Seedlings froco two clones of M. arvensis L var. piperascens Malinvaud were selected by olfative test to eliminate the plants with high pulegone content in the essencial oil; the selected plants were inoculated with spore suspension of Puccinia menthae Pers., and classified in three classes of susceptibility. The blooming plants were distilled and the obtained samples of essential oil were analysed by gas chromatography to verify its menthol, menthone and pulegone contents. The data showed that the studied material presents high variability to rust resistance and menthol content in its essencial oil. Eight progenies from Valinhos clone presented high rust resistance, 75.80% to 85.18% menthol and 0.48 to 1.36% pulegone content; two progenies froco Samby clone presented high rust resistance, 77.12 to 83.74% menthol and 0.94 to 2.05% pulegone contents. Three progenies from Valinhos and two from Samby clones presented low menthol contents from 54.26 to 64.93%, similar to the dementholized oil from M. arvensis.
Mentha amensis L. var. piperascens Malinvaud; disease; breeding