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A field trial of 23 stylo taxa was assessed for susceptibility to stylosanthes little leaf (SLL) disease. The trial included Stylosanthes scabra cvv. Seca, Siran, and Fitzroy, S. guianensis var. guianensis cv. Cook, S. hamata cvv. Amiga and Verano and "Stylosanthes seabrana" cvv. Unica and Primar, as well as seven unreleased cultivars from a CSIRO anthracnose resistance breeding program, and four unreleased introduced lines. Plants that had SLL symptoms were sampled on six occasions from March to August 1999 and tested for phytoplasmas, the presumed causal organism of this disease, using the polymerase chain reaction (PCR). All taxa were found to be susceptible to SLL disease except S. hamata cv. Verano and "S. seabrana" cv. Unica. Varieties were ranked on disease incidence, with S. scabra varieties bred for anthracnose resistance having the highest incidence of the disease. These varieties also had significantly higher SLL incidence than that of the original introductions from which they were derived. Before testing, symptom profiles were recorded noting the presence of chlorosis, spike elongation, reddening of leaf tips and floral parts, and reduced leaf size (little leaf). Statistical analysis of the association of these characteristics with SLL disease showed that little leaf was the best disease indicator and that chlorosis and excessive reddening of leaf tips and floral parts were also associated with the disease. The presence of floral abnormalities was also recorded in the symptom profiles. At no time were normal flowers found on samples that had SLL, making this symptom a good indicator of SLL. However, not all plants with floral symptoms tested positive for phytoplasmas by PCR, probably because these symptoms are difficult to diagnose visually. Virescence and phyllody were the most common floral abnormalities and were found to be associated specifically with the phytoplasmas pigeon pea little leaf and sweet potato little leaf variant V4, respectively. An additional floral abnormality, termed abortion, was also observed in association with this disease.

Polymerase chain reaction (PCR) assays were used to detect phytoplasmas in foliage samples from Chinaberry (Melia azedarach) trees displaying symptoms of yellowing, little leaf and dieback in Bolivia. A ribosomal coding nuclear DNA (rDNA) product (1·8 kb) was amplified from one or more samples from seven of 17 affected trees by PCR employing phytoplasma-universal rRNA primer pair P1/P7. When P1/P7 products were reamplified using nested rRNA primer pair R16F2n/R16R2, phytoplasmas were detected in at least one sample from 13 of 17 trees with symptoms. Restriction fragment length polymorphism (RFLP) analysis of P1/P7 products indicated that trees CbY1 and CbY17 harboured Mexican periwinkle virescence (16SrXIII)-group and X-disease (16SrIII)-group phytoplasmas, respectively. Identification of two different phytoplasma types was supported by reamplification of P1/P7 products by nested PCR employing X-disease-group-specific rRNA primer pair R16mF2/WXint or stolbur-group-related primer pair fSTOL/rSTOL. These assays selectively amplified rDNA products of 1656 and 579 bp from nine and five trees with symptoms, respectively, of which two trees were coinfected with both phytoplasma types. Phylogenetic analysis of 16S rDNA sequences revealed Chinaberry yellows phytoplasma strain CbY17 to be most similar to the chayote witches’-broom (ChWBIII-Ch10) agent, a previously classified 16SrIII-J subgroup phytoplasma. Strain CbY1 resembled the Mexican periwinkle virescence phytoplasma, a 16SrXIII-group member. The latter strain varied from all known phytoplasmas composing group 16SrXIII. On this basis, strain CbY1 was assigned to a new subgroup, 16SrXIII-C.

Sesame phyllody disease associated with the presence of phytoplasmas is becoming a serious problem to many sesame growing countries of the world including India. However no systematic study on the disease has been done to assess the disease incidence, characterization of the associated phytoplasma strains and effect on the yield in north eastern states of India. Therefore an extensive survey was conducted from 2015 to 2017 in seven north eastern states of India covering 52 districts to record the incidence of the disease and to perform phytoplasma associated molecular characterization. The infected plants showed symptoms of virescence, phyllody, floral proliferation, flattened stem, splitting of capsules and witches’ broom. The disease incidence varied from 2% to 29% in different locations. The highest disease incidence (29%) was observed in the Sonitpur district of Assam in the variety ST-1683. Sesame phyllody infection was found to reduce the number of pod and seed yield per plant from 72.82%-100% and 57.20%-100%, respectively. A total of 96 symptomatic sesame samples were collected and analysed on extracted DNA with polymerase chain reaction using phytoplasma specific primers, amplifying 16S rRNA and secA genes. PCR and sequencing analysis confirmed the presence of ‘Candidatus Phytoplasma asteris’-related strains in all the symptomatic samples. Pairwise sequence comparison and phylogenetic analyses of 21 strains on 16S rRNA gene and 9 strains on secA gene sequences confirmed the phytoplasma classification in the aster yellows groups. Among the 7 leafhopper species collected only Hishimonus phycitis tested positive for sesame phyllody phytoplasma presence. Seven species of weeds and wavy leaf basket grass (Oplismenus undulatifolius) and flax (Linum usitatissimum) in and around the infected sesame fields were also positive for phytoplasma presence indicating them as potential reservoir hosts of the phytoplasma associated with sesame phyllody disease in the north east region of India.

Phytoplasma suspected symptoms of little leaf, chlorosis, yellowing, phyllody, witches’ broom, flat stem, flower virescence and stunting were observed in sixteen plant species during surveys in fields, gardens, fruit orchards and nurseries of six districts of Tripura, India in 2017–2018. Out of 15 symptomatic plant samples belonging to different species, 12 were positive through nested PCR assays for phytoplasma presence. Pair wise sequence comparison, phylogeny and virtual RFLP analysis of phytoplasma partial 16S rDNA sequences of these 12 samples indicated the presence of different phytoplasma groups and subgroups (16SrI-B, 16SrII-D, 16SrVI-D, 16SrXIV-A 16SrI, 16SrIX and 16SrXI). ‘Candidatus Phytoplasma asteris’-related phytoplasmas (16SrI-B) were identified in sesame phyllody affected plants at South Tripura and in crape jasmine, Celosia argentea and Zinnia elegans from Unakoti, Dhalai, North Tripura and West Tripura district. In West Tripura ‘Ca. P. australasiae'related phytoplasmas (16SrII-D) were identified with Jatropha hastata and bitter gourd; ‘Ca. P. trifolii’-related phytoplasmas (16SrVI-D) were identified in chili and brinjal and ‘Ca. P. cynodontis’-related phytoplasmas (16SrXIV-A) were identified in palm grass samples from Sipahijala district. ‘Ca. P. phoenicium’-related phytoplasmas (16SrIX) were identified in cowpea; ‘Ca. P. oryzae’-related phytoplasmas were identified in arecanut from North Tripura and ‘Ca. P. asteris’-related phytoplasmas were detected in Toona ciliata from Jampui Hills. This study suggests the presence of a wide genetic diversity of phytoplasmas infecting different crops and weeds in the Tripura state of India.

