First Report of Colletotrichum sansevieriae Causing Anthracnose of Sansevieria trifasciata in Florida

Sansevieria Thunberg, a member of the Agavaceae, contains around 60 species indigenous to Africa, Arabia, and India. Several species and their cultivars are commercially produced for use as interior and landscape foliage plants. During August 2010, several local nurseries submitted Sansevieria trifasciata samples to the Florida Extension Plant Diagnostic Clinic in Homestead. Leaves had round, water-soaked lesions and as the disease progressed, lesions rapidly enlarged and coalesced, resulting in severe leaf blight. Both young and mature leaves were affected. Closer examination of mature lesions revealed numerous brownish black acervuli that were produced in concentric rings, which is characteristic of anthracnose. The fungus was identified as Colletotrichum sansevieriae Nakamura based on typical cultural characteristics, conidial and appressoria morphology (1). Conidia were straight, cylindrical, obtuse at the apex, slightly acute at the base with a truncate attachment point, and 12.5 to 33 (18.4) × 4 to 8.9 (6.5) μm (n = 50). Hyphopodia were ovate, dark brown, single celled, and 6.2 to 8.7 (7.7) × 6.3 to 7.5 (7.3) μm (n = 25). Colonies on potato dextrose agar (PDA) were grayish white, felted with aerial mycelium, reverse gray to dark olivaceous gray, and partly cream in color. Sequences of the rDNA internal transcribed spacer (ITS) regions of two isolates (GenBank Accession Nos. JF911349 and JF911350) exhibited 99% nucleotide identity to an isolate of C. sansevieriae (GenBank Accession No. HQ433226) collected from diseased sansevieria in Australia. In addition, a maximum parsimony analysis (MEGA v.5.0) indicates that the two C. sansevieriae isolates from Florida are monophyletic (86% bootstrap support) with the type species from Japan (SA-1-2 AB212991; SA-1-1 AB212990) and the Australian isolate. Pathogenicity of our sequenced isolates was evaluated in greenhouse experiments. Twelve- to fourteen-week-old sansevieria plants were inoculated with conidial suspensions (1 × 106 conidia/ml) of C. sansevieriae. Inoculum or autoclaved water was sprayed over the foliage until runoff. Four plants of each of two economically important cultivars, Laurentii and Moonshine, were sprayed per treatment and the experiment was repeated twice. Inoculated plants were placed in a greenhouse at 29°C with 70 to 85% relative humidity. Plants were observed for disease development, which occurred within 10 days of inoculation for both cultivars. No symptoms developed on the control plants. Foliar lesions closely resembled those observed in the affected nurseries. C. sansevieriae was consistently reisolated from symptomatic tissue collected from greenhouse experiments. On the basis of molecular phylogenetics and distinguishing morphological characters, Nakamura et al. erected C. sansevieriae as a novel species that appears to be restricted to the host sansevieria (1). To our knowledge, this is the first report of C. sansevieriae causing anthracnose of sansevieria in Florida. Reference: (1) M. Nakamura et al. J. Gen. Plant Pathol. 72:253, 2006.

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First Report of Red-Fleshed Apple Anthracnose Caused by Colletotrichum siamense

Plant Disease ◽

10.1094/pdis-06-21-1132-pdn ◽

2021 ◽

Author(s):

Fengying Han ◽

Yu-tong Zhang ◽

Zaize Liu ◽

Lei Ge ◽

Lian-Dong Wang ◽

...

