(1996)  
 
The ITS sequence of the diploid P. emodi shows additivity at sites that are variable between P. lactiflora and VEI & XIN (P. veitchii or P. xinjiangensis, or their common ancestor). At site 5, however, P. emodi combines G and T, but its putative parents, P. lactiflora and VEI & XIN, have the same nucleotide, T. This may imply that the T is not the synapomorphy for P. lactiflora and VEI & XIN, but a parallelism. Hybridization between them may have occurred before the substitution from G to T occurred in one of the parents.....
the documentation of a stabilized diploid hybrid species, P. emodi which is now allopatric with its parents is particularly noteworthy.....
It is striking that after hybridization, European populations of the present Asian species were completely replaced by their hybrids. Extensive hybridization of peony species must have produced a wide spectrum of different genome combinations upon which natural selection could act. Hybrids that adapted to drastic climatic changes during Pleistocene in Europe are currently distributed in the Mediterranean region. Asian species did not survive such changes in Europe, and their distributions became more restricted. Hybrid species, P. xinjiangensis, P. emodi and P. sterniana may represent footprints of the eastern Asian species, P. lactiflora, P.veitchii, and P. mairei, when their distributional ranges became reduced to only eastern Asia. Eastern Asia was much less seriously affected by Pleistocene glaciation and may have provided refugia for these peony species....
The staminodial disk is much shorter in section Paeonia. The disk is relatively conspicuous (1-2 mm long) in P. lactiflora and P. veitchii. and their hybrid species P. emodi....
During the reduction of distributional ranges, P. lactifloraP. mairei may have become sympatric in the Himalayas and hybridized to produce P. emodi and P. sterniana....
The matK phylogeny helps identify the maternal parents of P. emodi, P. sterniana, and P. banatica, species detected as hybrids by ITS sequence additivity....
P. emodi is most closely related to P. sterniana in matK phylogenies.

(1996)  
 
Another significant biogeographic implication of detecting hybridization in section Paeonia is that the eastern Asiatic species, such as P. lactiflora, P. mairei, P. japonica and P. obovata must have had much broader distribution ranges, including the Mediterranean region where they hybridized. Their distributional ranges probably began to shrink: as they were replaced by their hybrids in the Mediterranean region during Pleistocene climatic changes in Europe..... During the reduction of distributional ranges, P. lactiflora VEI & XIN, and P. mairei may have become sympatric in the Himalayas and hybridized to produce P. emodi and P. sterniana....
For the remaining species, different accessions of each species have identical sequences. According to this straightforward alignment, the length of the intergenic spacer varies from 276 bp (P. mairei) to 318 bp (P. spontanea and P. szechuanica).....
The staminodial disk is very inconspicuous or absent in P. obovata and P. mairei.....
.....only one or two sepals of P. mairei have very small appendages......
Paeonia cambessedesii and P. russi have entire and broad leaflets which resemble those of their parent, P. mairei.....

(1996)  
 
Another significant biographic implication of detecting hybridization in section Paeonia is that the eastern Asiatic species, such as P. lactiflora, P. mairei, P. japonica and P. obovata must have had much broader distribution ranges, including the Mediterranean region where they hybridized.

(1996)  
 
Paeonia sterniana appears to combine the ITS sequences of P. lactiflora, VEI & XIN, and P. mairei; at site 12, P. sterniana has nucleotides G, T, and A which apparently came from each of these three parental sequences, respectively. At the remaining sites, additivity is seen for only two different nucleotides because two of the three putative parental sequences have the same nucleotides at these sites. This suggests that P. sterniana may have been derived from hybridization either between P. emodi and P. mairei or among the three putative parents in other orders of occurrence. It is, however, difficult to assess the mechanism of maintaining three different sequences in P. sterniana because its chromosome number is unknown......
During the reduction of distributional ranges, P. lactiflora, VEI & XIN, and P. mairei may have become sympatric in the Himalayas and hybridized to produce P. emodi and P. sterniana.....
The matK phylogeny helps identify the maternal parents of P. emodi, P. sterniana, and P. banatica, species detected as hybrids by ITS sequence additivity....
Sequences of different accessions of the same species are identical. Length of the aligned sequences vary from 372 bp (P. obovata) to 404 bp (P. sterniana) for the species sequenced....
P. emodi is most closely related to P. sterniana in matK phylogenies....
It is striking that after hybridization, European populations of the present Asian species were completely replaced by their hybrids. Extensive hybridization of peony species must have produced a wide spectrum of different genome combinations upon which natural selection could act. Hybrids that adapted to drastic climatic changes during Pleistocene in Europe are currently distributed in the Mediterranean region. Asian species did not survive such changes in Europe, and their distributions became more restricted. Hybrid species, P. xinjiangensis, P. emodi and P. sterniana may represent footprints of the eastern Asian species, P. lactiflora, P.veitchii, and P. mairei, when their distributional ranges became reduced to only eastern Asia. Eastern Asia was much less seriously affected by Pleistocene glaciation and may have provided refugia for these peony species....