Genetic characterization of new varieties and hybrids of citrus table fruit through isoenzymes
Roberto Pedroso de Oliveira and Elizete Beatriz Radmann
The aim of this study was to establish isoenzymatic patterns to genetically characterize the orange varieties ‘Lane Late’, ‘Navalete’, ‘Navelina’ and ‘Salustiana’, mandarin varieties ‘Clemenules’, ‘Marisol’ and ‘Satsuma Okitsu’, and the hybrids ‘Nova’ and ‘Ortanique’. The following isoenzymatic systems were utilized: alcohol dehydrogenase (ADH), esterase (EST), acid phosphatase (APS), phosphoglucoisomerase (PGI), phosphoglucomutase (PGM), 6-phosphogluconate dehydrogenase (6-PGDH), glutamate oxaloacetate transaminase (GOT), isocitrate dehydrogenase (IDH), leucine aminopeptidase (LAP), malate dehydrogenase (MDH), peroxidase (PRX), sorbitol dehydrogenase (SDH), superoxidase dismutase (SOD) and shikimate dehydrogenase (SKDH). Proteins were extracted from leaves and the isoenzymatic polymorphisms were analyzed by polyacrylamide gel electrophoresis. The PGM isoenzyme showed the highest differentiation among the genetic materials tested. The banding profiles observed for PGM, SKDH and EST were satisfactory to characterize the mandarin varieties and hybrids studied. However, no polymorphic bands were found in sweet oranges with the 14 isoenzymes tested.