The atrium is an ancient concept. It has appeared in all kinds of buildings. Some methods about the atrium design are discussed in this paper from different aspects, in order to improve the ecological environment and reduce the energy consumption in the modern atrium buildings. The research used the comparative studying ways, combining various factors affecting the environment in modern architecture atriums. The best solution of the ecological atrium design is found by the analysis. It tells us the principles in the design of the ecological atrium from natural ventilation, the lighting, and virescence. All these aim at further understanding of the factors influencing the atrium, and providing a reference for the modern architecture design in the future. The conclusion of this paper can be applied directly to the design of public buildings, so as to effectively improve the ecological environment of our country. Thus, it is of great significance.

Phytoplasmas infestations are widely documented in angiosperms, especially in ornamental species (Chaturverdi et al. 2010). Infestations by these phloem-limited plant pathogenic bacteria may induce several symptoms such as loss of floral meristem determinacy and abnormal flower development, including virescence of floral organs and phyllody, i.e., replacement of floral organs by leaf-like structures (Lee et al. 2000, Chatuverdi et al. 2010). However, symptoms may also vary according to the plant host and other factors, such as localization of phytoplasmas in host tissues (Bertaccini 2007). Some species may be infested but remain asymptomatic by seasonal dormancy and they may act as reservoirs for the further spread of the phytoplasmas, involving insect vectors (Dermastia et al. 2017). Developments in the detection methods of phytoplasmas have contribute to a better understanding of these intriguing bacteria, and nowadays identification of these organisms rely mostly in molecular methods such as polymerase chain reaction of selected phytoplasma-specific gene regions (Dermastia et al. 2017). Our current understanding about phytoplasmas includes knowledge on how the phenotypes linked to the infestation by phytoplasmas are triggered: Kitazawa et al. (2017) presented results which suggest that these changes in floral organs are caused by the interactions of phyllogen (a virulence factor conserved in phytoplasmas) with ABCE-class MADS domains transcription factor (MTFs), which is known as key regulator of floral organs development in angiosperms.

Severe leaf scorch symptoms occurred on oriental lily hybrids cv. Woodriff's Memory cultivated in two commercial greenhouses in Poland. Symptoms included leaf necrosis and malformation, flower bud abscission and flower virescence, distortion and abortion. Naturally infected lily plants with severe symptoms in 1999 had retarded growth and leaf chlorosis and they failed to flower the following year. The presence of phytoplasmas in diseased lilies was demonstrated using nested polymerase chain reaction (PCR) assays with universal and 16SrI group specific primer pairs that amplified the phytoplasma 16S rDNA fragment. The PCR products (1.1 kb) of all samples used for restriction fragment length polymorphism analysis had the same restriction profiles after digestion with endonucleases AluI and MseI. The restriction profiles of phytoplasma DNA from these plants corresponded to those of an aster yellows phytoplasma reference strain.

The bottle gourd (Lagenaria siceraria [Mol] Standl.), member of Cucurbitaceae family, is a common and very popular vegetable grown in most parts of tropical and subtropical India and consumed in almost every household throughout the year. In India, 1.81 million tons of bottle gourd production was recorded from a cultivation area of 103.23 thousand hectares in 2015. Bottle gourd plants with typical virescence and phyllody symptoms, less vigor and stunted growth, were observed in fields in Pune district of Maharashtra state, during surveys in 2012, 2013, and 2014 (March to May). Affected plants showed the peduncle bearing floral parts abnormally elongated with no fruit setting. The observed symptoms were reminiscent of a phytoplasma infection. The average visual disease incidence was 0.51% in the surveyed areas, covering approximately 12,000 plants. To detect the presence of phytoplasma, 25 mg of leaf tissue from 26 representatives symptomatic and four asymptomatic plants were used for total DNA extraction using CTAB method. A phytoplasma 16S rRNA gene (1.25 kb) was detected in all selected symptomatic plant samples when tested using PCR assay with primers P1/P7 followed by nested PCR using R16F2n/R16R2 primers. Additionally, 480 bp of phytoplasma partial secA gene (Hodgetts et al. 2008) and 440 bp of the partial tuf gene (Makarova et al. 2012) was amplified, purified, and sequenced to confirm the phytoplasma presence. The 16S rRNA, secA, and tuf genes did not amplify by PCR in asymptomatic bottle gourd plant. The obtained 16S rRNA gene sequences (LT594117 and LT594118) from symptomatic plants showed 99.6% identity with a reference strain OAY (‘Ca. Phytoplasma asteris,’ M30790) when compared using the EzTaxon 16S rRNA database (Kim et al. 2012). The virtual RFLP pattern derived using iPhyClassifier from the R16F2n/R16R2 fragment of 16S rRNA sequences was found most similar to the reference pattern of strain BTSpLT138_IX, Papaya Bunchy top phytoplasma (16SrI-X, JF781308), with a pattern similarity coefficient of 0.98 (Zhao et al. 2009). The virtual RFLP patterns with AluI and MseI were confirmed by actual RFLP analysis. Furthermore, the partial sequences of secA (LT617882 and LT617883) genes showed 88% sequence identity with Chrysanthemum yellows (AJS09571) and New Jersey aster yellows (AJS09572), confirming the association of ‘Ca. P. asteris’ (16SrI) with symptomatic bottle gourd plants using NCBI-BLAST. The tuf gene sequences (LT617884 and LT617885) showed a sequence identity of 100% with Eggplant dwarf phytoplasma (BAC76339) reported from Japan. Previously, the 16SrIII-Y phytoplasma strain of ‘Ca. P. pruni’ was reported to be associated with L. siceraria yellows and little leaf in Brazil (Montano et al. 2015). This study is the first record of subgroup 16SrI-X of ‘Ca. P. asteris’ phytoplasma strain associated with virescence and phyllody disease symptoms in bottle gourd in India. This disease may become a serious threat to bottle gourd cultivation as it causes 100% yield loss due to floral abnormality and sterility. Also, bottle gourd is a regular and widely cultivated crop for a large community of farmers in India, making it more vital to study epidemiology of the new disease.

In São Paulo State, besides the occurrence of Candidatus Liberibacter americanus and Ca. L. asiaticus, a 16Sr IX group phytoplasma was associated with HLB symptoms, indistinguishable from those caused by liberibacters. This phytoplasma is called HLB phytoplasma and was found widespread in citrus orchards, although at low incidence. The same phytoplasma was found in Sunn Hemp (Crotalaria juncea) in 2008 and witches’-broom was commonly found associated with 16Sr group IX detection. The aim of this work was to assess the phytoplasma diversity in Sunn Hemp with emphasis at the detection of group 16Sr IX phytoplasma and to establish an association between the occurrence of HLB phytoplasma and symptoms. Sunn Hemp samples were harvested close to the blooming period. Plants were selected in the field when showing symptoms common to phytoplasma infection. We employed universal primers do amplify phytoplasmas in general and group specific primers for 16Sr group IX. PCR products were sequenced to allow grouping of phytoplasmas. We identified five phytoplasmas groups in 48 out of 99 Sunn Hemp plants, belonging to phytoplasma groups 16Sr I, III, VII, IX and XV. The most abundant phytoplasma was the group 16Sr IX, present in 70% of the samples, found in central and north São Paulo State. The occurrence of HLB phytoplasma in Sunn Hemp samples, showing 100% of similarity to the citrus phytoplasma, was highly related to virescence and the second most conspicuous symptom for this infection was witches’-broom.

