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A series of novel porphyrin ligands and their zinc complexes with twelve long flexible chains have been synthesized and characterized by UV-Vis, IR, and 1H NMR spectra. Liquid-crystal properties of the compounds are studied by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Absorption spectra, luminescence spectra and fluorescence lifetime of the products are determined.

Silvery messerschmidia, Messerschmidia argentea (L.) Johnston, of the Boraginaceae, is indigenous to Taiwan and grown as an ornamental, for windbreaks, or as a shade tree. During the summer of 2005, a sudden wilt of 1-year-old plants was observed in a nursery in central Taiwan. Initial symptoms included stem necrosis at the collar, leaf yellowing, and tan discoloration of leaves. As stem necrosis progressed, infected plants wilted, defoliated, and died. Necrotic tissues were covered with whitish mycelium with clamp connections that formed reddish brown spherical (1 to 2.2 mm in diameter) sclerotia. A fungus was consistently recovered from the interface of diseased and healthy stem tissue, disinfested for 1 min in 0.5% NaOCl, and plated on Difco (Sparks, MD) potato dextrose agar (PDA) amended with 100 ppm of ampicillin. Pure cultures were prepared by transferring single hyphal tips to PDA, and Sclerotium rolfsii (Sacc.) was identified (1). Pathogenicity of two S. rolfsii isolates was confirmed by inoculating 3-month-old silvery messerschmidia seedlings grown in pots. Inoculum consisted of a single agar disk of a 7-day-old culture used per pot or a single sclerotium produced in 10 days on PDA and added per pot. Both the mycelium on the 0.5-cm-diameter agar plug and the sclerotium touched the base of the plant stem. Four plants were inoculated with mycelia, four with sclerotia, and four were noninoculated controls. All plants were kept in a growth chamber at 25 to 35°C with relative humidity of more than 95%. Initially, the basal stems were covered by whitish mycelia growth with a fanlike pattern from the inoculum, and brown, water-soaked necrotic lesions developed near the soil line. Inoculated plants developed symptoms within 4 days, wilted gradually in 7 days, and all were eventually killed in 11 days. Plants inoculated with sclerotia developed disease at a slower rate and control plants remained symptomless. Sclerotia developed on diseased tissues and S. rolfsii was reisolated. This disease has been observed on many species of plants (2), but to our knowledge, this is the first report of southern blight of silvery messerschmidia seedlings caused by S. rolfsii in Taiwan. References: (1) R. K. Jones and D. M. Benson, eds. Diseases of Woody Ornamentals and Trees in Nurseries. The American Phytopathological Society, St. Paul, MN, 2001. (2) Y. P. Tsai, ed. List of Plant Diseases in Taiwan. The Plant Protection Society of the Republic of China and The Phytopathological Society of the Republic of China, 1991.

White root rot is a serious soil-borne disease of several woods and crops. Recently, white root rot of tea shrubs and ornamental trees has increasingly been observed in Taiwan. Thirty-six isolates of white root rot pathogen, showing pear-shape swellings adjacent to the hyphal septa, had been isolated from samples of white root rot collected from Taiwan for about 4 years. The pathogen isolates produced Dematophora anamorph. Conidia of the pathogen were one-celled, hyaline, subglobal, with truncate base, 2.9-5.8 x 1.9-3.5 μM. Ascospore dimensions were in the range of 37.0-55.0 x 5.4-7.9 μM with a short, longitudinal and straight germ slit, which complied with Rosellinia necatrix. Based on molecular studies, the pathogen isolates collected from Taiwan except R701 were identified as R. nectarix. Isolate R701, which was relatively polymorphic in internal transcribed spacer DNA sequence than other isolates, was temporarily considered as R. necatrix-related pathogenic Rosellinia spp. All the tea cuttings (Camellia sinensis) inoculated with isolates developed typical white root rot symptoms. Pathogenicity tests demonstrated the presence of variation in virulence among the Rosellina isolates. Most of the R. necatrix isolates originating from Acer morrisonense were less virulent than those that originated from other hosts. The pathogenic Rosellinia spp., isolate R701, was also highly virulent to both cultivars of tea cuttings.

