Avaliação do efeito de diferentes plantas de cobertura de solo sobre o desempenho agronômico de alface (Lactuca sativa) americana cv. tainá ® e crespa cv. crocante ®

Abstract

This study aimed to evaluate the performance of lettuce cultivars (Lactuca sativa L.) Tainá ® (American style) and Crocante ® (crisped type) on cover crops consist of peanut (Arachis pintoi), sorgo (Sorghum bicolor) lablab (Lablab purpureus), summer oats (Sorghum sudanense), raw and cassava leaves (Manihot esculenta) and control (no cover) in organic farming in the fall. The study was conducted in Sítio São José, Laranjeiras do Sul - PR. The experimental design was a randomized complete block in a factorial design with six replications. The parameters evaluated in lettuce cultivars were root length (RL), head diameter (HD), fresh pasta shoot (FPS), dry mass of shoots (DMS) and soil moisture content provided by each cover. Soil analyzes were performed at baseline and at the end of the experiment, just to check the chemical condition of the soil. The data of the evaluated parameters (RL, HD, FPS and DMS) were collected after the passage fifty days after transplanting. After thirty-five days of the transplanting soil samples were taken to check the moisture content. Data were collected and analyzed with the ASSISTAT statistical analysis program. In general, most of the evaluated parameters was a best result of growing Crocante ® compared to Tainá ®. FPS for the raw coverage and cassava leaves showed superior results to other treatments, the covers were higher in FPS buildup from the ground without cover. In Tainá ® covers provided higher accumulation of DMS and HD when compared to control, with the exception of summer oatmeal with coverage that presented results similar to witness. The covers provided greater HD in cultivating Crocante ® compared to control, also provided greater accumulation of moisture to the soil compared to control, except for sorgo. This work demonstrates the importance of ground cover for lettuce cultivation system, and cover with raw and cassava leaves excelled in FPS buildup. The work also showed a better agronomic performance of the plant variety Crocante ® compared to Tainá ®.