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Pear is the third most widely grown fruit species in China, a region accounts for over 60% of the world’s pear cultivation area and production. Pear scab (Venturia nashicola and Venturia pirina) is...

Scab (caused by Venturia carpophila) is a major disease affecting peach in the eastern United States. The aims of the study were to characterize the mating-type loci in V. carpophila, determine whether they are in equilibrium, and assess the population genetic diversity and structure of the pathogen. The mating-type gene MAT1-1-1 was identified in isolate JP3-5 in an available genome sequence, and the MAT1-2-1 gene was PCR amplified from isolate PS1-1, thus indicating a heterothallic structure. Mating-type loci structures were consistent with those of other Venturia spp. (V. effusa and V. inaequalis): the mating-type gene is positioned between APN2 encoding a DNA lyase and a gene encoding a Pleckstrin homology domain. Primers designed to each of the mating-type genes and a reference gene TUB2 were used as a multiplex PCR to screen a population (n = 81) of V. carpophila from various locations in the eastern United States. Mating types in five of the nine populations studied were in equilibrium. Among the 81 isolates, there were 69 multilocus genotypes. A population genetic analysis of the populations with >10 individuals (four populations) showed them to be genetically diverse. Linkage disequilibrium was found in five of nine populations with ≥4 isolates. A discriminant analysis of principal components indicated three genetic clusters, although extensive admixture was observed. Mating-type identification in V. carpophila provides a basis for understanding reproductive methods of the pathogen and can be a basis for further studies of the genetics of the peach scab pathogen.

Genus Venturia Schrottky, 1902 HfflŪÑIJşḏnjffi¨ Venturia Schrottky, 1902: 102. Type species: Venturia argentina Devorgilla Cameron, 1907: 51. Type species: Devorgilla dilatata Balcarcia Brèthes, 1922: 133. Type species: Balcarcia bergi Notamorphota Blanchard, 1946: 292. Type species: Notamorphota timocraticae Slenda Gauld, 1984: 282. Type species: Slenda ocypeta Diagnosis. Generally body slender. Mandible without a ventral flange. Pronotum moderately long in lateral view; mesopleuron with polished speculum. Propodeum long and almost completely areolated except that areola and petiolar areas confluent; apex of propodeum reaching at least to middle of the hind coxa. Fore wing with or without areolet. Key to species of the genus Venturia in South Korea 1. Body 11.5-13.0 mm; fore wing 7.5-8.0 mm long. Antenna with 40 flagellomeres. Fore wing with areolet and long stalk. Hind tibia entirely dark brown to black. Ovipositor strongly long, twice longer than 1 st tergite. Apical margins of metasomal tergites truncated in lateral view ······························ Venturia longipropodeum - Body 6.5-8.5 mm; fore wing 3.8-4.5 mm long. Antenna with 27-31 flagellomeres. Fore wing without areolet. Hind tibia brown, darkened basally and apically. Ovipositor almost as long as 1 st tergite. Metasomal tergites shiny, apical margins of tergites round in lateral view and concave in dorsal view············································ ······················ Venturia tenuiabdominalis Choi sp. nov., Published as part of Choi, Jin-Kyung, 2022, Description of a new species of the genus Venturia Schrottky (Hymenoptera: Ichneumonidae: Campopleginae) from South Korea, pp. 128-131 in Journal of Species Research 11 (2) on pages 128-129, DOI: 10.12651/JSR.2022.11.2.128, http://zenodo.org/record/8120099, {"references":["Schrottky, C. 1902. Neue argentinische Hymenoptera. Anales del Museo Nacional de Buenos Aires 8: 91 - 117.","Cameron, P. 1907. Hymenoptera of the Dutch expedition to New Guinea in 1904 an 1905. Part II: Parasitic Hymenoptera. Tijdschrift voor Entomologie 50: 27 - 57.","Brethes, J. 1922. Himenopteros y Dipteros de varias procedencias. Anales de la Sociedad Cientifica Argentina 93: 119 - 146.","Blanchard, E. E. 1946. Seis nuevos Campopleginos Argentinos (Hym. Ichneumonidae). Acta Zoologica Lilloana 3: 289 - 305.","Gauld, I. D. 1984. An introduction to the Ichneumonidae of Australia. British Museum (Natural History) Publication. No. 895. 413 pp."]}

