Introduction: One of the most important factors reducing the yield of agricultural products is the competition from weeds. Weeds are considered as one of the complementary components of agricultural ecosystems and an integral part of agricultural systems. Due to the destructive effects caused by competition on the yield of crops, weeds are known as an undesirable part of agricultural ecosystems and are considered one of the most important factors that reduce crop yields. Weed control is usually listed as one of the advantages of intercropping. In mixed cultivation, due to various reasons such as increased vegetation cover, increased competition, and higher initial growth rate, the amount and invasion of weeds is significantly reduced. Therefore, mixed cropping can significantly reduce the amount of herbicides used, and this, in addition to the economic value, is of great environmental importance. In studies, mixed cropping system has been mentioned as an option for integrated management of weeds, especially in low-input farming systems. The most important damage caused by weeds to agricultural plants is the reduction of their yield through competition in the absorption of nutrients and growth inputs. One of the important measures in controlling weeds from the point of view of sustainable agriculture is the use of mixed crops of different crops. Therefore, according to the importance of intercropping in sustainable agriculture of crops and garden plants, this research aims to investigate the yield and yield components of canola (Brassica napus L.) in intercropping with safflower (Carthamus tinctorius L.) under control and non-control conditions. 
Materials and methods: For this purpose, a factorial experiment was carried out in the form of a randomized complete block design with three replications in Maragheh city. The first factor includes weed control at two levels (control and non-control weed) and the second factor includes different patterns of mixed cropping at 4 levels, including mixed cropping replacing safflower and canola, respectively, with ratios of 1:1 and 2:1 and mixed cultivation of safflower and canola 100:50, 100:75 and pure cultivation of safflower and canola were considered.
Results and Discussion: In canola, the highest biological yield (7990 kg/ha) and seed (2786 kg/ha) related to pure canola treatment with complete weed control was observed. The lowest biological yield was related to the 100:50 mixed cropping treatment (safflower-canola) with 3865 kg. The lowest grain yield related to the treatment combination of 100:50 (safflower-canola) mixed cropping with non-control weed was obtained with an average of 654.6 kg/ha. The highest amount of 1000-seed weight was obtained in the treatment combination of 1:1 replacement mixed crop (safflower-canola) with complete weed control with an average of 2.7 gr. Also, the lowest amount of 1,000-seed weight was related to the treatment combination of 2:1 (safflower- canola) mixed cultivation with no weed control with 1.6 gr. The highest number of weeds was obtained in the main branches (33.4) and secondary branches (25.3) related to the treatment combination of 2:1 replacement mixed crop (safflower-canola) with complete weed control. Also, the lowest number of weeds in the main branch was related to the treatment combination of 100:75 (safflower-canola) with non-control weed with an average of 17.3, and the lowest number of weeds in the sub-branch was related to the 100:50 (safflower-canola) mixed cultivation with non-control weed with an average of 10 pods. According to the results of the average data comparison, the highest number of seeds in pod of the main branch was related to the treatment combination of 100:50 incremental mixed cultivation (safflower-canola) with full weed control, and the lowest number of seeds in pod of the main branch was related to the treatment combination of pure canola cultivation with non-control weed was obtained with an average of 15.4. Also, the highest number of seeds in the pod of the sub-branch of canola was obtained in the treatment combination of pure canola cultivation with complete weed control with an average of 22.3, and the lowest amount of seed number in the pod of the sub-branch related to the treatment combination of pure canola cultivation with non-control weed with an average of 15.
Conclusion: Among the different patterns of safflower and canola cultivation, the highest seed yield was obtained in pure cultivation and complete weed control. The yield and yield components in canola were affected by different patterns of mixed cropping and weed control treatment, so that the 2:1 planting pattern (safflower-canola) had more seeds and 1000-seed weight.