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Quantitative PCR (qPCR), loop-mediated amplification (LAMP), and lateral flow strip-based recombinase polymerase amplification (RPA-LFS) assays were assessed for early detection of Phytophthora infestans, the global causal agent of potato and tomato late blight, on passive wind-powered spore traps known as Spornados. Spore traps were deployed in potato and tomato fields during the 2018, 2019, and 2020 growing seasons in the provinces of Alberta, British Columbia, Manitoba, Prince Edward Island, and Ontario. All assays used DNA extracts from Spornado cassette membranes targeting the P. infestans nuclear ribosomal internal transcribed spacer. A total of 1,003 Spornado samples were qPCR tested, yielding 115 positive samples for P. infestans spores. In further assessment of these samples, LAMP detected P. infestans in 108 (93.9%) of 115 qPCR positive samples, and RPA-LFS detected it in 103 (89.6%). None of the assays showed cross-reaction with other Phytophthora species or pathogenic fungi known to infect potato and tomato. The qPCR detected ≤1 fg of P. infestans DNA, and LAMP and RPA-LFS amplified 10 fg in as little as 10 min. All assays detected P. infestans before the first report of late blight symptoms in commercial potato or tomato fields within each region or province. The combination of Spornado passive samplers with qPCR, LAMP, or RPA-LFS proved a valuable spore trapping system for early surveillance of late blight in potato and tomato. Both LAMP and RPA-LFS showed potential as alternative approaches to qPCR for in-field monitoring of P. infestans.

The genus ‘Candidatus Phytoplasma’ was proposed to accommodate cell wall-less bacteria that are molecularly and biochemically incompletely characterized, and colonize plant phloem and insect vector tissues. This provisional classification is highly relevant due to its application in epidemiological and ecological studies, mainly aimed at keeping the severe phytoplasma plant diseases under control worldwide. Given the increasing discovery of molecular diversity within the genus ‘Ca. Phytoplasma’, the proposed guidelines were revised and clarified to accommodate those ‘Ca. Phytoplasma’ species strains sharing >98.65 % sequence identity of their full or nearly full 16S rRNA gene sequences, obtained with at least twofold coverage of the sequence, compared with those of the reference strain of such species. Strains sharing 98.65 % with other strain(s) within the same ‘Ca. Phytoplasma’ species should be considered related strains to that ‘Ca. Phytoplasma’ species. The guidelines herein, keep the original published reference strains. However, to improve ‘Ca. Phytoplasma’ species assignment, complementary strains are suggested as an alternative to the reference strains. This will be implemented when only a partial 16S rRNA gene and/or a few other genes have been sequenced, or the strain is no longer available for further molecular characterization. Lists of ‘Ca. Phytoplasma’ species and alternative reference strains described are reported. For new ‘Ca. Phytoplasma’ species that will be assigned with identity ≥98.65 % of their 16S rRNA gene sequences, a threshold of 95 % genome-wide average nucleotide identity is suggested. When the whole genome sequences are unavailable, two among conserved housekeeping genes could be used. There are 49 officially published ‘Candidatus Phytoplasma’ species, including ‘Ca. P. cocostanzaniae’ and ‘Ca. P. palmae’ described in this manuscript.

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Over 360 Hemiptera specimens were collected using sweep nets and hand-made aspirators from coconut palm fronds in six villages of Grand-Lahou. Eight families were identified including Aphrophoridae, Achilidae, Derbidae, Flatidae, Membracidae, Pentatomidae, Tropiduchidae, and Cicadellidae, the latter being the most abundant throughout the surveyed villages. PCR assays with primers targeting the 16S rRNA and the secA translocation protein genes yielded PCR amplicons from 216 out of 296 (73%) of the tested specimens of a newly identified cicadellid leafhopper, Nedotepa curta Dmitriev. PCR amplicons were purified, cloned and sequenced. The 16S rDNA and secA sequences from N. curta showed a 99% of sequence identity with those of the Cote d’Ivoire lethal yellowing (CILY) phytoplasma, member of subgroup 16SrXXII-B ‘Candidatus Phytoplasma palmicola’-related strain, previously identified in coconut-growing villages of Grand-Lahou. This suggested N. curta as a potential vector for the CILY phytoplasma. Four symptomatic coconut palms (7.4%) were found infected by a phytoplasma of group 16SrI, in mixed infection with the CILY phytoplasma (16SrXXII-B) in two palms, and alone in the other two palms, where the CILY phytoplasma was not detected. The 16SrI phytoplasma was also found in two N. curta specimens, and in the weeds Dalbergia saxatilis and Baphia nitida. Results indicating that mixed infection of both 16SrXXII-B and 16SrI phytoplasmas occurs in coconut palms affected by CILY in Grand-Lahou, and may impact disease management and control.

