Sponsored by the Molecular Plant Pathology Laboratory (MPPL)
|Ash yellows||Grapevine yellows||Coconut lethal yellowing||Chokecherry X-disease||Sweet potato little
|Malaysian periwinkle yellows|
|Periwinkle infected by
aster yellows phytoplasma strain NJAY
|Perkiwinkle infected by
inducing phytoplasma strain JR1
infected by peanut
witches' broom phytoplasma
of yellows disease
(Pictures are thumbnailed below, Please click to enlarge pictures of phytoplasma infected plants)
Healthy ash tree (left) and ash yellows (AshY) diseased ash tree (right, center, and bottom). Arrows indicate close-up views of witches' broom symptoms caused by ash yellows phytoplasma ('Candidatus Phytoplasma fraxini').
Left: grapevine yellows (GY) disease in Sicily, Italy; symptoms include yellowing of veins in leaves and necrosis of fruit. Right: grapevine yellows disease (VGY) in Virginia; symptoms include curling of leaves.
For more about Grapevine Yellows,
please click here
|Cabernet-Sauvignon grapevine plant showing symptoms of grapevine yellows disease in Virginia. Phytoplasma DNA was detected in the veins of leaves with symptoms. Photo by R.E. Davis, August 2010.|
|Chardonnay grapevine plant showing symptoms of grapevine yellows disease in Virginia. Phytoplasma DNA was detected in the veins of leaves with symptoms. Photo by R.E. Davis, August 2010.|
Healthy coconut (left) and coconut suffering from lethal yellowing (LY) disease (right) in Ft. Lauderdale, Florida, USA. Symptoms include yellowing and death of leaves. Coconut trees are killed by this disease.
|The spread of coconut lethal yellowing disease has been retarded by treatment of trees with a tetracycline antibiotic in Florida. The trunk of this tree shows locations where the antibiotic was injected.|
|Chokecherry infected by peach X-disease phytoplasma in Connecticut, USA. Symptoms include premature fall coloration of leaves.|
Healthy sweet potato (left) and sweet potato little leaf disease
(right) in Taiwan. Symptoms include reduced size of leaves
and stunting of the diseased plant.
|Dandelion phyllody disease in Udine, Italy. Arrows indicate symptoms of phyllody in flowers (left). Healthy plant is on the right.|
|Malaysian periwinkle yellows disease in Madagascar periwinkle (Catharanthus roseus) (right). Note severe yellowing of lower leaves, below which are normal green leaves. Plant also exhibits flower abnormalities of virescence and phyllody.|
|Red clover photographed in the field in Italy (right). Diseased flowers on left exhibit phyllody symptoms. Normal flower is on the right.|
|Symptoms induced in a diseased plant of Catharanthus roseus (Madagascar periwinkle) by peanut witches' broom phytoplasma. Peanut witches' broom phytoplasma is a member of phytoplasma 16S rDNA RFLP group 16SrII. Note symptoms of big bud, phyllody, and virescence of flowers.|
Latin names of plants -- Latin names of the plants should be in italic letters.
'Candidatus' names -- 'Candidatus phytoplasma asteris' should be written as 'Candidatus Phytoplasma asteris'. The correct abbreviation is 'Ca. Phytoplasma asteris'.
Designed and created by Jonathan Shao, email@example.com
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