A Comparison of Tipburn Susceptibility in Lettuce Under Field and Glasshouse Conditions

Abstract

SummaryEight lettuce cultivars have been tested for susceptibility to tipburn in the field on seven occasions during 1973 and 1974. Four of these cultivars, Borough Wonder, Cobham Green, Improved Lobjoits Green and Avon Crisp were badly affected by tipburn, whilst Avon Defiance, Great Lakes 659, Little Gem and Webbs Wonderful were virtually free of the disorder.A method for inducing tipburn in young plants in the glasshouse is described, but it is shown that only Great Lakes 659 and Borough Wonder responded similarly under both glasshouse and field conditions. Tipburn susceptibility in the other cultivars, as determined in young plants under glasshouse conditions, is not necessarily matched by a corresponding susceptibility in the field and, until the factors responsible for this discrepancy have been identified, glasshouse screening is unlikely to be useful for breeding purposes. The only immediate practical solution to the tipburn problem would appear to be to sow only those cultivars that have been sho...