Fabrication of a straw-based degradable mulch film with magnetically controlled-release glyphosate

To solve three main problems in agriculture (plastic mulch pollution, difficult straw recycling, and low utilization efficiency of pesticides), a multifunctional mulch film (MF) was fabricated. In this study, corn straw was mixed with xanthan gum, glyphosate (Gly), Fe3O4, and MIL-100(Fe) to obtain a MF named as SMFG with magnetically controlled-release Gly. To improve the hydrophobicity and stability of SMFG, the surface was coated by amino silicone oil (ASO) to get SMFG@ASO. SMFG@ASO had well insulation and moisture retention properties close to polyethylene MF. Meanwhile, the weight loss ratio of SMFG@ASO increased with time and could reach 59% underground in 120 d, indicating the good biodegradation behavior of SMFG@ASO. Importantly, pot experiment showed that SMFG@ASO could significantly promote growth of crop and inhibit grass. Besides, earthworm experiment illustrated that SMFG@ASO possessed a high biosafety and could increase the relative abundance of beneficial bacteria (Flavobacterium) from 0.08 to 0.21 and soil quality. Thus, this study provides a new method to prepare a straw-based degradable MF for resolving the problems of plastic pollution and waste of straw resources simultaneously to realize the integration of herbicide and MF.