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Recently, grapevine trunk diseases have been considered the most destructive of grapevine species in Morocco. Several damages are observed annually in vineyards by these destructive diseases in vineyards. Botryosphaeria dieback is one of the major responsible of these wasting diseases. Symptoms include sectorial and central necrosis, brown bands or cracks, discolorations and withering on the foliar surface. Botryosphaeria dieback symptomatology, associated fungi, host-pathogen interaction, and control methods are the topics of this review. [ABSTRACT FROM AUTHOR]

Grapevine trunk diseases can infect nursery plants at different stages of propagation. Here, we evaluated the efficiency of aqueous ozone against two fungi associated with trunk diseases (Phaeoacremonium minimum and Phaeomoniella chlamydospora). The effect of ozone on the plant growth is also studied. Aqueous ozone completely suppressed spore germination in vitro. In planta fungal development was reduced six weeks post-inoculation. In the nursery, ozone treatment was comparable to the usual chemical treatment. Irrigation with aqueous ozone had no negative effects on plant growth. These anti-fungal properties and the absence of phytotoxicity make ozone a promising alternative for controlling microbial infection in nurseries. [ABSTRACT FROM AUTHOR]

Fatty acid methyl ester (FAME) analyses can be useful for distinguishing microbial species. This study conducted FAME analyses on 14 fungal species known to cause grapevine trunk diseases. FAME profiles were dominated by oleic acid, albeit profiles were characteristic enough to separate species. Discriminant analyses suggested that palmitoleic acid/sapienic acid, pentadecylic acid, and an unsaturated 17-carbon fatty acid (17:1ω8 c)could explain 79.8% of the variance in the profiles among species in the first three discriminant functions. FAME profile libraries were created for use in a commercialized software, which was able to accurately identify isolates to the species level, with a low rate (9.4%) of samples to be reassessed. Dendrograms created using neighbor-joining cluster analyses with data from FAME profiles were compared with those using internal transcribed spacer (ITS) region sequences. This revealed that FAME profiles, albeit useful for tentative species identification, should not be used for determining phylogenetic relationships because the dendrograms were significantly unconcordant. Regardless, these results demonstrated the potential of FAME analyses in quickly and initially identifying closely related fungal species or confirming conclusions from other species identification techniques that would require independent validation. [ABSTRACT FROM AUTHOR]

Two known viruses are blueberry scorch virus (BlScV, genus I Carlavirus i ) and blueberry shock virus (BlShV, genus I Ilarvirus i ), both commonly found on BC blueberry farms. I Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada; and (E.G.) British Columbia Blueberry Council, #275 - 32160 South Fraser Way, Abbotsford, BC V2T 1W5, Canada i One of British Columbia's (BC) most valuable crops is blueberry ( I Vaccinium corymbosum i ). Department of Biology, University of British Columbia - Okanagan, Kelowna, BC V1V 1V7, Canada i I Phaeomoniella chlamydospora i is one of the main causal agents of Petri disease, which primarily affects young grapevines and is part of the grapevine trunk diseases complex. I Department of Forest and Conservation Sciences, University of British Columbia, 2424 Main Mall, BC V6T 1Z4, Canada i Aggressive plant pathogens alter forest stand structure and composition, ecosystem services, and trophic cascades. [Extracted from the article]

Several virus diseases cause damage to Vitis vinifera L., but information on their incidence and impact on hybrid cultivars is scarce, particularly under cool-climate conditions. In Nova Scotia (NS), the wine industry is based predominantly on interspecific hybrid cultivars. To understand the occurrence of major grapevine viruses in NS, surveys were conducted in 2016, 2017 and 2018. A total of 965 composite five-vine samples, collected from 35 hybrids and 18 V. vinifera vineyard blocks, were tested for grapevine leafroll-associated virus 1 (GLRaV-1), GLRaV-2, GLRaV-3 and GLRaV-4, grapevine fanleaf virus (GFLV), grapevine red blotch virus (GRBV) and grapevine Pinot gris virus (GPGV) by PCR/RT-PCR. Overall, 3.4% of the samples were positive for GLRaV-1, 22.8% for GLRaV-3, 0.9% for GFLV, 4.6% for GRBV and 3.2% for GPGV. None of the 575 samples collected in 2016 and 2017 tested positive for GLRaV-2 or GLRaV-4. Mixed infections by more than one virus occurred in 3% of the composite samples. Of 671 hybrid and 294 V. vinifera samples tested, 38.3% and 27.6% were positive for at least one of the viruses (GLRaV-1, −3, GFLV, GRBV and GPGV), respectively. Phylogenetic analysis of GLRaV-1, −3, GFLV and GPGV revealed the presence of global variants. Complete genome characterization and phylogenetic analysis of nine GRBV isolates grouped three into clade I and six into clade II, indicating the presence of two variants. These findings, along with preliminary reports of insect vectors, establish the first epidemiological framework of the major viral diseases in NS, highlighting the need for long-term management strategies. [ABSTRACT FROM AUTHOR]

Grapevine trunk diseases (GTDs), caused by a complex of fungi, are a global threat to vineyard longevity. Identifying the fungi in each growing region is crucial for interpreting symptoms and understanding disease progression. Despite considerable research, the spectrum of fungi involved in GTDs in New Zealand remains uncertain and species identities within key taxonomic groups require validation with molecular sequences. We provide a synopsis of fungi from known pathogenic GTD taxa that have been identified in culture-dependent studies in New Zealand, especially those accessible through culture collections such as the International Collection of Microorganisms from Plants (ICMP). Results from a 2007–2010 countrywide vineyard survey for GTD fungi are presented, plus new isolates and associated DNA sequences from a 2017 survey of Marlborough and Hawke's Bay vineyards and from institutional microbial collections. These new records clarify that authentic Eutypa lata and Phaeomoniella chlamydospora fungi, which are widely studied GTD pathogens, are present and probably common in New Zealand. First records of Inonotus, Diatrype, Sporocadus and Phaeoacremonium species are presented from New Zealand vineyards. The DNA sequences presented from GTD pathogens will facilitate the use of molecular detection technologies for measuring pathogen distributions in New Zealand vineyards and for biosecurity detections. [ABSTRACT FROM AUTHOR]