Using molecular tools, the spread of phytoplasma diseases in a papaya plantation was investigated for 3 years to identify phytoplasma strains affecting papaya, insect vectors and alternative plant hosts. Five phytoplasma strains (SPLL-V4, TBB, CaWB, StLL and WaLLvar) were associated with papaya yellow crinkle disease and one phytoplasma strain (PDB) was associated with papaya dieback disease. The most prevalent strains were TBB and SPLL-V4 which occurred in 94% of infected papaya. There was a significant correlation between phyllody and TBB, and virescence and SPLL-V4, although other phytoplasma types could also be associated with either phyllody or virescence. No mixed infections were detected in diseased papaya. Disease progress curves for TBB and SPLL-V4 showed a sigmoid response reaching a maximum disease incidence of 16% after 24 months. The rate of disease spread was best described by a logistic model which showed that TBB spread at a slightly higher rate than SPLL-V4. Ten phytoplasma strains were detected in 14 alternative plant species; however, TBB and SPLL-V4 were present in only a few individual plants of some of these species, so these alternative hosts would probably not have provided a significant infection source to papaya. Very few phytoplasmas were detected in leafhoppers collected over 3 years with TBB and SPLL-V4 only detected in Orosius spp.

Grindelia robusta, a perennial herb, contains an essential oil that is used as an antitussive, sedative, and analgesic agent. During the spring of 2007, 'Candidatus Phytoplasma asteris'-related phytoplasmas were identified in plants showing virescence and phyllody symptoms. The qualitative and quantitative composition of the oil of healthy and infected plants was compared by gas chromatography/mass spectrometry. Samples from six symptomatic and five asymptomatic plants tested by nested PCR followed by RFLP analyses confirmed the presence of 'Ca. P. asteris' in all symptomatic samples. The oils from healthy and infected plants, obtained by steam distillation, contained 42 components ; that of healthy plants contained a higher concentration of monoterpenes, especially limonene and bornyl acetate, which were nearly 50% higher.

Naturally diseased plants of clover (Trifolium spp.) exhibiting symptoms of clover phyllody (virescence and phyllody of flowers) or of clover dwarf (abnormally small leaves, shortened internodes, proliferation of shoots, and dwarf growth habit) were observed in fields in Lithuania. Phytoplasma group-specific polymerase chain reactions (PCRs) and restriction fragment length polymorphism (RFLP) analysis of 16S rDNA revealed that the plants were infected by two mutually distinct phytoplasmas. Clover phyllody-diseased plants were infected by a subgroup 16SrI-C (subgroup I-C) phytoplasma (CPh-L) related to clover phyllody (CPh-C) phytoplasma in Canada. Clover dwarf-diseased plants were infected by both CPh-L and a phytoplasma (CYE-L) related to clover yellow edge (CYE-C) phytoplasma (subgroup 16SrIII-B = III-B) in Canada. A 1.8-kbp fragment of rRNA operon from CYE-L was amplified, cloned, and sequenced, and putative restriction sites mapped. This sequence shared high similarity (99.7%) with that of CYE-C and exhibited no differences from CYE-C in RFLP patterns of 16S rDNA; therefore, we tentatively classified CYE-L in subgroup 16SrIII-B (type strain, CYE = CYE-C phytoplasma) of the X-disease phytoplasma group. These findings extend the known geographical ranges of subgroup I-C and subgroup III-B taxa to the region of northern Europe including Lithuania and suggest a role of the subgroup III-B phytoplasma in clover dwarf disease.

In 1996–1998 on Gladiolus plants cultivated in Poland severe symptoms were observed. The symptoms included chlorosis of the youngest leaves, yellowing and malformation of flower spices, flower discoloration and virescence. The affected corms kept in cold storage developed premature multiple sprouts weak and pale in color. Their root formation was strongly inhibited.

Restriction fragment length polymorphism and sequence analysis of PCR-amplified ribosomal DNA were used to identify and classify phytoplasmas associated with diseases of various wild and cultivated plants. The diseases examined were either not known before or the presumable causal agents were not yet identified and characterized or were only known from other geographic areas. New diseases examined were those causing virescence and phyllody of Bunias orientalis and Cardaria draba. Both were associated with strains of the aster yellows phytoplasma. The same type of aster yellows phytoplasma was also found to be associated with yellows and phyllody diseases of Portulaca oleracea, Stellaria media, Daucus carota ssp. sativus, and Cyclamen persicum. In German and French DNA samples from diseased Trifolium repens, the clover phyllody phytoplasma was identified, which could clearly be distinguished from other phytoplasmas of the aster yellows group. Strains of the stolbur phytoplasma were detected in big bud-affected tomatoes and almost exclusively in Convolvulus arvensis. In Cirsium arvense and Picris echioides two distinct phytoplasmas were identified which showed relationship to the sugarcane white leaf phytoplasma group but may represent a new group or subgroup. In Conyza (syn.: Erigeron) canadensis a phytoplasma of the X-disease group was detected. A strain from Gossypium hirsutum showed the same restriction profiles as the faba bean phyllody phytoplasma.

Several plants of Catharanthus roseus cv ‘leafless inflorescence (lli)’ showing phenotype of phytoplasma infection were observed for symptoms of early flowering, virescence, phyllody, and apical clustering of branches. Symptomatic plants were studied for the presence/absence and identity of phytoplasma in flowers. Transcription levels of several genes involved in plants’ metabolism and development, accumulation of pharmaceutically important terpenoid indole alkaloids in flowers and leaves and variation in the root-associated microbial flora were examined. The expression profile of 12 genes studied was semi-quantitatively similar in control leaves and phytoplasma-infected leaves and flowers, in agreement with the symptoms of virescence and phyllody in phytoplasma-infected plants. The flowers of phytoplasma-infected plants possessed the TIA profile of leaves and accumulated catharanthine, vindoline, and vincristine and vinblastine in higher concentrations than leaves. The roots of the infected plants displayed lower microbial diversity than those of normal plants. In conclusion, phytoplasma affected the biology of C. roseus lli plants multifariously, it reduced the differences between the metabolite accumulates of the leaves and flowers and restrict the microbial diversity of rhizosphere.

