[Effects of planting density on yield and quality of Chrysanthemum morifolium]

In this paper, five field density treatments were set up in the field plot experiment, which were 2 500,3 000,5 000,6 660,8 000 plants/mu(1 mu≈667 m~2). The agronomic traits, economic traits, mineral element absorption and the content of effective components of Chrysanthemum morifolium under different densities were studied. The results showed that dense planting could significantly reduce the number of secondary branches of Ch. morifolium and the yield per plant, but significantly increase the population yield of Ch. morifolium. The yield of Ch. morifolium was the highest when the density was 8 000 plants/mu, but the effect of increasing yield would gradually decrease with the increase of planting density. With the increase of planting density, the N, P and Mg elements in flowers firstly increased and then decreased. The N element content in leaves increased gradually, which showed that increasing the planting density within a certain range could increase the absorption of N, P and Mg elements in flowers and leaves of Ch. morifolium. The contents of rutin, chlorogenic acid and 3,5-O-dicaffeoyl quinic acid in Ch. morifolium showed a trend of first increasing and then decreasing with the increase of planting density. When the planting density was 5 500,5 000,3 750 plants/mu, the content of chlorogenic acid, rutin and 3,5-O-dicaffeyl quinic acid had the maximum value. The content of luteolin in Ch. morifolium decreased gradually with the increase of planting density. When the planting density was 7 143 plants/mu, the content of luteolin was the minimum. Considering factors such as yield and active ingredient content, the cultivation density of 5 000 plants/mu(row spacing 40 cm×30 cm) can be selected for standard planting of Ch. morifolium.