Black Spot Disease
Diplocarpon rosae, Marssonina rosae
Basic Details
Description
Taxonomy
Features
Translations
Basic Details
NameBlack Spot Disease
DescriptionIdentify black spot fungal disease on roses and other plants. Learn about symptoms like circular black spots and yellowing leaves with our treatment guide.
TypeFungus
FamilyDrepanopezizaceae
GenusDiplocarpon
Taxonomy & Features
PhylumAscomycota
SubphylumPezizomycotina
ClassLeotiomycetes
OrderHelotiales
Features
- Named for the distinctive circular black spots it creates on rose leaves. One of the most widespread and serious diseases affecting roses worldwide
- Fungus appears as nearly circular black spots with fringed edges on leaf surfaces. Surrounding tissue typically turns yellow, creating a halo effect
- Overwinters on infected canes and fallen leaves. Spreads primarily by splashing water (rain or irrigation) from leaf to leaf and soil to plant
- Causes premature leaf drop (defoliation), which weakens the plant and reduces bloom quality. Severe repeat infections can kill sensitive rose varieties
- Spores require free-standing water on the leaf surface for at least 7 hours to germinate. Disease cycle from infection to new spores takes about 10-14 days
- Individual spots range from 2 mm to 12 mm (1/10 to 1/2 inch) in diameter. Often merge to cover large areas of the leaf
- Thrives in warm (24°C/75°F), humid weather with frequent rain or overhead watering. Does not spread in dry weather or temperatures over 30°C
- Primarily affects roses. Similar 'black spot' fungi affect other plants like maples and some vegetables, but the rose pathogen is highly specific
- Prevent by planting resistant varieties, ensuring full sun, spacing plants for air flow, and watering early in the morning at the plant base ONLY
- Remove and destroy all infected leaves immediately. Prune out infected canes during dormancy. Apply sulfur, copper, or neem oil sprays every 7-14 days
Names in Different Languages
Latin / ScientificDiplocarpon rosae, Marssonina rosae
English (Alternate)Rose black spot, Leaf spot disease
Hindiकाला धब्बा (Kala Dhabba)
Tamilகரும்புள்ளி (Karumpuḷḷi)
Teluguనల్ల మచ్చ (Nalla machcha)
Malayalamകറുത്ത পുള്ളি (Kaṟutta puḷḷi)
Kannadaಕಪ್ಪು ಚುಕ್ಕೆ (Kappu chukke)
Sanskritकृष्ण-बिन्दुः (Kṛṣṇa-binduḥ)
Bengaliকালো দাগ (Kalo dag)
Frenchtache noire
Russianчерная пятнистость (chernaya pyatnistost')
Spanishmancha negra
GermanSternrußtau
