PRE-BREEDING IN EUROPE FOR QUANTITATIVE LATE BLIGHT RESISTANCE IN POTATO – A REVIEW

Abstract

In pre-breeding for quantitative late blight resistance of potato, foliage and tuber blight resistance is derived from diverse wild potato clones. Broad genetic base pre-bred clones were developed that were used as one of the resistant parental line in preferred crosses resistant x resistant. The resultant products of pre- breeding are parental lines with divergent quantitative resistance genes that are intended to improve late blight resistance in variety breeding programme. The success of pre-breeding lies in progress of re-establishment of genome of agronomic values in combination with late blight resistance achieved in minimum back crosses. Vertical distance of AUDPC to linear regression line with maturity is a correct criterion of true quantitative foliage-blight resistance in long-day condition. In this review difficulty in combination of blight resistance with early maturity under long-day conditions is discussed. Slow progress in combining of polygenic determined traits is shown. In this review breeding strategy is explained and problems and solutions are indicated. Prebreeding is a very difficult breeding task that requires in-depth skill as well as long term concept to achieve any tangible results. Saving of one third of current oomycide application is at least expected by new varieties.