播期和密度对山药零余子种苗产量与质量的影响研究

Zero residue is a pearl bud born in the axils of yam leaves, which is an important asexual propagation material of yam. In this paper, the effects of sowing date and density on the yield and quality of seedlings of different varieties were studied by using the leftovers of fine hairy yam, double-stick yam and small white-mouthed yam as materials, with 6 levels of sowing date and 4 levels of planting density, and the effects of sowing date and density on the yield and quality of seedlings of different varieties were studied. The results showed that the sowing date and planting density had significant effects on the yield of yam seedlings. The different varieties showed that the yield was highest on April 25 and decreased as the planting date was delayed. The sowing density was the highest at 130,000 plants/666.7m2, and the yield increased with the increase of sowing density. It is recommended that the most suitable sowing period of fine hairy yam, double-stick yam and small white-mouthed yam in Baoding area is from the end of April to May, and the planting density is controlled at 110,000-130,000 plants/666.7m2. The results laid the foundation for the production of high-quality seedlings.