BIOFERTILIZATION OF FORAGE SORGHUM TO INCREASE POLYPHENOL LEVELS FOR A POSSIBLE ANTI-METHANOGENIC EFFECT

Abstract

Methane gas is one of the main contributors to global warming, as it traps more heat than carbon dioxide in the atmosphere; livestock produce a significant percentage of this gas, so one viable alternative is to reduce methanogenesis in the rumen by providing a diet rich in polyphenols. In the present study, the increase in polyphenolic compounds in forage sorghum was evaluated, since this crop is commonly used as cattle feed. Four treatments were applied: a mixture of Bacillus sp., Azospirillum brasilense, Trichoderma, a combination of fungi and bacteria, and a control group. These treatments were tested on seven varieties of forage sorghum grown in Mexico (Canaveral, Sureno, MXSE45, Tehua, Canero, MXSE2, and MXSE19). On days 20 and 56 after planting, morphoagronomic parameters were measured (plant height, stem diameter, and photosynthetic activity), as well as the concentrations of phenols, flavonoids, and tannins. Variety MXSE19 showed the highest values for height, plant weight, and phenol concentration, with the Trichoderma treatment being the most effective variety-microorganism combination. The Tehua and Canero varieties exhibited the lowest values across all treatments. The use of biofertilizers in forage represents a potential strategy to increase the concentration of polyphenols, which have anti-methanogenic activity.