Sclerotinia sclerotiorum is a necrotrophic fungal pathogen causing white mold on many important economic crops. Recently, some mycoviruses such as S. sclerotiorum hypovirulence-associated DNA virus 1 (SsHADV-1) converted S. sclerotiorum into a beneficial symbiont that helps plants manage pathogens and other stresses. To explore the potential use of SsHADV-1 as a biocontrol agent in the United States and to test the efficacy of SsHADV-1-infected United States isolates in managing white mold and other crop diseases, SsHADV-1 was transferred from the Chinese strain DT-8 to United States isolates of S. sclerotiorum. SsHADV-1 is readily transmitted horizontally among United States isolates of S. sclerotiorum and consistently conferred hypovirulence to its host strains. Biopriming of dry bean seeds with hypovirulent S. sclerotiorum strains enhanced resistance to white mold, gray mold, and Rhizoctonia root rot. To investigate the underlying mechanisms, endophytic growth of hypovirulent S. sclerotiorum in dry beans was confirmed using PCR, and the expression of 12 plant defense-related genes were monitored before and after infection. The results indicated that the endophytic growth of SsHADV-1-infected strains in plants stimulated the expression of plant immunity pathway genes that assisted a rapid response from the plant to fungal infection. Finally, application of the seed biopriming technology with SsHADV-1-infected hypervirulent strain has promise for the biological control of several diseases of wheat, pea, and sunflower.

Trichosanthes kirilowii (Chinese cucumber) is one of the important perennial herbaceous vines in China, with putative pharmacological activities including anti-tumor and lowering blood lipids. In July 2022, T. kirilowii plants with brownish roots and chlorotic leaves were observed in several orchards in Qianshan, Anhui province, China (30°34'N, 116° 30'E). The disease incidence reached approximately 10% within an area spanning 20 ha, and was higher in poorly drained orchards. To investigate this root rot disease, five symptomatic plants were collected from the diseased orchards in Qianshan. Subsequently, small sections of the diseased roots were surface sterilized using 1% sodium hypochlorite and 75% ethanol for 45 seconds each. Then, sterilized roots were placed onto PDA (20% diced potato, 2% glucose, and 1.5% agar, and distilled water) and incubated at 28℃ in the dark for 6 days. A total of eight isolates with similar morphology were obtained and purified by single spore culturing. Two representative isolates (QSJ4 and QSJ5) were chosen for further analysis. When grown on PDA, the surface of each colony was white with dense aerial mycelium and pale orange color in the center with a white edge on the reverse side. Macroconidia produced on carnation leaf agar plates were falcate, slightly curved, and 3 to 5 septate, with papillate apical cells and indistinct basal cells. Macroconidia were 17.4-42.3 × 2.4-5.8 μm (n = 100). Microconidia were ellipsoidal in shape, slightly curved or not curved, and most were 1-septate, 9.6-16.7 × 1.5-3.8 μm (n = 40). The identity was determined by sequencing four loci (i. e., ITS, CAL, EF1-α and RPB2) from two representative isolates (Liu et al. 1999; O'Donnell et al. 1998, 2000; Reeb et al. 2004; White et al. 1990). Sequences were deposited in GenBank [ITS (OR267397, OR267398), CAL (OR296634, OR296635), EF1-α (OR296637, OR296638) and RPB2 (OR296640, OR296641)]. A phylogenetic analysis was performed with three loci (CAL, EF1-α, RPB2) comprising a concatenated dataset of 68 strains in the Fusarium incarnatum-equiseti species complex (Han et al., 2023). The results showed that isolates QSJ4 and QSJ5 clustered closely together with reference strains of F. sulawesiense. Pathogenicity tests were conducted by inoculating three-week-old healthy T. kirilowii seedings (cv. Wanlou No. 9) cultivated in substrate soil in pots with a diameter of 17 cm and a height of 10.5 cm. A 20 mL aliquot of spore suspension (106 conidia/mL) of F. sulawesiense was inoculated to the roots of potted seedlings by irrigation. Each strain was inoculated onto three seedlings. The potted seedlings were inoculated with sterile water as the negative control. Inoculated seedlings were incubated in a growth chamber at 25℃ and 75% relative humidity. After one week, typical symptoms of root necrosis and leaf chlorosis were observed on the inoculated seedlings. Disease symptoms were not observed on the control seedlings. All seedlings showing root necrosis and leaf chlorosis caused by the inoculations were subjected to fungal isolation, and the results showed that the reisolated colonies matched the inoculated ones for morphologies and ITS sequences. Fusarium sulawesiense has been previously reported to cause disease on Cucumis melo L. in Brazil (Medeiros Araujo et al. 2021), Musa acuminata Colla in south Sulawesi (Maryani et al. 2019), Luffa aegyptiaca Miller and Musa nana Lour. in China (Wang et al. 2019). To our knowledge, this is the first report of F. sulawesiense causing Fusarium root rot of T. kirilowii in China.