Venturia tenuiabdominalis Choi sp. nov. (Fig. 1) ḦĿHfflŪÑIJşḏnjffi (ṵḋ) https://zoobank.org/urn:lsid:zoobank.org:act:652F061E-4F9B-4BE5-AD6A-024FD1FC8804 Description (female holotype). Female. Fore wing 3.9 mm (3.8-4.5 mm), body 7.2 mm (6.5-8.5 mm), ovipositor 2.0 mm (1.6-2.0 mm) long. Color. Head black; mandible, palpi, and antenna brown; tegula dark brown; fore and mid legs brown; hind coxa brown, darkened basally; hind tibia brown, darkened basally and apically; petiole and 2 nd tergite black; the rest parts of tergites brown, darkened dorsally; ovipositor reddish brown; ovipositor sheath black. Head: Face convex, densely granulated, distance between margin of antennal socket and clypeal margin 1.08 times as long as distance between of minimum length of inner orbits. Clypeus not separated from face. Malar space 0.5 times as long as basal width of mandible. Lower tooth of mandible as long as upper one. Frons and temple densely granulated. Vertex slightly granulated. Occipital carina weak but complete, concave in dorsal view. Temple 0.7 times as wide as transversal diameter of eye in lateral view. Distance between lateral ocellus and eye 1.3 times as long as ocellus maximum diameter. Antenna with 31 flagellomeres (27-31 flagellomeres). First flagellomere 4.4-4.5 times as long as wide, basal flagellomeres elongated and apical flagellomeres square. Mesosoma: Elongated. Pronotum slightly granulated with numerous striae centrally; epomia present. Mesoscutum roughly and densely granulated; without notaulus. Mesopleuron regularly punctate; speculum weak convex and glabrous. In front of speculum with transversal striae and mesopleural pit weak. Epicnemial carina complete and sternaulus weak. Mesoscutellum convex, without lateral carina. Metapleuron densely granulated. Propodeum elongated, well developed median longitudinal carinae and with transversal wrinkles, surface granulated. Propodeum reaching at the apical hind coxa. Propodeal spiracle very small and round, not reaching pleural carina. Submetapleural carina present. Legs slender and thin. Trochanter longer than trochantellus. Hind tarsi ratio is 16: 7: 5: 3: 4. Tarsal claw simple. Fore wing without areolet, vein 1 st intercubitus longer than cubitus. Nervulus vein distad to basal vein. Hind wing with four distal hamuli. Nervellus intercepted lower 0.3; discoidella investigial. Metasoma: Elongated. Petiole smooth, lateral carina present, lateral pit and glymma absent. Basal area of 2 nd sternite with transversal wrinkles. Tergites smooth and glabrous. Margins of tergites 3-7 round in lateral view and concave in dorsal view. Ovipositor thick and upcurved with notch of upper valve, longer than hind tibia. Ovipositor sheath thin. Male. Unknown. Material examined. [South Korea] (TD: DNUE_IIEI): Holotype: $, CB, Danyang-gun, Youngchun-myeon, Namcheon-ri, Mt. Sobaeksan National Park, 6-28. vii.2006, J.W. Lee. Paratypes: 4$$, CB, Danyang-gun, Youngchun-myeon, Namcheon-ri, Mt. Sobaeksan National Park, 6-28.vii.2006, J.W. Lee; 1$, ditto, 28.vii-13.viii.2006, J.W. Lee; 2$$, CB, Danyang-gun, Danyang-eup, Cheongdong-ri, 59 site, 25.vii-6. viii.2009, S.H. Oh; 2$$, ditto, 6-18.viii.2009, S.H. Oh; 1 $, CN, Gyeryong-si, Sindoan-myeon, Buam-ri, Mt. Gyeryongsan National Park, Gapsa, 17.v-26.viii.2012, J.W. Lee; 1 $, CN, Gyeryong-si, Sindoan-myeon, Buam-ri, Mt. Gyeryongsan National Park, Sutonggol, 17.v-29. viii.2012, J.W. Lee; 2$$, GG, Gapyeong-gun, Cheongpyeong-myeon, Goseong-ri, Mt. Homyeongsan (Malaise trap), 16-30.vii.2009, J.O. Lim; 1 $, GN, Hamyang-gun, Macheon-myeon, Meokjeon-ri, Baekmu-dong, Mt. Jirisan National Park, 14.vii-11.x.2011, J.C. Jeong. Host. Unknown. Distribution. South Korea. Etymology. Name originates from the Latin “tenuis”, tenuiabdominalis meaning “slender abdominalis”. Remarks. It is similar to Venturia ocypeta (Gauld, 1984), but divers by ovipositor longer than hind tibia (ovipositor shorter than hind tibia in V. ocypeta); hind tibia brown and darkened apically and basally (hind tibia entirely brown to dark brown in V. ocypeta); nervellus intercepted lower 0.3 (nervellus not intercepted but curved in V. ocypeta); antennal flagellomeres and body length longer than V. ocypeta (27-31 flagellomeres in V. tenuiabdominalis sp. nov. but 21-23 flagellomeres in V. ocypeta)., Published as part of Choi, Jin-Kyung, 2022, Description of a new species of the genus Venturia Schrottky (Hymenoptera: Ichneumonidae: Campopleginae) from South Korea, pp. 128-131 in Journal of Species Research 11 (2) on pages 129-130, DOI: 10.12651/JSR.2022.11.2.128, http://zenodo.org/record/8120099, {"references":["Gauld, I. D. 1984. An introduction to the Ichneumonidae of Australia. British Museum (Natural History) Publication. No. 895. 413 pp."]}