Keyword(s):

Sequence Data ◽

Phylogenetic Analyses ◽

Aerial Mycelium ◽

Morphological Characters ◽

Apple Fruit ◽

Bootstrap Support ◽

Single Spore ◽

First Report ◽

Crucial Information ◽

Average Size

The red-fleshed apple (Malus niedzwetzkyana) produces a colored fruit and rich anthocyanins and it has become popular among consumers in Shandong (Yang et al 2020). In recent years, anthracnose diseases have been reported in red-fleshed apple orchards and nurseries in Shandong province, China. The incidence of anthracnose in the red-fleshed apple plantings ranges from 50-90%. Initially, anthracnose lesions on fruit begin as sub-circular shaped, sunken, pale brown. Over time black lesions enlarged and coalesced into large necrotic areas. The sunken centers of mature lesion became filled with slimy pink sporulation. In September 2015, fifteen fruit with anthracnose symptoms and sporulation were collected, and 11 single-spore isolates were obtained. Three representative isolates (JNTW11, JNTW2, JNTW33) were used for morphological and molecular characterization. On PDA, the colonies were initially white and turned into pale brown in three days. Orange-brown pigmentation was produced near the center on the reverse. Aerial mycelium was cottony, dense, pale white to pale gray. Acervuli developed visible orange-pink conidial masses. Conidiophores were colorless, septate, not branched or branched at the base. Conidia were 1-celled, hyaline, subcylindrical, oblong, attenuated with blunt ends, and the average size was 16.7 ± 1.5 × 6.1 ± 0.9 μm (n = 50). Appressoria were brown, obovoid or irregular, 9.2 ± 1.6 × 8.0 ± 1.8 μm (n = 20). The morphological characters matched the descriptions of Colletotrichum gloeosporioides sensu lato (Cannon et al. 2008). Isolates JNTW11, JNTW2, and JNTW33 were subject to bioinformatic characterization by partial sequencing of 6 genetic loci including the ribosomal internal transcribed spacer (ITS), actin (ACT), beta-tub2 (TUB2), calmodulin (CAL), chitin synthase (CHS-1), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) (Weir et al, 2012). The ITS (MT577037, MT577040, MT577042), ACT (MT767712, MT767715, MT767717), TUB2 (MT767723, MT767726, MT767728), CAL (MT767689, MT767692, MT767694), CHS-1(MT767700, MT767703, MT767705), and GAPDH (MT767734, MT767737, MT767739) sequences were deposited in GenBank. The six sets of sequence data were concatenated “ITS-GAPDH-ACT-CHS-1-TUB2-CAL”, and the aligned sequences (2,007 bp) had 99.0% similarity to ex-type C. siamense ICMP18578. In a maximum likelihood phylogenetic tree, the highest log likelihood was -9148.55, and the isolates tested were in the C. siamense cluster with 96 % bootstrap support. Thus, the isolates were identified as C. siamense on the basis of multilocus phylogenetic analyses and morphological characters. To complete Koch’s postulates, several healthy red-fleshed apple fruit (‘Jiuhong’, 1 month prior to harvest) were inoculated using colonized and uncolonized hyphal plugs and a blank agar as a control. All inoculated fruit were placed in sterile tissue culture bottles containing 2 layers of wet paper towels at 28 °C under a 12 h light/dark cycle. All fruit developed anthracnose symptoms in 7 days while the controls did not develop any symptoms. The symptoms were similar to those collected from fruit in the field, and same fungus was re-isolated from the lesions. Presently it was known that C. acutatum, C. asianum, C. chrysophilum, C. cuscutae, C. fioriniae, C. fragariae, C. fructicola, C. gloeosporioides, C. godetiae, C. kahawae, C. karstii, C. limetticola, C. melonis, C. noveboracense, C. nymphaeae, C. paranaense, C. rhombiforme, C. salicis, and C. theobromicola could infect M. coronaria, M. domestica, M. prunifolia, M. pumila, and M. sylvestris worldwide. To our knowledge, this is the first report of C. siamense as a pathogen of M. niedzwetzkyana. This finding provides crucial information for the management of anthracnose disease in China.