Background Phytoplasmas are always associated with symptoms in host plants such as stunting of stems, witches’-broom, yellowing of leaves, formation of sterile-deformed flowers, virescence and phyllody. Recently also symptom of fasciation was reported associated with phytoplasma presence. In the present work, China ixeris fasciation was observed associated with phytoplasmas in Guanzhong Area, Shaanxi, China. Results Phytoplasma-like bodies were observed under transmission electron microscope in stem tissues of symptomatic samples. The 16S rRNA operon and tuf genes from phytoplasmas were amplified by PCR assays. Phylogenetic trees were calculated respectively based on sequences data of these two genes. The pattern of restriction fragment length polymorphism (RFLP) was generated via digesting the PCR products of 16S rRNA gene with eight restriction enzymes. Conclusion The presence of phytoplasma in China ixeris exhibiting fasciation symptom was confirmed by the results of TEM observation and PCR testing. Based on sequence data, phylogeny analysis and actual restriction fragment length polymorphism (RFLP) analysis, the associated phytoplasma was classified as related to 16SrI-C subgroup. This was the first record of phytoplasmas in China ixeris.

Disease symptoms characterized by phyllody, yellowing of leaves, stunting, and virescence were observed in economically important fodder crops like alfalfa and “bajra” x napier grass hybrid grass. Similar symptoms were found in bell pepper or “shimlamirch”, a common vegetable grown all over India; “bajra” a significant widespread cereal crop in Maharashtra and Karnataka and in the nuisance weed Parthenium hysterophorus collected in the vicinity of above fodder growing fields. The successful amplification of specific 16S rRNA gene in all collected symptomatic plants confirmed the presence of phytoplasmas and their sequences analysis revealed their close relationship with strains of ‘ Candidatus Phytoplasma australasia’. Using EzTaxon, a microbial 16S rRNA sequence database, and i PhyClassifier- an online phytoplasma taxonomy tool, group 16SrII, subgroup D was identified for the classification of these sequences. This is the first report of 16SrII-D phytoplasmas associated with phyllody and yellowing diseases of “bajra” and bell pepper in India (PDF) First report of 16SrII-D phytoplasmas associated with fodder crops in India. Available from: https://www.researchgate.net/publication/322687543_First_report_of_16SrII-D_phytoplasmas_associated_with_fodder_crops_in_India [accessed Dec 24 2018].

During 2012-2014 surveys for phytoplasma diseases, a phyllody symptomatology was observed in Eruca sativa in Abarkooh (Yazd province, Iran). The highest disease incidence was 32% in Ali Abad-e Shams (Esfandabad), and infected plants showed crown proliferation, witches’ broom, little leaf, flower virescence, phyllody, sterility, and plant stunting. Total DNA extracted from symptomatic and asymptomatic plants was tested for phytoplasma presence verification by direct PCR using P1/P7 primers and nested PCR using P1/P7 and R16F2n/R16R2 primers pairs. PCR amplicons of about 1.8 and 1.25 kb respectively, were obtained from all symptomatic E. sativa plants, but not from the symptomless ones. Restriction fragment length polymorphism analysis of R16F2n/R2 amplicons using AluI, HhaI, HinfI, HpaII, MseI, RsaI and TaqI restriction enzymes showed profile identical to each other and also to those of 16SrI phytoplasmas indicating that the phytoplasmas, associated with E. sativa phyllody are members of 16SrI group. The consensus sequence of Ali Abad-e Shams E. sativa phyllody strain showed 100% identity with those of the ‘Candidatus Phytoplasma asteris’-related strains. Phylogenetic analysis confirmed that this phytoplasma clustered within the 16SrI phytoplasma clade closer to the onion yellows mild strain (OY-M) a 16SrI-B phytoplasma. Restriction analysis using iPhy Classifier confirmed that virtual RFLP patterns of the phytoplasma were identical (similarity coefficient 1.00) to OY-M strain. A 16SrI-B related phytoplasma has been reported associated with rapeseed (Brassica napus) phyllody in Iran and Eruca sativa may be a secondary host for the 16SrI-B phytoplasma associated with rapeseed phyllody.

The presence of phytoplasmas in potted cyclamen plants showing malformations, phyllody and virescence of the flowers was detected by PCR assays with primers amplifying phytoplasma 16Sr, GroEL, secY, rp, tuf and amp genes. RFLP analyses allowed to identify the detected phytoplasmas in the aster yellows subgroup 16SrI-B. These phytoplasmas were identical to each other and to reference strains belonging to 16SrI-B subgroups on all studied genes except amp gene, and were further classified as rpI-B, SecYI-B and GroELI-III groups. This multigene characterization of a ‘Candidatus Phytoplasma asteris’-related strain infecting cyclamen in Italy allows its distinction from reference strains by RFLP analyses of the amp gene.

Transmission of phytoplasmas from naturally infected plant host species using the parasitic plant Cuscuta spp. (dodder) to Catharanthus roseus (Madagascar periwinkle) is an effective way to maintain a wide range of phytoplasmas for further research. Here, we describe transmission via dodder from an infected medicinal plant Rehmannia glutinosa var. purpurea and from a symptomatic redcurrant plant (Ribes spp.) to C. roseus indicator plants using a "stable bridges" method. In both cases, typical symptoms of phytoplasma disease on periwinkle plants were obtained: virescent flowers with an increased number of axillary shoots and smaller leaves after transmission from R. glutinosa, and greening petals (virescence) after transmission from Ribes spp. Phytoplasmas could be detected in donor and recipient plants by electron microscopy and by polymerase chain reaction (PCR) assays using universal phytoplasma primer pairs. Restriction fragment length polymorphism analyses of PCR fragments can also be used to confirm the identity of the phytoplasmas from donor and recipient plants.

Periwinkle (Catharanthus roseus), a tropical perennial plant, was found to be infected by a phytoplasma. Plants exhibiting virescence, phyllody and variegation symptoms were collected in the states of Minas Gerais and Sao Paulo, Brazil. The phytoplasma was transmitted by grafting from an infected periwinkle plant to healthy plants and by dodder to a citrus plant. Phytoplasma isolates from periwinkle plants from Brazil had the 16S rDNA gene sequenced and were classified in the 16SrIX group, subgroup A, belonging to the 'Candidatus P. phoenicium' species.

Chromosomal DNA fragments from the mycoplasma-like organisms (MLOs) associated with American aster yellows, apple proliferation, clover phyllody, and vaccinium witches' broom were cloned. Several MLO-specific fragments from each of these four isolates and a sequence from the 16S rRNA gene of an aster yellows MLO were used in Southern blot hybridizations to investigate the taxonomic relationships of 26 pathologically and geographically diverse MLOs. These MLOs were divided into four categories according to the symptoms induced in periwinkle. Genotypically, these isolates represented four groups (16S RFLP groups) of a classification based on restriction fragment length polymorphisms (RFLP) and sequencing data of the 16S rRNA gene. Probes from three isolates of one symptom category hybridized with isolates from all symptom categories. This result indicates that classification of MLOs by symptomatology does often not coincide with genetic relationships. The hybridization results confirmed the findings, of the 16S RFLP classification that most MLOs from herbaceous plants, especially those inducing virescence in periwinkle, are interrelated. These isolates, which were assigned to one 16S RFLP group, could be further differentiated in this study. Itcould be shown that aster yellows, clover phyllody, stolbur, and safflower phyllody and sandal spike are caused by distinct MLOs. The MLOs associated with apple proliferation, vaccinium witches' broom, and witches' broom of lime as well as two isolatesfrom, stone fruits could also be recognized as distinct organisms.