Fungal spores and hyphal fragments have been associated with out-door allergens and constitute human, animal and plant pathogens with long history of epidemiology. Airborne fungal spores of Akoko environment during the months of October 2016 to September 2017 were trapped and analyzed palynologicaly to determine the genera with allergic and pathogenic implications. Very high concentrations of these aerospora were documented. Out of 35 fungal spore type identified, the most commonly documented genera were species ofNigrospora,Endophragmiella,Ustilago,Botryodiplodia,Curvularia,Pithomyces,CorynesporaandVenturiaamong others. The availability of these airborne fungal spore types is not only a reflection of their degree of abundance in the atmosphere, but an indication of the availability of host plants and other spore sources in the region. Statistical analysis shows that there was significant difference in the mean monthly fungal spore recorded. Multiple comparisons (using DMRT) showed that the mean fungal spores recorded in the month of October was significantly different (P

In this study conducted between March 2010 and August 2011 to determine the Ichneumonidae (Hymenoptera) fauna of Denizli Honaz Mountain National Park, 31 species belonging to 12 subfamilies from six stations were identified with atrap and malaise trap. These three species identified in the study are new records for the fauna of Turkey. These are Diadegma insectator (Schrank, 1781), Diadegma aculeatum (Bridgman, 1889) and Venturia atricolor (Gyorfi, 1946). In this study conducted between March 2010 and August 2011 to determine the Ichneumonidae (Hymenoptera) fauna of Denizli Honaz Mountain National Park, 31 species belonging to 12 subfamilies from six stations were identified with atrap and malaise trap. These three species identified in the study are new records for the fauna of Turkey. These are Diadegma insectator (Schrank, 1781), Diadegma aculeatum (Bridgman, 1889) and Venturia atricolor (Gyorfi, 1946).

Members of Venturiales (Dothideomycetes) are widely distributed, and comprise saprobes, as well as plant, human and animal pathogens. In spite of their economic importance, the general lack of cultures and DNA data has resulted in taxa being poorly resolved. In the present study five loci, ITS, LSU rDNA, tef1, tub2 and rpb2 are used for analysing 115 venturialean taxa representing 30 genera in three families in the current classification of Venturiales. Based on the multigene phylogenetic analysis, morphological and ecological characteristics, one new family, Cylindrosympodiaceae, and eight new genera are described, namely Bellamyces, Fagicola, Fraxinicola, Fuscohilum, Neofusicladium, Parafusicladium, Pinaceicola and Sterila. In addition, 12 species are described as new to science, and 41 new combinations are proposed. The taxonomic status of 153 species have been re-evaluated with 20 species excluded from Venturiales. Based on this revision of Venturiales, morphological characteristics such as conidial arrangement (solitary or in chains) or conidiogenesis (blastic-solitary, sympodial or annellidic), proved to be significant at generic level. Venturia as currently defined represents a generic complex. Furthermore, plant pathogens appear more terminal in phylogenetic analyses within Venturiaceae and Sympoventuriaceae, suggesting that the ancestral state of Venturiales is most likely saprobic.

