Positional Cloning of a Gene for Nematode Resistance in Sugar Beet

The Hs1 pro-1 locus confers resistance to the beet cyst nematode ( Heterodera schachtii Schmidt), a major pest in the cultivation of sugar beet ( Beta vulgaris L.). The Hs1 pro-1 gene was cloned with the use of genome-specific satellite markers and chromosomal break-point analysis. Expression of the corresponding complementary DNA in a susceptible sugar beet conferred resistance to infection with the beet cyst nematode. The native Hs1 pro-1 gene, expressed in roots, encodes a 282-amino acid protein with imperfect leucine-rich repeats and a putative membrane-spanning segment, features similar to those of disease resistance genes previously cloned from higher plants.