A single step Direct real-time quantitative reverse transcription quantitative polymerase chain reaction (DRT-qPCR) was applied and optimized for the detection of Grapevine rupestris stem-pitting associated virus (GRSPaV) in grapevine. A probe and primer set were designed from conserved genomic regions from eight GRSPaV accessions from GenBank and used with the Direct Plant Extraction Buffer (DiPEB) system in place of total nucleic acid extraction using commercial kits to identify 14 grapevine accessions and field grapevine isolates for the presence of GRSPaV. Optimal detection of GRSPaV was obtained using foliar tissue macerated first in ELISA extraction buffer that was further diluted in DiPEB buffer (1:9 v/v). Middle-aged grape leaves on young canes gave acceptably low Cq (quantification cycle) values, with no significant differences detected between bisected half leaves, refrigerated and frozen leaves, and frozen leaf macerates made in ELISA buffer. Cq values of macerates derived from cambial tissue were comparable to those of leaf tissue macerates. The DRT-qPCR was shown to be a reproducible, specific test capable of detection of as little as 4.59 pg of viral RNA. This is the first study to use this simplified method for the detection of viruses that infect grapevine. Because this system does not require the use of a commercial nucleic acid extraction kit, it provides savings in cost and time allowing higher throughput testing. [ABSTRACT FROM AUTHOR]

Lentisk dieback has been commonly observed in Tunisian forests. Nevertheless, the identity of the parasitic factors involved in this phenomenon has not yet been reported. Thus, in order to characterize the dieback-associated agents, symptomatic branches were collected from Pistacia lentiscus in the Rimel forest (Northern Tunisia). Two Botryosphaeriaceae species, Diplodia seriata and D. africana, were isolated and identified firstly based on morphological characteristics. Then, molecular identification was performed by sequencing the internal transcribed spacer region (ITS1-5.8S-ITS4), a part of the translation elongation factor 1-α (EF1-α) gene and a partial sequence of the β-tubulin (TUB) gene. The two species were morphologically and phylogenetically distinct from all Diplodia species and represent newly recorded fungal pathogens of lentisk in Tunisia. Pathogenicity tests carried out on asymptomatic detached branches confirmed the virulence of the two species. These findings may confirm D. seriata and D. africana as fungal pathogens associated with lentisk dieback in Tunisia. [ABSTRACT FROM AUTHOR]

Grapevine can be severely affected by phytoplasmas and there is no effective control strategy for management of these diseases. A technique to reduce the number of infected plants could thus arise from the stimulant of plant defence systems to induce recovery. In this order, two components (T1: propamocarb/fosetyl 530:310 g/l and T2: hymexazol) were sprayed with 4/000 concentration on the canopy of symptomatic grapevines (cv. Bidaneh Sefid) infected by phytoplasma in Qazvin and Lorestan provinces (Iran). Treatments consisted of monthly sprays in spring-2016 and 2017 (two applications) in symptomatic plants. Treated plants in 2016 showed any symptoms in next year and treatment repetition were performed in 2017, in same vineyards with different symptomatic plants. Nested PCR analysis of DNA samples extracted from recovered plants failed to detect phytoplasma infection. The results of this study show these resistance inducers could promote host defence in treated phytoplasma infected plants and could be useful for control of grapevine phytoplasma diseases in Iran. [ABSTRACT FROM AUTHOR]

Bursa tissue samples from a pullet flock in New York State that was experiencing immune suppression related disease were sent to our laboratory in 2018. A very virulent infectious bursal disease virus (vvIBDV) was identified in those samples through molecular and pathogenicity studies and designated 1/chicken/USA/1054NY/18. Phylogenetic analyses of the hypervariable VP2 nucleotide sequence region indicated that this strain belonged to genogroup 3 which comprises the vvIBDV. Partial sequence data of the VP1 gene indicated this virus also had a VP1 typical of vvIBDV. While vvIBDV have previously been identified in the United States in California and Washington State, the 1054NY vvIBDV was most closely related to isolates from Ethiopia, suggesting it is a new introduction into the U.S. The 1054NY vvIBDV was used to challenge four-week old specific-pathogen-free (SPF) layer chicks where it caused 100% morbidity and 68.7% mortality within 4 days. Upon necropsy, gross pathological findings in infected SPF birds included small yellowish coloured bursas, some with haemorrhages on the serosal and mucosal surfaces. Microscopic lesions included inflammation, severe lymphocyte necrosis, atrophy of the follicles and follicular depletion of lymphocytes. RESEARCH HIGHLIGHTS A very virulent infectious bursal disease virus (vvIBDV) was detected in a pullet flock in New York state, USA. Nucleotide sequence analysis of the vvIBDV VP2 gene indicates it is not related to previous US vvIBDV isolates and appears to be a new introduction into the US. The New York vvIBDV caused 100% morbidity and 68.7% mortality in four-week-old specific-pathogen-free chicks. [ABSTRACT FROM AUTHOR]

Lasiodiplodia theobromae is a fungal plant pathogen that has been associated with Botryosphaeria dieback of grapevine. Despite several studies on L. theobromae, until now the production of secondary metabolites by strains isolated from grapevines has not been reported. The ability of two strains of L. theobromae isolated from grapevine to produce lipophilic metabolites was studied. Although many typical compounds of lowmolecular weight were identified from the crude extracts of both strains (e.g., lasiolactols, substituted 2-dihydrofuranones, melleins, jasmonic acid, 3-indolcarboxylic acid, botryodiplodins), (2R/2S,3S,4S)-3-epi-botryodiplodin was isolated for the first time as a natural compound. Furthermore, a comparative study ofmetabolite productionwas conducted at 25 and 37 C to understand temperature effects on metabolite profiles. Some metabolites were produced only by one strain (e.g., (3S,4S)-4-acetyl-3-methyl-2-dihydrofuranone produced by LA-SOL3) and others only at a specific temperature (e.g., jasmonic acid at 25 C, botryodiplodins at 37 C). Phytotoxicity and cytotoxicity of pure compoundswere evaluated to clarify the influence of lipophilicmetabolites on the biological activities of culture filtrates of both strains. The most toxic compound for Vero and 3T3 cells was (2R/2S,3S,4S)-3-epibotryodiplodin. [ABSTRACT FROM AUTHOR]