The diversity of culturable bacterial and fungal communities was assessed from leaves, trunk and rhizosphere of coconut palms infected and non-infected by the Cote d’Ivoire lethal yellowing (CILY) phytoplasma. Bacterial and fungal microbes were isolated from leaves, trunk and rhizosphere samples collected from two villages of Grand-Lahou, Braffedon and Yaokro, by using a high-throughput 'dilution-to-extinction' cultivation method coupled with PCR and sequencing with primers that amplified both the 16S ribosomal RNA and intergenic transcribed spacer (ITS) genes. The relative abundance was higher for Bacillus and Candida in Braffedon, and Burkholderia and Neodeightonia in Yaokro. Commonly genera identified from rhizosphere included Bacillus, Burkholderia, Pseudomonas, Streptomyces, Cryptococcus, Penicillium, Purpureocillium and Trichoderma. The most abundant endophytes identified were Pantoea, Candida, Cryptococcus, Bacillus, Pseudomonas, Penicillium, Aspergillus and Rhodotorula. Genera limited to symptomless palms included Arthrininum, Chaetomium, Phialemonium, Fusarium, Klebsiella and Candida. Results indicate that the CILY phytoplasma may be a factor determining the level of diversity of a microbial community in a given location. Our research provides the basis to investigate the possible effect of endophytic and rhizosphere microbes against the CILY phytoplasma to further effectively improve the management of CILY in Grand-Lahou. Key words: Cote d’Ivoire lethal yellowing phytoplasma, endophytes, biocontrol, coconut.

Surveys for the Cote d'Ivoire lethal yellowing (CILY) phytoplasma were conducted in eight severely CILY-affected villages of Grand-Lahou in 2015. Leaves, inflorescences and trunk borings were collected from coconut palms showing CILY symptoms and from symptomless trees. Total DNA was extracted from these samples and tested by nested polymerase chain reaction/RFLP and sequence analysis of the 16S rRNA, ribosomal protein (rp) and the translocation protein (secA) genes. The CILY phytoplasma was detected in 82.9% of the symptom-bearing palms collected from all the surveyed villages and from all the plant parts. Trunk borings were recommended as the most suitable plant tissue type for sampling. Results indicate that the CILY phytoplasma may have a westward spread to other coconut-growing areas of Grand-Lahou. CILY phytoplasma strains infecting coconut palms in the western region of Grand-Lahou exhibited unique single nucleotide polymorphisms on the rp sequence compared to the strains from the eastern region. Moreover, single nucleotide polymorphisms on the SecA sequence distinguished the CILY phytoplasma from the Cape St. Paul Wilt Disease phytoplasma in Ghana, and the Lethal Yellowing phytoplasma in Mozambique. (Resume d'auteur)