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First Report of Anthracnose Caused by Colletotrichum navitas on Switchgrass in New York

Plant Disease ◽

10.1094/pdis-03-11-0164 ◽

2011 ◽

Vol 95 (8) ◽

pp. 1032-1032 ◽

Cited By ~ 2

Author(s):

K. D. Waxman ◽

G. C. Bergstrom

Keyword(s):

New York ◽

New Jersey ◽

Panicum Virgatum ◽

Molecular Phylogenetics ◽

Perennial Grass ◽

Leaf Tissue ◽

Morphological Characters ◽

Sensu Stricto ◽

First Report ◽

Greenhouse Experiments

Switchgrass (Panicum virgatum L.) is a perennial grass with significant potential as a biofuel crop. From 2007 to 2010, foliar lesions were observed in new and mature stands of switchgrass in various locations in New York. Lesions were elliptical with purple margins and white necrotic centers, generally <3 cm long, ~1 mm wide, often coalesced, and containing black setae. Upon incubation, symptomatic leaf tissue developed acervuli with masses of salmon-colored spores. The fungus was identified as Colletotrichum nativas Crouch on the basis of typical cultural characteristics and conidial morphology (1). Conidia were one-celled, hyaline, fusiform, and generally falcate. Conidial length averaged 40 μm (22 to 47 μm) and width averaged 5 μm (4 to 7 μm). Compared with other graminicolous species of Colletotrichum, the conidia were larger and varied from straight to irregularly bent. Sequences of the rDNA internal transcribed spacer (ITS) regions of three isolates (Cornell accession and corresponding GenBank Nos.: Cn071NY08 (from a >20-year-old naturalized stand of switchgrass in Steuben County), JF437053; Cn080NY08 (from ‘Pathfinder’ in Chemung County), JF437054; and Cn101NY09 (from ‘Blackwell’ in Chemung County), JF437055) exhibited 100% nucleotide identity to the type isolate of C. nativas (GenBank No. GQ919068) collected from switchgrass selection ‘Brooklyn’ in New Jersey (1). Pathogenicity of the sequenced isolates along with seven other isolates (Cn105NY09 from ‘Sunburst’ in Tompkins County; Cn107NY09 from ‘Trailblazer’ in Tompkins County; Cn109NY09 from ‘Forestburg’ in Tompkins County; Cn111NY09 and Cn112NY09 from ‘Shelter’ in Tompkins County; and Cn122NY09 and Cn123NY09 from ‘Cave-in-Rock’ in Genesee County) was evaluated in greenhouse experiments. Seven- to eight-week-old switchgrass plants were inoculated with conidial suspensions (1 × 106 conidia/ml) of C. nativas. Inoculum or sterilized water was sprayed until runoff. Three plants of each of ‘Cave-in-Rock’ and ‘Kanlow’ were sprayed per treatment and the experiment was repeated for 3 of the 10 isolates. Inoculated plants were placed in a mist chamber for 48 h before they were returned to the greenhouse and observed for disease development, which occurred within 1 week of inoculation for both cultivars. No symptoms developed on the control plants. Foliar lesions closely resembled those observed in the field. C. nativas was consistently reisolated from symptomatic tissue collected from greenhouse experiments. Switchgrass anthracnose associated with C. graminicola sensu lata has been reported in many U.S. states (2). On the basis of molecular phylogenetics and distinguishing morphological characters, Crouch et al. erected C. navitas as a novel species distinct from C. graminicola sensu stricto, a taxon restricted to the corn anthracnose pathogen (1). C. nativas was first documented on switchgrass in New Jersey (1) and appears to be the same pathogen causing anthracnose of switchgrass in the adjoining state of Pennsylvania (1,3). To our knowledge, this is the first report of C. nativas causing anthracnose of switchgrass in New York. References: (1) J. A. Crouch et al. Mycol. Res. 113:1411, 2009. (2) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , May 5, 2011. (3) M. A. Sanderson et al. Agron. J. 100:510, 2008.

