Assessment of factors influencing the biomethane yield of maize silages

•Biomethane yield per hectare of maize silages was assessed.•The cropping environment is the most influential factor for the biomethane yield per hectare.•Late maturing maize varieties harvested at an early stage are advised for biomethanation.•Volatile solids can predict the biochemical methane potential of maize silages.

A large set of maize silage samples was produced to assess the major traits influencing the biomethane production of this crop. The biomass yield, the volatile solids contents and the biochemical methane potential (BMP) were measured to calculate the biomethane yield per hectare (average = 7266 m3 ha−1). The most influential factor controlling the biomethane yield was the cropping environment. The biomass yield had more impact than the anaerobic digestibility. Nevertheless, the anaerobic digestibility of maize silages was negatively affected by high VS content in mature maize. Late maturing maize varieties produced high biomass yield with high digestibility resulting in high biomethane yield per hectare. The BMP was predicted with good accuracy using solely the VS content.