Olive leaf spot (OLS), caused by Venturia oleaginea, is one of the most common and serious diseases of olive trees in the Mediterranean region. Understanding the pathogen life cycle is important for the development of effective control strategies. Current knowledge is incomplete owing to a lack of effective detection methods. It is extremely difficult to culture V. oleaginea in vitro, so primers were designed to amplify and sequence the internal transcribed spacer ITS1-5.8S-ITS2 region of the fungus directly from infected olive leaves. Sanger sequencing indicated a unique ITS region present in the European strains screened, confirming the appropriateness of the target region for developing a quantitative PCR (qPCR) assay. Furthermore, high-throughput sequencing of the same region excluded the presence of other Venturia species in the olive phyllosphere. The qPCR assay proved very specific and sensitive, enabling the detection of approximately 26 copies of target DNA. The analysis of symptomless leaves during early stages of the epidemic from the end of winter through spring revealed a similar quantity of pathogen DNA regardless of the leaf growth stage. In contrast, the pathogen titer changed significantly during the season. Data indicated that leaf infections start earlier than expected over the season and very young leaves are as susceptible as adult leaves. These findings have important practical implications and suggest the need for improved scheduling of fungicide treatments. The qPCR assay represents a valuable tool providing quantitative results and enables detection of V. oleaginea in all olive organs, including those in which OLS cannot be studied using previously available methods.

Pecan scab, caused by Venturia effusa, is a devastating disease of pecan (Carya illinoinensis), which results in economic losses on susceptible cultivars throughout the southeastern United States. To enhance our understanding of pathogenicity in V. effusa, we have generated a complete telomere-to-telomere reference genome of V. effusa isolate FRT5LL7-Albino. By combining Illumina MiSeq and Oxford Nanopore MinION data, we assembled a 45.2-Mb genome represented by 20 chromosomes and containing 10,820 putative genes, of which 7,619 have at least one functional annotation. The likely causative mutation of the albino phenotype was identified as a single base insertion and a resulting frameshift in the gene encoding the polyketide synthase ALM1. This genome represents the first full chromosome-level assembly of any Venturia sp.

Studies conducted in perennial plantations of fruit crops of the Research Institute “Zhiguliy Gardens” in 2015-2018 showed that the main disease in the apple orchard is the scab Venturia inaqualis (Cooke) G. Winter. The variety most susceptible to this pathogen is the apple variety Spartak. Weather conditions in 2015, 2016 and 2017 favored the development of scab epiphytotics. Monitoring of the scab development dynamics taking into account the weather conditions made it possible to change the plant protection scheme in a timely manner and achieve a positive dynamics of reducing the development of scab on leaves and fruits in 2018 and reduce the stock of the pathogen for 2019.

Four new species ofVenturiaSchrottky, 1902 (Hymenoptera, Ichneumonidae, Campopleginae) from Oriental China and Nepal are described (V. contiguussp. nov.andV. yunnanensissp. nov.from China;V. liuaesp. nov.andV. levocarinatasp. nov.from Nepal). In addition, two species are reported from China (V. serpentinaMaheshwary, 1977 andV. inclyta(Morley, 1923)) for the first time and all listed species are illustrated. A key to all species from China and Nepal is provided.

Boreal forests receive nitrogen-(N)-enrichment via atmospheric deposition and industrial fertilization. While it is known that N-enrichment can intensify interactions with natural antagonists, it remains poorly understood how genetic variability in plant defense chemistry can affect biotic interactions and height growth in N-enriched environments. We grew replicates of five low- and high-tannin Populus tremula genotypes, respectively, under three N-treatments (ambient, 15, and 150 kg N ha−1 yr−1). We assessed shoot blight occurrence (i.e. symptoms caused by Venturia fungi) during four growing seasons, and tree height growth during the same period. Damage by Venturia spp. increased with N-addition during all years, likely due to enhanced foliar quality. Low–tannin plants showed higher incidences of Venturia infection than high-tannin plants, regardless of the N-input-level. Height responded to an N-by-tannin-group interaction, which occurred because high-tannin plants grew taller than low-tannin plants at the high N-treatment, but not under the other N-levels. This pattern indicates that innate resource investment into tannin production yields a positive effect on growth under N-enriched conditions. Given that N-deposition is increasing globally, our research suggests that further studies are needed to investigate how N-enrichment interacts with plant defense traits globally. Moreover, our research suggests that N-deposition may provide an advantage for well-defended, high-tannin plants; and further, that genetic diversity in plant defense may be a key mechanism by which plant populations respond to this change.

