Open Access
Differential Response to Foliar Infection with Botrytis cinerea within the Genus Pelargonium
Author(s) -
Michael S. Uchneat,
Angelica Zhigilei,
Robert J. Craig
Publication year - 1999
Publication title -
journal of the american society for horticultural science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.408
H-Index - 80
eISSN - 2327-9788
pISSN - 0003-1062
DOI - 10.21273/jashs.124.1.76
Subject(s) - biology , cultivar , ploidy , botrytis cinerea , botany , genotype , horticulture , resistance (ecology) , agronomy , gene , genetics
Foliar evaluations for Botrytis resistance of greenhouse grown plants were performed on 45 cultivars and control genotypes including diploid and tetraploid zonal ( P. × hortorum L.H. Bailey) and ivy ( P. peltatum (L.) L'Hér. in Ait.) pelargoniums. Additional evaluations were performed on eight species within section Ciconium and on progeny of a susceptible by susceptible cross-pollination involving the cultivars Ben Franklin and Marilyn. Differential levels of resistance were observed. Among many genotypes that exhibited resistance, two genotypes had consistently high levels of Botrytis resistance over several experiments. These two genotypes were the diploid P. peltatum accession 86-23-1 and the tetraploid P. × hortorum cultivar Fox. The diploid P. × hortorum cultivar Ben Franklin was a reliable susceptible control in all experiments. Plants grown outdoors generally had higher levels of resistance than comparable greenhouse grown plants. Orthogonal contrasts indicated no trends in resistance when comparing diploid and tetraploid pelargoniums, or when comparing among ivy, zonal, and floribunda types. Genotypes patented or introduced since 1990 have greater susceptibility than older genotypes. Cross-pollinations among susceptible parents resulted in susceptible progeny, while self-pollinations of a resistant parent resulted in resistant progeny.