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The climbing vine, Vitis heyneana Roem. & Schult, is a member of the grape family endemic to Asia. Its fruits are used in wine production, and its roots, stems, and leaves can be used in medicinal materials. This plant is grown in Southwest China, as well as in India, Bhutan, and Nepal. Mulao Autonomous County in Guangxi Province is the only artificial cultivation area in China. During the summer of 2013, a panicle blight and leaf spot were detected on V. heyneana on four farms in Mulao Autonomous County. The symptoms were observed from the onset of florescence through fruit harvest. Brown lesions initially appeared at the base of a panicle and then extended to the whole panicle, finally causing the panicle to die and fruit to drop. When the disease developed on leaves, the symptom initially appeared as small dark brown circular spots, later enlarging into irregular spots (average diameter 6 mm) with a light brown center and dark brown rim. With severe disease, some individual leaves were affected by numerous spots, leading to premature senescence. Small sections of diseased tissue excised from 10 panicle and 10 leaf samples were plated on potato dextrose agar (PDA) and incubated at 28°C. Fungal colonies developed, initially with abundant white aerial mycelium, which turned olivaceous gray after 5 days and formed black pycnidia after 25 days. The conidia were hyaline, ellipsoidal to fusiform, externally smooth, thin-walled, and nonseptate. Thirty conidia were measured; the dimensions were 12.0 to 17.5 × 4.0 to 6.0 μm. Morphological characteristics of the isolates were similar to the descriptions of Neofusicoccum parvum (3). The isolate MPT-1 was selected as a representative for molecular identification. Genomic DNA was extracted and used for PCR to amplify the internal transcribed spacer (ITS) region and partial translation elongation factor 1-alpha (EF1-α) gene, using primers ITS1/ITS4 and EF1-728F/EF1-986R, respectively. The obtained ITS sequence (GenBank Accession No. KJ599627) and EF1-α sequence (KM921768) showed >99% homology with several GenBank sequences of N. parvum. Morphological and molecular results confirmed the isolate as N. parvum. For pathogenicity tests, detached, young healthy panicles and leaves of V. heyneana were surface-sterilized, wounded by sterile needle, and inoculated with mycelial plugs (3 mm in diameter) of four N. parvum isolates. Ten panicles and 10 leaves were used for every isolate. Control panicles and leaves were treated with sterile PDA plugs. All the samples were placed in a humid chamber (RH 90%, 28°C, 12 h of light) for 3 days. Symptoms similar to those observed in the field developed on all panicles and leaves inoculated with N. parvum isolates. N. parvum was reisolated from all inoculated, symptomatic tissues. The controls remained symptomless. N. parvum has been reported to cause trunk canker on V. vinifera (2), dieback on Cupressus funebris (3), and a leaf spot on Myristica fragrans (1). To our knowledge, this is the first report of N. parvum causing panicle blight and leaf spot on V. heyneana in China. Panicle blight caused a large number of fruits to drop and reduced the yield seriously. Some effective measures should be taken to control this disease. References: (1) V. Jayakumar et al. New Dis. Rep. 23:19, 2011. (2) J. Kaliternam et al. Plant Dis. 97:1656, 2013. (3) S. B. Li et al. Plant Dis. 94:641, 2010.

Akebia species have been used for centuries in medicinal practices in a few Asian countries such as China and Japan. The dried stems of Akebia trifoliata are known as mutong in the Chinese pharmacopoeia (4) and mokutsu in Kampo, the traditional Chinese medicine developed in Japan (2). In China, the plant is grown in the provinces of Shandong, Hebei, Shanxi, Henan, Gansu, and some provinces in the south of the Yangtze River basin. During the summer of 2012, a leaf spot disease was detected on A. trifoliata grown in Nanning, Guangxi, China. The disease occurred and spread rapidly in July under conditions of high temperature and high humidity. The symptoms appeared on three sites that we inspected; disease incidences were higher than 80%. Initial symptoms consisted of small (less than 5 mm in diameter), circular, purple-brown leaf spots. Spots later enlarged and became elliptical, circular, or irregular with gray-white centers and dark brown rims. The centers were slightly concave. The spots could coalesce with each other, resulting in leaf desiccation and wilting. A fungal isolate was obtained from symptomatic leaf tissue that taken from a field (22°50'N, 108°22'E) in Nanning, Guangxi, China. Single-spore culture of the isolate was incubated on potato dextrose agar (PDA) for 7 days in the dark at 28°C. Conidiophores were straight to slightly curved, unbranched, and pale brown. Conidia (19.0 to 140.5 μm long and 7.0 to 11.0 μm wide) were formed singly or in chains, obclavate to cylindrical, straight or curved, pale brown, with a rounded apex and truncate base, and 1 to 13 pseudosepta. Morphological characteristics of the isolate were similar to the descriptions of Corynespora cassiicola (Berk. & M.A. Curtis) C.T. Wei (1). Genomic DNA of the isolate was extracted and used for PCR amplification of rDNA-ITS (internal transcribed spacer) sequence with primers ITS1 and ITS4. The PCR products were purified and sequenced. The sequence (GenBank Accession No. KC977496) was used in BLAST searches to interrogate GenBank for sequence similarity. High sequence similarity of 100% was obtained with several C. cassiicola strains. Pathogenicity of the isolate was investigated to demonstrate Koch's postulate. Young, healthy, fully expanded green leaves of A. trifoliata were surface sterilized. Fifteen leaves were inoculated with 10-μl drops of conidia suspension (10 5 conidia per ml) and 10 leaves were inoculated with the same volume of sterile water to serve as controls. All the leaves were placed in a humid chamber for 5 days. Spots with similar symptoms to those observed in the field developed on all inoculated leaves. The pathogen was reisolated and identified as C. cassiicola. The controls remained symptomless. According to previous reports, A. trifoliata was infected by Alternaria tenuissima in China and by Colletotrichum acutatum in Japan (3). To our knowledge, this is the first report of C. cassiicola found on Akebia species worldwide. Furthermore, this new disease primarily affects plantations and reduces the quality and yield of the medicine. Some effective measures should be taken to control this disease. References: (1) M. B. Ellis and P. Holliday. CMI Description of Pathogenic Fungi and Bacteria, 303, 1971. (2) F. Kitaoka et al. J. Nat. Med. 63:374, 2009. (3) Y. Kobayshi et al. J. Gen. Plant Pathol. 70:295, 2004. (4) L. Li et al. HortScience 45:4, 2010.