Apple cv. 'Huangtaiping' (Malus pumila Mill.) is grown widely in northern China for the production of jellies, preserves, and cider. In 2018, atypical scab symptoms were observed on fruits of Huangtaiping in Heilongjiang Province of China. The disease incidence was estimated at approximately 0.4%. Symptoms were scab-like black spots (3 to 5 mm diam.) distinct from scab caused by Venturia inaequalis. Conidia were generally produced on lesions and using a modified microscope (Goh 1999), a single spore was picked up from each sample on water agar plate with a glass needle and then transferred to PDA amended with lactic acid (0.50 ml/L) and sulfate streptomycin (0.20 g/L). Fifteen isolates were obtained and incubated at 21°C for 6 weeks in darkness on PDA. The colonies on PDA were gray-black with circular morphology and floccose texture, which were similar with the characteristics of V. asperata described previously (Turan et al. 2019). The conidia were cylindrical to fusiform, 0 to 1 septate, yellowish and 19.7 (13.5 to 25.8) × 5.7 (3.6 to 6.9) μm (n = 10) in size, which were larger than previously described ones (Turan et al. 2019). DNA of three randomly selected isolates were extracted by a modified SDS method (Ping et al. 2004). The internal transcribed spacer (ITS) region of rDNA of the three selected isolates was amplified with the primers ITS4/ITS5 (White et al. 1990), sequenced and deposited in GenBank (MN958665, MN95866 and MN958667). BLAST analysis showed that the amplified sequences were identical and had 99.3% sequence identity with V. asperata (AF333447, MT459450 and MT459451), 95.4% sequence identity with V. cerasi (MK810963 and MK810964) and 94.3% sequence identity with V. carpophila (MN958609, MN958610 and MN958611). In addition, the complete large subunit ribosomal RNA gene (LSU) was amplified with the primers LROR/LR5 (Vilgalys and Hester 1990), sequenced and deposited in GenBank (MT845787, MT845788 and MT845789). BLAST analysis showed that the amplified sequences were identical and had 99.7% sequence identity with V. asperata (EF114711), 99.2% identity with V. carpophila (MT772296, MT845732 and MT845733 ) and 98% identity with V. cerasi (MK810848 and MK810849). Phylogenetic analysis based on concatenated ITS and LSU sequences showed that the tested isolates grouped with V. asperata strain 2349 in the same clade and the closest species with V. asperata was V. carpophila, followed by V. cerasi. In July 2019, pathogenicity of the isolate VAHLJ3-1-1 was evaluated on Huangtaiping. A conidia suspension with a concentration of 5×105/ml was sprayed evenly on the surface of six fruits. In order to maintain high humidity, inoculated fruits were wrapped with a plastic bag (a cotton ball with water was placed in the plastic bag) to maintain wetness for 3 days. Six fruits sprayed with water were used as a control. Four weeks after inoculation, similar symptom of atypical scab was observed on fruits of Huangtaiping, and V. asperata was isolated again from six inoculated fruits with reisolation frequency of 100% by the single spore isolation, while no symptom was observed on the control fruits. Based on the morphological and molecular identifications, the causal agent of atypical scab on Huangtaiping was identified as V. asperata. Apple scab is usually caused by V. inaequalis (Shen et al. 2020). However, apple scab has also been caused by V. asperata in Italy and France (Caffier et al. 2012; Turan et al. 2019). To the best of our knowledge, this is the first report of V. asperata associated with apple scab-like lesions in China. This information augments our knowledge of the spectrum of Venturia species associated with disease on apple fruit and will be a valuable foundation underpinning management strategies for this cultivar.