Surveys for phytoplasmas and viruses were conducted during September 2014 and 2015 on highbush blueberry farms in the Région Montérégie, Quebec. Total DNA and RNA were extracted from blueberry bushes showing blueberry stunt (BBS) symptoms and from symptomless blueberry bushes, and utilised as templates for PCR and RT-PCR assays, respectively. Phytoplasma DNA was amplified with universal phytoplasma primers that target the 16S rRNA, secA and secY genes from 12 out of 40 (30%) plants tested. Based on 16S rRNA, secA and secY gene sequence identity, phylogenetic clustering, actual and in silico RFLP analyses, phytoplasma strains associated with BBS disease in Quebec were identified as ‘Candidatus Phytoplasma asteris’-related strains, closely related to the BBS Michigan phytoplasma strain (16SrI-E). The secY gene sequence-based single nucleotide polymorphism analysis revealed that one of the BBS phytoplasma strains associated with a leaf marginal yellowing is a secY-I RFLP variant of the subgroup 16SrI-E. Two viruses were detected in blueberry bushes. The Blueberry Red Ringspot Virus (BRRV) was found in a single infection in the cultivar Bluecrop with no apparent typical BRRV symptoms. The Tobacco Ringspot Virus (TRSV) was found singly infecting blueberry plants and co-infecting a BBS phytoplasma-infected blueberry cv. Bluecrop plant. This is the first report of TRSV in the cv. Bluecrop in Quebec. The Quebec BBS phytoplasma strain was identified in the leafhopper Graphocephala fennahi, which suggests that G. fennahi may be a potential vector for the BBS phytoplasma. The BBS disease shows a complex aetiology and epidemiology; therefore, prompt actions must be developed to support focused BBS integrated management strategies.

Cote d'Ivoire lethal yellowing (CILY) is a devastating disease associated with phytoplasmas and has recently rapidly spread to several coconut-growing areas in the Country. Phytoplasmas are phloem-restricted bacteria that affect plant species worldwide. These bacteria are transmitted by plant sap-feeding insects, and their cultivation was recently achieved in complex artificial media. In this study, phytoplasmas were isolated for the first time from coconut palm trunk borings in both solid and liquid media from CILY symptom-bearing and symptomless coconut palms. The colony morphology, PCR and sequencing analyses indicated the presence of phytoplasmas from different ribosomal groups. This study reports the first biochemical characterization of two of these phytoplasma isolates. Moreover, a disc-diffusion antibiotic susceptibility assay revealed that these bacteria exhibit tobramycin susceptibility and cephalexin hydrate and rifampicin resistance. Urea and arginine hydrolysis, and glucose fermentation tests that were performed on colonies of phytoplasmas and Acholeplasma laidlawii indicated that both phytoplasmas tested were negative for urea and positive for glucose and arginine, whereas A. laidlawii was positive for glucose and negative for urea and arginine. The growth of coconut phytoplasmas in both solid and liquid artificial media and the biological characterization of these isolates are novel and important advancements in the field of disease management and containment measures for the CILY disease. The characterization of isolated phytoplasmas will allow for more efficient management strategies in both the prevention of a coconut phytoplasma epidemics and the reduction of the economic impact of the disease in the affected areas.

ʻCandidatus Phytoplasma asterisʼ (CPa) has been identified along with ʻCandidatus Liberibacter asiaticusʼ (CLas) from citrus trees showing Huanglongbing (HLB) symptoms in Mexico. The low titre of CPa and CLas in infected plants is the major constraint to developing an accurate and sensitive method for their detection that would support an effective HLB diagnosis and management programme. This investigation reports the development and validation of a new TaqMan quantitative PCR to detect low titres of CPa in citrus trees with HLB symptoms based on the phytoplasma 16S rRNA gene region. The assay was used to monitor the titre of CPa at early and late stages of disease development in symptomatic and asymptomatic Mexican lime trees in Colima, Mexico. The concentration of CLas was determined by nested-qPCR. Only eight out of 39 sampled branches showed HLB symptoms at the early infection stage. All 39 branches were symptomatic at the late infection stage. The qPCR yielded an increase in the branch incide...

Palms are native to tropical and subtropical areas of the world and con-tribute to the ecology and economy of many countries. Phytoplasmas which are cell-wall-less prokaryotes are associated with diseases of significant economic importance to palms worldwide. The diseases are vectored by insects, such as Haplaxius crudus, which transmits the lethal yellowing phytoplasma in Florida. In other places, such as in Africa, the vectors have so far been elusive, although puta-tive vectors have been identified. Management of these palm diseases relies on inte-grated approaches involving the use of resistant materials and cultural methods such as early detection and removal of affected palms. The gaps in the present knowledge of the diseases provide excellent opportunities for further research on these enig-matic plant pathogens.