Since 2005, coconut fruits (Cocos nucifera L.) harvested from trees in southern Taiwan have shown symptoms of a fruit rot disease. The disease occurs only on harvested coconut fruits and is more serious during warmer seasons. Principal symptoms are blackening of the exocarps, mesocarps, and then the endocarps of coconut fruits from pedicel end or wounds on fruits. A fungus was consistently recovered from diseased fruits. Colonies on potato dextrose agar (PDA) were white, becoming black 1 to 2 days later, with a strong fruity aroma. The fungus produced two asexual spores, including phialospore-type conidia, which were hyaline to mid brown, cylindrical to somewhat oval and thick walled when mature, 8.5 to 16.0 × 4.7 to 6.7 μm, released from phialides measuring 80.0 to 155.0 × 5.0 to 7.8 μm, and chlamydospores, which were oval, black, 13.4 to 25.0 × 8.9 to 12.5 μm, and formed in short chains from specialized hyphal tips. Perithecia were produced after 2 months by mating isolates on coconut exocarp placed on PDA. Perithecia were brown, globose, 280 μm in diameter, with a 1,100-μm long neck. Ascospores generally were ellipsoid, but some were unequally bent, 12 × 3 μm. The temperature for hyphal growth of this fungus was 25 to 30°C, with a growth rate of 3.3 cm per day. It did not grow at temperatures lower than 10°C or higher than 35°C. On the basis of these characteristics, this fungus was identified as Ceratocystis paradoxa (Dade) C. Moreau (anamorph Thielaviopsis paradoxa (de Seynes) Höhn) (1). The internal transcribed spacer (ITS) region of mycelial DNA of two isolates was amplified with ITS5 and ITS4 primers and the PCR products were sequenced (GenBank Accession Nos. GU358207 and GU358206). BLAST analysis of both sequences showed 99% sequence similarity with C. paradoxa strain WIN(M) 925 (Accession No. DQ318203). Two of the isolates (BCRC 34425 and BCRC 34426) were deposited in the Bioresource Collection and Research Center, Hsinchu, Taiwan. Twenty-four detached healthy coconut fruits were inoculated by placing spore suspensions (1 × 105 spores/ml) of eight wild type isolates onto wounds created by removing the calyx. Symptoms similar to those observed in the field developed on inoculated fruits after incubating at room temperature for 10 days, but did not develop on six fruits that were wounded but not inoculated. The same pathogen was reisolated from the inoculated fruits but not the control fruits. C. paradoxa has been reported as causing disease of coconut fruits in Brazil (2), but to our knowledge, this is the first report of the disease in Taiwan. References: (1) G. Morgan-Jones. No. 143 in: CMI Descriptions of Pathogenic Fungi and Bacteria. Commonwealth Mycological Institute, Surrey, England, 1967. (2) V. Rossetti. “Crostas Pretas” das folhas e “Podridão Basal” dos frutos de coqueiro. O Biológico 21:54, 1955.

Japanese serissa (Serissa japonica (Thunb.) Thunb.) is a very popular ornamental in Taiwan. During the summer of 2005, serissa plants in a central Taiwan nursery had decaying roots, leaf yellowing, and were wilting. Wilted plants had white fan-like mycelium under the bark. The disease caused 70% loss of seedlings at the nursery. Associated synnemata were rigid, erect, dark, setaceous, 0.8 to 2.1 mm long, 90 to 200 μm wide, and tapering to enlarged whitish gray heads composed of geniculate conidiophores and conidia. Conidia were 3.1 to 5.8 × 2.6 to 3.4 μm, unicellular, hyaline, and subglobal with a truncated base. Root rots were washed, disinfested for 1 min in 0.5% NaOCl, cut into 3 mm3 pieces, plated on Merck (Darmstadt, Germany) potato dextrose agar (PDA) amended with 100 ppm of ampicillin (Sigma, St. Louis, MO), and incubated at 24°C in the dark until hyphae emerged. Single hyphal tips were transferred to PDA, and two isolates were established as pure cultures. Mycelia were cut, stained with 1% cotton blue in lactophenol, and pear-shaped hyphal swellings adjacent to the septa were observed. According to these hyphal, synnematal, and conidial characteristics, the fungus was identified as Dematophora necatrix Hartig, the anamorph of Rosellinia necatrix Prill. Inoculum for pathogenicity tests were produced on oat-wheat medium composed of 20 ml of oat grain and 20 ml of wheat grain, mixed, and soaked in water for 3 h. The grains were placed in 200-ml flasks, autoclaved at 121°C for 30 min, inoculated with two isolates of D. necatrix separately, and grown for 14 days. Six 3-month-old Japanese serissa seedlings were grown in pots. The grain inoculum was added to unsterilized field soil and the plants were transplanted into this mix. Control plants were transplanted into a similar mix without the inoculum. Two replicates were used for a total of 24 inoculated plants and 24 control plants. All plants were kept in a growth chamber at 25 to 35°C with 20 min of irrigation per day, 12 h of irradiation, and relative humidity at more than 95%. Inoculated plants developed root rots after 1 month, and after 4 months, all plants were dead, while control plants remained healthy. D. necatrix was reisolated, hyphal characteristics confirmed, and synnemata were observed on collars of dead plants. The teleomorph was not formed by our cultures, and the identification of Rosellinia necatrix was confirmed by molecular studies. The nuclear ribosomal internal transcribed spacer (ITS) amplified with two primers, ITS1 and ITS4, from our representative isolate demonstrated 99.63, 99.81, and 99.27% similarity to two R. necatrix isolates from Japan and one R. necatrix isolate from Italy, respectively. This disease has been reported on many species of plants (1), but to our knowledge, this is the first report of white root rot of Japanese serissa seedlings caused by R. necatrix in Taiwan. Reference: (1) S. T. Su et al. List of Plant Diseases in Taiwan. The Phytopathological Society of the Republic of China, 2002.