The aim of the present study was to verify the possibility of using biostimulants alone or in mixture with fungicides for the management of Apple Scab (AS). For this purpose, 'Gala' apple trees were sprayed from September until November of the years 2014 to 2018, among one and two days before a rainy season with different classes of biostimulants (amino acids, phosphites, foliar fertilizers based on plant extract, algae and minerals). Some biostimulants tested (mainly phosphites, amino acids and plant extracts) reduced the incidence of as up to 99% in leaves and 76% in fruits, as well as improved the fruit quality parameters. However, this effect was dependent on the class of biostimulant used, the way it was applied (isolated or mixture), and the year evaluated (variation in environmental conditions). Frequentes falhas de manejo da Sarna da Macieira (SDM) nos pomares, associadas aos problemas ambientais devido a utilização incorreta dos fungicidas, impulsionam o desenvolvimento de medidas alternativas. Assim, o objetivo do presente estudo foi verificar a possibilidade de uso dos bioestimulantes de forma isolada ou em mistura com fungicidas para o manejo da SDM. Para isto plantas de macieira ‘Gala’ foram pulverizadas de setembro a novembro dos anos de 2014 a 2018, entre um e dois dias antes de um período chuvoso com diferentes classes de bioestimulantes (aminoácidos, fosfitos, regulador de crescimento, fertilizantes foliares a base de extrato vegetal, algas e minerais). Alguns bioestimulantes testados reduziram a incidência da SDM em folhas e/ou frutos, bem como melhoraram os parâmetros de qualidade, no entanto este efeito foi dependente da classe de bioestimulante utilizado, forma que foi aplicado (isolado ou mistura), e ciclo da macieira avaliado.

Massive gene flow between crops and their wild relatives may threaten the genetic integrity of wild species. Such threats are now well documented, but little is known about indirect consequences involving the spillover of crop pathogens to wild plants or introgression between crop and wild pathogens. To address these questions, we used population genetics approaches, demographic inference and pathogenicity tests on host-pathogen pairs composed of wild or domesticated apple trees of Central Asia and their fungal pathogen, Venturia inaequalis, itself showing differentiated agricultural-type and wild-type populations. We confirmed the occurrence of gene flow from cultivated to wild apple trees in Asian forests, threatening the Asian wild apple genetic integrity. SNP markers and demographic modeling revealed the occurrence of a secondary contact followed by hybridization between agricultural-type and wild-type fungal pathogen populations, and the dispersal of the agricultural-type pathogen in wild forests. We detected a SNP predicting the ability of the fungus to parasitize the different host populations, which induced an early stop codon in a gene coding for a small secreted protein in the agricultural-type fungal population, thus representing a putative avirulence gene which function loss would enable to parasitize cultivated apples. Pathogenicity tests in fact revealed the pestification of V. inaequalis, with higher virulence of the agricultural-type population on both wild and domesticated trees. Our findings highlight the threat posed by cultivating a crop near its center of origin, with the invasion of a pestified pathogen on wild plants and introgression in the wild-type pathogen.

Ichneumonidae are solitary parasitoids that mainly attack larvae and pupae of Lepidoptera, Coleoptera and Hymenoptera, which constitute important agricultural pests. The objective of the present paper was to characterize the assemblage of Ichneumonidae associated to the conventional and organic cultivation of Guarana (Paullinia cupana) crop in Manaus City (Amazonas State, Brazil) with faunistic analysis. The samples were collected at Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), using Malaise and Moericke traps, between September 2012 and February 2013. We collected 296 specimens of Ichneumonidae, represented by 14 subfamilies, 41 genera and 63 morphospecies. The faunistic analysis revealed the predominance of rare and less frequent genera (54.2% in conventional and 47.1% in organic crop management). Venturia Schrottky was highlighted as superabundant, super frequent and constant (46.4% of the specimens) in conventional cultivation. In organic cultivation, Eiphosoma Cresson (15.6% of the specimens), Venturia (15.1%), Polycyrtidea Viereck (7%), Stethantyx Townes (6%), Enicospilus Stephens and Diapetimorpha Viereck (both 5.5%), Polycyrtus Spinola and Podogaster Brullé (both 5%) were more abundant, more frequent and constant. The observed differences reflect the type of crop management. Considering that organic crop management do not use agrochemicals, there is a greater diversification of the landscape. On the other hand, a reduction in richness and abundance has been observed in conventional crop management, due to its greater alteration and uniformity of the landscape. This study evidences a high number of rare, less frequent and accidental genera, and reveals the predominant groups in each crop cultivation system. RESUMO: Ichneumonidae são parasitoides solitários e atacam principalmente larvas e pupas de Lepidoptera, Coleoptera e Hymenoptera, que constituem importantes pragas agrícolas. O objetivo do trabalho foi caracterizar a assembleia de Ichneumonidae associada ao cultivo de guaraná (Paullinia cupana) de manejo convencional e orgânico, em Manaus (Amazonas, Brasil) por meio de análise faunística. As coletas foram realizadas na EMBRAPA, com o uso de armadilhas Malaise e Moericke, entre setembro de 2012 e fevereiro de 2013. Foram coletados 296 exemplares de Ichneumonidae, em 14 subfamílias, 41 gêneros e 63 morfoespécies. A análise faunística revelou predominância de gêneros raros e pouco frequentes (54,2% no manejo convencional e 47,1% no orgânico). Venturia Schrottky destacou-se no manejo convencional como superabundante, superfrequente e constante (46,4% dos exemplares). No manejo orgânico, Eiphosoma Cresson (15,6% dos exemplares), Venturia (15,1%), Polycyrtidea Viereck (7%), Stethantyx Townes (6%), Enicospilus Stephens e Diapetimorpha Viereck (ambos 5,5%), Polycyrtus Spinola e Podogaster Brullé (ambos 5%) foram muito abundantes, muito frequentes e constantes. As diferenças observadas refletem o tipo de manejo da cultura. No manejo orgânico, por não utilizar agroquímicos, há uma maior diversificação da paisagem. Já no manejo convencional há uma redução da riqueza e abundância, por possuir maior perturbação e uniformidade da paisagem. Este estudo evidenciou o elevado número de gêneros raros, pouco frequentes e acidentais e expôs os grupos predominantes em cada sistema de manejo.

