturon + diflufenican at 165g a.i/fed, tribenuron-methyl at 3.0g a.i/fed and clodinafop propargyl at 10.5g a.i/fed) gave poor weed control and were significantly less efficient than the other treatments at the first survey in the first season.
Hand weeding treatment, (isoproturon + diflufenican), tribenuron-methyl and clodinafop propargyl at high rate, alone as post-emergence as well as the same herbicides at moderate rate plus 1% urea had higher efficiency in controlling annual weeds and increased the plant height, spike length, weight of grains/ spike, number of grains/spike, straw yield (ton/fed) and grains yield (Ardab/fed), compared with the other treatments used. All herbicidal treatments as well as hand weeding treatment increased protein, phosphors, potassium and carbohydrate percentages and their uptake kg/fed in wheat grains over control treatment. Data also, cleared that all herbicides treatments slightly decreased chlorophyll a, b and total chlorophyll and; increased carotene content. From results of correlation analysis the fresh weight of total weeds, grassy weeds and broad-leaved weeds biomass were negative correlated with wheat yield. Grassy weeds were more aggressive in their competitiveness effect than broad-leaved weeds on wheat yield and its components. These results indicated that under heavy infested with annual weeds, it is possible to apply herbicides i.e.(isoproturon + diflufenican) for annual weeds control, tribenuron-methyl for broad-leaved weeds control and clodinafop propargyl for grassy weeds control at high rate alone or same herbicides at moderate rates mixed with 1% urea. These findings revealed obviously that such weed control measure can minimize weed /wheat competition and consequently gave the highest reduction in weeds and increase wheat yield and its components.

The present work was conducted at El-Kanater Horticultural Research Station during 2009 and 2010 seasons, to study the effect of some weed control treatments i.e., two mulching types (black polyethylene plastic and straw of rice), Roundup 48 % herbicide and hand hoeing on some vegetative growth, fruiting parameters, fruit quality, leaf nutrient status as well as dry weight measurement of annual and perennial weed of "Le-Conte" pear trees budded on (P. communis L.) rootstock.
Data obtained revealed that all investigated weed control treatments exhibited a positive effect on weed and a significant increase in all studied vegetative growth measurements i.e., shoot length increase and number of leaves per shoot. Moreover, all investigated fruiting parameters (fruit set %, tree yield either kg or No. of fruits, yield as ton/fed and yield increment % in relation to the control) were improved and significantly increased as a result of using the weed control treatments in comparison the control treatment. Furthermore, results indicated that fruit physical characteristics such as fruit weight, volume, firmness and fruit dimension as well as fruit chemical properties i.e., TSS %, acidity %, TSS/acid ratio and fruit sugar content were improved by the different weed control treatments in most cases as compared to the control treatment.
On the other hand, controlling weed species accompanied the pear trees reflected on the previous results by some weed control treatments. It could be arranged in descending order with regard to their significant effect on reducing the dry weight of weed species associated pear trees as follows: Roundup at 4 l/fed., soil covering with both black polyethylene plastic and straw of rice and hand hoeing twice.
In general, it could be concluded that, both mulching treatments either with black polyethylene plastic or straw of rice were the most effective for improving vegetative growth and fruit quality as well as increasing both fruit set and fruit yield of "Le-Conte" pear trees. In addition, the first mulching treatment was more effective than the second one.

Abstract: Two field experiments were carried out during winter seasons of 2008/2009 and 2009/2010 at the Experimental Station of Agricultural Research Center, El-Serw Station Damietta Governorate, Egypt to study the effect of additives on the efficacy of Topik (Clodinafop-propargyl) and Traxos (Pinoxadin+Clodinafop+Safener) herbicides (with or without Arkopal N100) on weeds and wheat plants. The results indicated that all weed control treatments significantly reduced fresh, dry weight and caused significant increases in photosynthetic pigments after 75 days from sowing, yield, yield attributes and grain protein percent. In addition anatomical structure is a significant leaf dysfunction constitutes a part of the killing action of the specific herbicide on target weeds. Traxos at 500 cm3 tank-mixed with Arkopal N100 at 4 and 8 % followed by Topik at 140g tank-mixed with adjuvant at 4%, Traxos at 375 cm3 tank-mixed with adjuvant at 8%, Topik at 140 and 105g tank-mixed with adjuvant at 8%, Traxos at 375 cm3 and Topik at 126 g tank-mixed with adjuvant at 4% treatments, respectively recorded the highest reduction of weeds and recorded the highest values of photosynthetic concentrations as well as, increased significantly produced higher number of spike/ m2, grain yield , straw yield, crop index and grain protein % when compared with unweeded control in both seasons. On the other side, the lowest effective on the other self characters were by using Traxos at 500 cm3 alone and Topik at 140g alone and hand weeding twice at 30 and 45 days after sowing respectively gave less effective when compared with all other treatments and unweeded control in both seasons. While, a non significant effect due to weed control treatments 1000 grain weight, phosphorus and potassium percentage in grain .