Background Pseudomonas syringae pv. actinidiae (Psa) is an important bacterial plant pathogen that causes severe damage to the kiwifruit industry worldwide. Three Psa strains were recently obtained from different kiwifruit orchards in Anhui Province, China. The present study mainly focused on the variations in virulence and genome characteristics of these strains based on the pathogenicity assays and comparative genomic analyses. Results Three strains were identified as biovar 3 (Psa3), along with strain QSY6 showing higher virulence than JZY2 and YXH1 in pathogenicity assays. The whole genome assembly revealed that each of the three strains had a circular chromosome and a complete plasmid. The chromosome sizes ranged from 6.5 to 6.6 Mb with a GC content of approximately 58.39 to 58.46%, and a predicted number of protein-coding sequences ranging from 5,884 to 6,019. The three strains clustered tightly with 8 Psa3 reference strains in terms of average nucleotide identity (ANI), whole-genome-based phylogenetic analysis, and pangenome analysis, while they were evolutionarily distinct from other biovars (Psa1 and Psa5). Variations were observed in the repertoire of effectors of the type III secretion system among all 15 strains. Moreover, synteny analysis of the three sequenced strains revealed eight genomic regions containing 308 genes exclusively present in the highly virulent strain QSY6. Further investigation of these genes showed that 16 virulence-related genes highlight several key factors, such as effector delivery systems (type III secretion systems) and adherence (type IV pilus), which might be crucial for the virulence of QSY6. Conclusion Three Psa strains were identified and showed variant virulence in kiwifruit plant. Complete genome sequences and comparative genomic analyses further provided a theoretical basis for the potential pathogenic factors responsible for kiwifruit bacterial canker.

The extracytoplasmic function (ECF) sigma factor AlgU is involved in the regulation of various virulence-related pathways in Pseudomonas syringae, especially alginate biosynthesis and motility, and the role of AlgU differs among P. syringae pathovars. However, to date, the mechanism of its regulation in virulence of P. syringae pv. actinidiae (Psa) is still unclear. ECF sigma factors are a class of alternative sigma factors that typically function with anti-sigma factors as part of cell-surface signaling systems. Under non-inducing conditions, AlgU remains inhibited by anti-sigma factors such as MucA and MucB. To investigate the function of AlgU in Psa, mutant strains lacking algU or lacking algU with mucA and mucB genes, as well as complementary and overexpression strains of algU were generated, respectively. The results showed that AlgU was highly conserved among P. syringae pathovars and positively regulated growth rate, pathogenicity, and resistance to osmotic and oxidative stress of Psa QSY6. While AlgU did not affect the motility and exopolysaccharide production of Psa, its abundant expression enhanced the swimming ability of QSY6 and reduced its production of extracellular polysaccharides. Furthermore, AlgU regulates a number of virulence-related factors, including the Hrp system, the type VI secretion system, and flagellar synthesis. Specifically, AlgU induced the expression of hrpL and hrpRS in vivo, and repressed the transcription of hrpL and tssC in vitro, while promoting the expression of hrpS, fliC, and tssJ. This study contributes to a better understanding of the mechanisms of virulence regulation of AlgU in Psa.

We report the discovery of a Sclerotinia sclerotiorum hypovirulence-associated DNA virus 1 (SsHADV-1) isolate, named SsHADV1_PO, from the fungus Penicillium olsonii isolated from Washington state, USA. The genome of SsHADV1_PO is 2,166 bp and contains two open reading frames, with more than 98% nucleotide identity with respect to reported SsHADV-1 isolates.

