With a circular economy, biodegradable waste – plant biomass can be reused as: compost, for soil fertilization, and for biogas production, as an affordable bioenergy source. In this study, the productivity of two hybrids of fodder sorghum, grown in Ilandza, Serbia, was examined. The results showed that there was a statistically significant difference between the tested hybrids, for leaf mass. A positive highly significant correlation was found between plant mass and leaf mass. Fodder sorghum is a species with C4 photosynthesis, which has a high degree of photosynthetic activity and has a high production of organic matter resulting in high biomass yield. Sorghum is a productive and cost-effective plant suitable for production: animal feed, and for energy purposes.Cirkularnom ekonomijom, biorazgradivi otpad-biomasa biljaka može se koristiti i kao: kompost ali i za proizvodnju biogasa, kao pristupačan izvor bioenergije. U ovoj studiji ispitivana je produktivnost dva hibrida krmnog sirka, gajenog u Ilandži u Srbiji. Rezultati su pokazali da postoji statistički značajna razlika između testiranih hibrida. Pronađena je pozitivna značajna korelacija između mase biljke i mase lista. Krmni sirak je vrsta sa S4 fotosintezom, ima visok stepen fotosintetske aktivnosti i visoku proizvodnju organske materije što rezultira visokim prinosom biomase. Produktivna je vrsta pogodna za proizvodnju: hrane za životinje i energetske svrhe