There is an urgent need for novel, efficient and environmentally friendly strategies to control apple scab (Venturia inaequalis), for the purpose of reducing overall pesticide use. Fructans are recently emerging as promising &ldquo, priming&rdquo, compounds, standing out for their safety and low production costs. The objective of this work was to test a fructan-triggered defense in the leaves of apple seedlings. It was demonstrated that exogenous leaf spraying can reduce the development of apple scab disease symptoms. When evaluated macroscopically and by V. inaequalis-specific qPCR, levan-treated leaves showed a significant reduction of sporulation and V. inaequalis DNA in comparison to mock- and inulin-treated leaves, comparable to the levels in fosetyl-aluminum-treated leaves. Furthermore, we observed a significant reduction of in vitro mycelial growth of V. inaequalis on plates supplemented with levans when compared to controls, indicating a direct inhibition of fungal growth. Variations in endogenous sugar contents in the leaves were followed during priming and subsequent infection, revealing complex dynamics as a function of time and leaf ontogeny. Our data are discussed in view of the present theories on sugar signaling and fructan-based immunity, identifying areas for future research and highlighting the potential use of fructans in apple scab management in orchards.

There is an urgent need for novel, efficient and environmentally friendly strategies to control apple scab (Venturia inaequalis), for the purpose of reducing overall pesticide use. Fructans are recently emerging as promising “priming” compounds, standing out for their safety and low production costs. The objective of this work was to test a fructan-triggered defense in the leaves of apple seedlings. It was demonstrated that exogenous leaf spraying can reduce the development of apple scab disease symptoms. When evaluated macroscopically and by V. inaequalis-specific qPCR, levan-treated leaves showed a significant reduction of sporulation and V. inaequalis DNA in comparison to mock- and inulin-treated leaves, comparable to the levels in fosetyl-aluminum-treated leaves. Furthermore, we observed a significant reduction of in vitro mycelial growth of V. inaequalis on plates supplemented with levans when compared to controls, indicating a direct inhibition of fungal growth. Variations in endogenous sugar contents in the leaves were followed during priming and subsequent infection, revealing complex dynamics as a function of time and leaf ontogeny. Our data are discussed in view of the present theories on sugar signaling and fructan-based immunity, identifying areas for future research and highlighting the potential use of fructans in apple scab management in orchards.

