Year: 2001
Type: conference-abstract
Abstract: Thirteen cultivars from four species, Zinnia angustifolia Humboldt, Bonpland, & Kunth Zinnia elegans von Jacquin, Zinnia haageana Regel, Zinnia peruviana L., or hybrids of Z. angustifolia x Z. elegans, were transplanted from 0.55-L cell packs and grown in replicated landscape trials to determine growth, flowering responses, and susceptibility to Erysiphe cichoracearum and Xanthomonas campestris pv.zinniae infestation during the heat of a Central Texas summer.Zinnia elegans, Z. haageana, and Z. pauciflora exhibited more rapid early season growth and flowering propensity.Zinnia haageana, and especially Z. pauciflora, tended to be more spindly in appearance compared to the other species.A large proportion of the Zinnia elegans cultivars were infected with powdery mildew by June, while infestation with bacterial leaf spot began to occur earlier in the growing season and varied more widely in prevalence among the Z. elegans cultivars.Zinnia angustifolia was nearly immune to powdery mildew and only rarely showed symptoms of bacterial leaf blight infestation.Zinnia angustifolia also had greater flower numbers during the heat of summer than most Z. elegans taxa.While the hybrid cultivars Profusion Cherry and Profusion Orange exhibited much of the disease resistance of their Z.angustifolia parent, aesthetic limitations rather than disease or intolerance to heat were a concern.'Profusion Orange' had a rather irregular growth form.'Profusion Cherry' exhibited serious fading of the flower color by early summer.By September only the Z. angustifolia and Z. elegans x Z. angustifolia hybrid cultivars were alive.Zinnia elegans cultivars tested in this study were not suitable for use as season-long summer annuals in Central Texas due to disease and/or heat intolerance.Zinnia angustifolia cultivars appeared to perform most reliably of the species tested, but they did not grow as quickly as the Z. elegans seedlings early in the growing season.Zinnia pauciflora and Z. haageana cultivars were more disease resistant than those of Z. elegans, but had small flowers and generally less compact growth habits than the other species tested.
Source: HortScience
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: gold
Estimated APC paid: $3,000
OpenAlex ID: W4243179563