Broomrape is a determining factor for faba bean cultivation in Egypt especially under sandy soil conditions. For this reason two field experiments were conducted in naturally infested fields with broomrape under sandy soil conditions at Ismailia Agricultural Research Station, Ismailia governorate during 2014/15 and 2015/16 winter seasons to study the effect of degree interaction between three faba bean varieties namely Giza843, Misr3 and Giza 3, two seeding rates at 30 and 60kg seed/fed. and two broomrape control treatments namely Roundup twice at 75 cc/fed. and untreated check on broomrape management and faba bean productivity. A split split plot design with three replicates was used, faba bean varieties were assigned to the main plots and seeding rates were allocated in sub plots, while weed control treatments were distributed randomly in sub sub plots. Results revealed that both faba bean varieties Misr3 and Giza843 exhibited significant decrease in numbers and weight of broomrape spikes/m2 estimated by 87.0 and 91.0% & 49.2 and 53.3 % in 2014/15 winter season and by 86.1 and 90.6% & 47.9 and 54.5 % in 2015/16 winter season, respectively as compared with the susceptible variety Giza 3. Faba bean varieties Misr3 and Giza843 significantly increased faba bean yield and its components in both seasons as compared with variety Giza 3. Seed rate of 30kg/fed. significantly decreased the number and weight of broomrape spikes/m2 by 16.8 and 11.5% in 2014/15 winter season and by 15.3 and 18.0% in 2015/16 winter season, respectively as compared to seed rate of 60kg/fed. Seed rate of 30kg/fed. significantly increased faba bean yield components in both seasons except plant height and seed yield (ardab/fed.) which significantly decreased with seed rate of 30kg/fed. in both seasons as compared to seed rate of 60kg/fed. Roundup applied twice significantly decreased the number and dry weight of broomrape spikes/m2 by 75.2 and 73.1% in the first seasons and by 72.6 and 69.8% in the second season, respectively, as compared with untreated check. Roundup applied twice significantly increased faba bean yield and its components in both seasons as compared with untreated check. The increases in seed yield (ardab/fed.) were 89.1 and 86.3% in the first and second seasons, respectively, as compared with untreated check. Analysis of the role of studied broomrape control measures and their possible integration was analyzed and correlation between broomrape infestation levels with faba bean seed yield was negative. Thus, from this study the best control package for growing faba bean in sandy soil infested with broomrape is by planting Misr 3 or Giza 843 cultivars through November with 2 sprays of Roundup at 30 kg/seeding rate in infested fields with broomrape in Ismailia area.

Under drip irrigation condition, two field experiments of sugar beet (Beta vulgaris L.) were conducted, in sandy soil, at El-Bostan area, Aly Mubarak Experimental Farm, Southern El-Tahrir Region, El-Buhira Governorate, Egypt, during 2013/14 and 2014/15 winter seasons, to evaluate the impact of water deficit irrigation and its relation with the critical period of weeds infestation on sugar beet yield, quality and water use efficiency. The experimental design was a split-plot design, where three water irrigation regimes treatments, i.e. 60, 80 and 100 % of evapotranspiration (ET 0), were allocated in the main plots, and the ten weed removal intervals were allocated in the sub-plots which included five weed free for 3, 6, 9, 12 weeks after planting (WAP) and weed free the whole season, and five weed infestation for 3, 6, 9, 12 (WAP) and weed infestation for the whole season. The main findings indicated that the highest significant reduction on the fresh weights of grassy, broad-leaved and total weeds was obtained by irrigation at 60 % ET 0 by14.8, 16.0 and 15.6 %, respectively, in 2013/14 season and 25.0, 13.6 and 17.3 %, respectively, in 2014/15 season, as compared to 100 % ET 0 , which reflected in increases on root and gross sugar yield per faddan by 58.8 and 60.2 %, respectively, in 2013/14 season and 65.5 and 40.1 %, respectively, in 2014/15 season, as compared to irrigation at 100 % ET 0. Furthermore, water use efficiency of irrigation at 60% ET 0 gave the highest values of root and sugar yield by 7.2 and 1.2 kg/m 3 , respectively, in the first season and 7.1 and 1.3 kg/m 3 , respectively, in second season. The dominant annual weeds were the broadleaf weeds with infestation rates 3.0 kg and 3.5 kg fresh weight /m 2 in the first and second seasons, respectively. Whilst, the infestation rate of the grassy weeds was 1.3 kg and 1.4 kg fresh weight/m 2 in the both seasons, respectively. In the both seasons, the highest reduction on the fresh weight of the two weeds categories and their total was obtained from all weed free and weed infestation treatments (> 90 %) as compared to weed infestation for the whole season, except with weed free for 3 weeks (< 70%). These results reflected on sugar beet yields (ton/fed). In the first season, the significant increasing on dry weight of tops, roots and the gross sugar yield (ton/fed) was between 118.6, 302.5 and 353.8 %, respectively, in weed free for the whole season to 58.5 % for tops by weed free for 3 weeks, 135.2 % for roots by weed free for 6 weeks and 50.0 % for gross sugar yield by weed infestation for 9 weeks, as compared to weed infestation for the whole season. In second season, the significant increasing on dry weight of the tops, roots and gross sugar yield (ton/fed) was between 98.8, 311.3 and 288.7 %, respectively, in weed free for the whole season to 37.5 % for the tops and 35.0 % for the roots in weed free for 3 weeks and 106.5 % in weed infestation for 6 weeks, as compared to weed infestation for the whole season. While, the rest weed free and weed infestat...