Coconut palms from the Grand-Lahou region of Cote d’Ivoire exhibiting lethal yellowing-like symptoms and infected by a phytoplasma were further tested for the characterization of the phytoplasma pathogen based on the 16S rRNA gene analysis. Nested PCR with phytoplasma universal and lethal yellowing-specific primers resulted in amplification of products of expected sizes from seven out of 17 symptomatic trees tested, while non-infected symptomless plants yielded no DNA amplification. The 16S rDNA sequence of the phytoplasma detected from Grand-Lahou in coconut trees (KC999037) affected with the Cote d’Ivoire Lethal Yellowing disease showed a 99% sequence identity with that of the Ghanaian lethal yellowing phytoplasma (Cape St. Paul Wilt strain) of group 16SrXXII. The 16S rDNA sequence-based virtual and actual RFLP and phylogenetic analyses revealed that the phytoplasma associated with Cote d’Ivoire Lethal Yellowing in Grand Lahou is as a member of a new subgroup within group 16SrXXII that was desig...

Prunus and Pyrus species affected with phytoplasma diseases, as well as leafhopper species collected from Prunus and Pyrus fields in Ontario, Canada were tested for presence of phytoplasmas. Preliminary results showed that Graminella nigrifrons is a potential vector for phytoplasma groups 16SrI-W (‘Candidatus Phytoplasma asteris’), and 16SrVII-A (‘Candidatus Phytoplasma fraxini’) to a variety of plant hosts, including peach, apricot, plum and pear. Results showed that G. nigrifrons may be able to transmit both phytoplasma groups simultaneously within the same location and suggest that G. nigrifrons populations appear to have a complex ecology.

Peach trees exhibiting peach rosette-like disease symptoms and infected by a phytoplasma of group 16SrI ‘Candidatus Phytoplasma asteris’ at the Canadian Clonal Genebank were further tested for the pathogen characterization based on the 16S rRNA gene. Nested PCR with phytoplasma universal primers R16mF2/R1 and R16F2n/R2 resulted in amplification of products of approximately 1.25 kb from all four symptomatic trees tested. Virtual RFLP of the R16F2n/R2 sequenced amplicons with selected restriction endonucleases showed unique RFLP patterns when compared to the described 16SrI phytoplasma subgroups; these data were confirmed by phylogenetic analyses. The phytoplasma was therefore assigned as a member of a new 16SrI subgroup (16SrI-W). Results represent the first report of a new phytoplasma 16SrI subgroup infecting peach in Canada, and provide a valuable tool for further epidemiological studies on this phytoplasma in peach.

A new Afrotropical species of Anagrus Haliday (Hymenoptera: Mymaridae), A. nedotepae Triapitsyn sp. n., is described and illustrated. The type series was reared from parasitized eggs of the leafhopper Nedotepa curta Dmitriev (Hemiptera: Cicadellidae) during a survey for its natural enemies in Côte d’Ivoire. This peculiar leafhopper, recently described from Ghana (Dmitriev 2016), lays its eggs on leaflets of coconut palm, and could be an economically important pest of this crop in West Africa, particularly because it is a suspected vector of the phytoplasma associated with the Côte d’Ivoire Lethal Yellowing disease of coconut, as characterized by Arocha-Rosete et al. (2014). Coconut lethal yellowing diseases cause severe economic losses to the very important coconut growing industry in several West African countries and elsewhere, being considered a threat of global economic and social significance (Gurr et al. 2016). Thus, the parasitoid may be of potential importance for natural biological control of this pest and urgently needs a scientific name to be used in further publications on its biology and ecology. Such studies are currently underway by the second author, who collected the type series of the new species.

