百香果及相關種之Peroxidase及Glutamate Oxaloacetate Transaminase同功異構酶的變異性與遺傳分析

Abstract

Zymograms of peroxidase (PRX) isozymeo in 10 Passifiora species each display one unique dense PRX-2 band characterized by accompanying a series of shadow bands. Eight types of PRX-2 allozymes were distinguishable among species. Yellow passion fruit revealed as F type Rp 0.42 in all six accessions and S type Rp 0.35 wan found in purple passion fruit, these altered allozymes were analyzed through progeny testing proved to be controlled by single locus assignated as Prx-2 gene. The Prx-2 alleles express codominance and pronounced allelic dosage effect. Quantitative expressivity of both F and S alleles increased as leaf development, and remained persistent through the maturation in either homozygote or heterozygote. The relative activity of F allele was a little higher than S allele. The polymorphic Prx-2 genes could be used as prominent genetic markers for species or hybrid identification. High variation in band number, relative intensity and mobility of GOT inozymes were observed in Passiflora species. The GOT band clusters of interspecies could be classified into Ⅰ, Ⅱ and intermediate groups. Selfing progeny of purple or yellow passion fruits showed monomorphic multiple bands identical to parent respectively. The phenotypic expression of interspecific or intraspecific hybrids was also respectively exhibited one uniform cluster likely derived from the additivity of both parental band clusters. The characters of codominance, dosage effect and one nonparental band were noticed. Two types of parental band cluster and one additively hybrid banding pattern were recovered in F population. Proposed genetic hypothesis is the multiple bands of GO isozymes encoded by Got-X locus which is composed of more than 8 genes in group Ⅰ species and additionally three genes specified the slower migrating in the group Ⅱ. Each species possess 4-6 active genes and the others are low activity or null alleles. The compound linked genes inherited as one genetic unit. Linked duplication conducted to fixed heterozygosity,