Abstract: Two\|factor experiment with different nitrogen dosage and planting density were studied to provide further evidence for effect of nitrogen dosage and planting density on the yield and commercial quality of autumn broccoli. The results showed that the days from field planting to squaring of high density planting and less nitrogen treatment were significantly less than that of spaced planting and more nitrogen treatment. The diameter of flower bud significantly decreased in the treatments of middle or high planting density and nitrogen dosage. The broccoli unit yield increased under high planting density and nitrogen dosage treatment. Furthermore, it was beneficial to improving the pass rate of fresh broccoli under the middle level of planting density and nitrogen dosage, and the pass rate significantly decreased under the low level of planting density and nitrogen dosage. According to the field conditions, the planting density should be 2 500-2 800 plants per 666.7m² and pure nitrogen dosage should be 25-40 kg per 666.7m² in consideration of high quality, high yield, high effect, and fresh export. In the condition of middle or high fertility, the lower range of plant density and nitrogen dosage was more suitable.

Key words: broccoli (Brassica oleracea L. var. italica Planch), planting density, nitrogen dosage, yield, commercial quality