USE OF GLUTAMATE-OXALOACETATE TRANSAMINASE ISOZYMES FOR DETECTION OF HYBRIDS AMONG GENERA OF THE TRUE CITRUS-FRUIT TREES

Intergeneric hybrids between Microcitrus (Microcitrus inodora) x Eremo citrus (Eremocitrus glauca), Microcitrus (Microcitrus warburgiana) X F ortunella (Fortunella margarita), Fortunella (F. margarita) X Microcit rus (M. warburgiana), and Citrus (Citrus grandis cultivar 'Tosa-buntan ') X Poncirus (Poncirus trifoliata) were developed by controlled polli nation. Hybridization was confirmed by isozyme analysis using polyacry lamide gel electrophoresis. Genetic analysis of glutamate-oxaloacetate transaminase (GOT) clearly indicated that a dimeric nature of GOT iso zymes in 'true citrus fruit trees' of the subtribe 'Citrinae' and thei r genetic control by two loci with six alleles at Got-1 and four allel es at Got-2. Four new species-specific alleles were discovered, one fo r E. glauca (Got-1 'E') and three for M. warburgiana (Got-1 'W', Got-2 'W' and 'G'). Common alleles were observed among the genera of Microc itrus, Fortunella and Eremocitrus and homologous loci were observed am ong the studied genera.