Two field experiments were conducted in a highly calcareous sandy clay loam soil at Nubaria Agric. Res. Station, Agric. Res. Center, Behera Governorate, Egypt during 2012 and 2013 seasons. The objectives were to study the effect of critical weed competition period on plant growth, seed cotton yield, its components and fiber properties of the Egyptian long-staple cotton cultivar Giza 86. The experimental design was a complete randomized block design with four replications. Each experiment included fourteen treatments in two groups, the first group included seven weed-free periods which were weed-free for the 3, 6, 9, 12, 15, 18 weeks from sowing and weed-free for the whole season, respectively, and the second included seven weed competition periods which were weed competition for the 3, 6, 9, 12, 15, 18 weeks from sowing and weed competition for the whole season, respectively. Results indicated that the fresh weight (g/m 2 ) of broad leaf weeds, grassy weeds and total annual weeds decreased by 93.1, 93.7 and 93.3%, respectively, with increasing weed removal periods to 18 weeks from sowing as compared with weed competition for the whole season treatment. Also, the effect of weed removal and weed competition periods were not statistically significant on position of 1 st sympodial node, no. of open bolls and no. of non open bolls/plant, where as the effect was statistically significant on the plant height, no. of sympodial branches/plant and no. of monopodial branches/plant. Weed competition for the whole season reduced seed cotton yield per feddan by 41.1% as compared with weed-free for the whole season. The results showed that the critical period of weed competition to cotton crop start 3 weeks after planting and continue until 18 weeks from planting and the critical competition point where yield losses from early or late competition after 15 weeks from planting were equal. From these results, weed control strategies in cotton should be done through 3-18 weeks from planting and cotton can be considered as week competition for weeds especially in the earlier periods of growth, which extend to the fifteen week from planting. All fiber properties were not affected significantly by weed removal and weed competition periods, except fiber strength.

Allelopathy is a natural which may prove to be a unique tool for weed control treatments and thereby increase some crop yields. Two experiments were conducted in naturally infested fields with broomrape (Orobanche crenata Forsk.) at Shandaweel Research Station, Sohag Governorate during 2013/14 and 2014/15 winter seasons. The aim of this work was to study the effect of crop sequences for producing allelopathic (cotton, sorghum and maize), two faba bean varieties (Giza-843 and Giza-40) and two plant densities (one side of the ridge and two sides of the ridge) in a split split-plot design were used to study the control of broomrape in faba bean. Results showed that sowing of maize before faba bean decreased significantly numbers and weight of broomrape spikes by 32.0 & 18.5% in the first season and by 37.7 & 37.5% in second season and lead to increase in number of days to broomrape emergence above soil surface by 18.5 & 16.6% in both seasons, respectively, compared to cotton and sorghum. Faba bean seed yield and components were increased by sowing faba bean after maize compared with faba bean after cotton and sorghum. While, faba bean after maize increased the seed yield of faba bean by 13.8 and 13.6 % in both seasons, respectively. Sowing of cotton before faba bean increased significantly the plant height, weight of pods/plant, weight of seeds/plant, 100-seed weight and seed yield (ardab/fed) by 3.9, 5.2, 4.9, 4.8 and 5.8% in 1 st season, respectively, and by 9.1, 2.0, 3.5, 4.7 and 5.5% in 2 nd season, receptively, compared with sowing of sorghum before faba bean. Number, weight and days emergence of broomrape above the soil surface were significantly affected with varieties of faba bean. Superiority of Giza 843 over Giza 40 was by 30.7 and 16.8% in the first season and by 39.7 and 37.5% in the second season. Late-onset broomrape above the surface of the soil with the cultivation of Giza 843 was by 16.8 and 22.5% in the first and second seasons, respectively. Varieties of (vicia faba) were significantly increased on yield ( plant height, weight of pods/plant, weight of seeds/plant, 100seed weight and seed yield/fed) in both seasons. Seed yield of faba bean was increased at cultivation of Giza 843 by 39.7 and 37.5% in the respective 1 st and 2 nd seasons, respectively, compared with Giza 40. Plant density showed significant effect on the number and weight of broomrape and days of number emergence of broomrape above the soil surface. Increasing plant density from 13 to 26 plants/m 2 increased the number and dry weight of broomrape/m 2 by (25.5 and 36.7%) and (29.3 and 28.6%) in both seasons, respectively. Faba plant height, weight of pods/plant, weight of seeds/plant, 100-seed weight and seed yield (ardab/fed) significantly affected was plant density in both seasons. The seed yield of faba bean cultivation was increased at the rate of 26 plants/m 2 by 5.58 and 4.91% in both seasons, respectively, compared to faba density of 13 plants/m 2 . The interaction between crop sequences for producing allelopathic, faba variet...