Colletotrichum fructicola infects pear leaves, resulting in two major symptoms: tiny black spots (TS) followed by severe early defoliation and big necrotic lesions (BnL) without apparent damage depending on the pathotypes. How the same fungal species causes different symptoms remains unclear. To understand the molecular mechanism underlying the resulting diseases and the diverse symptoms, two C. fructicola pathogenetic strains (PAFQ31 and PAFQ32 responsible for TS and BnL symptoms, respectively) were inoculated on Pyrus pyrifolia leaves and subjected to transcriptome sequencing at the quiescent stage (QS) and necrotrophic stage (NS), respectively. In planta, the genes involved in the salicylic acid (SA) signaling pathway were upregulated at the NS caused by the infection of each strain. In contrast, the ethylene (ET), abscisic acid (ABA), and jasmonic acid (JA) signaling pathways were specifically related to the TS symptoms caused by the infection of strain PAFQ31, corresponding to the yellowish and early defoliation symptoms triggered by the strain infection. Correspondingly, SA was accumulated in similar levels in the leaves infected by each strain at NS, but JA was significantly higher in the PAFQ31-infected as measured using high-performance liquid chromatography. Weighted gene co-expression network analysis also reveals specific genes, pathways, phytohormones, and transcription factors (TFs) associated with the PAFQ31-associated early defoliation. Taken together, these data suggest that specific metabolic pathways were regulated in P. pyrifolia in response to the infection of two C. fructicola pathotypes resulting in the diverse symptoms: JA, ET, and ABA accumulated in the PAFQ31-infected leaves, which negatively affected the chlorophyll metabolism and photosynthesis pathways while positively affecting the expression of senescence-associated TFs and genes, resulted in leaf yellowing and defoliation; whereas SA inhibited JA-induced gene expression in the PAFQ32-infected leaves, which led to hypersensitive response-like reaction and BnL symptoms.

A scenario proposing that dsRNA viruses evolved from +ssRNA viruses is still considered controversial due to intergroup knowledge gaps in virus diversity. Recently, polymycoviruses and hadakaviruses were found as intermediate dsRNA and +ssRNA stages, respectively, between +ssRNA and dsRNA viruses.

Species of Diaporthe (syn. Phomopsis) are important endophytes, saprobes and pathogens, infecting a wide range of plants and resulting in important crop diseases. However, the species occurring on pear remain largely unresolved. In this study, a total of 453 Diaporthe isolates were obtained from branches of Pyrus plants (including P. bretschneideri, P. communis, P. pyrifolia and P. ussuriensis collected from 12 provinces in China) showing shoot canker symptoms. Phylogenetic analyses based on five loci (ITS, TEF, CAL, HIS, and TUB) coupled with morphology of 113 representative isolates revealed that 19 Diaporthe species were isolated, representing 13 known species (including D. caryae, D. cercidis, D. citrichinensis, D. eres, D. fusicola, D. ganjae, D. hongkongensis, D. padina, D. pescicola, D. sojae, D. taoicola, D. unshiuensis and D. velutina) and six new species described here as D. acuta, D. chongqingensis, D. fulvicolor, D. parvae, D. spinosa and D. zaobaisu. Although Koch's postulates confirmed all species to be pathogenic, a high degree of variation in aggressiveness was observed. Moreover, these species have a high diversity, plasticity, and prevalence related to the geographical location and pear species involved.

[目的]明确我国南方梨产区造成早期落叶的果生炭疽菌(Colletotrichum fructicola)的致病力分化状况并建立其室内快速测定方法.[方法]以梨的枝条、叶片和果实为材料,采用不同方法造成伤口后接种果生炭疽菌的强致病力菌株PAFQ32,通过比较各处理的测定效果筛选其室内快速测定方法,并对供试菌株的致病力进行观测和致病类型划分,分析不同菌株致病力分化与其地理来源之间的相关性.[结果]采用梨枝条、叶片和果实对果生炭疽菌致病力的观测结果显示,梨叶片经针刺后接种菌丝块的测定效果明显优于其他处理.供试菌株致病力的测定结果表明,来源于我国南方梨产区的111个果生炭疽菌菌株其致病力可划分为强、中、弱3个类型,其中强致病力菌株17个(15.3％);中等致病力菌株89个(80.2％);弱致病力菌株5个(4.5％).不同地理来源的果生炭疽菌菌株,其致病类型的分布比例有异.[结论]果生炭疽菌的菌丝块针刺接种梨叶片的方法,可用于其致病力的室内快速测定.来源于我国南方梨产区导致早期落叶的果生炭疽菌存在明显的致病力分化,以中等致病力菌株为优势群体.