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First Report of Pestalotiopsis guepini on Loquat in Argentina

Plant Disease ◽

10.1094/pdis.1999.83.7.695a ◽

1999 ◽

Vol 83 (7) ◽

pp. 695-695 ◽

Cited By ~ 1

Author(s):

A. E. Perelló ◽

S. Larran

Keyword(s):

Plant Disease ◽

Buenos Aires ◽

Aerial Mycelium ◽

Eriobotrya Japonica ◽

Conidial Suspension ◽

Diagnostic Laboratory ◽

Potato Dextrose Agar Medium ◽

First Report ◽

La Plata ◽

Symptomatic Tissue

Loquat, Eriobotrya japonica (Thunb.) Lindl., is used as an ornamental plant in home gardens in the La Plata area of Buenos Aires, Argentina. During spring 1998, loquat branches with spotted leaves and fruits were submitted to the Plant Disease Diagnostic Laboratory. Symptoms on leaves consisted of small (2 to 5 mm in diameter), circular to oblong, greenish brown lesions that expanded to amphigenous, isolated, or confluent, dark brown spots. On fruits the disease appeared as circular to elongated, sunken spots. Advancing lesions spread over the surface resulting in the death of the fruit. Acervuli were observed within lesions. Isolations from symptomatic tissue onto acidified potato dextrose agar medium consistently yielded white fungal colonies of sparse aerial mycelium with acervuli containing black, slimy spore masses. The fungus was initially identified as Pestalotiopsis guepini (Desmaz.) Steyaert based on conidial and cultural characteristics (1), and the identification was confirmed by Institute Spegazzini, La Plata, Buenos Aires, Argen-tina. Loquat branches with fruit and 3- to 6-month-old loquat plants were mechanically injured and sprayed with a conidial suspension of one of the P. guepini isolates (4.5 × 105 per ml). Plants were incubated in a moist chamber for 48 h and then maintained in a greenhouse. After 6 days, lesions similar to the original symptoms were observed on the inoculated plant and P. guepini was reisolated, confirming Koch's postulates. Control plants sprayed with distilled water remained symptomless. This is the first report of P. guepini causing leaf and fruit spots on loquat in Argentina. Reference: (1) J. B. H. J. Desmazières. Ann. Sci. Nat. Ser. 2. 13:181, 1840.

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First Report of Glomerella cingulata on Common Guava in Argentina

Plant Disease ◽

10.1094/pdis.2002.86.4.440b ◽

2002 ◽

Vol 86 (4) ◽

pp. 440-440

Author(s):

M. Carranza ◽

S. Larran ◽

B. Ronco

Keyword(s):

Colletotrichum Gloeosporioides ◽

Morphological Characteristics ◽

Aerial Mycelium ◽

Psidium Guajava ◽

Buenos Aires Province ◽

Glomerella Cingulata ◽

First Report ◽

Plastic Bags ◽

Untreated Individual ◽

Symptomatic Tissue

In Argentina, common guava (Psidium guajava L.) is frequently planted in gardens, but commercial production is limited. In February 2001, anthracnose symptoms were detected on fruits of common guava in La Plata, Buenos Aires Province. Symptoms of grayish, circular, sunken spots approximately 5 cm long were observed only on the surface of green unripe fruits. In humid conditions, acervuli containing salmon-pink masses of spores and dark setae were found within lesions. Symptomatic tissue was surface-disinfested, placed on potato dextrose agar, and incubated at 20°C. Cultures were obtained with abundant, gray, aerial mycelium and one-celled, hyaline, oblong, or cylindrical conidia with rounded ends (9.7 to 14.5 × 3.2 to 5.2 μm). Scarce dark brown perithecia developed in 2-month-old cultures but were not observed on fruit tissues. Asci were not conspicuous and contained straight or slightly curved ascospores (11.5 to 25.3 × 4 to 7 μm). The pathogen was identified as Glomerella cingulata (Stoneman) Spauld. & Schrenk (anamorph Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. in Penz), based on morphological characteristics (1,2). Ten healthy, immature, attached fruits of common guava were inoculated with 3 × 106 conidia per ml of each of six isolates of G. cingulata, and ten were left untreated. Individual fruits were enclosed in plastic bags and kept at 15 to 20°C. After 72 h, bags were removed, and after 20 days, anthracnose symptoms were observed only on inoculated fruits. G. cingulata was reisolated from fruit lesions, and Koch's postulates were fulfilled. To our knowledge, this is the first report of G. cingulata on common guava in Argentina. References: (1) B. C. Sutton. The Coelomycetes. CMI, Kew, England, 1980. (2) J. A. von Arx. Phytopathol. Z. 29:413, 1957.

