Function Identification Of Biz1Induced Genes In Ustilago Maydis

Maize is an important grain crops, feed crops and raw materials for industry, whichholds the important status in our country’s agricultural production and the nationaleconomy development. Corn smut, one kind of worldwide plant disease, can affectthe maize yield and quality. Therefore it is very important to investigate this disease inmore details. Recent results indicate that the biz1gene deletion mutant can not infectthe corn any more. So we speculate the pathogenic development of Ustilago maydisafter plant penetration is regulated by Biz1. During the pathogenic growth process ofUstilago maydis, bip genes（Biz1induced protein）are up-regulated by the Biz1protein, therefore these genes may involve in the pathogenic development of Ustilagomaydis after plant infection.In this work, some candidates of bip genes are selected for the over expression anddeletion to identify their functions by plant infection experiments. Symptoms aftermaize infection were compared during these mutant strains to find out the function ofthese genes. The results can provide the theory basis for corn smut prevention andcure.The plant infection experiment showed that the maize had more severe incidenceafter infection by the srp1deletion mutants, the size and number of tumors had anobvious growth compared with the wild-type strains; the srp1over expressionmutants reduced the incidence, the size and number of tumors had an obviousdecrease compared with the wild-type strains. Taken together, the expression of srp1gene can suppress the pathogenic development of Ustilago maydis after plantinfection.