Efficient irrigation management in sugarcane cultivation in saline soil¹

Manejo eficiente da irrigação em cultivo de cana-de-açúcar em solo salino

HIGHLIGHTS:

Biometric and production characteristics of sugarcane varieties under saline conditions were influenced by leaching fraction.

Irrigation water depths equivalent to 110 and 120% of ETc do not influence the technological quality of sugarcane varieties.

The leaching fraction using 110% of ETc increased water use efficiency to varieties SP943206 and VAT90212.

ABSTRACT

The objective of this study was to evaluate the influence of leaching fraction on the biometric and production characteristics and technological quality of the juice of sugarcane varieties grown in saline soil in the Brazilian semiarid region. The experimental design was in randomized blocks, with three repetitions, in a 2 × 3 × 3 factorial scheme, corresponding to two sugarcane cultivation cycles: plant cane and ratoon cane; three sugarcane varieties: RB72454, SP943206 and VAT90212; and, three leaching fractions of irrigation water: 0; 9.1; and 16.6%. Number of living leaves, number of internodes, leaf area, stem diameter, plant height, number of tillers, yield, total soluble solids content (°Brix), percentage of industrial fiber, juice purity, juice Pol%, cane Pol% and total recoverable sugar were evaluated. At the end of the two crop cycles, water use efficiency was determined. The varieties SP943206 and VAT90212 showed higher yield under leaching fraction of irrigation water of 9.1% in both cycles, and higher water use efficiency values were observed for the variety VAT90212. Application of leaching fractions to reduce soil salinity does not promote changes in the technological quality of the sugarcane varieties RB72454, SP943206 and VAT90212.

Key words:
Saccharum sp.; leaching fractions; salinity; technological quality; water use efficiency