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First report of Neopestalotiopsis protearum causing seed rot on Camellia oleifera in China

Plant Disease ◽

10.1094/pdis-12-20-2717-pdn ◽

2021 ◽

Author(s):

Jie Tang ◽

YiLin Du ◽

LiXiang Lai ◽

Qin Yang

Keyword(s):

Unsaturated Fatty Acids ◽

Aerial Mycelium ◽

Brown Rot ◽

Its Region ◽

Hunan Province ◽

Bootstrap Support ◽

Camellia Oleifera ◽

Single Spore ◽

First Report ◽

Seed Rot

Camellia oleifera, an evergreen small tree or shrub with high medicinal and ecological values, is mainly distributed in subtropical regions of China. Camellia oil obtained from Camellia oleifera seeds is rich in unsaturated fatty acids and unique flavors, and has become a rising high-quality edible vegetable oil in south of China (Zhuang 2008). The tea-oil tree Camellia oleifera plays important economic and ecological roles in Hunan province. During collecting trips, seeds of C. oleifera with disease symptoms have been observed in almost all oil-tea forests. In lab, the seeds can be infected by wounds and directly, however, wound infection is more rapid. In oil-tea forests, the wound of seed is often caused by external factors such as mechanical and insects. Symptomatic seeds exhibited brown rot symptoms with irregular, black spots, brown necrosis of the kernels, and accounted for 65% of the surveyed seeds (Fig. 1). Rotted seeds were surface-sterilized for 1 min in 75% ethanol, 3 min in 1% sodium hypochlorite, then rinsed for 2 min in sterile water and blotted on dry sterile filter paper. Discolored seed tissues were cut into pieces of 3 mm × 3 mm using a sterile scalpel, placed on potato dextrose agar (PDA) medium, and then incubated for 7 days at 25°C with a 12-h photoperiod. After 7 days of incubation, circular fungal colonies with dense aerial mycelium, produced black, wet spore masses. Four-septate conidia were ellipsoidal to obovoid, measuring 24 (22 to 26) × 6.5 (6 to 7) µm (n = 30). Conidia had three median cells, which were dark brown, with a single basal hyaline appendage, 4 (3.5 to 4.5) µm long, and two to four (usually three) apical hyaline appendages, 32 (27 to 35) µm long, similar to these recorded by Crous et al. (2011). Two single-spore isolates cultured on PDA medium were selected for DNA extraction. The ITS region was amplified using primers ITS5 and ITS4 (White et al. 1990). The partial translation elongation factor 1-alpha (tef1-α) gene region was amplified using primers EF1-728F (O'Donnell et al. 1998) and EF-2 (Carbone & Kohn 1999). The partial β-tubulin (tub2) was amplified using primers T1 and Bt2b (Glass & Donaldson 1995). The sequences of ITS (MW391815), tef1-α (MW398222), and tub2 (MW398223) were submitted to GenBank. BLAST analysis demonstrated that these sequences were 99%~100% similar to the sequences of ITS (MH553959), tef1-α (MH554377), and tub2 (MH554618) published for Neopestalotiopsis protearum. Phylogenetic analysis revealed that all the representative isolates recovered from symptomatic Camellia oleifera seeds showed 91% bootstrap support with Neopestalotiopsis protearum isolate in references (Fig. 2). Pathogenicity tests were conducted on 20 healthy seeds. We wounded the seeds by a sterilized needle on the middle position, and put the 5-mm-diameter agar plugs with actively grown mycelia (strain HNWC04) or pure PDA on the wound. We then covered the wounds with clean masking tape to prevent contamination and desiccation. After inoculation, the seeds were kept at 90 to 100% relative humidity at 25°C in a greenhouse for 3 weeks and monitored daily for lesion development. Twenty days after inoculation, all the seeds inoculated presented similar typical symptoms observed under natural conditions, whereas the control seeds showed no symptoms. Koch’s postulates were fulfilled by reisolating the same fungus and verifying its colony and morphological characters as Neopestalotiopsis protearum. To our knowledge, this is the first report of Neopestalotiopsis protearum causing oil-tea seed rot in China.

