Cedar-Apple Rust
Gymnosporangium juniperi-virginianae
Basic Details
Description
Taxonomy
Features
Translations
Basic Details
NameCedar-Apple Rust
DescriptionCedar-apple rust creates bright orange-red spots with black dots on apple leaves. Identify 'telial horns' on orange juniper galls to stop this two-host fungal cycle.
TypeFungus
FamilyGymnosporangiaceae
GenusGymnosporangium
Taxonomy & Features
PhylumBasidiomycota
SubphylumPucciniomycotina
ClassPucciniomycetes
OrderPucciniales
Features
- A complex fungal disease that requires two different hosts to complete its life cycle: a juniper/cedar and a rosaceous plant (apple, crabapple, hawthorn)
- On apple leaves, symptoms begin as tiny yellow-green spots in late spring that enlarge and turn bright orange or reddish-orange
- On the underside of the apple leaf, small thread-like structures (aecia) eventually produce spores that travel by wind back to juniper trees
- Infected fruit developed orange, slightly raised lesions that may crack, making the harvest unsightly and poor in quality
- On Junipers (especially Eastern Red Cedar), the fungus causes hard, brown, dimpled galls about the size of a golf ball
- In wet spring weather, these juniper galls swell and extrude many long, orange, gelatinous, 'telial horns' which release spores into the wind
- The disease causes premature leaf drop in apples, which weakens the tree and reduces the size and quantity of the fruit in subsequent years
- The spores can travel several kilometers by wind, but most infections occur within 1 kilometer of the juniper or apple source
- Prevent by avoiding planting apples near junipers (or vice-versa). Prune and destroy juniper galls during the dormant winter season
- Control by applying protective fungicides to apple trees during the critical 'spore release' window in early to mid-spring (bloom stage)
Names in Different Languages
Latin / ScientificGymnosporangium juniperi-virginianae
English (Alternate)Apple rust
Hindiदेवदार-सेब रतुआ (Devdar-seb ratua)
Tamilஆப்பிள் துரு நோய் (Apple thuru noy)
Teluguఆపిల్ కుంకుమ తెగులు (Apple kunkuma tegulu)
Malayalamആപ്പിൾ തുരുമ്പ് (Āppiḷ turump)
Kannadaಸೇಬು ಮರದ ತುಕ್ಕು ರೋಗ (Sēbu marada tukku rōga)
Sanskritदेवदारु-सेव-किटिभ (Devadāru-seva-kiṭibha)
Bengaliসিডার-অ্যাপেল রাস্ট (Cedar-apple rust)
Frenchrouille du genévrier
Russianржавчина яблони и можжевельника (rzhavchina yabloni i mozhzhevel'nika)
Spanishroya del cedro y del manzano
GermanBirnengitterrost (related species)