Herein, we describe our results on the determination of the chemical profile of the essential oil (EO) of flowers from Tagetes minuta L. grown in Southern Brazil. The major component of the EO is (Z)-tagetone 1 (70.64% w/w). Thiotagetone 6, a semi-synthetic derivative, was prepared from 1 in 82% yield. Compounds 1 and 6 and the EO were evaluated for their antioxidant and antifungal activities in vitro. All the tested samples presented antioxidant effect in scavenging radical and in the lipid peroxidation assays. A good antifungal activity against Candida lipolityca, Candida parapsilosis, Trichosporon asahii and Sphaceloma ampelinum was observed. (Z)-Tagetone 1 inhibited the mycelia growth of S. ampelinum around 80% at 6 days. No acute toxicity (200 mg/kg) was observed in mice for the EO or the compounds 1 and 6. The lack of toxicity is an indicative for additional studies aiming their potential therapeutic use. [ABSTRACT FROM AUTHOR]

Vine mealybug,Planococcus ficus, is a major pest of grapevine, which is present in at least 39 countries. According to American Vineyard Foundation,P. ficusis in the top ranks among major insect-pests of grapevine. It is the ‘top priority concerns’ by grape growers and a ‘threat to the sustainability of wine industry’ demanding a ‘high priority research’. In Douro vineyards, it is considered as an occasional insect-pest; however, its importance is increasing in some localities. The present study investigates the occurrences ofP. ficus-associated fungi. Vine mealybugs were observed in two of the four surveyed farms. Out of the 183 collected mealybugs, 58 were dead of which 25 had symptoms of mycosis and 13 were parasitised. Subculturing cadavers and subsequent pathogenicity test yielded 22 entomopathogenic fungi (EPF) including yeasts. The yeastMeyerozyma (=Pichia) guilliermondii, and the EPFSarocladium kilienseandPurpureocillium lilacinumwere the most abundant, i.e. representing 18.18% (N = 4), 13.64% (N = 3) and 13.64% (N = 3) of the isolates, respectively. Considering biological affinities, fungal families Nectriaceae and Microascaceae had the most similar count-data profiles. To our knowledge, this work reports the first isolations of EPF from vine mealybug worldwide; andPseudocosmospora rogersoniiin Europe and as EPF worldwide.The mortality rate originated by mycoses onP. ficuswas significantly higher than by its parasitoids, suggesting that fungi asP. ficusbiocontrol agents are relatively more important than considered before. Overall, this report provides new insights into the development of mycoinsecticides and conservation biocontrol strategies forP. ficuspest management. [ABSTRACT FROM AUTHOR]

In 2016, grape fruits showing ripe rot symptom were found in fields of Korea. The fungus was isolated and identified as Colletotrichum viniferum based on morphological characteristics and nucleotide sequence data of the internal transcribed spacer, glyceraldehyde-3-phosphate dehydrogenase and ß-tubulin. To our knowledge, this is the first report of C. viniferum causing grape ripe rot disease of grape fruits in Korea. [ABSTRACT FROM AUTHOR]

A novel species ofBotrytisisolated from peony in Alaska, USA, and grape in Trento District, Italy, was identified based on morphology, pathogenicity, and sequence data. The grape and peony isolates share sequence homology in the glyceraldehyde-3-phosphate dehydrogenase (G3PDH), heat shock protein 60 (HSP60), DNA-dependent RNA polymerase subunit II (RPB2), and necrosis- and ethylene-inducing protein 1 and 2 (NEP1andNEP2) genes that place them in a distinct group closely related toB. aclada, a globally distributed pathogen of onions. Genetic results were corroborated with morphological and pathogenicity trials that included two isolates ofB. cinereaand two isolates ofB. paeoniaefrom peony in Alaska and one isolate ofB. aclada. The authors observed differences in colony and conidia morphology and ability to cause lesions on different host tissues that suggest that the grape and peony isolates represent a distinct species. Most notably, the grape and peony isolates did not colonize onion bulbs, whereasB. acladareadily produced lesions and prolific sporulation on onion tissue. The new speciesBotrytis euroamericanais described herein. [ABSTRACT FROM PUBLISHER]

Detection and identification of fungal pathogens associated with grapevine trunk diseases (GTDs) are often difficult and laborious. The aim of the study is to develop a simple and time-saving protocol for the identification of a broad range of fungal species causing GTDs by fragment length analysis of the internal transcribed spacer (ITS) regions 1 and 2 and the large subunit D2 hypervariable region of the ribosomal DNA (rDNA). A total of 32 fungal isolates from declining vines and six type strains, representing 19 different species was included in this study. The majority of the fungi had unique species-specific PCR products ranging from 212 to 370 bp (ITS1), 332 to 428 bp (ITS2) and 320 to 325 bp (LSU-D2), and the combination of three regions identifies all pathogenic fungi tested. The protocol proposed here provides a highly sensitive, reliable and rapid identification method for a broad range of significant grapevine fungal trunk pathogens. [ABSTRACT FROM PUBLISHER]

