In order to provide a theoretical basis for high-quality

high-yield

and high-efficiency planting of edible sunflower in the cold-cool irrigation area of Hexi Oasis

a field trial of edible sunflower with drip irrigation deficit adjustment under film mulch was conducted in 2019

Zhangye City Yimin Irrigation Experimental Station to explore the influence of adequate irrigation at the bud

flowering

and grouting stages treatment

the seedling stage (mild) — maturity stage (mild and Moderate) water deficit treatment

the seedling stage (moderate) — maturity stage (mild and moderate) water deficit treatment

and the seedling stage (severe) — maturity stage (mild and moderate) water deficit treatment on water consumption

photosynthesis

quality

and yield of edible sunflower. The results showed that: (1) The water consumption

water consumption modulus

and daily water consumption intensity of edible sunflowers at the seedling stage and the mature stage decrease with the increase of water deficit. Compared with full irrigation

the water consumption

water modulus

and daily water intensity in the seedling stage decreased by 10.10%~46.08%

7.57%~34.58%

10.68%~46.60%

and in the maturing stage decreased by 5.50%~30.29%

2.93%~16.72%

5.56%~30.34%. The compensation effect of severe water regulation deficit during the later period was limited. (2) Severe water deficit at seedling stage and moderate water deficit at maturity stage significantly reduced net photosynthetic rate

stomatal conductance

and transpiration rate of edible sunflower leaves. Compared with full irrigation

the declines of severe water deficit adjustment at seedling stage were 40.30%~45.98%

43.99%~47.37%

38.20%~42.10%

the declines of moderate water deficit adjustment at maturing stage were 14.23%~32.07%

15.98%~51.23%

10.02%~28.45%.(3) The quality of mild water deficit in seedling stage—moderate water deficit in maturing stage was the best

and its crude fat content and crude protein content were 10.84% and 14.90% higher than those of full irrigation. (4) The yield of mild water deficit in seedling stage—moderate water deficit in maturing stage was 4145 kg/hm2

which is at the same level as the control CK. The yield was not significantly reduced. The treatment had the function of saving water and regulating quality. Taking indicators such as water consumption

photosynthetic characteristics and quality of edible sunflowers into account

under the conditions of full irrigation in other growth periods

moderate water deficit adjustment at the seedling stage and mild mature stage was adopted as the optimal water-saving deficit irrigation mode for local sunflowers.