91ÇÑ×Ó

Abstract

Lettuce is either sown direct to the field or as a transplant; however, both systems expose the crop to different stresses that affect uniformity and yield. A crop capable of rapid establishment could reduce these stresses and improve crop uniformity.

Description

In the US most of the lettuce (Lactuca sativa) is sown to the field directly where the seedling can be affected by thermoinhibition, weed infestation and abiotic stress such as drought, nutrient deficiency and salinity, which can have an adverse effect on yield and uniformity. To alleviate these stresses in Western Europe lettuce is often planted to the fields as an older transplant, however; transplanting can cause a broad range of mechanical and air pruning stress to the root stucture, which can lead to a varying period of transplant stresss and a resulting reduction in crop uniformity. A crop capable of rapid establishment in the field could be more robust, increasing uniformity and yield whilst allowing for a reduction in fertilizer and water application. The research will investigate the existence of a rapid establishment phenotype within a diversity fixed foundation set (DFFS) of Lactuca spp. that was developed by the Vegetable Improvement Network (VegIN) and the underlying genes involved with the trait through the use of quantitative trait loci (QTL) analysis, bioinformatics and gene expression studies before discovering if the trait presents these lines with any resistance to variable soil conditions such as drought, nutrient deficiency and salinity.

External supervisor: Professor Martin Broadley, Plant Nutrition, University of Nottingham.