[目的]明确近年在福建砂梨产区新发生的梨急性花枯病的病原菌种类.[方法]从产区采集显现急性花枯症状的'翠冠'梨病样品进行组织分离,并利用形态学和分子生物学相结合的方法对获得的菌株进行种类鉴定和致病性验证.[结果]通过组织分离和纯化,并根据其菌落形态特征从福建砂梨急性花枯病样品中获得3 1个刺盘孢属(Colletotrichum)菌株.选取其中的14个代表菌株进行形态学观察和多基因(ITS、ACT、TUB、CHS-1及GAPDH)系统发育分析的结果显示,它们均为松针刺盘孢(C.fioriniae).在一周花龄的砂梨(品种'丰水梨')、西洋梨(品种'三季梨')和秋子梨(品种'南果梨')的离体花序上喷雾接种代表菌株(CFZH1、CFZH6、CFZH 15)分生孢子悬浮液的结果显示,均产生有急性花枯症状,平均发病率分别95.8％、63.9％和81.3％.[结论]福建砂梨产区导致梨急性花枯病的病原菌为松针刺盘孢(C.fioriniae).本研究是福建砂梨产区松针刺盘孢引起梨花枯死的首次报道.

Botryosphaeria dothidea is an important pathogenic fungus that causes serious diseases in fruits and trunks of many wood plant species worldwide. In this study, 28 B. dothidea strains isolated from pear trunk samples showing stem wart or canker symptoms were used to detect double-stranded RNA (dsRNA) viruses. The dsRNA bands with the size of ~ 1.0 to ~ 6.0 kbp were examined from ten strains. Here, we reported a novel dsRNA mycovirus, tentatively named as Botryosphaeria dothidea victorivirus 2 (BdVV2), isolated from the B. dothidea strain MSD53. BdVV2 contained spherical virions that were ~ 38 nm in diameter consisting of a single linear dsRNA genome of 5,090 bp in length. The BdVV2 genome contained two overlapping open reading frames (ORFs) encoding a putative coat protein (CP) and an RNA-dependent RNA polymerase (RdRp), which shared significant amino acid identities of 68% and 60% with the corresponding proteins of Sphaeropsis sapinea RNA viruses 1 (SsRV1). Phylogenetic analyses based on the aa sequences of CP and RdRp both showed that BdVV2 was phylogenetically related to the members of the genus Victorivirus in the family Totiviridae. BdVV2 is thus a novel victorivirus isolated from the phytopathogenic fungus B. dothidea.

梨果生刺盘孢的2种致病型菌株F J-85(产生黑点症状)和菌株FJ-11-2(产生坏死斑症状)的子囊孢子单孢培养均可产生正、负2种类型的单孢菌系.正型单孢菌系菌落浅白色,其上形成的子囊孢子再培养,可形成正、负2种类型的单孢菌系;负型单孢菌系菌落深灰色,其上形成的子囊孢子再培养,只形成负型一种单孢菌系.2个菌株的单孢菌系中,负型的比例明显多于正型.2种类型的单孢菌系对峙培养,在菌落内及菌落交界处均可形成子囊壳,而同种类型的单孢菌系对峙培养仅在菌落内产生子囊壳.结果表明同种类型的单孢菌系可同宗配合,而正、负2种类型的单孢菌系还可异宗配合.正型单孢菌系的致病力与原始菌株相近,而负型单孢菌系较原始菌株弱.2个菌株的单孢菌系在翠冠梨上引起的症状差异与其原始菌株相同.研究结果为解析梨果生刺盘孢的有性生殖与致病的关系提供了新的有用信息.