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First Report of Neofusicoccum parvum Associated with Chestnut Nut Rot in Italy

Plant Disease ◽

10.1094/pdis-01-21-0072-pdn ◽

2021 ◽

Author(s):

Salvatore Seddaiu ◽

Antonietta Mello ◽

Clizia Sechi ◽

Anna Cerboneschi ◽

Benedetto T. Linaldeddu

Keyword(s):

Elongation Factor ◽

Pcr Amplification ◽

Castanea Sativa ◽

Aerial Mycelium ◽

Mediterranean Area ◽

Morphological Characters ◽

Internal Transcribed Spacer Region ◽

Neofusicoccum Parvum ◽

First Report ◽

Sweet Chestnut

In autumn 2018, during a study on the pathogens involved in the etiology of chestnut nut rot symptoms observed in three of the main sweet chestnut (Castanea sativa) growing areas in Sardinia (Site 1: 39°56′55”N/09°11′45”E; site 2: 39°58’20”N/09°09′41”E; site 3: 40°52’50”N/09°08’45”E), Gnomoniopsis smithogilvyi was found to be the main causal agent. In addition to G. smithogilvyi, 15 out of 450 nuts processed, yielded on potato dextrose agar (PDA, 39 g/L) at 22°C white colonies with dense aerial mycelium becoming dark grey after 4 to 7 days. Pycnidia were produced within 4 weeks in half-strength PDA incubated at room temperature under natural daylight. The hyaline, ellipsoid to fusiform and aseptate conidia measured 13.4–19.2 × 4.8–7.7 μm (n = 50). All morphological characters matched those reported for Neofusicoccum parvum by Phillips et al. (2013). Identity of isolates was confirmed by DNA sequence analysis of the internal transcribed spacer region (ITS) and part of the translation elongation factor 1-alpha gene (tef1-α). DNA extraction, PCR ampliﬁcation reactions and DNA sequencing were carried out according to Linaldeddu et al. (2016). In the phylogenetic analysis based on combined ITS and tef1-α gene sequences the N. parvum isolates clustered within two well-supported subclades. In the first subclade (ML bootstrap = 88%) three isolates clustered together with the ex-type culture of N. parvum (CMW9081) while in the second subclade (ML bootstrap = 95%) three isolates clustered together with the ex-type culture of Neofusicoccum algeriense (CBS 137504), a species recently synonymised with N. parvum by Lopes et al. (2016). Sequences of six representative isolates were deposited in GenBank (MK968559–MK968564 and MT010339–MT010344 for ITS and tef1-α, respectively). The pathogenicity of six isolates, belonging to the two haplotypes, was undertaken by inoculating five asymptomatic nuts per isolate. After disinfecting the nut surface with 70% ethanol and removing a piece of shell (5 mm diameter) with a sterile cork borer, the nuts were inoculated with a same-sized agar-mycelium plug cut from the margin of a 5-day-old PDA colony. Ten control nuts were inoculated with a sterile PDA plug applied as described above. Inoculated nuts were kept in thermostat at 22 °C in the dark for 18 days. All nuts inoculated with N. parvum showed light-brown to dark necrosis of kernel associated with loss of tissue consistency. The symptoms were congruent with those observed in nature. All N. parvum isolates were successfully reisolated from all the inoculated nuts, fulfilling Koch’s postulates. No lesions were observed on controls. N. parvum is recognized as an emerging plant pathogen worldwide. In particular, several studies report N. parvum as a growing threat to agricultural and forest ecosystems in the Mediterranean area (Larignon et al., 2015; Manca et al., 2020). This is the first report of N. parvum causing chestnut nut rot in Italy.

