Agronomic performance of the lettuce crop subjected to different irrigation levels and soil coverings
Levels of irrigation and soil cover can affect the dynamics of soil water and directly influence the agronomic performance of lettuce crops under protected cultivation. Given this context, the objective of this study was to evaluate the influence of different levels of irrigation and types of soil coverage on the agronomic performance of the Crespa lettuce cultivar ‘Mônica’, in the municipality of Jaboticabal-SP, Brazil. The experimental design was a completely randomized block in a 3 × 3 factorial scheme with four replications. To quantify the agronomic performance of the lettuce crop, selected morphological characteristics (plant height, stem diameter, head circumference, fresh aerial parts), productivity, and water use efficiency were measured at the time of harvest. We found that uncovered soil provided the best results with respect to plant height and head circumference of the curly lettuce cultivar ‘Mônica’ in protected cultivation when treatments were raised to 100% PwC at 17 days after transplanting. The level of irrigation corresponding to 100% PwC promoted larger stem diameters, fresh aerial parts, productivity and water-use efficiency when curly lettuce is grown in uncovered soil. Increasing the maximum water storage capacity of vessels at 17 days after transplanting crisp lettuce is assumed to favorably modify the agronomic performance of the crop, thereby influencing final productivity and the efficiency of water use.