Resumen
- Studies of sugarcane varieties grown under water-restrictive conditions are necessary because climate changes may result in insufficient rain for agriculture and selecting or breeding drought-tolerant cultivars will become more and more important. This study aimed to quantify the accumulation and partitioning of biomass, as well as water use efficiency of commercial sugarcane varieties under different soil water availability conditions throughout the growing season. The study was conducted during two cropping cycles in Southeast Brazil (22.7 °S, 47.6 °W). Four soil moisture availability regimens were set up to provide 100, 75, 75* and 50% of the water demand of eight commercial varieties of sugarcane (CTC15, CTC17, RB867515, RB92579, RB931011, RB966928, IAC5000, and NCo376). The total aboveground biomass was measured in both crop cycles. Our results indicate that two Brazilian varieties (CTC15 and CTC17) and one South African variety (NCo376 - Canegrow DSSAT reference), increased their water use efficiency when grown under an irrigation deficit of 75% of normal, without yielding less biomass.