探究重茬次数及种植密度对切花向日葵品质和经济效益的影响，得到最优化重茬和密度种植模式，使切花向日葵单位面积经济效益最大化，为河西灌区切花向日葵种植提供依据。以切花向日葵文森特2号为供试材料，采取裂区设计，主区重茬次数设0、1、2次3个水平，副区种植密度设133 400、100 000、80 000、66 600、57 200株/hm2 5个水平，探究了重茬次数和种植密度对切花向日葵物候期、农艺性状、瓶插期、商品切花产出率以及经济效益的影响。结果表明，随着重茬次数的增加，显著缩短了切花向日葵的生育期和观花期，降低了平均株高、茎粗、叶片大小、舌状花直径和花序直径等农艺性状，导致商品切花产出率显著下降；随着种植密度降低，缓解了重茬对向日葵生长的负面影响，提高了茎粗、花序直径和商品切花产出率。瓶插期不受重茬和密度影响。经济效益受重茬次数和种植密度的影响明显，无重茬时，推荐高密度(133 400株/hm2)种植，净收益可达到235 907.9元/hm2；重茬1次时，推荐中等密度(100 000株/hm2)种植，净收益可达到160 733.3元/hm2；重茬2次时，推荐中等偏低密度(80 000株/hm2)种植，净收益可达到59 586.7元/hm2，可实现净收益最大化。

By studying the effects of consecutive cropping times and planting density on the quality and economic benefits of cut sunflowers, we aim to obtain the optimal consecutive cropping and density planting pattern, thereby maximizing the economic benefits per unit area of cut sunflowers, and providing a basis for the cultivation of cut sunflowers in the Hexi irrigation district. Using the cut sunflower variety Vincent 2 as the test material, a split-plot design was adopted. The main plot factor was continuous cropping frequency: 0 times, 1 time, and 2 times. The subplot factor was planting density: 133 400 plants/ha, 100 000 plants/ha, 80 000 plants/ha, 66 600 plants/ha and 57 200 plants/ha. The effects of continuous cropping frequency and planting density on the phenological period, agronomic traits, vase life, marketable cut flower yield rate, and economic benefits of cut sunflowers were explored. Results showed that an increase in continuous cropping frequency significantly shortened the growth period and ornamental flowering period of cut sunflowers, reduced agronomic trait indicators such as plant height, stem diameter, leaf size, ray floret diameter, and inflorescence diameter, and led to a significant decrease in the marketable cut flower yield rate. Reducing planting density alleviated the negative effects of continuous cropping on sunflower growth, improving stem diameter, inflorescence diameter, and marketable cut flower yield rate. Vase life was not affected by continuous cropping or density. Economic benefits were jointly influenced by continuous cropping and density. For no continuous cropping, high-density planting(133 400 plants/ha) was recommended, for one time of continuous cropping, medium-density planting (100 000 plants/ha) was recommended, and for 2 times of continuous cropping, medium-to-low density planting(80 000 plants/ha) was recommended to maximize net income, which could achieve the maximum net returns of 235 907.9 Yuan/ha, 160 733.3 Yuan/ha, and 59 586.7 Yuan/ha, respectively.

S565.5

甘肃省农业科学院科研条件建设及成果转化中青年基金项目(2023GAAS31)。