Development of RL Plus: winter wheat variety performance in relation to site characteristics


Cereals & Oilseeds
Project code:
01 June 2002 - 31 December 2005
AHDB Cereals & Oilseeds.
AHDB sector cost:
£120,898 from the Home-Grown Cereals Authority (Project 2698)
Project leader:
S. Welham, Rothamsted Research, Harpenden, Herts. AL5 2JQ



About this project


This project developed RL Plus, an augmented version of the Recommended Lists for Cereals and Oilseeds, published by the HGCA on CD and the internet ( to provide the cereals and oilseeds industry with means of interrogating and analysing data from HGCA-funded variety trials.  Given that RL Plus is fully documented and published in electronic form, it is not described further here.  This report is confined to additional research analysing relative variety performance of winter wheat in terms of site characteristics.

A spreadsheet was constructed of treated yields of winter wheat from 43 varieties across 506 trials (Recommended List, National List or BSPB trials) in the UK from harvests during 1992-2002.  This included site information collected from the trials, and supplemented with the site location (OS co-ordinates), soil types, meteorological data and drought index derived during the project.  Complete, or near-complete, data existed for 249 trials from harvests during 1993-2003. These data were used to investigate factors associated with site variation in variety yields.