Samples from toria plants (Brassica rapa L. subsp. dichotoma (Roxb.)) exhibiting phyllody, virescence, witches broom, extensive malformation of floral parts, formation of bladder like siliquae and flower sterility were collected from four different locations in India. Sequencing and phylogenetic analysis of the 16S rRNA, a part of 23S rRNA, partial sec A genes, rp gene and 16S–23S intergenic spacer region indicated that the phytoplasmas associated with toria phyllody (TP) symptoms were identical and belonged to 16SrIX phytoplasma Pigeon pea witches’-broom (PPWB) group. The iPhyClassifier generated virtual RFLP pattern of 1.25 kb 16S rDNA sequences indicated that TP phytoplasma belongs to 16SrIX-C phytoplasma subgroup. Complete 23S rRNA gene of TP phytoplasma had 2,787 nucleotides and is the first sequence of 16SrIX phytoplasma group. Restriction digestion of 16S rDNA and 23S rDNA PCR products has also shown that TP phytoplasmas from all the four locations in India were identical. Toria is a previously unreported host for a phytoplasma in16SrIX-C subgroup.

Phyllody is a destructive disease of sesame (Sesamum indicum L.) in Iran. The major symptoms of the disease are floral virescence, phyllody and proliferation. Other symptoms which sometimes accompany the disease are yellowing, cracking of seed capsules, germination of seeds in the capsules and formation of dark exudates on the foliage. Light microscopy of hand-cut sections of sesame and colza (Brassica napus L. cv. Oro) stems treated with Dienes' stain showed blue areas in the phloem region of phyllody infected plants. Mycoplasma-like bodies were found in the sieve cells of infected sesame stems when thin sections were examined m an electron microscope. Sesame phyllody was successfully transmitted from sesame to sesame by grafting. Among various leafhoppers collected in sesame fields only Neoaliturus haematoceps transmitted the disease. This is the first report on the identification of a Mycoplasma-like organism (MLO) as the cause of sesame phyllody and N. haematoceps as an MLO vector in Iran. In host range studies using the leafhopper vector, only B. napus cv. Oro, Lepidium sativum, Catharanthus roseus, Lactuca sp. and Portulaca oleracea, but not 17 other species, developed symptoms. The species of vector and host range of MLO indicate that sesame phyllody in Iran is different from that reported in India and Upper Volta.

SUMMARY Taxonomy: Superkingdom Prokaryota; Kingdom Monera; Domain Bacteria; Phylum Firmicutes (low-G+C, Gram-positive eubacteria); Class Mollicutes; Candidatus (Ca.) genus Phytoplasma. Host range: Ca. Phytoplasma comprises approximately 30 distinct clades based on 16S rRNA gene sequence analyses of ~200 phytoplasmas. Phytoplasmas are mostly dependent on insect transmission for their spread and survival. The phytoplasma life cycle involves replication in insects and plants. They infect the insect but are phloem-limited in plants. Members of Ca. Phytoplasma asteris (16SrI group phytoplasmas) are found in 80 monocot and dicot plant species in most parts of the world. Experimentally, they can be transmitted by approximately 30, frequently polyphagous insect species, to 200 diverse plant species. Disease symptoms: In plants, phytoplasmas induce symptoms that suggest interference with plant development. Typical symptoms include: witches’ broom (clustering of branches) of developing tissues; phyllody (retrograde metamorphosis of the floral organs to the condition of leaves); virescence (green coloration of non-green flower parts); bolting (growth of elongated stalks); formation of bunchy fibrous secondary roots; reddening of leaves and stems; generalized yellowing, decline and stunting of plants; and phloem necrosis. Phytoplasmas can be pathogenic to some insect hosts, but generally do not negatively affect the fitness of their major insect vector(s). In fact, phytoplasmas can increase fecundity and survival of insect vectors, and may influence flight behaviour and plant host preference of their insect hosts. Disease control: The most common practices are the spraying of various insecticides to control insect vectors, and removal of symptomatic plants. Phytoplasma-resistant cultivars are not available for the vast majority of affected crops.

During a survey on mustard fields in 2016, symptoms including flat stem, phyllody and virescence were observed at Jhangha (Gorakhpur district) and Kumarganj (Faizabad district), Uttar Pradesh, India. The total DNA extracted from symptomatic mustard samples from both locations (GKP and FZ samples) yielded 1.3 kb amplicons with the universal phytoplasma primers P1/P7 followed by 3Far/3Rev in nested PCR assays. Samples from asymptomatic mustard plants from both locations resulted negative in the same assays. BLAST analysis of 16S rRNA partial gene sequence of one mustard GKP strain showed sequence similarity with phytoplasmas classified in rice yellow dwarf group (16SrXI), while the mustard phytoplasma FZ strain showed similarity with strains belonging to the clover proliferation (16SrVI) group. Phylogenetic analysis and virtual gel plotting on 16S rDNA sequences of both mustard phytoplasma strains indicated their closer relationships with 16SrXI-B and 16SrVI-D phytoplasma subgroups, respectively. This is the first detection and preliminary identification of these phytoplasmas in mustard.

Qassim region is one of the main agricultural areas in Saudi Arabia. During 2015, ornamental, landscape and bindweed plants showing virescence; yellowing, phyllody, witches’ broom, proliferation, fasciation, short internode, and dieback symptoms were observed in this region. To confirm the presence of phytoplasmas, DNA extracted from symptomatic and asymptomatic plants was used to amplify 16S rRNA-encoding gene through direct and nested PCR assays using P1/P7, R16F2n/R16R2 and fU5/rU3 primers. Phytoplasma DNA was detected in all symptomatic plants collected. Sequencing and phylogenetic analysis were performed to identify the phytoplasmas detected. BLAST comparison indicated that the phytoplasmas showed more than 99.2% identity with phytoplasmas in 16SrII group. Three phytoplasma strains from Albizia and periwinkle shared 100% identity with ‘Candidatus Phytoplasma aurantifolia’, subgroup 16SrII-B, while phytoplasmas affecting Parkinsonia aculeate, Gazania rigens, Hibiscus rosa-sinensis, Calendula officinalis, Plectranthus scutellarioides, Convolvulus arvensis, Zinnia Magellan, Conocarpus lanceolatus and Catharanthus roseus were identical to papaya yellow crinkle, classified in the 16SrII-D subgroup.

