Characterization of Phytoplasmas Associated With Almond Diseases in Iran

Abstract

In recent years, almond witchesÕ-broom disease has been prevalent in almond growing areas in the centre and south of Iran. Furthermore, almond trees showing different symptoms of phytoplasma diseases such as little leaf, leaf rolling, dieback of branches, rosette and yellowing were observed in the central regions of Iran. DNA isolated from symptomatic almond trees was used to amplify 16S rDNA and 16S-23S rDNA intergenic spacer (IS) fragments by nested polymerase chain reaction (PCR) using phytoplasma universal primer pairs (P1 ⁄ P7, R16F2 ⁄ R2, PA2F ⁄ R and NPA2F ⁄ R). Phytoplasmas were detected in symptomatic almonds in two major almond-growing regions, Isfahan and ChaharMahal-O-Bakhtiari.Restriction fragment length polymorphism analyses of nested PCR products using endonuclease enzymes HpaII and TaqI revealed that phytoplasmas associated with infected almonds are genetically different. Sequence analyses of amplified fragments of 16S rDNA and IS region indicated that the almond phytoplasmas in Iran are closely related to ÔCandidatus (Ca.) Phytoplasma aurantifoliaÕ, ÔCa. Phytoplasma phoeniciumÕ, ÔCa. Phytoplasma solaniÕ and ÔCa. Phytoplasma trifoliiÕ. The phytoplasmas related to ÔCa. Phytoplasma aurantifoliaÕ were more prevalent than other phytoplasmas in the central regions of Iran.

‘Candidatus Phytoplasma asteris’ and ‘Candidatus Phytoplasma aurantifolia’, New Phytoplasma Species Infecting Apple Trees in Iran

“…; Zirak et al. ,b, ,b), it was expected that other fruit orchards in these regions might be affected with similar phytoplasmas. For many years, apple tress displaying several symptoms of phytoplasma diseases were observed in orchards located in Isfahan and ChaharMahal‐O‐Bakhtiari provinces.…”

Detection and Identification of a 16SrII Group Phytoplasma Causing Clover Little Leaf Disease in Iran

“…() are more suitable than others for detection of phytoplasmas in diseased perennial and annual plants in central Iran (Zirak et al. , ).…”

Molecular identification of diverse ‘Candidatus Phytoplasma’ species associated with grapevine decline in Iran

“…The presence of these phytoplasmas as well as of ‘ Ca . P. phoenicium’‐and ‘stolbur’‐related phytoplasmas is probably linked to the widespread presence of those phytoplasmas in the Iranian crops (Hosseini, Bahar, Madani, & Zirak, ; Salehi, Siampour, Esmailzadeh Hosseini, & Bertaccini, ; Salehi, Esmailzadeh Hosseini et al., ; Vali‐Sichani, Bahar, & Zirak, ; Zirak, Bahar, & Ahoonmanesh, ,b, ); however, the work about insect transmission to grapevine of all the phytoplasmas detected is still not yet achieved and will be carried out in future research.…”