VEGETATIVE COMPATIBILITY AND A NEW NITRATE NONUTILIZING MUTANT PHENOTYPE IN FUSARIUM OXYSPORUM
尖孢镰孢一新硝酸盐营养突变类型与营养体亲和性

A new nitrate nonutilizing (nit)mutant phenotype,named nit 8, reflecting mutation presumptively in a structural gene for nitrate reductase was de- termined in Fusarium oxysporum isolates.In addition to nit 8,phenotypes nit 1, nit 3 and Nit M were also identified among 684 nit mutants discovered from 73 isolates of F.oxysporum and their isolation frequencies were 6.7,81.0,3.8 and 8.5%, respectively.A color indicating method in nitrite excretion tests was firstly intro- duced in such kind of studies and a new concept with a formula on complementation index (CI) was proposed to express the vegetative compatibility in pairing tests be- tween nit mutants.