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Date: 28 Jan 2009
Source: The Statesman [edited]
<http://www.thestatesman.net/page.news.php?clid=23&theme=&usrsess=1&id=241841>

Late blight ruins potato cultivation in Bankura

Potato cultivation has gone down in most areas of Bankura this year [2009}. The agricultural authority has identified the disease 'late blight' as the cause behind the ruin of thousands of hectares of potato crops. According to principal agricultural officer of Bankura Mr Ajit Das: "We predict only 60 percent of the average yearly yield this season, and are yet to estimate the full extent of the damage."

The main affected areas fall under Taldangra, Joypur, Sonamukhi, Patrasayar, Kotulpur, Raipur, and Indas blocks. Many farmers have had to switch occupations, or supplement income. A senior official said:
"The temperature has risen to abnormal heights for the winter season.
Also, unusually foggy weather has worsened the situation due to the large amount of dew dropped on the cultivation."

Aside from late blight, the yield of potato crop has suffered from adverse effects caused by a medicine named [Dithane] M45 cultivated by a Punjab based agro firm to combat fungal infection in the potatoes. According to agriculture department officials, "The anti-fungal medicine has been lessening the basic yield of potatoes, adding to the farmers' problems. We have sent samples of the medicine to be tested at a state run laboratory in Midnapore."

According to Mr Bablu Santra, Patrasayar agriculture development
officer: "It is destroying the crop instead of removing the fungal infection. The farmers are facing an unprecedented crisis following the poor potato cultivation this year. The negative effects of the so-called 'medicine' have contributed to this crisis."

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[Potato late blight (PLB) is caused by the fungus-like organism _Phytophthora infestans_ and can cause 100 percent crop loss. It is spread by plant material, wind, and water. For more information on PLB see links and previous ProMED-mail posts below.

PLB disease management generally relies on fungicide treatments of seed tubers and crops. The name of the locally produced 'medicine'
above may refer to the fungicide Dithane M45, which can be used to combat PLB. Dithane M45 has been available for a long time and is considered very safe and non-toxic for plants, even at high concentrations (T. Wicks, South Australian Research and Development Institute, personal communication). Thus it is unlikely to cause damage to the potato plants, instead the problems described in this story may be due to contaminations or other errors.

PLB is also currently affecting potatoes in Punjab (ProMED-mail post no. 20090103.0018), and earlier outbreaks were reported from West Bengal and other Indian states in previous years.

Maps
India:
<http://www.globalsecurity.org/military/world/india/images/IndiaMap_tourism.gif>
and
<http://healthmap.org/promed/en?g=1277264&v=22.9,79.6,5>
West Bengal districts:
<http://www.mapsofindia.com/maps/westbengal/westbengal-district.htm>
Bankura district:
<http://www.mapsofindia.com/maps/westbengal/districts/bankura.htm>

Pictures of PLB symptoms:
<http://www.sciencedaily.com/images/2007/01/070102132649.jpg>  (tuber) and
<http://www-biol.paisley.ac.uk/bioref/Chromista/potato_blight.jpg>  (leaves)

Links
Late blight fact sheets:
<http://ohioline.osu.edu/hyg-fact/3000/3102.html>  and <http://vegetablemdonline.ppath.cornell.edu/factsheets/Potato_LateBlt.htm>
Disease history and background:
<http://www.apsnet.org/online/feature/lateblit/>  and <http://www.olympusmicro.com/micd/galleries/brightfield/potatoblight.html>
Late blight information and resources via:
<http://www.potato.org.uk/department/knowledge_transfer/fight_against_blight/advice_blight.html>
_P. infestans_ taxonomy:
<http://www.indexfungorum.org/Names/NamesRecord.asp?RecordID=232148>
Information on Dithane M45:
<http://www.dowagro.com/ca/prod/dithane-m45.htm> and <http://www.southernag.com/PDF%20Files/dithne.pdf>
Global Initiative on Late Blight:
<http://gilb.cip.cgiar.org/>.  - Mod.DHA]

[see also in the archive:
Late blight, potato - India: (PB) 20090103.0018
2008
----
Late blight, potato - India, Canada alert 20080815.2534 Potato diseases - India: (West Bengal) 20080206.0477
2007
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Late blight, potato - India (02): (Punjab, W Bengal) 20071221.4099 Late blight, potato - India: (Punjab), alert 20071116.3715 Late blight, potato - India, UK 20070509.1491
2006
----
Late blight, potato - India (Kashmir) 20060424.1200]