Physiological bases of genetic gains in sugarcane yield in Argentina

•Physiological bases of genetic gains in sugarcane yield in Tucuman, Argentina.•Genetic gains for sugar yield were 0.04 and 0.14Mgha−1y−1 for plant and ratoon cane, respectively.•There was a linear increase in sugar yield, average stem weight and sugar content with the year of release of the varieties.•Sugar yield was linearly and positively related to average stem wight, sugar content and total above ground dry biomass.•The partitioning of i) total above ground dry biomass to stems or sugar, and ii) dry stem weight to sugar were not improved.