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2022-07-14T04:06:00.0000000Z
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ALTERNARIA LEAF BLOTCH, APPLE - INDIA: (JAMMU AND KASHMIR)

ProMED
http://www.promedmail.org

Source: The Kashmir Walla [summ. Mod.DHA, edited]
https://thekashmirwalla.com/farmers-worried-as-fungal-disease-hits-apple-orchards-in-south-kashmir/

Apple growers in south Kashmir are concerned about the outbreak of alternaria leaf blotch in orchards, causing huge scars on the leaves of trees. The disease has spread over vast tracts of land after recent incessant rains. Trees are shedding leaves and fruit yield could be affected.

Authorities are asking growers to ensure proper orchard sanitation and use recommended fungicides as per their advisory. Due to weather conditions, most apple trees are experiencing physiological stress, giving rise to necrotic leaf blotch, lenticel blotch, yellowing of leaves, as well as the alternaria leaf blotch.
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Communicated by:
ProMED

[A number of members of the _Alternaria_ species complexes have been associated with diseases of apple, such as leaf blotch (_A. mali_), fruit spot, some fruit rots (_A. alternata_) and (together with a range of fungi from other genera) dry core rot. Development of these diseases is generally favoured by high humidity and prolonged leaf wetness. These risk factors may be increased by common orchard practices designed to improve yields, such as high density plantings and sprinkler irrigation. Spread may occur with contaminated plant material (including crop debris), by mechanical means (including insect and human activities), wind and rain. Disease management may include cultural practices to improve air circulation and reduce humidity in the orchards, as well as phytosanitation but relies mainly on fungicide programmes.

Other species in the genus _Alternaria_ cause, for example, early blight of potato and tomato (_A. solani_), leaf blight of tea (_A. alternata_), purple blotch of onions and related crops (_A. porri_), and almond leaf spot complex (_A. alternata_, _A. arborescens_, _A. tenuissima_).

Apple lenticel and necrotic leaf blotches, also mentioned above, are physiological disorders due to nutritional and/or environmental factors.

Maps
India (with states):
https://www.worldometers.info/img/maps/india_physical_map.gif
Jammu & Kashmir districts:
https://i.pinimg.com/originals/31/c4/d5/31c4d52542cb0c2f552cb3484ee4c6ba.jpg

Pictures
Alternaria symptoms on apple:
https://www.epicgardening.com/wp-content/uploads/2018/07/Alternaria-leaf-spot-in-apple-tree.jpg,
https://s3.amazonaws.com/plantvillage-production-new/images/pics/000/100/954/original/IMG_20170722_111527.jpg,
https://s3.amazonaws.com/plantvillage-production-new/images/pics/000/100/953/original/IMG_20170722_111601.jpg and
https://www.epicgardening.com/wp-content/uploads/2018/07/Alternaria-fruit-rot-in-apple.jpg
Photo gallery of some apple diseases & disorders:
http://www.ipmimages.org/browse/AreaSubs.cfm?area=74

Links
Additional news story:
https://www.greaterkashmir.com/todays-paper/editorial-page/pre-mature-falling-of-apples-from-trees
Alternaria diseases on apple:
https://www.cabi.org/isc/datasheet/4515 and
https://doi.org/10.1111/j.1365-3059.2012.02637.x
Alternaria information & diseases on various hosts:
https://www.epicgardening.com/alternaria-leaf-spot/
Information on _Alternaria_ species complexes:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4774270/,
https://doi.org/10.1016/j.funbio.2015.06.012 and via
https://www.wur.nl/de/Publicatie-details.htm?publicationId=publication-way-343930373638
Genus _Alternaria_ taxonomy and species list via:
http://www.indexfungorum.org/names/Names.asp
List of major diseases & disorders of apple
https://www.apsnet.org/edcenter/resources/commonnames/Pages/Apple.aspx
- Mod.DHA

India
Alternaria
Apple_leaf_blotch

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