A novel hepta-segmented double-stranded RNA (dsRNA) virus was isolated and characterized from the strain FJ-4 of the phytopathogenic fungus Colletotrichum fructicola, and was named Colletotrichum fructicola chrysovirus 1 (CfCV1). The full-length cDNAs of dsRNA1-7 were 3620, 2801, 2687, 2437, 1750, 1536, and 1211 bp, respectively. The 5 '- and 3 '-untranslated regions of the seven dsRNAs share highly similar internal sequence and contain conserved sequence stretches, indicating that they have a common virus origin. The 5 '- and 3 '-UTRs of the seven dsRNAs were predicted to fold into stable stem-loop structures. CfCV1 contains spherical virions that are 35 nm in diameter consisting of seven segments. The largest dsRNA of CfCV1 encodes an RNA-dependent RNA polymerase (RdRp), and the second dsRNA encodes a viral capsid protein (CP). The dsRNA5 encodes a C2H2-type zinc finger protein containing an R-rich region and a G-rich region. The smallest dsRNA is a satellite-like RNA. The functions of the other proteins encoded by dsRNA3, dsRNA4, dsRNA6 are unknown. Phylogenetic analysis, based on RdRp and CP, indicated that CfCV1 is phylogenetically related to Botryosphaeria dothidea chrysovirus 1 (BdCV1), and Penicillium janczewskii chrysovirus 2 (PjCV2), a cluster of an independent cluster II group in the family Chrysoviridae. Importantly, all the seven segments of CfCV1 were transmitted successfully to other virus-free strains with an all-or-none fashion. CfCV1 exerts minor influence on the growth of C. fructicola but can confer hypovirulence to the fungal host. To our knowledge, this is the first report of a hepta-segmented tentative chrysovirus in C. fructicola.

Colletotrichum species are plant pathogens, saprobes, and endophytes on a range of economically important hosts. However, the species occurring on pear remain largely unresolved. To determine the morphology, phylogeny and biology of Colletotrichum species associated with Pyrus plants, a total of 295 samples were collected from cultivated pear species (including P. pyrifolia, P. bretschneideri, and P. communis) from seven major pear-cultivation provinces in China. The pear leaves and fruits affected by anthracnose were sampled and subjected to fungus isolation, resulting in a total of 488 Colletotrichum isolates. Phylogenetic analyses based on six loci (ACT, TUB2, CAL, CHS-1, GAPDH, and ITS) coupled with morphology of 90 representative isolates revealed that they belong to 10 known Colletotrichum species, including C. aenigma, C. citricola, C. conoides, C. fioriniae, C. fructicola, C. gloeosporioides, C. karstii, C. plurivorum, C. siamense, C. wuxiense, and two novel species, described here as C. jinshuiense and C. pyrifoliae. Of these, C. fructicola was the most dominant, occurring on P. pyrifolia and P. bretschneideri in all surveyed provinces except in Shandong, where C. siamense was dominant. In contrast, only C. siamense and C. fioriniae were isolated from P. communis, with the former being dominant. In order to prove Koch's postulates, pathogenicity tests on pear leaves and fruits revealed a broad diversity in pathogenicity and aggressiveness among the species and isolates, of which C. citricola, C. jinshuiense, C. pyrifoliae, and C. conoides appeared to be organ-specific on either leaves or fruits. This study also represents the first reports of C. citricola, C. conoides, C. karstii, C. plurivorum, C. siamense, and C. wuxiense causing anthracnose on pear.

Alternaria fungi are important pathogens infecting a wide variety of organisms. Here, we report a novel double-stranded RNA (dsRNA) mycovirus named Alternaria botybirnavirus 1 (ABRV1) isolated from a phytopathogenic Alternaria sp. strain (SCFS-3) infecting a pear tree in China. ABRV1 has two dsRNA components (dsRNAs 1 and 2) with the sizes of 6,188 and 5,903 bp, containing two putative open reading frames encoding two polyproteins (202 and 192 kDa, respectively). The polyprotein encoded by ABRV1 dsRNA1 shares 41% amino acid (aa) sequence identity with the one encoded by dsRNA2 (instead of dsRNA1) of Sclerotinia sclerotiorum botybirnavirus 1 (SsBRV1). Conversely, the polyprotein encoded by ABRV1 dsRNA2 shares 46% aa sequence identity with the one (i.e., cap-pol fusion protein) encoded by SsBRV1 dsRNA1. ABRV1 has isometric spherical virus particles (~40 nm in diameter), putatively composed of the 60-, 70- and 80-kDa structural proteins. The genomic organization and phylogenetic analyses revealed that ABRV1 belongs to a newly proposed family "Botybirnaviridae", and to our knowledge, this is the first report of a botybirnavirus infecting an Alternaria sp. strain.