Grapevine red blotch-associated virus(GRBaV), which causes grapevine red blotch disease, is an emerging problem for grapevine production in the United States. However, little is known about how viruses, such as GRBaV, affect host physiology even though it is crucial to understanding host-pathogen interactions, symptom development, and potential effects on other pathogens and insect pests including potential vectors. Thus, foliar levels of amino acids, sugars, phenolics and terpenoids were examined in healthy or GRBaV-infected ‘Cabernet Franc’ (CF) or ‘Cabernet Sauvignon’ (CS) grapevines both before and after development of red blotch symptoms, in July and September of 2014, respectively. Particular amino acids were increased both before and after symptom development in both cultivars, with some of these amino acids having previously defined associations with host defences. Fructose and glucose were increased in GRBaV-infected CF at both sampling times. However, for CS only, glucose was increased in infected grapevines and only when pre-symptomatic. Phenolic levels were greater in GRBaV-infected CF and CS after symptom expression. Terpenoids were greater in infected CF in July, with no other apparent differences. Taken together, these results demonstrate the effects of GRBaV infection on host physiology, with shifts potentially associated with symptom development and changes in resistance to other organisms. [ABSTRACT FROM PUBLISHER]

A total of 41 endophytic bacterial strains were assessed for antimicrobial activity against indicator organisms in a preliminary screening. Of these, two bacterial strains that showed a strong antimicrobial activity were selected and identified asBacillus subtilis(Bs1 and Bs2). The activities of Bs1 and Bs2 strains and different bile acids were assessed againstBotrytis cinereaandPlasmopara viticolagrapevine pathogens using in vitro and in vivo methods. Bs1 and Bs2 strains strongly inhibitedBotrytis cinereagrowth in vitro. The cell-free filtrates of both strains also reducedBotrytis cinereagrowth. Chenodeoxycholic acid (CDCA) inhibitedBotrytis cinereagrowth in potato dextrose agar medium and suppressedP. viticoladevelopment in grapevine leaf discs. Epifluorescence microscopy observations revealed an important restriction ofP. viticoladevelopment at the vesicle stage. In addition, CDCA markedly reduced the ability ofP. viticolasporangia to release zoospores in vitro, confirming the direct fungicidal effect of this bile acid. [ABSTRACT FROM AUTHOR]

Fruit rots are some of the most important diseases of grape and strawberry. With recent public concern regarding pesticide residues on fruit, there is a need for alternative disease management practices that will reduce the risk to consumers. The main aim of this study was to investigate the effectiveness of the commercial product BOTRY-Zen (active ingredientUlocladium oudemansii[U3 strain]) to control strawberry and grape fruit rots. BOTRY-Zen at 6 g/L reduced significantly the percentage of rotted fruit in comparison with the untreated control. However, its effectiveness was significantly less than that of the fungicide Switch 25/37.5 WG (fludioxonil: cyprodinil) at a rate of 1 g/L (recommended by producer). There was no significant difference between the BOTRY-Zen at rate of 4 g/L and untreated plants. The results of this study showed that the commercial product BOTRY-Zen, at 6 g/L, could be a useful tool to control fruit rots of strawberry and grape in biological fruit production systems. [ABSTRACT FROM AUTHOR]

Grapevine red blotch-associated virus (GRBaV) is a recently discovered ssDNA virus that is widespread in wine grapes in California. We investigated whether GRBaV infection was present in 156 table grape accessions ofVitis viniferathat included 53 accessions exhibiting leafroll-like symptoms and 81 accessions from diverse geographic origins. Cane samples were collected during the dormant season in 2012 and analysed for GRBaV infection by PCR. A total of 73 accessions showed presence of GRBaV and these included raisin and table grape accessions with black, green and red berries. A 557 bp amplicon obtained by PCR was purified and sequenced, and the phylogenetic relationship among GRBaV isolates was examined by the maximum likelihood method. The maximum genetic variability among the isolates was only 8% and they belonged to two clades. Although it is not yet known if GRBaV is present outside of North America, 54 accessions from sources originating outside of North America tested positive for the virus. [ABSTRACT FROM PUBLISHER]

Grapevine fanleaf virus(GFLV), a member of the genusNepovirusin the family Secoviridae, is the most widely distributed grapevine virus around the world. In the present research, recombinant antibody to the GFLV coat protein (CP) was used to develop an immunocapture reverse transcription-polymerase chain reaction (IC-RT-PCR) for the detection of GFLV by the use of a pair of primers corresponding to the full length CP gene. In addition, double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) was done by the use of recombinant antibody to detect the GFLV isolates. Eventually, an expected band with around 1512 base pair (bp) in length was revealed for three isolates by IC-RT-PCR. Also, DAS-ELISA revealed that the recombinant antibody was able to detect the virus in leaf sample. These results showed that application of recombinant antibody in these detection methods can be useful for rapid detection of viruses in plant tissue because by applying IC-RT-PCR along with recombinant antibody, it is possible to overcome the limitations happened by presence of inhibitors in grapevine trees and non-specific reaction resulting from presence of native proteins in plant sap against conventionally made antibody. [ABSTRACT FROM AUTHOR]

Phaeoacremoniumspp. are known as the main Hyphomycetes associated with esca disease symptoms on grapevines worldwide. The role of other woody hosts in proximity of vineyards as a possible inoculum source for the causal agents of grapevine esca disease mainly remains unknown. The aim of this study was to investigate the occurrence ofPhaeoacremoniumspp. on pome and stone fruit with trunk diseases symptoms in northwestern parts of Iran. For this purpose, wood trees samples were collected from apple and apricot trees with trunk disease symptoms. Isolation was made using routine plant pathology methods. Based on the morphological and cultural characteristics,Phaeoacremonium aleophilumandPhaeoacremonium iranianumwere identified from apple trees andP. aleophilumwas recovered from apricot trees with trunk disease symptoms. A phylogenetic analysis based on the sequence data fromβ-tubulingene further confirmed the identity of the species asP. aleophilumandP. iranianum. The results of inoculation assay on detached shoots of apples revealed thatP. iranianumis pathogenic on apple. Our results also showed thatP. aleophilumisolates from different hosts (apple, apricot and grapevine) were pathogenic on apple and induced wood discolouration on apple stems. There was no significant difference on the length of lesions induced in relation to the origin of theP. aleophilumisolates. This study is the first report on the occurrence ofP. iranianumon apple trees with trunk disease symptoms worldwide and the first report on the occurrence ofP. aleophilumon apple and apricot in Iran. [ABSTRACT FROM PUBLISHER]

