Linkage in Linum Usitatissimum and in Melampsora Lini Between Genes Controlling Host-Pathogen Reactions

Abstract

The work of FloI', the most procise published on the genetics of disease resistance in higher plant.s, is shown to establish much less t.han is claimed. His allclie series are based on one case where linkago cannot be gl'Cater than 0·3 per cent. at 0·05 lo\'n! of certainty, if t.he data (\1'0 accepted as satisfactory: in fact, they eontain several nnsatisfactory features. For the rest of Flor's evidence, upper limits of linkages between genes within his allelic series of not less than approximately 20 per cent. are possible. More critical test·s are needed, using progeny of heterozygotes buekcrossed to a universally susceptible variety.