Bell pepper, also known as sweet pepper ( Capsicum annuum ), is an important economic vegetable in Iran. In February 2015, typical symptoms of phytoplasma disease, including yellowing, big bud, little leaf and virescence were observed in…

Inheritance of 81A genetic male-sterility with ‘virescent’ marker character and its cytology in Upland cotton (Gossypium hirsutum L.) are presented. The chromosome number of 81A is normal, 2n = 52, and pollen abortion occurs mainly in the late uninuclear stage. Male-sterility and virescence in 81A are controlled by one pair of recessive gene. Because male sterility and virescence showed no recombination, pleiotropy is assumed. However, very close linkage could not be ruled out. Allelic tests indicated that virescence observed in 81A is non-allelic to all virescence genes identified earlier in Upland cotton and its male-sterility is non-allelic to msc1, msc2 and msc3 discovered in P.R. China. It is proposed that 81A male-sterile gene symbol be tentatively named to msc7. The development of 81A genetic male-sterile line associated with virescence trait could raise considerably the efficiency of the hybrid seed production in cotton.

Infrared color remote sensing is always possessed of the consequence. The level of the virescence is a quite important synthetic index for appraising a city, so infrared color remote sensing is brought into play to it's the important function in the application of detecting urban virescence. But in the city, ground- object complexity, high-building gather, a mass of shadows being, and numbers of color ground-object being. All of them are main disturbing source to extracting vegetation information. That is a topic of the day how resists their disturbance. This paper just about aim at the problems, to discuss Retinex helpfully to attaint goal that resisting disturbance of the hereinbefore disturbing sources in extracting vegetation information from infrared color remote sensing images.

In April 2007, a severe disease occurred in Sicily (Italy) in a glasshouse cultivation of tenweeks stock belonging to the cultivar White-Beach. Plants were stunted and rosetted, and the flowers were of small size and characterized by virescence symptoms. Phytoplasma presence and identity was detected by applying PCR/RFLP techniques and sequencing of 16S ribosomal gene. Phytoplasmas were identified as belonging to ribosomal subgroup 16SrII-A, never reported before in Italy and showed 99% of homology with ‘Candidatus Phytoplasma aurantifolia’ and related phytoplasmas. This is the first report of a phytoplasma disease of tenweeks stock. Considering that this Brassicaceae ornamental species is widely grown in Italy, it could play an important role in spreading these phytoplasmas, new for Italy.

International audience; A survey for phytoplasma diseases in tomato and pepper fields in Lebanon was conducted during 2003 and 2004. Tomato plants with stunting, yellowing or purplish leaves, proliferation of laterals buds, hypertrophic calyxes and virescent flowers were found in 25% of the tomato fields surveyed, where they represented 2–8% of the plants. Pepper plants displaying stunting and yellowing of leaves, were found in 27% of the fields and 1–4% of the plants were affected. Phytoplasmas infecting tomato and pepper had identical 16S-rDNA RFLP profiles and sequences. A phytoplasma isolate named PTL was transmitted by dodder from a diseased tomato plant to a periwinkle (Catharanthus roseus) plant in which it induced leaf yellowing, virescence and phyllody. 16S-rDNA phylogenetic analysis classified PTL as a strain of ‘Candidatus Phytoplasma trifolii’.

In April 2007, a severe disease occurred in Sicily (Italy) in a glasshouse cultivation of tenweeks stock (Matthiola incana R. Br.; Brassicaceae) belonging to the cultivar White-Beach. Plants were stunted and rosetted, and the flowers were of small size and characterized by virescence symptoms. Phytoplasma presence and identity was detected by applying PCR/RFLP techniques and sequencing on 16S ribosomal gene. Phytoplasmas were identified as belonging to ribosomal subgroup 16SrII-A, never reported before in Italy and showed % of homology with ‘Candidatus Phytoplasma aurantifolia’. This is the first report of a phytoplasma diseases of tenweeks stock. Considering that this Brassicaceae ornamental species is widely grown in Italy, it could play an im-portant role in the epidemiology of these phytoplasmas, new for Italy, spreading.

Chrysanthemum (Chrysanthemum indicum L.) is an important floriculture crop grown in different parts of Karnataka, India for its beautiful cut flowers. Recently, there has been a decline in flower quality due to major pests and diseases. A field survey conducted during 2012-2013 in chrysanthemum-growing areas revealed the occurrence of virescence with an incidence of 5 to 10% in nearly 6 to 8 ha of chrysanthemum fields in Mandya and Mysore districts. Symptoms including malformed flowers with greenish florets and reduced flower size and floral virescence with sepaloidy were observed. Diseased leaves and flower parts were collected and used for identification of the causative agent. Ten samples (6 symptomatic, 2 healthy, and 2 phytoplasma-associated with phyllody of Catheranthus roseus as positive control) were used for total genomic DNA isolation using GenElute Plant Genomic DNA Miniprep Kit (Sigma-Aldrich, St. Louis, MO) and the DNA was used as template to amplify the phytoplasma-specific 16SrDNA gene using P1/P7 primers followed by nested PCR using R16F2n/R16R2 primers (Gundersen and Lee 1996). The expected 1.25-kb amplicon was detected only with DNA from symptomatic and positive control samples. Nested PCR products of all six phytoplasma-associated samples were purified and sequenced from both the directions using a ABIx370 Genetic Analyzer (Applied Biosystems, Waltham, MA). The 16SrDNA sequences were aligned using CodonCode Aligner (Centerville, MA) and analyzed by BLASTn. The analysis revealed that all six sequences shared 100% identity with Cassava witches broom (KM280680.1) and Peanut witches broom (JX403944.1) phytoplasma. The in-silico RFLP pattern of F2n/R2 primed region of 16SrDNA gene analyzed by using iPhyClassifier (Zhao et al. 2009) revealed that the sequence shared 99.8% nucleotide sequence similarity with coefficient value of 1.00 to the reference strain RFLP pattern of 16Sr group II, subgroup A (Peanut witches broom phytoplasma; Accession No. L33765.1). Based on 16SrDNA sequences and in-silico RFLP analysis, the phytoplasma associated with the chrysanthemum virescence was identified as a member of 16SrII-A group. The representative sequence was deposited in GenBank with Accession Number KP027534.1. Phytoplasma associated with little leaf and witches broom of chrysanthemum have been reported earlier from India and were assigned to groups 16SrI-A and 16SrII, respectively (Kumar et al. 2012; Raj et al. 2007). Chrysanthemum virescence phytoplasma belonging to Candidatus phytoplasma aurantifolia has been reported from Japan and has not been assigned to any group (Naito et al. 2007). The occurrence of virescence is of great importance as it affects the overall productivity and quality of flowers, which reduces the market value of chrysanthemum. To our knowledge, this is the first report of a group 16SrII-A phytoplasma associated with chrysanthemum virescence in India.

