Does straw mulch alter soil evaporation, yield, and quality of sugarcane?

Cumulative soil evaporation estimation without CE(s-i) and with CE(s+i) inundation days viz. rainfall or irrigation days is an important aspect, affecting yield and quality of sugarcane, lacking in the literature. To this end, present replicated study conducted during spring 2019-2020 in irrigated sugarcane under semi-arid conditions, with differential rice straw mulch rates viz. 0, 4, 6, and 8 t ha(-1) constituting T-1, T-2, T-3,T- and T-4 treatments, respectively. Attempts being made to delineate CE(s-i), CE(s+i) for which mini-lysimeters and pan evaporation (Ep) data used, respectively, and their effect on yield and quality parameters of sugarcane. From tillering to grand growth stage, CE(s-i) from T-1 reduced to 2.4, 9.7, and 26.5% in T-2, T-3,T- and T-4 plots, respectively whereas 7.14 and 15.3% reductions recorded while shifting from T-2 to T-3 and T-3 to T-4 plots. However, CE(s+i) reduced to 1.4, 14.4, and 5.6% while shifting from T-1 to T-2, T-2 to T-3,T- and T-3 to T-4 plots. Periodic growth parameters viz. cane height, width, Brix, and relative leaf water contents reported to improve but non-significantly in T-2, T-3,T- and T-4 plots as compared to T-1 plots. Averaged SPAD readings were reported to 7.6, 14.9, and 17% higher at 311 DAS in T-2, T-3 and T-4 plots, compared to T-1 plots. T-3 plots reported significantly higher cane yields and commercial cane sugar (t ha(-1)) than T-1 and T-2 plots but at par with T-4 plots. Therefore, T-3 plots loaded with 6 t ha(-1) of mulch reported to reduce CE(s-i), CE(s+i), and improve cane yield, and quality.