Interaction effect of cultivar and living mulch on sunflower yield and weed control

In order to evaluate the effects of crop cultivars and living mulchon sunflower yield and weed control، a field experiment was carried out as factorial arrangement based on a randomized complete block design with three replications in 2013. Treatements were sunflower cultivars (‘Azargol’، ‘Allstar’، ‘Farokh’) and weed control treatments (weed-free، weed-infestation and intercropping of Fagopyrum esculentum، Medicago scutellata، Vicia villosa as living mulch alone and in combination with one hand-weeding). In comparison to weedy treatement، F. esculentum، M. scutellataand V. villosa cover crops were reduced total weed biomass 43. 7، 33. 8 and 25 percent، and weed density 57. 1، 38. 1 and 29، respectively. Weed control was improved significantly when cover crops used in combination with one hand-weeding. The lowest weed biomass and density were recorded in the ‘Azargol’ cultivar. The highest Sunflower leaf area index (LAI) was obtained in ‘Azargol’ cultivar under weed-free condition. Weed interference decreased grain yield of ‘Azargol’، ‘Allstar’ and ‘Farokh’ by 18. 6، 22. 1 and 33. 4 percent، respectively compared to weed-free plots. The highest grain yield was obtained in ‘Azargol’ cultivar. Medicago scutellataas cover crop in combination with one hand weeding resulted in yields similar to the weed-free treatment. Overall، the results of this study revealed that the use of M. scutellataas living mulch and ‘Azargol’ as competitor cultivar can be used as part of an integrated weed management for sustainable sunflower production.