Venturia inaequalis, an agent of apple scab, is the most important pathogen of Malus x domestica. Control measures against this pathogen rely on intensive phytosanitary programs based on predictive models to identify the meteorological conditions conducive to the primary infection. The detection of the pathogen in field, both in naturally infected symptomatic and asymptomatic leaves, is desirable. Loop-mediated isothermal amplification (LAMP) assays are profitable molecular diagnostic tools for the direct detection of pathogens in field. A LAMP assay for V. inaequalis has been designed on the elongation factor 1-alpha sequence. The validation of the LAMP assay was carried out following the international EPPO standard PM 7/98 in terms of specificity, sensitivity, repeatability and reproducibility. Specificity testing was performed using target and non-target species, such as phylogenetically related Venturia species and other pathogens commonly found in apple, resulting in positive amplification only for the target with a time to positive ranging from 20 to 30 min. Sensitivity testing was performed with serial dilutions of DNA of the target and by artificial inoculation of young apple leaves. The reliability of the LAMP assay as an early-detection tool and its user-friendly application make it suitable for the diagnosis of apple scab in the field.

Statistical methods revealed a close relationship between antifungal activity (suppression of the growth of the mycelium of the fungi of the speciesVenturia inaqualis,Aspergillus nigerandFusarium moniliforme) and the molecular structure of the substituted benzo-1-thiadiazoles and benzo-1-seleniumdiazoles. The molecular pseudopotential is used as the explanatory variable in the regression equations. It was established the threshold dependence of the antifungal activity on the pseudopotential of the molecule. The explanatory variable exceeding of its threshold value leads to a rapid linear increase in bioactivity for all species of fungi. Antifungal activity of drugs is low to the threshold value of the molecular pseudopotential and does not have a significant relationship with the variability of the molecular structure of the chemical compounds.

Two new Afrotropical ichneumon wasp species are described: Casinaria latericia Vas, sp. n. from Uganda, and Venturia mortifera Vas, sp. n. from Burundi. First records of Charops ater Szépligeti, 1908 from Burundi, Charops electrinus Vas, 2020 from Central African Republic, and Charops juliannae Vas, 2020 from Uganda are reported. With 2 figures.

A TaqMan quantitative PCR (qPCR) assay based on the translation elongation factor 1-α gene was developed for the quantification of Venturia inaequalis in leaves and fruits of Malus × domestica and in spore trap samples. The designed primers and hydrolysis probe amplified a specific 86-bp fragment for V. inaequalis. The specificity of the assay was tested using 35 strains of V. inaequalis and 20 different fungal species, including common pathogens of apple and other species of Venturia. The limit of detection was 20 fg, which is lower than a single genome of V. inaequalis. The selectivity of the assay was tested using DNA from three cultivars of Malus × domestica, and no influence on pathogen amplification was found. The assay was also validated for repeatability and reproducibility. With this assay, it was possible to detect and quantify V. inaequalis in four cultivars (Ambrosia, Florina, Golden Delicious, and Mondial Gala) in both symptomatic and asymptomatic leaves and in symptomatic Golden Delicious apple fruit stored for 2 months. Furthermore, the assay was successfully tested on spore trap samples originating from apple orchards. The quantification of the molecular assay when compared with the estimated number of V. inaequalis cells, using an optical microscope, showed a correlation coefficient of 0.8186. The developed technique could be used to detect V. inaequalis in asymptomatic samples without any cross-reaction with other fungal species. Furthermore, to improve the efficacy of disease management with a timely application of fungicides, this assay could be used for the analysis of spore trap samples by using an implemented extraction method.

Airborne mycofloral spores are important part of the fungal inocula responsible for various infections, decays and allergies in the environment. Unfortunately, the diversity, abundance and rhythm of seasonal occurrence are poorly known and studied in this part of the tropics. The aims of this study were to ascertain the airborne fungal spore diversity and their monthly and seasonal abundance at the different locations. The influence of some meteorological factors on 18 most abundant and fungal spore genera was under studied. The study was conducted in Enugu North using modified Tauber Traps at locations differing in urbanization for a period of 12 months. The results showed that 49 airborne fungal spore genera were identified which varied in abundance across the seasons, months and locations. The highest airborne fungal spore abundance and diversity were recorded during the rainy season, and the majority of the airborne spore genera had their peak frequencies in October, July and March. The highest spore abundance was recorded in Adani, but majority of the spore diversity had their maximum frequency of occurrence at Enugu Ezike and Adani. High fungal spore diversity and abundance were recorded more in higher-altitude locations, especially the most frequent and abundant airborne fungal spore genera such as Nigrospora, Endophragmiella, Ustilago, Botryodiplodia, Pithomyces and Venturia. Statistically, there were significant differences (p