Fecha de publicación: -- Fuente: WIPO "tomato" The present invention relates to the technical fields of gene segregation and plant improvement, and in particular to a late blight resistance gene, a biomaterial, and a use. An Rpi-caj1 nucleic acid molecule comprises: a nucleotide sequence as shown in any one of SEQ ID NOs: 1-6; a nucleotide sequence encoding the amino acid sequence shown in any one of SEQ ID NOs: 7-12; a nucleotide sequence shown in any one of SEQ ID NOs: 13-18; and a nucleotide sequence having at least 75% sequence identity with the described nucleotide sequences. An important gene resource is provided for late blight resistance breeding of potatoes, thereby solving the problem of loss of disease resistance of potato varieties and providing a new guarantee for persistent disease resistance of potatoes.