Abstract
There is now a considerable body of research, both public and industry funded, targeted at breeding varieties of various crops which perform well under reduced input systems, particularly those where reduced fertiliser and pesticide levels are employed. This research has been developed to meet national policies driven by the need for reductions in resource use while maintaining productivity. National statutory and advisory testing systems have largely been devised to identify varieties which perform well under relatively high inputs of fertilizer and pesticide. There is now an urgent need to identify criteria which can be used to evaluate material under lower input regimes. Such regimes are distinct from organic systems and must relate to mainstream production where the potential for reduced inputs is far greater. The outputs of fundamental research on the genetic basis of resource use efficiency require a level of appropriate comparative testing in order to bring benefit to the farming industry, effective knowledge transfer and to stimulate ongoing breeding effort. A recent pilot project (Defra OF0375) carried out with selected varieties of lettuce and broccoli indicated that pest and disease resistance characters were of major importance in lettuce grown under reduced pesticide inputs, but that in broccoli ability to perform under reduced nitrogen inputs was much more important. While low N significantly reduced yield and quality of some current broccoli variety material, it was clear that other varieties performed very well under low N, achieving most of the yield and quality potential seen under normal `full rate` applications. This proposal has arisen from Defra project OF0375, and aims to refine and validate the research carried out in the single season of 2008, and thus to provide the basis for evaluation systems which will promote and develop the outputs of plant breeding and plant breeding research for the benefit of resource efficient horticultural production in the UK. The research will: 1) define informative testing procedures for two different crop types, by varying key input levels 2) identify critical measures of crop productivity so that relevant genetic potential under varying inputs can be readily quantified 3) use the data generated in conjunction with existing N utilisation models to investigate the effects of variety on N losses and usage The first point will be investigated by testing lettuce and broccoli crops in commercially relevant growing regions, using a reduced input system based on 2008 experiments to allow an estimation of reproducibility of the results obtained. The second point will be addressed by including the majority of genotypes investigated in 2008, but adding further varieties in consultation with plant breeders, and evaluating characters for both their ability to describe resource efficiency, and their ease of use in future routine systems. The third point will focus on gathering additional information which will be used to populate modules in the EU Rotate N model to assess N use efficiency of varieties of the different crops examined. Plant breeders have already expressed interest in this project, and will be further consulted on material, measurements, and test systems. Breeder interest has significantly expanded from breeding varieties for organic production to include low input production, and this is reflected in many seed catalogues.
United Kingdom