Differential organellar inheritance in Passiflora's (Passifloraceae) subgenera.

Four chloroplast (cp), one mitochondrial (mt), and one ribosomal nuclear (ITS) DNA regions were studied in four artificial and one natural interspecific Passiflora hybrids. The ITS results confirmed their hybrid origin and all mtDNAs were maternally inherited. The same, however, was not true for cpDNA. The four hybrids (three artificial and one natural) derived from species of the Passiflora subgenus showed a cpDNA paternal inheritance, while the one involving taxa of the Decaloba subgenus gave evidence of maternal transmission. These results are of significance for the ongoing studies which are being performed on the molecular evolution of this genus and furnish important background for investigations aimed at clarifying the factors which determine cpDNA inheritance.