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Phytoplasma Infection (phytoplasma + infection)

Distribution by Scientific Domains

Life Sciences	100%

Selected Abstracts

Detection of Phytoplasma Infection in Rose, with Degeneration Symptoms

JOURNAL OF PHYTOPATHOLOGY, Issue 1 2001
M. Kami
In 1998 a severe disease was observed on rose cvs. ,Patina', ,Papillon' and ,Mercedes' cultivated in a commercial greenhouse in Poland. The symptoms included stunted growth, bud proliferation, leaf malformation and deficiency of flower buds. Sporadically some plants yielded flower buds transformed into big-bud structures and degenerated flowers. The presence of phytoplasma in roses with severe symptoms as well as in recovered plants and Catharanthus roseus experimentally infected by grafting and via dodder was demonstrated by nested polymerase chain reaction assay with primers pair R16F2/R2 or R16F1/R0 and R16(I)F1/R1 amplifying phytoplasma 16S rDNA fragment. The polymerase chain reaction products (1.1 kb) used for restriction fragment length polymorphism analysis after digestion with endonuclease enzymes AluI and MseI produced the same restriction profiles for all samples. The restriction profiles of phytoplasma DNA from these plants corresponded to those of an aster yellows phytoplasma reference strain. Electron microscope examination of the ultra-thin sections of the stem showed wall thickenings of many sieve tubes of the diseased roses and single phytoplasma cells within a sieve element of the phloem of experimentally infected periwinkles. This paper is the first report on aster yellows phytoplasma in rose identified at a molecular level. Detektion einer Phytoplasma-Infektion bei Rosen mit Degenerationserscheinungen Im Jahr 1998 wurde eine schwere Krankheit bei Rosen der Sorten ,Patina', ,Papillon' und ,Mercedes' festgestellt, die in einem polnischen Gewächshaus für kommerzielle Zwecke kultiviert wurden. Zu den Symptomen gehörten Kümmerwuchs, durchwachsene Knospen, Blattmißbildungen und ein Mangel an Blütenknospen. Einige wenige Pflanzen trugen übergroße Blütenknospen, die degenerierte Blüten hervorbrachten. Die Anwesenheit von Phytoplasmen in Rosen mit starken Symptomen, in erholten Pflanzen und in Catharanthus roseus, der durch Pfropfen und durch Teufelszwirn (Cuscuta) experimentell infiziert worden war, wurde mittels einer genesteten Polymerase-Kettenreaktion mit den Primerpaaren R16F2/R2 oder R16F1/R0 und R16(1)F1/R1 zur Amplifikation des Phytoplasma-16S rDNA-Fragments demonstriert. Die für die Analyse der Restriktionsfragmentlängenpolymorphismen nach Verdau mit den Endonucleasen AluI und MseI verwendeten PCR-Produkte (1,1 kb) produzierten bei allen Proben die gleichen Restriktionsprofile. Die Restriktionsprofile der Phytoplasma-DNA aus diesen Pflanzen entsprachen denjenigen eines Typenstamms eines Asternvergilbung auslösenden Phytoplasmas. Elektronenmikroskopische Untersuchungen ultradünner Schnitte des Stamms zeigten Wandverdickungen bei zahlreichen Siebröhren der erkrankten Rosen und einzelne Phytoplasmazellen innerhalb eines Siebelements des Phloems experimentell infizierter Immergrün-Pflanzen. Dies ist der erste Bericht über ein auf molekularer Ebene identifiziertes Asternvergilbungs-Phytoplasma bei Rosen. [source]

The Presence of Phytoplasma in Black Currant Infected with the Blackcurrant Reversion Disease

JOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2004

Abstract A plant of black currant cv. Karl,tejnský dlouhohrozen showing symptoms of the severe Russian (R) form of the blackcurrant reversion disease (BCRD) was shown to contain phytoplasma bodies measuring 530,750 nm. Phytoplasma infection was confirmed by polymerase chain reaction (PCR) with the universal primer pair R16F1/R16R0, followed by PCR with the primer pair fU5/rU3. A comparison of the sequence of an amplification product of approximately 880 bp with sequences available in the GenBank confirmed the classification of the phytoplasma in the 16SrI (Aster yellows group). This is the first evidence of the natural occurrence of phytoplasma infection in black currant. Blackcurrant reversion virus (BRV), the cause of BCRD, was confirmed in the plant by RT-PCR. A 481 nt cDNA fragment of BRV was sequenced and compared with sequences in GenBank. Rhabdovirus-like particles were also observed in the plant by electron microscopy. [source]

Phytoplasma from little leaf disease affected sweetpotato in Western Australia: detection and phylogeny

ANNALS OF APPLIED BIOLOGY, Issue 1 2006
F. Tairo
Abstract Symptoms of leaf and stem chlorosis and plant stunting were common in sweetpotato plants (Ipomoea batatas) in farmers' fields in two widely separated locations, Kununurra and Broome, in the tropical Kimberley region in the state of Western Australia in 2003 and 2004. In the glasshouse, progeny plants developed similar symptoms characteristic of phytoplasma infection, consisting of chlorosis and a stunted, bushy appearance as a result of proliferation of axillary shoots. The same symptoms were reproduced in the African sweetpotato cv. Tanzania grafted with scions from the plant Aus1 with symptoms and in which no viruses were detected. PCR amplification with phytoplasma-specific primers and sequencing of the 16S-23S rRNA gene region from two plants with symptoms, Aus1 (Broome) and Aus142A (Kununurra), revealed highly identical sequences. Phylogenetic analysis of the 16S rRNA gene sequences obtained from previously described sweetpotato phytoplasma and inclusion of other selected phytoplasma for comparison indicated that Aus1 and Aus142A belonged to the Candidatus Phytoplasma aurantifolia species (16SrII). The 16S genes of Aus1 and Aus142A were almost identical to those of sweet potato little leaf (SPLL-V4) phytoplasma from Australia (99.3%,99.4%) but different from those of the sweetpotato phytoplasma from Taiwan (95.5%,95.6%) and Uganda (SPLL-UG, 90.0%,90.1%). Phylogenetically, Aus1, Aus142A and a phytoplasma previously described from sweetpotato in the Northern Territory of Australia formed a group distinctly different from other isolates within Ca. Phytoplasma aurantifolia species. These findings indicate that novel isolates of the 16SrII-type phytoplasma pose a potential threat to sustainable sweetpotato production in northern Australia. [source]