TITLE:
Inheritance of fire blight resistance in Asian Pyrus species
AUTHORS:
Kamila L. Bokszczanin, Andrzej A. Przybyla, Malgorzata Schollenberger, Dariusz Gozdowski, Wieslaw Madry, Slawomir Odziemkowski
KEYWORDS:
“DoyennÉ Du Comice”; Asian Pear Species; Fire Blight Resistance; Pear Interspecific Hybrids; Polygenic Resistance; Monogenic Resistance; Transgression
JOURNAL NAME:
Open Journal of Genetics,
Vol.2 No.2,
June
28,
2012
ABSTRACT: Since several Asian pear species are considered to be potential source of fire blight resistance, we crossed “Doyenné du Comice”, the susceptible European cultivar, with four Asian pear species. The aim of the study was to establish the level of resistance of each genotype and the mode of transmission of fire blight resistance to each F1 full-sib progeny. The best sources of resistance were P. ussuriensis 18 and P. ussuriensis var. ovoidea 8 ranked to resistant and highly resistant, respectively. Although pear resistance to fire blight is suggested to be polygenic, distribution of phenotypes in “Doyenné du Comice” × P. ussuriensis var. ovoidea 8 hybrid family suggests the possibility of monogenic inheritance with the dominance of resistance derived from P. ussuriensis var. ovoidea 8. Polygenic inheritance of pear resistance to fire blight was identified in cross combinations of “Doyenné du Comice” with P. pyrifolia 6, and contributed by the major gene, with P. ussuriensis 18 and P. calleryana 12. Transgressive segregation was observed within the progenies of susceptible, moderately susceptible and resistant parents.