Polyethylene and Biodegradable Starch-Based Mulching Films Positively Affect Winter Melon Production in Sicily

Plastic mulching is widely used in many regions of the world for growing melons. The winter melon is largely grown in the hilly countryside of the Mediterranean island of Sicily (Italy) where mulching plastic films enhance early and total yields. However, removing and disposal of polyethylene plastic mulches after use represent a major disadvantage and an environmental concern. The objective of this trial was to compare the effects of polyethylene (PE) (transparent and black) and biodegradable (black) mulching films on yield, fruit size and quality of melon grown in the open field. The trial was conducted in the north-western coast of Sicily in the province of Trapani, 250-m elevation. Melon plug plants, cv Helios, were transplanted at a density of 3 plants.m-2 on 26 May 2011. Air temperature in the soil-mulch film gap of the transparent PE was constantly higher, over a 24 h period, than the experimental treatments with the biodegradable mulch (Mater- Bi™) and the control (bare soil). Maximum soil temperatures were measured under transparent PE. Black PE film raised soil temperatures at 10 cm depth compared with Mater-Bi™ film with an increase of 0.2-2.0°C over a 24 hr period. Soil temperatures under black PE and Mater-Bi™ mulches were 2.5-3.4°C and 2.0- 3.1°C, respectively, higher than those in the bare soil between 20.00 and 7.00 HR. All mulches markedly increased early and total yields when compared with unmulched plots. Transparent PE significantly increased total marketable yields by 17% compared with black PE and Mater-Bi™. The biodegradable starch-based mulch film gave production results similar to the traditional black PE film. Its use should be considered in those situations when a black mulch colour is selected for melon production