HomePlant DiseaseVol. 101, No. 3First Report of Diaporthe tulliensis and Diaporthe actinidiae Causing Kiwifruit Stem Canker in Hubei and Anhui Provinces, China PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Diaporthe tulliensis and Diaporthe actinidiae Causing Kiwifruit Stem Canker in Hubei and Anhui Provinces, ChinaQ. Bai, G. P. Wang, N. Hong, Y. S. Guo, and M. FuQ. BaiSearch for more papers by this author, G. P. WangSearch for more papers by this author, N. HongSearch for more papers by this author, Y. S. GuoSearch for more papers by this author, and M. FuSearch for more papers by this authorAffiliationsAuthors and Affiliations Q. Bai G. P. Wang N. Hong , National Key Laboratory of Agromicrobiology, Huazhong Agricultural University, Wuhan, Hubei 430070, China Y. S. Guo M. Fu , The Key Laboratory of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan, Hubei 430070, China. Published Online:10 Jan 2017https://doi.org/10.1094/PDIS-10-16-1445-PDNAboutSectionsSupplemental ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Diaporthe (anamorph: Phomopsis) spp. are frequently associated with stem canker, fruit rot, and leaf spots of kiwifruit (Actinidia spp.) worldwide (Auger et al. 2013; Díaz et al. 2014; Lee et al. 2001). From May to July 2015, several plants of Actinidia chinensis showing severe stem cankers were observed at two orchards in Hubei and Anhui provinces in China. The cankered areas had red-brown soft skin, shoots showing blight, and some trees eventually died. Bark tissues (<5 mm2) were excised from three diseased stems, disinfected with 75% ethanol, and cultured on potato dextrose agar (PDA) at 25°C. In all, 36 isolates showing colony features of Diaporthe spp. were recovered from the samples. Three isolates (named LP-1, LP-2, and WAI-1) representing the different morphological groups were selected for characterization. The colony LP-1 was initially white, and produced yellowish-green pigments at 7 days of incubation. The colonies LP-2 and WAI-1 were grayish during the same period. LP-1 and WAI-1 produced only α-conidia, measuring 3.7 to 6.5 × 1.0 to 2.6 μm and 4.9 to 8.1 × 1.7 to 3.2 μm, respectively. Isolate LP-2 produced α-conidia measuring 4.2 to 9.0 × 1.7 to 3.2 μm and β-conidia measuring 10.9 to 19.5 × 0.5 to 1.5 μm. All α-conidia were one-celled, hyaline, fusiform, and biguttulate while β-conidia were one-celled, hyaline, and filiform with straight or curved ends. The internal transcribed spacer (ITS) and translational elongation factor subunit 1-α gene (EF1α) of these isolates were amplified and sequenced using primer sets ITS1/ITS4 and EF1-728F/EF1-986R (Bai et al. 2015). The three isolates LP-1, LP-2, and WAI-1 (GenBank accession nos. KX457967 to 69 for ITS and KX457964 to 66 for EF1-α) showed 99 and 97% matches for D. tulliensis (KR936130 of ITS, KR936133 of EF1-α), 98 and 99% for D. actinidiae (KT163360 of ITS, KC145941 [but labeled as “unverified” in GenBank] of EF1-α), and 99% for both ITS and EF1-α of D. eres (FJ478132 and JN192170), respectively, using GenBank. Based on their morphology and molecular identification, LP-1, LP-2, and WAI-1 were identified as D. tulliensis, D. actinidiae, and D. eres, respectively. PDA plugs (5 mm2) from growing colonies (uncolonized for controls) were placed onto the wounds of six detached green shoots, of fully expanded leaves, and of mature fruits of A. chinensis (cv. Jinkui). For each shoot and fruit, a 5-mm hole was made with a cork borer, and each leaf was wounded at two areas (one for control) beside the main vein with a 0.2-mm needle. At 7 days post inoculation, LP-1, LP-2, and WAI-1 induced shoot cankers of 28.67 ± 2.65 mm, 22.0 0± 2.66 mm, and 4.42 ± 0.96 mm in length and lesions on fruits of 47.25 ± 0.30 × 36.20 ± 0.90, 36.13 ± 3.93 × 27.17 ± 2.59, and 20.80 ± 3.52 × 16.60 ± 3.25 mm, respectively. However, on detached leaves, only isolate LP-1 induced lesions, having 22.25 ± 1.30 mm in diameter. The fungi reisolated from the diseased tissues were morphologically