Abstract: The effects of film mulching on weed control and yield in rapeseed under low-level fertilization were studied by setting three treatments： Biodegradable film （BE film）, polyethylene film （PE film） and no film mulching（control）. The results showed that under low level fertilization, both plant height and leaf number of rapeseed seedlings showed a serious deficiency of fertilizer. The correlation coefficient between lack of fertilizer state and N was above 0.95. Film mulching could effectively accelerate rape biomass accumulation. 45 days after emergence, compared to the control, plant height and leaf number of BE film and PE film were increased by an average of 3.8%, 5.4% and 6.1%, 8.1%, respectively, while 75 days after emergence, plant height and leaf number were increased by an average of 17.6%, 14.3% and 20.6%, 14.3%, respectively; film mulching could effectively control weeds. 45 days after emergence, the average plant control efficiency of BE film and PE film was 83.6% and 82.7%, respectively, while 75 days after emergence, the average plant control efficiency was 89.1% and 84.7%, and the average fresh weight control efficiency was 73.4% and 85.4%, respectively; at the same time, film mulching could also change the community structure of dominant weeds. Compared to the control, covering BE film and PE film, the average height of rapeseed plant increased by 5.6% and 5.0%, respectively, the number of primary effective branches increased by 13.2% and 22.6%, respectively, the effective pod number per plant increased by 20.6% and 22.5%, respectively, the seed number per pod increased by 30.1% and 27.5%, respectively, and the average yield increased by 55.2% and 47.5%, respectively.

Key words: film mulching, low level fertilization, rapeseed（Brassica napus L.）, weed control, yield