Effect of Water Stress and Weed Control on Weeds, Broomrape and Yield in Some Faba Bean Varieties

Broomrape and weeds are determining factors for faba bean cultivation in Egypt. In split split plot design for this reason two field experiments in clouded fifty treatments were conducted in naturally infested fields with weeds and broomrape (Orobanche crenata Forsk.) at Shandaweel Research Station, Sohag governorate during 2012/13 and 2013/14 winter seasons to study the effect of two water stress treatments (The irrigations regimes was 60% and 100% FC), five faba bean varieties namely (Giza843, Misr3, Nubaria1, Nubaria3 and Sakha4) and five weed control treatments Select-super at 500 cc/fed+ Basagran at 500 cc/fed+ Roundup twice at 75 cc/fed, Topik at 140 g/fed + Basagran at 500 cc/fed + Roundup twice at 75 cc/fed, Hand hoeing twice at 18, 30 DAS+ Hand pulling twice, Hand hoeing twice + Roundup twice at 75 cc/fed and untreated check on weeds, broomrape, faba bean seed yield and its components and water use efficiency. Results revealed that irrigation depletion at 60% FC decreased the dry weight of total weeds by 35.85 and 28.22% in first and sacond seasons as respectively compared with irrigation depletion at 100% FC. Irrigation at 100% FC decreased both number and dry weight of broomrape spikes/m by 31.90 and 30.44% in 2012/13 season and by 23.13 and 24.35% in 2013/14 season, respectively, delayed broomrape emergence above soil surface and increase faba bean seed yield /fed and its components compared with depletion at 60% FC in both seasons. Water consumptive use (CU) values were (992.5 and 737.1 m/fed.) for 100 and 60% FC treatment, respectively, in both seasons. The highest value of water use efficiency (WUE) recorded 1046.6 and 758.0 kg/m by using of irrigation at 60% FC in both seasons. The highest CU (882.5 and 935.6 m/fed.) and WUE (1.008 and 0.980 kg/m) were recorded 1.008 and by sown Sakka4 cultivar in both seasons, respectively. Excelled varieties of Nubaria1, Nubaria3 and Giza843 than other varieties and increase yield and its components by reducing the grassy and broad-leaved and total weeds in the both seasons. This due to the increased height of the plants, as well as increase the number of branches/plant compared other varieties. Varieties of Giza843 and Misr3 were brief and partially resistant to infection and Sakha4 was tolerant injured broomrape contrast while, Nubaria1 and 3, which were highly susceptible in both seasons. Weed control treatments decreased significantly the dry weight of grassy, broad-leaved and total weeds, numbers and weight of broomrape spikes and delayed broomrape emergence above soil surface of broomrape and gave the highest values of yield and yield components in both seasons. The best treatments were (Select-super +Basagran+ Roundup twice) and hand hoeing twice at 18, 30 DAS+ Hand pulling twice in both seasons. The interactions between irrigation regimes X varieties, irrigation regimes X weed control treatments, varieties X weed control treatments and irrigation regimes X varieties X weed control treatments decreased significantly the dry weight of weeds, number and dry weight of broomrape spikes in both seasons than unweeded check. So, the best seed yield was obtained from the interaction between growing faba bean variety (Giza843 and Misr3) combined with hand hoeing twice+ Roundup twice) or (Select-super +Basagran+ Roundup twice) under irrigation at 100% FC in both seasons. From this study it can be recommended for the cultivation of Giza 843 and Misr3 because it relatively resistant to infection broomrape or agriculture product was Sakha4 because it broomrape tolerant of injury. Irrigation can also be at 60% FC to minimize water consumption and getting to making seed yield of faba bean relatively reasonable. You can also use herbicide (Select-super at 500 cc/fed + Basagran at 500 cc/fed + Roundup twice at 75 cc/fed) to get the highest percentage control of weeds and broomrape and the highest seed yield of faba bean.