![]() ![]() The needles will then begin to show signs of infection, and eventually the pathogen produces stromata, which is the pathogen's fruiting body. The ideal germination temperature is 12-18 ☌, with high levels of humidity. Once the needles have been exposed and the fungus germinates, the pathogen then penetrates the needle through the stoma. Spread initially in moist conditions, the pathogen requires physical transport either through mist and rain, or by direct contact with other infected needles. This ongoing spread of infection weakens the tree over time, with larger percentages of crown infection leading to lower yields of timber and, in some cases, to the mortality of the tree. ![]() This infection is then passed on to the following years growth, which continues year after year. This can be seen clearly between the months of June and July, after which the needles begin to 'turn up', much like a lion's tail. This infection starts on the base of the crown on older needles, which then turn a brownish red at the tip, while the rest of the needle remains green. The first signs of infection that can be seen are yellow and brown spots that develop on the living needles, which soon turn red. The general opinion is that the disease has been prevalent in the Southern Hemisphere for some length of time, and that there are now high levels of infection in the Northern Hemisphere, with unprecedented records of the disease in Asia, Europe, and the UK. The origin is also thought to be from the high altitude rain forests of South America. The precise origins of the disease are unknown, although there are suggestions that the disease might be from the pine forests of Nepal, in the Himalayas. Between 19 the majority of reports were on Corsican pine in East Anglia, although it had been found in other parts of Britain. The disease spread sporadically until 1966, after which there were no new reports up until the end of the 1990s. It was first recorded in Britain on Corsican pine in 1954 in a nursery in Dorset. laricio) is the most susceptible species in Great Britain. Over 60 species have been reported to be prone to infection and Corsican Pine ( Pinus nigra ssp. This fungal disease affects the needles of conifers, but is mainly found on pine. ex Munk (1957) ĭothistroma septosporum or Mycosphaerella pini is a fungus that causes the disease commonly known as red band needle blight. ![]()
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