Fuente: WIPO "tobacco agriculture" The invention discloses a tobacco NtIAA27 gene mutant, and a molecular identification method and application. The tobacco NtIAA27 gene mutant is Ntiaa27-1; G at the 576th site of a tobacco NtIAA27 gene is mutated into A to form a termination codon, so that the gene is terminated in advance; and the nucleotide sequence of the tobacco NtIAA27 gene mutant is shown as SEQ ID No.1. After the gene of the tobacco NtIAA27 gene mutant Ntiaa27-1 in the invention is mutated, the nicotine content of tobacco can be obviously increased; the tobacco quality is remarkably improved; and the tobacco NtIAA27 gene mutant Ntiaa27-1 has great value in tobacco breeding.