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Monophyly of Heterandriini (Teleostei: Poeciliidae) revisited: a critical review of the data

Neotropical Ichthyology ◽

10.1590/s1679-62252012000100003 ◽

2012 ◽

Vol 10 (1) ◽

pp. 19-44 ◽

Cited By ~ 7

Author(s):

Alfy Morales-Cazan ◽

James S. Albert

Keyword(s):

Biological Sciences ◽

Morphological Characters ◽

Model Systems ◽

Morphological Data ◽

Maximum Parsimony Analysis ◽

Fin Ray ◽

Outgroup Species ◽

Tree Topologies ◽

Tree Resolution ◽

Shape Morphometrics

The systematics and taxonomy of poeciliid fishes (guppies and allies) remain poorly understood despite the relative importance of these species as model systems in the biological sciences. This study focuses on testing the monophyly of the nominal poeciliine tribe Heterandriini and the genus Heterandria, through examination of the morphological characters on which the current classification is based. These characters include aspects of body shape (morphometrics), scale and fin-ray counts (meristics), pigmentation, the cephalic laterosensory system, and osteological features of the neurocranium, oral jaws and suspensorium, branchial basket, pectoral girdle, and the gonopodium and its supports. A Maximum Parsimony analysis was conducted of 150 characters coded for 56 poeciliid and outgroup species, including 22 of 45 heterandriin species (from the accounted in Parenti & Rauchenberger, 1989), or seven of nine heterandriin species (from the accounted in Lucinda & Reis, 2005). Multistate characters were analyzed as both unordered and ordered, and iterative a posteriori weighting was used to improve tree resolution. Tree topologies obtained from these analyses support the monophyly of the Middle American species of "Heterandria," which based on available phylogenetic information, are herein reassigned to the genus Pseudoxiphophorus. None of the characters used in previous studies to characterize the nominal taxon Heterandriini are found to be unambiguously diagnostic. Some of these characters are shared with species in other poeciliid tribes, and others are reversed within the Heterandriini. These results support the hypothesis that Pseudoxiphophorus is monophyletic, and that this clade is not the closest relative of H. formosa (the type species) from southeastern North America. Available morphological data are not sufficient to assess the phylogenetic relationships of H. formosa with respect to other members of the Heterandriini. The results further suggest that most tribe-level taxa of the Poeciliinae are not monophyletic, and that further work remains to resolve the evolutionary relationships of this group.

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First Report of Pythium Root Rot of Rau Ram (Polygonum odoratum)

Plant Disease ◽

10.1094/pd-89-0340a ◽

2005 ◽

Vol 89 (3) ◽

pp. 340-340

Author(s):

E. N. Rosskopf ◽

C. B. Yandoc ◽

B. Stange ◽

E. M. Lamb ◽

D. J. Mitchell

Keyword(s):