Tragopogon dubius (yellow salsify, Asteraceae) is a perennial herb in Iran. In a survey conducted for phytoplasma diseases in 2014, T. dubius witches' broom disease was observed in vineyards and green areas of Bajgah and Zarghan localities…

During a 2012-14 survey for phytoplasma diseases, Eruca sativa phyllody (ESP) disease was observed in Abarkooh (Yazd province, Iran). Infected plants showed crown proliferation, witches' broom, little leaf, flower virescence, phyllody,…

Rubus stunt phytoplasma (RS), a member of the elm yellows phytoplasma group, is widespread in Rubus in continental Europe. The recent introduction of new berry cultivars in Trento province (Northern Italy) prompted us to obtain more information about the spreading of RS and other phytoplasmas in these crops. In late spring/summer 2002 field observations were carried out in different commercial berry fruit crops and in related wild species. Rubus stunt-like symptoms were observed only in few plants of Rubus spinosa cv. Topee and in almost the 43 % of plants in a blackberry crop of 'Lochness' located in the Adige valley. The predominant symptoms observed on these two-three years old plants have been virescence, phyllody and other severe flower and fruit anomalies. Stunted growth, short internodes, few canes, proliferation of shoots from the base and leaf reddening in early autumn were also common. RS has been reported to be spread mainly by leafhoppers (Macropsis sp.). Chromotropic traps used in the crops did not permit captures of individuals of Macropsis spp; Macrosteles cristatus, the largest leafhopper collected, was analysed. The results confirmed a strict association between the symptoms and the detection of RS phytoplasma; no other phytoplasmas were found. PCR and nested-PCR also failed to detect phytoplasmas in the symptomless plants and in all Macrosteles groups tested. Rubus stunt is not widespread in the Trento province and Macropsis fuscula hasn’t been found; therefore vegetative propagation might have contributed to the dissemination of this pathogen. For this reason epidemiological studies are in progress, also on wild blackberries, to detect and eliminate sources of infection.

The Virescence Separator of Beijing, the capital city of China, is a virescence zone between the central area and the edge group as well as the zone among different edge groups, within irregular shape and the total area of 240 square kilometers. The construction of the Virescence Separator is a big and difficult project, an effective information system for planning and development with satisfactory performance is therefore essential. In this paper, the applications of remote sensing and GIS (Geographical Information System) technologies in BJVSIS (planning and development Information System for Beijing Virescence Separator), including three dimensional (3D) visualization, integrated databases management and multi-media technologies, were presented. The initial pilot project of BJVSIS was finished successfully in 2001, and up to now this information system runs very well and plays a great role in the construction of the Virescence Separator. Just depended on the applications of so many high-tech like GIS, remote sensing, 3D visualization, and databases integration, BJVSIS can manage all kinds of relevant geographic data, such as vector graphics, DEM (Digital Elevation Model), image and multi-media attributes. And BJVSIS also provides many GIS functions, such as spatial query, 2D/3D display, spatial analysis, statistic calculation, form report and map output.

Phytoplasmas and rickettsias have been associated with recent nonviral papaya diseases (1,2). Forty leaf samples with symptoms similar to papaya bunchy top (PBT) (1) and Australian papaya diseases (2) were collected from surveys done in Cuban papaya areas of Havana and Villa Clara provinces. Thirty nine plants showed typical PBT symptoms, while 35 plants also exhibited symptoms previously described for phytoplasma diseases (2) such as yellowing, crinkling, necrosis and deformation of older leaves, phyllody, virescence, short internodes, reduced latex flow, stunted crown leaves, and abscission of the fruit. Samples were evaluated by transmission electron microscopy, nested polymerase chain reaction (nPCR) with 16S ribosomal RNA phytoplasma primers SN910601/DH6-R16F2n/R16R2, PCR with rickettsial succinate dehydrogenase gene (sdhA) primers PBT1/PBT2, HaeIII, RsaI, and AluI enzyme restriction, and phytoplasma intergenic sequence analyses. Rickettsia PCR amplifications of 750 bp were obtained for samples with PBT symptoms, while the 35 phytoplasma-infected samples yielded amplifications of 1,250 bp. Restriction profiles and a 98% homology in the intergenic sequence (GenBank Accession No. AY257547) confirmed the presence of apple proliferation phytoplasma group. Electron microscopy analysis evidenced the presence of particles similar to rickettsia and phytoplasma pleomorfic bodies in more than 50% of samples analysed. Also, those similar to potyvirus and rhabdovirus were observed in 22.5%. To our knowledge, these results are the first report on the molecular detection of phytoplasmas in papaya in Cuba and suggest a possible concomitance among phytopathogens detected. References: (1) M. Davis et al. Curr. Microbiol. 36:80, 1998. (2) K. Gibb et al. Plant Dis. 80:174, 1996.

Using direct and nested PCR technique followed by RFLP analysis, it was found that phytoplasmas were associated with Brassica napus plants showing symptoms such as phyllody, virescence, proliferation, flower sterility, from samples collected during a main survey carried out in different districts of Punjab, Pakistan. The samples from symptomatic plants were collected and observed by electron microscopy and tested using phytoplasma universal primer pairs R16F2n/R16R2, which confirmed the phytoplasma presence. Transmission trials by grafting and also by insects verify that the prokaryotes can be transmitted from diseased to healthy plants.

Phytoplasma symptomatology was observed in two periwinkle plants collected in a in commercial nursery in Campania Region (South Italy). The detected phytoplasmas were identified by RFLP analyses on amplicons and in silico as belonging to 16SrI-B subgroup (aster yellows). A multigene assays was performed to evaluate possible molecular diversity: the groEl gene characterization indicated that both strains are enclosed in subgroup groELI-III. The in silico RFLP analyses on tuf and rp genes allow to differentiate the two strains in periwinkle with Tsp509I endonuclease that produced unique profiles, clearly differentiating these from other phytoplasmas belonging to 16SrI-B subgroup. No differences were shown after RFLP analyses on SecY amplicons. Further work is in progress to evaluate the epidemiological relevance of these two aster yellows strains associated with virescence in periwinkle.

