CULTURAL-STUDIES OF FUNGI CAUSING BROWN-ROT IN HEARTWOOD OF LIVING LEMON TREES IN ARIZONA

Coniophora eremophilia and Antrodia sinuosa cause brown heartrot in li ving lemon trees in southern Arizona and California. They can be disti nguished in the field by differences in rot characteristics. Both have a high optimum growth temperature of approximately 35 degrees C. Coni ophora eremophila has a cultural morphology typical of other Coniaphor a species and did not fruit in culture. Antrodia sinuosa cultures were morphologically similar to previous reports and fruited readily under laboratory conditions. Mating tests with homokaryotic single spore is olates showed it to have a heterothallic bipolar mating system. The de cay capacity of C. eremophiia on lemon wood test blocks under laborato ry conditions was low compared to that of A. sinuosa, five other brown rot fungi, and three white rot fungi.