Intraguild predation of the mealybug parasitoidsAnagyrus pseudococci(Girault), andLeptomastix dactylopiiHoward (Hymenoptera: Encrytidae) byNephus kreissliFürsch & Uygun (Coleoptera: Coccinellidae) was studied. The latter is a native predator of the important pestPlanococcus ficus(Signoret) (Hemiptera: Pseudococcidae) on grapevines in Turkey. For this purpose,P. ficusof different ages parasitised byA. pseudococciorL. dactylopii, or by bothA. pseudococciandL. dactylopii, were served to fourth instars and adults ofN. kreisslias food. Experiments were conducted using two different treatments: no-choice (served unparasitised or only one stage of parasitised mealybug) and choice (served unparasitised and only one age of parasitised mealybug together), under controlled environmental conditions. Both fourth instars and adult predators were fed on two- and four-day-old mealybugs parasitised byA. pseudococcior on two-, four- and six-day-old mealybugs parasitised byL. dactylopiior by eitherA. pseudococciorL. dactylopii. The predators could not consume six-day-old mealybugs parasitised byA. pseudococci, eight-day-old mealybugs parasitised byL. dactylopii, or those parasitised by either of these parasitoids which had become mummified. While it was found that the adult predators preferred parasitised mealybugs to unparasitised, the larvae did not show a pronounced preference between parasitised and unparasitised mealybugs (except for mealybugs parasitised byA. pseudococci). [ABSTRACT FROM AUTHOR]

Seventy-five isolates of Botrytis collected from table grapes (Vitis vinifera) with gray mol symptoms in China were identified based on morpho-cultural characteristics on potato dextrose agar (20 C) and/or phylogenetic analysis using the sequences of three nuclear genes (G3PDH, HSP60, RPB2). Isolates of different species of Botrytis were compared with fenhexamid sensitivity, Bc-hch gene-RFLP haplotypin and pathogenicity to V. vinifera. The 75 isolates comprise two species, B. cinerea (63 isolates) and an undescribed Botrytis sp. (12 isolates) described here as Botrytis sinoviticola Zhang et al. sp., nov. Both B. sinoviticola (Bs) and B. cinerea (Bc) were found to have 20 C optimum for mycelial growth and 25 C for conidial germination. Sensitivity to fenhexamid was significantly greater (P < 0.05) for Bc (EC50 = 0.04 ± 0.01 μg mL-1) than for Bs (EC50 = 0.08 ± 0.02 μg mL-1). Digestion of the PCR amplicons of the Bc-hch gene with Hha I generated two haplotypes, Group I haplotype for Bs and Group II haplotype for Bc. Bs infected table grapes (leaves, berries) only through wounds, whereas Bc infected both injured and non-injured tissues of table grapes. This study suggests that Bs is a cryptic species sympatric with Bc on table grapes in China. [ABSTRACT FROM AUTHOR]

Grapevine is host to twoColomerusspecies:Colomerus vitis(Co. vitis), distributed worldwide; andColomerus oculivitis(Co. oculivitis), restricted to Egypt and Saudi Arabia. Both these eriophyid species, as well asColomerusspecimens morphologically near them, were intercepted by South African officials on table grapes and grapevine budwood imported from a number of different countries.Colomerus oculivitismay have a wider distribution than reported and/or its taxonomy may be erroneous. In addition, breeding colonies ofColomerusmites were found on imported fresh table grapes. This represents an unconsidered introduction pathway for eriophyoids on grapevine. A survey and taxonomic study on grapevine eriophyoid mites are presently underway in South Africa. Due to taxonomic uncertainties, it is our opinion thatColomerusmites from grapevine worldwide cannot be identified accurately to species. [ABSTRACT FROM AUTHOR]

Esca is a very important and destructive disease of grapevine in many grapevine producing countries. Several groups of fungi have been reported from grapevines with esca disease symptoms; however,Phaeoacremoniumspecies are the main hyphomycete fungi involved in this disease. In recent years, esca disease symptoms with consequent decline disease have frequently been observed in vineyards of north-western Iran. Nevertheless, the involvement ofPhaeoacremoniumspp. with esca disease symptoms in this region remains unknown. During 2008–2010 growing seasons, wood samples were collected from vines showing typical esca disease symptoms such as interveinal leaf chlorosis with subsequent necrosis and various types of internal wood deterioration in north-western parts of Iran. A total of 44Phaeoacremonium-like hyphomycetes were recovered from sampled materials. Fungal isolates were subjected to tentative morphological identification and were further characterised by using sequenced data from ITS-rDNA and β-tublin gene. Phylogeny inferred using sequence data from ITS-rDNA region and β-tublin gene revealed thatPhaeoacremonium aleophilumandP. mortoniaetogether withSarocladium strictum(syn.Acremonium strictum) are associated with esca disease symptoms in this region. The pathogenicity ofPhaeoacremoniumspp. andSarocladium strictumwere verified by the inoculation of cutting root and stems under greenhouse conditions. Isolates ofP. aleophilumandP. mortoniaewere the most virulent based on the length of vascular necrosis on woody stems that followed bySarocladium strictum. This is first study on the pathogenicity ofSarocladium strictumon grapevine worldwide and the first report on the occurrence ofP. mortoniaeon grapevines in north-western Iran. [ABSTRACT FROM PUBLISHER]

The appearance of the Flavescence Dorée phytoplasma and the possibility of its rapid spread by its vector, the American Grapevine Leafhopper (Scaphoideus titanusBall) (AGVL), represent a serious threat to viticulture production in Slovenia and elsewhere in Europe. Insecticide treatment represents one of major means of reducing the abundance of AGVL in wine-growing areas. In the period from 2010 to 2011, five insecticides against AGVL were tested, and the efficacy of the substances was calculated according to the number of nymphs (at 2, 7, 14 and 21 d after application), which were counted on the grapevine leaves. In both years, the highest cumulative efficacy (96–97% or 0.01 nymphs/leaf) was confirmed for thiamethoxam, whereas chlorpyrifos-methyl showed a very high cumulative efficacy (87–89% or 0.01–0.02 nymphs/leaf). In 2010, indoxacarb exhibited only a 43% (0.09 nymphs/leaf) cumulative efficacy; however, its substitute in 2011, chlorpyrifos, was more effective (73% or 0.05 nymphs/leaf). A single application of pyrethrin demonstrated only 45–61% (0.05–0.09 nymphs/leaf) efficacy. Based on the results of our research, we recommend the use of thiamethoxam and chlorpyrifos-methyl against AGVL. [ABSTRACT FROM PUBLISHER]