Mucuna pruriens is a tropical legume known as velvet bean. It has many traditional and medicinal usages in treating Parkinson's disease (1), abdominal pain, cholera, infertility, scorpion bites, diabetes (3) and is found in tropical Africa, India, the Caribbean and China. During the fall of 2011, the velvet bean plants in Longan County, Guangxi, China, were damaged by a leaf disease previously unreported in China. Field inspections revealed disease incidences as high as 80%. Symptoms consisted of large spots developing between the leaf veins that ranged in length from 1 to 3 cm. Spots were dark brown, generally rectangular, and were visible from both sides of the leaf. Lots of black mycelia and conidia were found on the backs of the lesions. Lesions typically expanded and affected the entire leaf, resulting in leaves withered and killed. An Alternaria sp. having conidia with prominent beaks and spores produced singly was consistently observed on and isolated from symptomatic leaf tissue. The conidia body was brown, ovoid, obclavate, muriform, and septate, with transverse and longitudinal septa that varied from 6 to 9 and 0 to 2, respectively, and its dimensions varied from 60 to 120 × 15 to 20 μm. The beaks were 10 to 70 × 3 to 6 μm and were filamentous, slender, and unbranched. Pure culture of the fungus was made from a single spore. DNA was extracted and used in an internal transcribed spacer (ITS) PCR used ITS1 and ITS4 primers. The PCR products were purified and sequenced. The sequences were used in BLAST searches to interrogate the GenBank for sequence similarity. High sequence similarity of 100% was obtained with Alternaria porri isolate AP-18. Based on the morphological and molecular characterization, the isolate was identified as A. porri (Ellis) Ciferri (GenBank Accession No. JX556683) (2). The pathogenicity of five isolates was investigated to demonstrate Koch's postulates. Forty 8-week-old seedlings of M. pruriens, without wounding on their leaves, were sprayed with the spore suspension (10 5 spores per ml), prepared by using 10-day-old cultures of the isolates grown on potato dextrose agar at 28°C in the dark. Every plant was sprayed with 4 ml of spore suspension. The inoculated plants were incubated in a humid chamber for 48 h and then maintained in a greenhouse. After 5 to 7 days, leaf spots similar to those observed in the field developed on all inoculated plants. The pathogen was reisolated and identified as A. porri. Control plants sprayed with distilled water remained symptomless. The inoculation test was repeated and results were the same. Because A. porri was reported to infect plants of Allium spp and cause purple blotch, we also inoculated this isolate to small onion plants, and the symptoms of purple blotch appeared after 13 days at 25 to 28°C in a greenhouse. To our knowledge, this is the first report of leaf spot caused by A. porri on velvet bean in China. References: (1) R. Katzenschlager et al. J. Neurol. Neurosurg Psychiatry. 75:1672, 2004. (2) S. T. Koike and D. H. Henderson. Plant Dis. 82:710, 1998. (3) S. O. Majekodunmi et al. Asian Pac. J. Trop. Med. 4:632, 2011.

We determined that the methanol extract of Toxicodendron sylvestre could significantly inhibit Ralstonia solanacearum in vitro and in planta. One compound responsible for the antibacterial activity was isolated from the ethyl ether extract and identified as methyl gallate (MG) based on its 1 H and 13 C nuclear magnetic resonance data as well as mass spectroscopy. MG displayed broad-spectrum activity against plant-pathogenic bacteria, and strong inhibitory effects on the growth of plant-pathogenic oomycetes. The half inhibition concentration of MG on R. solanacearum was 8.3 mg/liter, which was tested by the agar dilution method. Disease control trials in planta showed that both natural and synthetic MG could effectively reduce the incidence of tomato bacterial wilt, and there was no significant difference between them in control efficacy. This is the first report on the use of MG for the control of a plant bacterial disease. Because of its broad-spectrum antimicrobial activity and significant control efficacy on tomato bacterial wilt in planta, MG shows potential to be used as a bactericide to control plant bacterial wilt.