Flickr photo FreeCat
late last year, warned the Galician hop Bursaphelenchus xylophilus, known as the pine wood nematode from Portugal, where in recent years has caused significant damage, in a similar way
to what occurred in the seventeenth century with Brown ink and the disappearance of that of the lowlands of West Peninsular.
Now, despite the drastic measures taken in Portugal, the nematode pest is spreading with great rapidity, which can cause the death of pine in less than three months.
Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle is a microscopic nematode was first detected in the United States, causing sudden dry pine early twentieth century. It was with the export of timber, when the nematodes began to be exported to other areas of the planet.
Since 1992, the Union European prohibited the sale of timber affected by the nematode, after which in 1984 detected the presence of the nematode in two timber imports from Asia softwood chips for the paper industry in Finland.
In late 1999, it was known that in Setubal (Portugal) had already affected by the nematode and in spite of the first measures to prevent spread of the pest (for years thought they had succeeded in stopping the expansion), the 2008, the European Union had to quarantine the pine trees of Portugal, preventing their sale to other EU countries.
In Spain, there were signs of the emergence nematode in Extremadura in 2008
, causing the existence of quarantine zones to prevent the expansion. In 2009, 70% of Extremadura pine had high or very high risk of suffering the infestation (PDF
), which was the ideal temperature zones for expansion (see below) and it is precisely in that year, when ordering the mandatory logging of the areas affected by the nematode, as it is the only way to stop the infestation.
Although called the pine nematode, and that is where he made his attack on living trees, are also considered host species of the genera
Abies, Cedrus, Larix, Picea, Peudotsuga Tsuga and
.
n Spain the species most affected seem to be P. sylvestris, P. nigra and P.pinaster. P.
and P. radiata halepensis have a somewhat lower sensitivity and P.
pinea has a higher level of resistance. In some areas of Portugal, it can also affect
Eucalyptus globulus.
The vector of the disease
Fotogarfía on Flickr
Ombrosoparacloucycle order to infect the pines, use an insect vector that will function as transport, as
Monochamus galloprovincialis Olivier
, a beetle family Cerambycidae jumping from pine to pine, but in his life, just move more than 3 kilometers (as is normal not to exceed 2 kilometers). 
Adults Monochamus sp., Arrive at the pine laden in their antennae to the nematodes from a previously infected tree. On the one hand, the nematode may enter through fungal hyphae are present in the trees or simply abandoning the adult insects to penetrate the tree sprouts from injuries. 
On the other hand, generates
Monochamus
galleries inside the pine, which causes commercial depreciation, reducing the possibility of selling even if treated with chemical treatments. On the other hand, generates Monochamus
B. xylophilus is an organism with a high biological plasticity, which makes it a very effective parasite can adapt to new situations with extreme ease. order to be established, the nematode needs a temperate climate above 20 degrees in summer, there is now established in the south of Pontevedra and above in areas of Extremadura, and that at temperatures above 20-25 degrees in July or August is observed tree mortality.
Moreover, the existence a deficit of moisture in the air and water stress to which are applied to the pine in the summer months is another factor favoring the development of the infestation. Its distribution is in those areas within 1,000 meters of altitude. When the nematode entered the Pine colonize resin canals and begins feeding of epithelial cells and the parenchyma of these channels. Thus, by affecting
resin canals, prevents the production of resin, the needles lose the ability to sweat.
pine begins to show the first symptoms like the withered tree and its needles turn yellow. Although showing needles on its branches in color pardoamarillo to 3 months, the tree is dead .
Video in English, explaining something about the whole process
performance measures
Once the pine is infested by the parasite is detected, the statement of the problem required authorities corresponding forest for immediate action. decreed an area A of a radius of between 1 and 2 km on the source of the problem, doing as far as possible, all possible efforts for the eradication, although in most cases the only way is by cutting down all the pins in a one kilometer radius to prevent the passage of the beetle. In Galicia, after the entry confirmation of the nematode, and is proceeding with the removal of all pine trees within a radius of 1.5 kilometers of focus of the problem in the municipality of As Neves (Pontevedra), affecting more than 1,000 homeowners in one of the most productive forest areas in Spain.
Before Spring, about 100,000 trees will have to be removed to prevent the spread of the disease as temperatures rise and the nematode have favorable temperature for action, as the winter cold, put it in a kind of lethargy.
Moreover, in another range of 20 kilometers, we proceed to the elimination of all those trees are dead or have a state of decay, as they may represent a suitable place for the vector can be fed . For timber harvested within the 20 km quarantine prohibiting the sale unless prior treatment with the introduction of wood in high temperature chambers to kill the parasite in the case is still in the wood already cut.
Desapación del Pino " Galicia?
fact that the situation enough to remember when
P hytophthora
cinnamomi Rands. caused the death and disappearance of European chestnut (Castanea sativa Mill) in the seventeenth century areas with an altitude of 400-500 meters below the Iberian Peninsula. This time the infection seems to be slowing down, but the same thought in Portugal and now the whole country is infected.
Chances are that in the nearby provinces of Portugal and Ourense and Pontevedra (also Extremeñas, although it seems that there is much more controlled), just wood highly productive areas of the Iberian Peninsula suffer the loss of much of Pinos, reaching an eventual demise in less than 5 years.
The problem is that it can be extended for the rest of the Iberian Peninsula, causing the disappearance of the pines in the most extreme case, in the next 15-20 years.
If you liked the news you can vote on it in Journals
More Information
-
Wikipedia: Bursaphelenchus xylophilus
- Bursaphelenchus xylophilus
- Danger's next for the pine forests of Spain and Portugal
- Principality of Asturias. Wood nematode pine: Bursaphelenchus xylophilus
- E l
)
- Bursaphelenchus xylophilus
- The threat to our forests -
-
The pinewood nematode: an opportunity for our forest? (I)
-
The pinewood nematode: an opportunity for our forest? (II)
-
"The worm of pine wood takes less than three months in dry tree"
-
Spain: The plague of pine nematode quarantine required to declare in the neighboring country
-
A microscopic worm to harvest about 100,000 forces in Galicia
pine - The sixteenth-century Portuguese trade and the disappearance of Castaño European - COMMISSION DECISION of 27 June 2008 concerning interim protection measures against the spread of
Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle et al. (The wood nematode pine) in Portugal - PDF
-
A deadly plague threatens Portugal from Galicia pines
-
A Galicia Forestry Association calls 'máis apoio' to you give owner polo nematode affected area
- Xunta de Galicia - PLAN OF
Bursaphelenchus CONTINXENCIA xilophilus - PDF
- The worm beats pine
-
The dreaded 'pine worm' appears in Extremadura
- B xylophilus
ursaphelenchus
, or worm pine, pine danger to English. -
pine 70% of Extremadura has high or very high risk of suffering from the 'worm pine'
- The "worm pine logging causes 200,000 trees north of Cáceres
- SOS: pine worm - and Solla A. Fernandez JM Risk maps emergence and disease development of pine wilt (Bursaphelenchus xylophilus
) in Extremadura. Invest Agrar: Sist Recur For (2006) 15 (2), 141-151 - PDF
0 comments:
Post a Comment