To determine the type of prey consumed by the predatory coccinellid, Stethorus punctum picipes (Coleoptera: Coccinellidae), we identified food remains, based on body parts or whole bodies of mites, in the guts of adults collected in two fruit orchards (apple and cherry) and one vineyard in Washington State, United States in August and September 2009. Various plant-inhabiting mites, including species in the families Stigmaeidae, Eriophyidae, Phytoseiidae, and Tetranychidae, were found in guts of S. p. picipes collected on grapevine where no tetranychids were observed. On apple, where tetranychids were abundant, gut contents contained Tetranychidae, Stigmaeidae, and Eriophyidae. On cherry, where tetranychids were abundant, only Tetranychidae were found in gut contents. These results indicate that S. p. picipes adults can feed on alternative plant-inhabiting mites, in particular, when tetranychids are scarce. [ABSTRACT FROM PUBLISHER]

During the summer season of 2003 and 2004, wilt syndromes of grapevine leaves (Cv. crimson) and vascular discolouration of roots have been observed in 2-year-old grapevine plants in the field at two sides in Gharbeia Governorate, Egypt. First, symptoms of wilt began on bottom leaves borderline as chlorosis and then these turned to necrotic spots and the leaves died. Wilt symptoms were spread to apical associated with vascular discolouration of roots and stem basal. Routine isolations of discoloured root tissue from diseased plant yielded eight isolates of Fusarium oxysporum Schlechtend only where no other fungi were developed. Microscopic examination revealed the presence of three shapes of microconidia, first is avoid shape non-septate measuring 2.5-3.0 μm × 6-10 μm, second is cylindrical with one septa measuring 2.6 μm × 17.0 μm and third shape also cylindrical with two septate measuring 3.0 μm × 20.0 μm. Macroconidia was rarely with three septate measuring 3.5- 4.0 μm × 35.0-38.0 μm, and chlamydospores were found singly or in pairs or chains. F. oxysporum isolates attacked grapevine plants (Cv. crimson) causing vascular wilt (66.7%) and root-rot syndrome (33.3%). In vitro isolates of F. oxysporum causing wilt of grapevine (Cv. crimson) varied for producing lytic enzymes, i.e. polygalacturonase (PG) and cellulase. The reactions of several grapevines (Cvs.) with a virulent isolate of F. oxysporum indicated the presence of two different symptoms, i.e. vascular wilt only on grapevine plants (Cv. crimson) and root-rot on the other grapevine (Cvs.), i.e. superior, Thompson, King robi and flame seedless. All F. oxysporum isolates caused vascular wilt of grapevine Cv. crimson, successfully reisolated from symptomatic vascular infected tissue and complete identification on the basis of colony, conidia morphology and host range at formae speciales level as F. oxysporum f. sp. herbemontis (Tochetto) Gordan. This is the first report of Fusarium wilt on grapevine in Egypt. [ABSTRACT FROM AUTHOR]

Saline irrigation water having high sodium (Na+) content leads to the development of black leaf disorder in the vines resulting in reduced productivity and death of permanent vine parts. The response of the vines raised on different rootstocks differs under such conditions. Investigation was carried out to study the susceptibility of grafted and own-rooted Thompson Seedless (Vitis vinifera L.) vines to black leaf disorder. Grapevines grafted on four different rootstocks viz. Dog Ridge (Vitis champini), Salt Creek (Vitis champini), B2-56 (Vitis berlandieri x Vitis rupestris) and 1613C [Vitis longii x (Vitis labrusca x Vitis riparia) x Vitis vinifera] were studied. The variations in nutrient content of various vine parts under saline irrigation in relation to leaf blackening and necrosis symptoms were also studied. Thompson Seedless vines grafted on Dog Ridge, Salt Creek and own rooted vines started developing leaf blackening and necrosis symptoms during the ripening stage. Vines exhibiting these symptoms contained significantly lower potassium (K+) and higher Na+ content in the leaf blades as compared to healthy vines. Vines grafted on Salt Creek showed most severe leaf blackening and necrosis symptoms and had the lowest K+ content in blades and petioles. Amongst the rootstocks, vines raised on B2-56 had the lowest Na+ concentration in leaf blades whereas those on Dog Ridge and Salt Creek accumulated Na+ in leaf blades to a toxic level. Significantly higher K+ content was found in vines raised on B2-56 and 1613C rootstocks in all the vine parts compared to other stock-scion combinations. Vines grafted on B2-56 and 1613C could maintain higher K+: Na+ ratio and tolerated saline irrigation better than other stock-scion combinations. All the rootstocks reduced chloride concentration significantly in the vine parts (petioles, blade and canes) compared to own rooted vines. Vines raised on their own roots and on B2-56 rootstock had significantly higher phosphorus (P) concentration in petiole, blade and canes compared to vines grafted on Dog Ridge and Salt Creek. Total biomass (petiole + blade + cane on dry weight basis) and yield was the highest in B2-56 rootstock and least in 1613C. [ABSTRACT FROM AUTHOR]

The female of a new species, Typhlodromus (Anthoseius) atoosae n. sp. collected from a grapevine in Cataluna, Spain is described and illustrated. The species of Amblyseius bryophilus Karg, A. filixis Karg, Aristadromips masseei (Nesbitt), T. (A.) kerkirae Swirski & Ragusa, Typhlodromina conspicua (Garman) represent new distribution records for France and Typhloseiulus simplex (Chant) is a new distribution record for Spain. The measurements and illustrations of these new records are given. Re-description of A. meridionalis Berlese and new morphological data on T. (A.) rhenanoides Athias-Henriot collected in France are also given. [ABSTRACT FROM AUTHOR]

