Identifying crisphead lettuce genotypes for a wider range of environments

Abstract

This work aims to select crisphead lettuce (Lactuca sativaL) genotypes superior in production, stability, and adaptability using a mixed model method: restricted maximumlikelihood/best linear unbiased prediction.Ten genotypes were grown in different municipalities of the State of São Paulo, Brazil, and seasons of the year, resulting in twelve different environments. The experiment has a randomized complete block design with four repetitions. Genotypes comprise eight breeding lines and two commercial cultivars, Vanda and Vera. The evaluated traits include total production in g/plant, commercial production in g/plant, and numbers of leaves/plant. Analysis of joint deviance indicated that the genotypes responded differently to the environments evaluated. The crisphead lettuce breeding lines that were most productive, stable, and adapted to the twelve lettuce-growing environments, even outperforming the commercial Vanda and Vera cultivars, were lines L8, L2,and L6.

Keywords

• genotype-environment interaction
• genotypic values
• lactuca sativa
• reml/blup
• stability and adaptability