LINKAGE ANALYSIS OF 10 ISOZYME GENES IN F1 SEGREGATING ALMOND PROGENIES

Ten isozyme genes were studied after analyzing the variability of eigh t enzyme systems- glucose phosphate isomerase (GPI), phosphoglucomutas e (PGM), aspartate aminotransferase (AAT), leucine aminopeptidase (LAP ), 6-phosphogluconate dehydrogenase (6PGD), isocitrate dehydrogenase ( IDH), shikimate dehydrogenase (SDH), and aconitase (ACO)-in the progen y of five crosses among almond [Prunus amygdalus Batsch, syn. P. dulci s (Miller) D. A. Webb] cultivars. Six of these loci were found to be l ocated in two linkage groups, one containing four loci (Pgm-2, Gpi-2, Aat-2, and Lap-1) and two more in the other (Idh-2 and Aat-1). Genetic configurations of pairs of loci specific to segregating F-1 progeny o f crosses between heterozygous parents were found in our data, for whi ch we derived the estimate of the recombination fraction and its varia nce. Linkage data for the gene pairs that could be estimated in variou s crosses were used to obtain a joint estimation of the recombination fraction.