Effects of dual mulching with wheat straw and plastic film under three irrigation regimes on soil nutrients and growth of edible sunflower

Mulching is an important practice to reduce soil water loss and improve productivity in agriculture. To investigate the influence of dual mulching with crushed wheat straw padding and plastic film combined with different irrigation amounts on soil nutrients and the growth of edible sunflower, a field experiment was conducted in Minqin Experimental Station of Gansu Institute of Hydraulic Sciences from 2016 to 2018. The experiment adopted a two-factor design with four mulching methods: no mulching (N), straw mulching (S) at 4500 kg ha−1, plastic film mulching (F), crushed wheat straw padding and plastic film mulching (SF) at 4500 kg ha−1, and three irrigation levels: high (H=900 m3 ha−1), medium (M=750 m3 ha−1) and low (L=600 m3 ha−1). The results showed that the soil nutrients under the dual mulching of crushed wheat straw padding and plastic film were improved. The soil available phosphorus (AP) content was highest under SFH treatment, varying significantly with treatments (P