Cassava in Cote d'Ivoire is currently threaten by the Cote d'Ivoire lethal yellowing disease (CILY), which destroyed over 400 ha of coconut plantations in Grand-Lahou. Due to CILY impact in coconut farms, women coconut farmers planted cassava plots in coconut lands devastated by the disease. Symptoms of leaf mosaic, curling and yellowing were observed in cassava plots after one and a half year from planting. Leaf samples were collected from symptom-bearing and symptomless cassava plants in two coconut-growing villages of Grand-Lahou, and subjected to total DNA extraction. Samples were PCR tested using phytoplasma 16S rRNA universal primers, as well as primers specific for subgroup 16SrXXII-B, ‘Candidatus Phytoplasma palmicola-related strains’, and for African/East African cassava mosaic viruses (ACMV, EACMV). Six out of 12 symptom-bearing samples showed PCR amplicons, five of which co-amplified for viral DNA. Phytoplasma sequences, RFLP and phylogenetic analyses confirmed the identification of phytoplasmas of subgroup 16SrXXII-B in co-infection with ACMV in one cassava plant sample, while either ACMV or EACMV were detected in other four cassava plant samples. Cassava was confirmed as a potential alternative host for the CILY phytoplasma, which may play a role in spreading and worsening the severity of CILY disease in coconut palms. The presence of begomoviruses in mixed infection with the CILY phytoplasma in cassava may increase the difficulty of CILY management and control, and poses a serious food security threat for the livelihoods of smallholder farmers in Grand-Lahou.

Trillium (family Melanthiaceae) is a genus of perennial flowering plants native to temperate regions of North America and Asia, and traditionally used as medicinal plants (Case, 2000). There are 49 species within the genus Trillium amongst which the white trillium, T. grandiflorum serves as the emblem and official flower of the Canadian province of Ontario. Other species include T. erectum, also known as red trillium. Many of these plants are adapted to conditions found in suburban or rural gardens. Compared with symptomless plants (Fig. 1), plants of T. grandiflorum and T. erectum with symptoms of virescence typical of phytoplasma infection (Figs. 2-3) were observed growing as weeds on a private property in the Sparta area of London, Ontario in May 2016 Plants were removed by the owner, placed in plastic bags and transported to the laboratory in ice coolers. Leaves, petioles and flowers were excised from eight symptom-bearing and two symptomless plants of each species. Total DNA was extracted and used as a template for a nested PCR assay with universal primers that target the phytoplasma 16S rRNA gene, R16mF2/R1 for the first PCR reaction, and R16F2n/R2 for the nested reaction (Gundersen & Lee, 1996). All samples from symptom-bearing plants yielded R16F2n/R2 amplicons. No PCR amplicons were obtained from the symptomless plants. One R16F2n/R2 amplicon from T. grandiflorum and three from T. erectum were purified (EZNA Cycle Pure Kit, Omega Bio-Tek, USA), cloned (pGEM-T Easy Vector, Promega) and sequenced (University of Toronto, Canada). Sequences were compared with those of phytoplasmas in NCBI. Sequences from T. grandiflorum (Genbank Accession No. KX470428) and T. erectum (KX470427, KX470429 and KX470430) shared over 99.7% sequence identity and were 99% similar to those of phytoplasma members of the group 16SrIII (Western X-disease). Phylogenetic analysis (using MEGA v4.0) of the 16S rDNA sequence (Fig. 4) supported the grouping of the phytoplasma isolated from both T. grandiflorum and T. erectum plants as a 'Candidatus Phytoplasma pruni'-related strain, with 99% sequence identity o the reference strain for the species (Milkweed yellows phytoplasma, 16SrIII-F, HQ589200). No phytoplasmas have been reported from Trillium plants in Canada. The X-disease (group 16SrIII) was first reported in 1941 in Ontario in the Niagara peninsula (Stevens & Stevens, 1947). In 1971, peach X-disease was detected in Essex County (Dhanvantari & Kappel, 1978) affecting more than 50% of peach orchards. In North America, phytoplasmas of the 16SrIII group are associated with several diseases in cherry and peach (Scott & Zimmerman, 2001). The presence of a 'Ca. P. pruni'-related strain in Trillium not only poses a threat for T. grandiflorum as a protected species, and other Trillium species in Ontario, but also for other plant species grown nearby. To our knowledge, this is the first detection of a phytoplasma in Trillium species in Canada and worldwide.

