Effect of shading net and floating row covers in winter lettuce (Lactuca sativa) crops

Abstract

Lettuce is considered the most consumed vegetable in the country which grows throughout the year. The aim of this work was to evaluate the effect of the shading net and floating row covers on the yield and leaf appearance in winter lettuce. The trial was carried out in EEA INTA Colonia Benítez, Chaco on Argiudol oxic soil. The crop was cultivated under three different conditions, 50% shade net, floating row covers and in open sky. The sowing date was on 06/06/2012 using the cv. Grand Rapid and distances of 0.40 m between rows and 0.25 m between plants. The harvesting and yield determination were at 77 DAS. In each situation, soil temperature and PAR were measured.  The results showed the highest yields in open sky, followed by floating row covers and the lowest yield in shadde net 50%. The average PAR was higher in open sky conditions, followed by floating row covers and 50% shade net, while  soil temperature showed values within the optimal range for cultivation in the three treatments being higher in the floating row covers one. These results evidenced that the use of 50% shade net reduced the yield in winter conditions in Colonia Benítez (Chaco),  which was not the case of floating row covers.