Chrysomyxa ledi var. rhododendri
Encyclopedia
Chrysomyxa ledi var. rhododendri is a plant pathogen responsible for the disease spruce needle rust.
It is present in Europe
an mountains, and especially in Switzerland
in Grisons and Ticino
between 1,000 and 2,000 metres.
The spore
s of the fungus hibernate on Rhododendron
species. In spring
and summer
, it migrates to spruce
and infects recently emerged needles, coloring them in yellow
. In autumn, the spores that developed on spruce infects the rhododendron again.
It is present in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
an mountains, and especially in Switzerland
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
in Grisons and Ticino
Ticino
Canton Ticino or Ticino is the southernmost canton of Switzerland. Named after the Ticino river, it is the only canton in which Italian is the sole official language...
between 1,000 and 2,000 metres.
The spore
Spore
In biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions. Spores form part of the life cycles of many bacteria, plants, algae, fungi and some protozoa. According to scientist Dr...
s of the fungus hibernate on Rhododendron
Rhododendron
Rhododendron is a genus of over 1 000 species of woody plants in the heath family, most with showy flowers...
species. In spring
Spring (season)
Spring is one of the four temperate seasons, the transition period between winter and summer. Spring and "springtime" refer to the season, and broadly to ideas of rebirth, renewal and regrowth. The specific definition of the exact timing of "spring" varies according to local climate, cultures and...
and summer
Summer
Summer is the warmest of the four temperate seasons, between spring and autumn. At the summer solstice, the days are longest and the nights are shortest, with day-length decreasing as the season progresses after the solstice...
, it migrates to spruce
Spruce
A spruce is a tree of the genus Picea , a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae, found in the northern temperate and boreal regions of the earth. Spruces are large trees, from tall when mature, and can be distinguished by their whorled branches and conical...
and infects recently emerged needles, coloring them in yellow
Yellow
Yellow is the color evoked by light that stimulates both the L and M cone cells of the retina about equally, with no significant stimulation of the S cone cells. Light with a wavelength of 570–590 nm is yellow, as is light with a suitable mixture of red and green...
. In autumn, the spores that developed on spruce infects the rhododendron again.