Peach (Prunus persica), family Rosaceae, is native to China. In Canada, the province of Ontario produces 82% of the nation’s peach crop. The Canadian Clonal Genebank, also located in Ontario, currently holds 83 accessions of peach. The collection is routinely monitored for symptoms of phytoplasma including decline (Fig. 1), leaf reddening (Fig. 2), yellowing, shortening of internodes, witches’ broom and reduced fruit size. Leaf samples from trees exhibiting symptoms and symptomless trees representing sixteen accessions were collected from June to August 2009. Total DNA was extracted (DNeasy plant extraction kit, QIAGEN). Phytoplasma universal primers specific for 16S rDNA (R16mF2/R1 and R16F2n/R2; Gundersen & Lee, 1996) were used in a nested PCR assay. Nested PCR products of expected size (~1250 bp) were obtained for accessions PRU0430 (cv. HW274, from Canada), PRU0380 (cv. GF 305 from France), PRU0334 (cv. RedSkin from USA), PRU0155 (cv. Harblaze from Canada) and PRU0375 (cv. Babygold #5 from USA). Symptomless plants yielded no PCR products. Amplicons were purified (Wizard PCR Clean-up, Promega), cloned (pGEM-T Easy Vector, Promega), and sequenced (Robarts Institute, London, Canada). The obtained sequences shared 100% identity with each other and a representative corresponding to PRU0430 was deposited in GenBank (Accession No. GU223903). BLAST analysis showed that the Prunus phytoplasma shared 99% 16S rDNA sequence identity with those of phytoplasmas in the group 16SrVII (ash yellows) for which ‘Candidatus Phytoplasma fraxini’ is the reference strain. Restriction fragment length polymorphism analysis (RFLP) of amplicons using AluI, RsaI and MseI yielded profiles similar to those of 16SrVII-A phytoplasma subgroup. Phytoplasmas of group 16SrVII have been reported in different hosts in Colombia, Argentina, Brazil and Chile (Fiore et al., 2007). Particularly in North America, including Canada, 16SrVII phytoplasmas have been associated with ash yellows and lilac witches’ broom diseases (Sinclair et al., 1996; Griffiths et al., 1999). To our knowledge, this is the first report of a 16SrVII-related phytoplasma strain identified in peach after an incidental report in peach in Southern Italy (Paltrineri et al., 2003). The 16SrVII phytoplasma has caused devastating effects in ornamentals. Therefore its presence in peach is of great phytosanitary significance due to its commercial interest, and represents a potential threat for disease spread to other fruit crops, particularly Prunus sp.