Abstract: Two field experiments were carried out during winter seasons of 2008/2009 and 2009/2010 at the Experimental Station of Agricultural Research Center, El-Serw Station Damietta Governorate, Egypt to study the effect of additives on the efficacy of Topik (Clodinafop-propargyl) and Traxos (Pinoxadin+Clodinafop+Safener) herbicides (with or without Arkopal N100) on weeds and wheat plants. The results indicated that all weed control treatments significantly reduced fresh, dry weight and caused significant increases in photosynthetic pigments after 75 days from sowing, yield, yield attributes and grain protein percent. In addition anatomical structure is a significant leaf dysfunction constitutes a part of the killing action of the specific herbicide on target weeds. Traxos at 500 cm3 tank-mixed with Arkopal N100 at 4 and 8 % followed by Topik at 140g tank-mixed with adjuvant at 4%, Traxos at 375 cm3 tank-mixed with adjuvant at 8%, Topik at 140 and 105g tank-mixed with adjuvant at 8%, Traxos at 375 cm3 and Topik at 126 g tank-mixed with adjuvant at 4% treatments, respectively recorded the highest reduction of weeds and recorded the highest values of photosynthetic concentrations as well as, increased significantly produced higher number of spike/ m2, grain yield , straw yield, crop index and grain protein % when compared with unweeded control in both seasons. On the other side, the lowest effective on the other self characters were by using Traxos at 500 cm3 alone and Topik at 140g alone and hand weeding twice at 30 and 45 days after sowing respectively gave less effective when compared with all other treatments and unweeded control in both seasons. While, a non significant effect due to weed control treatments 1000 grain weight, phosphorus and potassium percentage in grain .

A series of experiments were carried out, in wheat fields at Sids Agricultural Research Station in three successive winter seasons 2005/2006, 2006/2007 and 2007/2008, in addition to five pot experiments in Weed Research, Laboratory FCRI, ARC, Giza in 2009/2010 winter season. The objective of the this study was to determine the tolerance of wheat and barley crops and susceptibility of three winter common grassy weeds, i.e. Avena fatua (wild oat), Phalaris minor (canary grass) and Lolium temulentum (rye grass) to clodinafop propargyl (Topik 15% WP) at rates of 70, 140 and 210 g/fad at two times of applications, 30 and 45 days after sowing (DAS) as compared to unweeded check.
The main findings revealed that wheat was tolerant to the herbicide at the recommend rate (140 g/fad ) when applied 45 DAS whereas the herbicide was very effective against canary grass and increased wheat production at Sids. On the other hand, under pot experiments, wheat was tolerant to the herbicide at the three applied rates , 70, 140 and 210 g/fad applied 30 and 45 DAS as compared with barley which was sensitive to all studied rates. Topik at 210g/fad applied 30 DAS extremely inhibited chl a, chl b and carotenoid pigments of barley plants by 56.2, 64.2 and 70.1%, respectively. Furthermore, Topik at the three rates of 30 and 45 DAS gave a 100% reduction in A.fatua and P.minor, but, at rate of 70g/fad applied at 45 DAS , a reduction of 100% in A.fatua was achieved. Moreover, Topik at 140 and 210g/fad at both 30 and 45 DAS gave approximately 100% reduction of L.temulentum. These results suggest that clodinafop-propargyl (Topik 15% WP) should be used for controlling grassy weeds effectively in wheat, but farmers should be advised to avoid using this herbicide in barley fields due to its high phytotoxicity to barley, inspite of its efficacy on controlling grassy weeds.