similar to the inoculated isolates. The pathogen was not isolated from the controls. These results indicate that D. tulliensis isolate LP-1 and D. actinidiae isolate LP-2 were highly virulent on kiwifruit shoots and fruits, whereas D. eres isolate WAI-1 had low virulence on these tissues. D. actinidiae was reported causing fruit rot of Actinidiae spp. (Lee et al. 2001; Sommer and Beraha 1975), but this is the first report of D. actinidiae inducing stem canker of kiwifruit in China, as well as the first report of D. tulliensis infecting kiwifruit. This study provides important information for the early control of kiwifruit fungal diseases. Larger scale surveys should be conducted to obtain a better understanding of Diaporthe spp. infecting kiwifruit.References:Auger, J., et al. 2013. Plant Dis. 97:843. https://doi.org/10.1094/PDIS-10-12-0990-PDN Link, ISI, Google ScholarBai, Q., et al. 2015. Plant Dis. 99:1704. https://doi.org/10.1094/PDIS-03-15-0259-RE Link, ISI, Google ScholarDíaz, G. A., et al. 2014. Plant Dis. 98:1274. https://doi.org/10.1094/PDIS-02-14-0183-PDN Link, ISI, Google ScholarLee, J. G., et al. 2001. Plant Pathol. 17:110. Google ScholarSommer, N. F., and Beraha, L. 1975. Mycologia 67:650. https://doi.org/10.2307/3758400 Crossref, ISI, Google ScholarDetailsFiguresLiterature CitedRelated Vol. 101, No. 3 March 2017SubscribeISSN:0191-2917e-ISSN:1943-7692 Metrics Article History Issue Date: 9 Feb 2017Published: 10 Jan 2017First Look: 21 Nov 2016Accepted: 11 Nov 2016 Page: 508 Information© 2017 The American Phytopathological SocietyCited byFirst Report of Stem Canker Caused by Diaporthe tulliensis on Jasmine in TaiwanChing-Ching Hsu, Hui-Yu Hsiao, Tung-Ching Huang, and Yuan-Min Shen10 February 2023 | Plant Disease, Vol. 107, No. 2Introduction and multiplex management strategies of postharvest fungal diseases of kiwifruit: A reviewBiological Control, Vol. 176Early warning of Diaporthe infection in kiwifruit soft rot by plasmonic dimer-enhanced Raman spectroscopyiScience, Vol. 25, No. 12First Report of Leaf Spot Caused by Colletotrichum fructicola on Kiwifruit in ChinaLu Huang, Jing Sheng, Wenpeng Song, Die Zheng, Shengyan Song, Xiaoting Xu, Jiuming Yu, Qianwen Liu, Yongsheng Liu, and Wei Tang16 August 2022 | Plant Disease, Vol. 106, No. 10Leaf Spots on Bodhi Tree (Ficus religiosa) Caused by Diaporthe tulliensisKe Yu Li, Jing Jing Liang, Yi Feng Peng, Xiu Fang Ling, Yan Ting Cai, and Run Hua Yi16 August 2022 | Plant Disease, Vol. 106, No. 10Diaporthe actinidiae (stem-end rot of kiwi fruit)CABI Compendium, Vol. CABI CompendiumFirst Report of Leaf Spot Caused by Diaporthe tulliensis on Boston Ivy (Parthenocissus tricuspidata) in TaiwanCheng-Chun Huang, Hsien-Hao Liu, Ping-Hu Wu, and Hao-Xun Chang27 September 2021 | Plant Disease, Vol. 105, No. 9Molecular Phylogenetic Diversity and Biological Characterization of Diaporthe Species Associated with Leaf Spots of Camellia sinensis in Taiwan14 July 2021 | Plants, Vol. 10, No. 7Identification and Pathogenicity of Diplodia, Neofusicoccum, Cadophora, and Diaporthe Species Associated with Cordon Dieback in Kiwifruit cultivar Hayward in Central ChileGonzalo A. 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A novel double-stranded RNA (dsRNA) virus, designated as Botryosphaeria dothidea RNA virus 1 (BdRV1), isolated from a hypovirulent strain YZN115 of Botryosphaeria dothidea was biologically and molecularly characterized. The genome of BdRV1 comprises of five dsRNAs. Each dsRNA contains a single open reading frame. The proteins encoded by dsRNA1-4 shared significant amino acid identities of 55%, 47%, 43% and 53% with the corresponding proteins of Aspergillus fumigatus tetramycovirus-1. DsRNA1, 3, and 4 of BdRV1 encoded an RNA-dependent RNA polymerase, a viral methyltransferase, and a P-A-S-rich protein, respectively. Function of proteins encoded by the dsRNA2 and dsRNA5 were unknown. BdRV1 conferred hypovirulence for its host and could be transmitted through conidia and hyphae contact.