Prunus persica (L.) Bastch (family Rosaceae) is currently represented by 83 accessions at the Canadian Clonal Genebank. Approximately 3,200 ha are devoted to peach cultivation in Canada where Ontario Province accounts for 82% of the national production. The clonal peach accessions, also located in Ontario, are monitored routinely for symptoms of phytoplasma infection, including rosette-like symptoms (3) that are characterized by new shoots with very short internodes, loss of older shoot leaves leaving only bunches of young leaves on the tips of naked shoots, and flowers that rarely set fruit. From June to August 2009, peach accessions PRU0382 and PRU0445 showed typical peach rosette symptoms, while another 14 accessions exhibited either short internodes or no symptoms. Leaf midrib samples were collected from 16 peach accessions, including 17 symptomatic (from which 8 corresponded to accession PRU0382, 6 for PRU0445, 1 for PRU0335, 1 for PRU0179, and 1 for PRU0451) and 16 asymptomatic (from which 5 corresponded to a representative of each accession PRU0382, PRU0445, PRU0335, PRU0179, and PRU0451 and 11 to other peach accessions). Total DNA was extracted (DNeasy Plant Extraction Mini Kit, QIAGEN, Valencia, CA) from 100 mg of each sample and used as a template in a nested PCR with phytoplasma universal primers R16mF2/R1 (1) and fU5/rU3 (2). Nested PCR products of the expected size (~880 bp) were obtained from all symptomatic samples (14 of 14) of accessions PRU0382 (peach-almond cv. Kando from the Czech Republic) and PRU0445 (peach cv. HW271 from Canada) only. All other plants with or without symptoms yielded no PCR products. Amplicons were purified (Wizard PCR Clean-up, Promega, Madison, WI), cloned in pGEM-T Easy Vector (Promega), and sequenced (Robarts Institute, London, Canada). The resulting 16S rDNA sequences were identical; one of each was archived in GenBank as Accession No. GU223904. BLAST analysis determined that the P. persica phytoplasma sequence shared 99% identity with 16S rDNA sequences of ‘Candidatus Phytoplasma asteris’-related strains. This relationship was also supported by restriction fragment length polymorphism analysis (RFLP) of rDNA amplicons using AluI, RsaI, and MseI endonucleases that yielded fragment profiles indicative of phytoplasmas belonging to group 16SrI (Aster Yellows), subgroup B (16SrI-B). Among phytoplasma diseases, those attributed to group 16SrI strains are most numerous and affect the widest plant host range. They include peach rosette in the United States and Europe (3) as well as diseases of various horticultural crops in Canada, including grapevine (4). To our knowledge, this is the first report of a subgroup 16SrI-B phytoplasma affecting peach in Canada. Early detection of phytoplasmas by PCR in accessions with both European and Canadian origins underscores the importance of prompt identification of infected plants for subsequent thermotherapy treatment to maintain the health of the collection and prevent further disease spread. References: (1) D. E Gundersen and I.-M. Lee. Phytopathol. Mediterr. 35:1441, 1996. (2) K. H. Lorenz et al. Phytopathology 85:771, 1995. (3) C. Marcone et al. Acta Hortic. 386:471, 1995. (4) C. Y. Olivier et al. Plant Dis. 93:669, 2009.

Transmission tests were conducted with field-collected Bunchy Top Symptoms (BTS) phytoplasma-infected specimens of Entpoasca papayae. BTS developed in all eight inoculated papayas 3 months later. The BTS phytoplasma was identified in six of eight inoculated papayas, whose partial 16S rRNA sequence (GenBank Accession no. FJ6492000) was 99.9% identical with those from the collected papayas (GenBank Accession no FJ649198) and E. papayae (GenBank Accession no. FJ649199), all of which are members of group 16SrII, 'Candidatus Phytoplasma aurantifolia'. Results confirmed the ability of E. papayae to transmit the BTS phytoplasma.

Blueberry farms in Quebec, Canada, were recently surveyed for phytoplasma-associated disease presence. Farmers previously reported a number of high bush blueberries showing stunt symptoms in three blueberry farms. Bushes were tested for phytoplasma based on the 16S rRNA gene. Nested PCR with universal phytoplasma primers resulted in amplification of phytoplasma DNA from blueberry bushes in samples from two of the farms surveyed. The 16S rDNA of the blueberry stunt phytoplasma from Quebec showed a 99% sequence identity with that of the blueberry stunt phytoplasma from Michigan (AY265220) from group 16SrI ‘Candidatus Phytoplasma asteris’ subgroup 16SrI-E. Phylogeny results confirmed the clustering of the blueberry stunt phytoplasma from Quebec within the same phylogenetic branch of phytoplasmas of group 16SrI, closely related to subgroup 16SrI-E. Preliminary virtual RFLP confirmed the sequence and phylogeny classification results. Further actual and virtual analyses are in progress to verify the presence of other possible phytoplasma strains from the Quebec blueberry farms.

Cocos nucifera is considered the most important crop along the coastal belt of West Africa. Particularly in Cote d'Ivoire, coconut palm is cultivated on approximately 50,000 ha (Konan et al. , 2008) and produces an average of 45,000 tonnes…