Sesame (Sesamum indicum L.) is an important oilseed crops widely grown in the southern regions of Turkey. Sesame seeds are primarily used in production of tahini as well as a garnish on sweets and bakery products in the country. Sesame plants with phyllody disease symptoms have increasingly been observed in the fields of Antalya province since 2007. The disease incidence in these fields was found to range from 37 to 62% (2). Infected plants display a variety of the disease symptoms such as virescence, asymptomatic shoot proliferation, infertile flower formation, reduced leaf size, and thin and weak capsule development. Total genomic DNA was extracted from samples collected from symptomatic (10 plants) and asymptomatic healthy-looking plants (10 plants) using a CTAB method and amplified with universal primers P1/P7 and R16F2n/R16R2 in direct and nested PCR, respectively (1,3). Amplifications of the DNA from the symptomatic plants yielded a product of 1.8 kb in direct and 1.2 kb in nested PCR assays. No amplification was observed in symptomless plants of the same age and collected from the same fields. Amplicons were purified, cloned in a pTZ57R/T Vector, and sequenced using a Beckman Coulter 8000 CEQ Genetic Analysis System. Four aligned 16S rDNA sequences (1,845 bp) were found to be all identical and belonging to one species. One sequence was deposited in GenBank under the accession number KC139791. A BLAST similarity search revealed that the sequence shared 99% homology with the sequences of the members of 16SrIX group phytoplasmas, ‘Brassica rapa’ phyllody phytoplasma (HM559246.1) and Iranian Almond witches'-broom phytoplasma (DQ195209.1) available in GenBank. In addition, iPhyClassifier software (4) was employed to create a virtual RFLP profile. The analysis showed that the RFLP profile of the sesame phytoplasma 16S rDNA sequence is identical (a similarity coefficient of 1.00) to the profile of the 16Sr group IX phytoplasma reference sequence (Y16389). A phylogenetic tree was also constructed using the neighbor joining plot option of the Clustal X program. The sequence clustered together with 16SrIX group phytoplasmas. To our knowledge, this is the first report of a natural infection of sesame by a new phytoplasma species from the 16SrIX group in Turkey. References: (1) D. E. Gundersen and I.-M. Lee. Phytopathol. Mediterr. 35:144, 1996. (2) C. Ikten et al. Phytopathogenic Mollicutes 1:101, 2011. (3) C. D. Smart et al. Appl. Environ. Microbiol. 62:2988, 1996. (4) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.

Dans les vergers agrumicoles de la vallée de Nayron (sud ouest d'Arabie Saoudite), le greening constitue un risque potentiel du fait de sa présence dans les pays d'Asie et en Afrique. Mais le climat de Nayran caractérisé par une faible évapotranspiration empêche le développement des homoptères psyllidés (Trioza erytreae) vecteurs des pathogènes responsables du greening. En revanche, les conditions hygrométriques sont favorables dans les pépinières du fait de l'irrigation. D'où l'étude de survie et de l'infection des plants en pépinière entreprise afin d'évaluer les risques de contamination. Au champ, le diagnostic du greening est aléatoire puisqu'aux symptômes habituels se combinent les effets du déficit en eau et de la salinité

Ten species of herbaceous plants and shrubs with MLO symptoms such as stunting, bushing, yellowing, reddening, virescence or phyllody were collected in both grapevine yellows (GY)-infected and uninfected vineyards. By electron microscopy, MLOs were found in the sieve tubes of eight species. The presence of MLOs in Picris echioides is demonstrated for the first time. The possible role of MLO-infected weeds in the spread of GY disease is discussed.

Arnica montana L. is a high altitude perennial plant, indigenous to Europe, but it is not native in the flora of Serbia. Plantain introduction of A. montana began a few years ago in the Tara mountain region, Western Serbia (43°53′44.17″N 19°33′11.62″E, 1,008 m ASL). The mountainous climate in this region is characterized by 850 mm of precipitation per year and an average decade temperature range from 11 to 25°C in the vegetation period of May through September. The main soil type is dystric cambisol, exhibiting a slightly acidic reaction (pH 6.4). Seeds of A. montana cv. ARBO were obtained from the Agricultural Research Centre of Finland. Seedlings were produced in a greenhouse during the period March through April and planted in May 2008. Virescence symptoms were observed starting from May 2010. A. montana exhibited symptoms mainly on flowers, like green leaflike structures instead of flowers and proliferation of acillary buds. Later in the season, flowers were malformed and consequently failed to produce seeds. Plant material for analyses was collected during 2010 and 2011 from an experimental field located at Tara mountain. Total DNA was extracted from the leaf midveins of 14 symptomatic and six symptomless plants (3). Nested PCR was carried out with primers P1/P7 followed by P1/16S-Sr and R16F2n/R16R2 primers, resulting with the DNA fragments amplification of expected size: 1.8, 1.5, and 1.2 kb, respectively, in all symptomatic samples tested. No phytoplasmas were detected in symptomless samples. PCR products of 1.2 kb, obtained by R16F2n/R16R2 primers from symptomatic samples, were digested independently with four restriction enzymes (Alu I, Tru I, Hpa II and Hha I) and the RFLP patterns were compared with those of Stolbur (Stol), Aster Yellows (AY), Flavescence Doree-C (FD-C), Poinsettia Branch-Inducing (PoiBI) and Clover Yellow Edge (CYE) phytoplasmas (2). RFLP patterns from all symptomatic A. montana samples were identical to CYE pattern. Comparison of the 16S rDNA sequence of representative symptomatic sample Am4, deposited under accession number JX297491 in NCBI GenBank, with other phytoplasmas from the database revealed 99% identity with members of 16SrIII-B phytoplasma group: Clover yellow edge phytoplasma strain CYE (JQ944798.1), ‘Euscelidius variegatus’ phytoplasma strain AP-I (HQ589197.1), Clover phyllody phytoplasma strain CP (HQ589196.1), etc. In Serbia, phytoplasma belonging 16SrIII-B subgroup has been identified in Cirsium arvense (4) and pear plants (1). To our knowledge, this is the first report of a natural infection of A. montana by phytoplasma. Cultivation of A. montana provides the necessary raw material for medicament production. The flower heads are widely used for the topical treatment of bruises and sprains in phytopharmaceutical preparations.Taking into consideration that monoculture plantation growing of perennials favorites rapid spreading of infections, the present study tended to examine the potential threat of virescence, which could be the limiting factor of ex-situ conservation of this endangered plant by its cultivation. References: (1) B. Duduk et al. Acta Hortic. 781:351, 2008. (2) I. M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998. (3) J. P. Prince. Phytopathology 83:1130, 1993. (4) D. Rancic et al. Plant Pathology 54:561, 2005.

Soybean (Glycine max L.) is an important grain legume cultivated on approximately 1.24 million ha in Africa (1). Malawi ranks fourth in area of production in Africa, with 75,000 ha in 2009 (1). Soybean is also gaining importance in Mozambique and several other southern African countries due to diversification programs. During a field survey conducted in March 2010, soybean plants with phyllody and witches'-broom disorders typical of phytoplasma infection were observed in three of five fields surveyed in Lilongwe (Chitedze Research Station) and Salima (Channa, Chitala) districts in Malawi and three of four fields surveyed in Zambezia Province in Mozambique. Symptoms consisted of shoot proliferation, reduced leaflets, shortened internodes, proliferated auxiliary shoots producing witches'-brooms, virescence, and phyllody. Incidence of symptomatic plants was References: (1) FAOSTAT. http://faostat.fao.org/site/567/default.aspx . Retrieved 28 December 2010. (2) P. Plumb-Dhindsa and A. M. Mondjane. Trop. Pest Manage. 30:407, 1984. (3) L. B. Sharmila et al. J. Plant Biochem. Biotech. 13:1, 2004. (4) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.