The spatial distribution of the leafhopper Scaphoideus titanus Ball, the vector of the pathogen Flavescence dorée of grapevine, was studied in the Asti Province (Piedmont) Italy. Field sampling of adults was carried out using yellow sticky traps both in vineyards subjected to different pest management regimes, and in woods containing American grapevines. The spatial correlation of S. titanus captures was studied using geostatistical analyses. An artificial neural network (ANN) was designed to operate as a spatial predictor driven by external factors (elevation, slope, height above channel, agricultural communities, perimeter-to-area ratio, potential solar radiation, and pest management) for estimating the population density of the leafhopper. The captures were spatially related up to 210 m: the variogram fitting was significant, but resulted in low R2 values. The ANN achieved a significant generalization of the infestation levels of S. titanus, permitting prediction maps based upon simulated pest management scenarios to be obtained. The most important factors affecting S. titanus population density were pest management, and secondarily agricultural communities. [ABSTRACT FROM AUTHOR]

In October 2006, much of the wine-growing area in Tasmania was affected by a series of some of the worst frost events in more than 30 years. Widespread damage left vineyards with blackened shoots and the prospect of a considerably smaller crop, with later maturing bunches from secondary buds contributing to poorer quality wine. In a commercial, spur-pruned Pinot Noir planting, treatments intended to encourage and manipulate secondary bud-burst are imposed and effects on yield recorded. Treatments are imposed 10 days after the frost and include: (i) an untreated control (control) with all damaged tissue left in place; (ii) frost-damaged tissue removed (light pruning); (iii) frost-damaged tissue removed and original spur trimmed back to one bud (medium pruning); and (iv) original (damaged) shoot removed back to compound bud on the spur (heavy pruning). Pruning treatment responses for season 2006-07 show that heavy pruning reduces the current crop with no useful gain in uniformity of ripening. The medium and heavy pruning treatments also reduce pruning weights at the end of the season and all post-frost pruning treatments result in a smaller inflorescence primordia size in dormant buds dissected at the beginning of commercial pruning. In the 2007-08 vintage, the untreated control and the medium pruning treatment have significantly lower bunch numbers than the other treatments. There is also a significant effect of terrain elevation on total yield and the number of bunches in the frost year, with increasing damage lower in the inversion. This gradation in damage does not have carry-over effects into the second season. The results indicate that none of the pruning treatments tested have clear benefits for current or subsequent season production, and that a prescriptive approach to pruning should be avoided when the level of frost damage is inconsistent across vines. [ABSTRACT FROM AUTHOR]

Augmentation of soil with different biological treatments i.e., Trichoderma harzianum cultured on sugar cane bagasse, Trichoderma harzianum (spore suspension 5 × 106 cfu/ml) and plant guard (biocide), successfully controlled Fusarium solani, F. oxysporium and Macrophomina phaseolina, the main pathogens of root rot disease on grapevines in Nobaria province. Complete reduction of these pathogens was recorded at 4 ml/l of plant Guard. Meanwhile, T. harzianum caused a reduction of 80.0, 84.4 and 88.9% of linear growth of the same pathogens respectively. In greenhouse trials, artificially infested soil treated with bio-enhancing bagasse at rate of 10% (w/w) of soil, plant guard 4 g/l and T. harzianum 100 ml/l treatments showed a large effect in decreasing percentages of infection and severity of root rot disease on grapevine seedlings. These treatments caused a reduction in root rot infection caused by M. phaseolina, F. oxysporum and F. solani reach 100, 100, 80% and 80, 60, 60% and 60, 40, 40%, respectively, with two soil applications. Also, the percentage reduction in disease severity reach 100, 100 and 88.2%; 69.2, 57.1 and 52.9%; 46.2, 42.8 and 41.2% respectively. Meanwhile, one soil application with the same treatments caused a moderate effect in decreasing both disease infection and severity. Two soil applications with bio-enhancing bagasse 10% and plant Guard 4 ml/l treatments caused significantly reduced numbers of infested vines as well as percentage of disease severity of these vines after 30, 60 and 120 days from application. Moreover, these treatments cause an increasing population density of Trichoderma spp., wherever it decreases in the rhizosphere soil of untreated vines (control). The large increase in yield/vine was recorded on vines treated with bio-enhancing bagasse 10% (51.2% increase over control) and Plant Guard 4 ml/l (48.8% increase over control) in two applications. Through these results it can be suggested that manipulating soil by biocontrol agent formulation on agricultural wastes or as biocides such as plant guard may be safely used commercially as a substitute for traditional fungicidal treatments for controlling soil borne plant pathogens. [ABSTRACT FROM AUTHOR]

The article presents information on a study conducted on the prevention of powdery mildew, a grape disease caused by Erysiphe necator in Quebec. It is stated that the production of secondary inoculum is a major factor in the development of powdery mildew. To manage the disease, a fungicide spray program was developed, in which fungicides were sprayed on the plant at different intervals and with different concentrations.

Tempranillo grapes were immersed in solutions of pyrimethanil, metalaxyl, dichlofluanid and penconazol fungicides at different concentrations for several different times. Determinations of the fungicide residues was carried out by GC-NPD, with an additional confirmation by GC-MS. The percentage absorption was determined as well as the distribution between surface, skin and pulp of the grapes. The percentage absorption ranged from 7.2 to 85.5%. These values depended on the time the grapes were in contact with the fungicide solutions. Residues were mainly found in skins, with percentages in skins ranging from 66.3 to 90.3% of total residues. In pulp, these values ranged from 3.5 to 31.0%. The overall methodology was applied to the determination of pyrimethanil in Tempranillo grapes treated with the recommended doses, respecting the safety period. Pyrimethanil residues found in treated grapes were higher in the skin. In grapes collected within the safety period (21 days), the levels found for fungicide residues were below maximum residues levels. [ABSTRACT FROM AUTHOR]

