Brown Stain Susceptibility of Selected Lettuce Cultivars Under Controlled Atmospheres and Temperatures1,2

Abstract

Abstract Laboratory tests of 11 cultivars of crisphead type lettuce (Lactuca sativa L.) indicated all were susceptible to brown stain. Susceptibility varied among cultivars, with ‘Great Lakes 66’, ‘Calmar’, ‘Valrio’, ‘Merit’ and ‘Great Lakes R-200’ the most susceptible and ‘Greenland’, ‘Climax’ and ‘Francisco’ the least affected. Storage temperature markedly influenced brown stain incidence: lettuce held at 0°C developed more brown stain than that held at 2.5°C. Development of the disorder required that lettuce be subjected to elevated CO2 in storage. Brown stain incidence for a given cultivar varied with date of harvest and production area.