The role of big films: 1, big films can be used as soil fungicides. 2, big films can improve the soil. 3, big films have a strong penetration and adhesion, can provide fertilizer for crop nutrients long. 4, big films can improve disease resistance of crops, nematodes and other pests have a strong inhibitory effect. 5, big films can promote the growth of plant roots. 6, big films can increase the permeability of pesticides, helps to reduce the use of pesticides. Source: http: //www.jhdpnm.com/