Grapevine downy mildew is the most devastating disease throughout the world causing huge monetary losses. Twenty medicinal plant extracts and six phylloplane microfloras were evaluated for their efficacy against sporangial germination of grapevine downy mildew pathogen Plasmopara viticola in vitro. The results revealed that the Neem Seed Kernel Extract (NSKE) at 5% significantly inhibited the sporangial germination (75.36%) of P. viticola. Among the phylloplane microflora Pseudomonas fluorescens was highly effective in reducing the sporangial germination (64.26%). Post inoculation spraying of NSKE (5%) and P. fluorescens (0.2%) effectively inhibited the disease development in the greenhouse. Three sprays with NSKE (5%) and phylloplane P. fluorescens (0.2%): first spray after initial appearance of disease and the second and third at 10 day intervals were found to be promising in reducing disease incidence in the field. [ABSTRACT FROM AUTHOR]

Grapevine anthracnose is one of the most devastating diseases in vineyards worldwide. Wanis a botanical formulation containing monoterpene derivative was evaluated in vitro for its efficacy to inhibit the growth of Gleosporium ampelophagum causing anthracnose disease on grapevine. Wanis at 0.5% completely inhibited the mycelial growth of G. ampelophagum on solid and liquid media. The diameter of the inhibition zone formed by 0.5% wanis was the highest on solid media in paper disc assay. Conidial germination of G. empelophagum was also totally inhibited by the wanis (0.5%). Three sprays with wanis (0.5%): the first spray immediately after the appearance of disease and the second and third at 15 day intervals on field grown grapevine plants effectively reduced the anthracnose disease. [ABSTRACT FROM AUTHOR]

Grapevines (Vitisspp.) are very susceptible to virus diseases. Virus infection reduces fruit yield and quality. The objective of this work was to determine the usefulness of thermotherapy (37.2°C) and in vitromeristem culture to obtain virus-free grapevine plants cv. 'Chancellor'. Grapevine leafroll-associated virus 1,3(GLRaV-1, 3) infected grapevines were multiplied in vitrofrom two infected mother-plants in half strength Murashige and Skoog medium (1/2MS) supplemented with 0.5 mg/L of BA and the in vitroplants were initially tested by ELISA to confirm their virus status; subsequently, 96 infected in vitroplants were propagated on 1/2MS medium with BA and subjected to 0, 7, 10, 12, 14, 16, 18, 20 or 22 days of exposure at 37.2°C. Afterward, the apical meristems from the plants surviving the thermotherapy treatment were excised and transferred to fresh 1/2MS medium with 0.5 mg/L of BA and grown in a culture room until they developed into entire plants. Control plants and all the plants that survived thermotherapy were assessed for their virus status using both ELISA and RT-PCR. After 20 days of exposure at 37.2°C, 100% of the plants submitted to thermotherapy were found to be virus-free by RT-PCR and ELISA tests. Plants derived from meristems with two or three primordial leaves remained virus infected. However, when meristem culture was combined with thermotherapy (12 or more days of heat treatment), all the meristem-derived plants were virus-free. [ABSTRACT FROM AUTHOR]

Sour rot on White Riesling grapes increased oBrix, glucose to fructose ratio, titratable acidity, tartaric acid, glycerol and gluconic acid while reducing berry weight. Sour rot did not influence pH, acetic acid, ethanol or laccase activity.Two classes of grape aroma components, potentially volatile terpenes (PVT) and free volatile terpenes (FVT),were not influenced by sour rot. However, quantitative differences in selected free aroma compounds between ''clean'' and rot-degradated fruit were observed. Rot reduced free geraniol, nerol, and linalool concentrations, while increasing trans-furan linalool oxide, benzyl alcohol, 2-phenylethanol, 2-methyl-1- propanol, and 3-methyl-1-butanol. [ABSTRACT FROM PUBLISHER]

Abstract. The bat, Cynopterus sphinx Vahl (Megachiroptera: Pteropodidae), seriously damages grapes in India. Foraging ecology and non-destructive control of the bat, C. sphinx , was studied at the Indian Institute of Horticultural Research, Bangalore. Bat damage was found to be positively correlated with fruitmaturity and itbegins atleasta fortnight prior to harvest, when fruits startmaturing. Peak damage was recorded 8 days prior to harvest. Damage was significantly higher where open space, adjacent to the vineyard, was available and lower on the vines closest to a mango orchard, 10 m away from the vineyard. It was inferred that growing trees around the vineyard may deter bat foraging. Erecting around-bower nylon netting (5 5 cm, mesh) from ground level to bower height, did not prevent bat damage. In addition to erecting around-bower netting, erecting within-bower netting (in a zigzag manner) to obstruct flight within the orchard, also did not appreciably reduce the bat damage. This study also showed thatvines closerto open space had more bat damage than vines which were adjacent to physical barriers like trees and mango orchards. The best management strategy was found to involve erecting the nylon netting around-bower plus covering canopy gaps on the bower with twigs and briers; this gave effective control of the bat in four seasons of trial. This treatment is both nondestructive and cheap. The bat's usefulrole as a pollinator offoresttrees is thus not compromised. [ABSTRACT FROM AUTHOR]

Abstract. The analysis of disease incidence data when diseased plants are aggregated in clusters is discussed. The logistic-normalbinomial distribution provides a basis both for analysing experiments according to their factor structure and for describing the observed frequency distribution of affected plants per sampling unit. These analyses are illustrated with data from disease assessments of Eutypa dieback of grapevine in Californian vineyards. A comparison of the results of this study with those of a previous one suggests that clustering of Eutypa dieback may occur on different scales, dependent on the presence ofperithecia ofthe causal organism, Eutypa lata , in a vineyard. [ABSTRACT FROM AUTHOR]

Discusses the abstract of the article "Validation of impaction-type spore sampler as a tool to estimate inoculum of Uncinula necator," by R. Bacon, B. Talbot and O. Carisse, submitted to the 2003 Canadian Phytopathological Society Annual Meeting in Montreal, Quebec.