Turkish Journal of Agriculture and Forestry (2009) 33, 477-486
Khalid Pervaiz Akhtar, Ghulam Sarwar, Matthew Dickinson, Mushtaq Ahmad, Muhammad Ahsanul Haq, Sohail Hameed and Muhammad Javeed Iqbal (2009)
Sesame phyllody disease: its symptomatology, etiology, and transmission in Pakistan
Turkish Journal of Agriculture and Forestry 33 (5), 477-486
Abstract: Phyllody is a serious disease of sesame in Pakistan. In the present study investigations were carried out on the symptomatology, etiology, and transmission of this disease. Floral virescence, phyllody, and proliferation are the most common symptoms. Sometimes these symptoms are accompanied by yellowing, cracking of seed capsules, germination of seeds in capsules, and formation of dark exudates on the foliage. Shoot apex fasciation has also been occasionally observed, but no phytoplasma DNA has been detected in fasciated plants using PCR assays. Light microscopy of hand-cut sections treated with Dienes' stain showed blue areas in the phloem region of phyllody-infected plants. Pleomorphic bodies (phytoplasma structures) were observed in phloem sieve elements in diseased plants using transmission electron microscopy (TEM). Amplification of a phytoplasma characteristic 1250-bp 16S rDNA fragment confirmed that sesame was infected by a phytoplasma, and RFLP profiling and sequencing confirmed that the associated phytoplasma had the greatest homology to 16SrII-D group phytoplasmas. Phyllody disease was successfully transmitted by grafting dodder (Cuscuta compestris) and leafhopper (Orosius albicinctus). Treatment of infected plants with tetracycline-HCl provided temporary recovery from the disease.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Full text of article
Database assignments for author(s): Mushtaq Ahmad, M. Javed Iqbal
Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
Pest and/or beneficial records:
Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
---|---|---|---|---|
16SrII phytoplasma group | Sesame (Sesamum indicum) | Pakistan |