Ana COJOCARIU
“Anastasie Fatu” Botanical Garden, “Alexandru
Ioan Cuza” University of Iasi, Dumbrava Rosie Street, no.
7-9, 700487 Iasi – Romania
Romanian Academy, Commission for the Protection of Natural Monuments,
125 Calea Victoriei, Sector 1, 010071 Bucuresti - Romania
Alina Elena CRÎŞMARU
“Anastasie Fatu” Botanical Garden, “Alexandru
Ioan Cuza” University of Iasi, Dumbrava Rosie Street, no.
7-9, 700487 Iasi – Romania
https://doi.org/10.47743/jpd.2025.32.1.986
Keywords: chrysanthemum horticultural varieties,
disease management, Puccinia horiana, resistance, white
rust.
Abstract: Chrysanthemum white rust (CWR), caused
by Puccinia horiana Henn., is a quarantine disease that
poses a serious threat to chrysanthemum production under protected
cultivation. This study aimed to evaluate the incidence, severity,
and cultivar-specific responses to CWR in a greenhouse collection
of Chrysanthemum × grandiflorum Ramat.
at the “Anastasie Fatu” Botanical Garden of Ia?i,
Romania. A total of 35 cultivars (1,120 plants) were monitored
under uniform greenhouse conditions between 2020 and 2023 growing
seasons. Disease assessment was based on systematic visual inspections,
microscopic confirmation of the pathogen, and quantitative evaluation
using Disease Incidence, Disease Severity Index, and standardized
Combined Score integrating both parameters. Cultivars were classified
into susceptibility categories ranging from tolerant to highly
susceptible. In 2020, disease incidence ranged from 0% in resistant
cultivars to over 90% in highly susceptible ones, with corresponding
variations in disease severity. The implementation of integrated
management strategies, including cultural practices, curative
fungicide applications at 13 and 15 weeks after planting, and
preventive treatments at 5 weeks after planting, resulted in a
significant reduction in disease incidence and severity in 2021.
Continuous monitoring combined with preventive treatments in 2022
and 2023 led to the complete suppression of CWR, with no visible
symptoms observed across all cultivars. Several cultivars consistently
exhibited resistance throughout the study, while others showed
high susceptibility under initial disease pressure. The findings
demonstrate that the integration of resistant cultivars with early
preventive measures and continuous monitoring is essential for
the sustainable management of P. horiana in greenhouse
chrysanthemum production. This study provides a practical framework
for disease assessment and supports informed cultivar selection
and integrated disease control strategies for ornamental crops.
How to cite this article:
COJOCARIU A. & CRÎŞMARU A. E. 2025. Assessment
and sustainable control of white rust (Puccinia horiana
Henn.) in the Chrysanthemum cultivars collection of the
Iasi Botanical Garden (Romania). J. Plant Develop. 32:
27-41.
https://doi.org/10.47743/jpd.2025.32.1.986
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