Root Rot ◽

Vascular System ◽

Pond Water ◽

Centraalbureau Voor ◽

First Report ◽

Pathogenicity Tests ◽

Symptomatic Tissue ◽

Pythium Helicoides ◽

Production House ◽

Test Plants

Polygonum odoratum (= Persicaria odorata), known as rau ram or sang hum, is native to southeastern Asia and is a common herb in Vietnamese cuisine (1). It has been studied most extensively for its aromatic compound content (2). In Florida, rau ram commonly is grown hydroponically in greenhouses using large, cement beds with recirculated water. The plants form dense mats from which new growth is trimmed for market. During January of 2002, a severe dieback was observed in one production house in Saint Lucie County, FL. Plants with less severe symptoms were yellowed and stunted. Roots of symptomatic plants were largely decayed with root symptoms beginning as a tip necrosis. The cortex of severely affected roots slipped off easily, leaving a stringy vascular system. Plating of symptomatic tissue from 20 randomly selected plant samples was performed with multiple general and selective media including potato dextrose agar, corn meal agar with pimaricin, ampicillin, rifampicin, and pentachloronitrobenzene (PARP) (3). All colonies produced were identified as Pythium helicoides Drechsler on the basis of sporangial, oogonial, and antheridial characteristics (4). Isolates had proliferous, obovoid, papillate sporangia, and were homothallic with smooth-walled oogonia and thick-walled, aplerotic oospores. Multiple antheridial attachments per oogonium were common with the antheridium attached along its entire length. Pathogenicity tests were conducted using P. odoratum plants grown from commercial transplants. Two tests were performed. Each test was conducted using eight inoculated and eight control plants. In the first test, plants were maintained in 10-cm pots immersed in sterilized pond water for the duration of the test. Plants were inoculated with five 7- × 70-mm sections of freshly growing mycelial culture per plant using 10-day-old cultures of Pythium helicoides grown on water agar. Chlorosis was observed at approximately 2 months after inoculation. Root necrosis was observed in inoculated plants approximately 5 months after inoculation. This test was performed in the greenhouse with temperatures ranging from 20 to 30°C. The second test was performed in growth chambers at 35 to 40°C. Plants were maintained in 10-cm pots immersed in Hoagland's solution and were inoculated with four 6-mm plugs per plant. Symptoms were observed on inoculated plants at this temperature within 1 week of inoculation. No chlorosis or root decay was observed in noninoculated, immersed plants. The pathogen was reisolated from inoculated, symptomatic tissue. To our knowledge, this is the first report of root rot of P. odoratum caused by Pythium helicoides. References: (1) R. E. Bond. Herbarist 55:34, 1989. (2) N. X. Dung et al. J. Essent. Oil Res. 7:339, 1995. (3) M. E. Kannwischer and D. J. Mitchell. Phytopathology 68:1760, 1978. (4) A. J. van der Plaats-Niterink. Monograph of the Genus Pythium. Vol. 21, Studies in Mycology. Centraalbureau voor Schimmelcutltures, Baarn, The Netherlands, 1981.

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First record of roving coral grouper Plectropomus pessuliferus (Fowler, 1904) from Saint Martin’s Island, Bangladesh based on Morphology and DNA Barcoding

Bangladesh Journal of Fisheries ◽

10.52168/bjf.2020.32.34 ◽

2021 ◽

Vol 32 (2) ◽

pp. 293-301

Author(s):

MD JAYEDUL ISLAM ◽

SHARMIN AKTER ◽

PROVAKOR SARKAR ◽

MOHAMMAD RASHED ◽

IREEN PARVIN ◽

...

Keyword(s):

Dna Barcoding ◽

Bay Of Bengal ◽

New Record ◽

First Record ◽

Morphological Characters ◽

Marine Waters ◽

First Report ◽

Saint Martin ◽

Northern Bay Of Bengal

A new record of Plectropomus pessuliferus (Serranidae: Epinephelinae) wasdocumented based on morphological characters and DNA barcoding. The species was collectedduring a regular survey for making an inventory of reef associated fishes in Saint Martin`sIsland, Bangladesh. This is the first report of roving coral grouper from the marine waters ofBangladesh validated by morpho-meristic analysis and DNA barcoding. This is also the firstreport from the northern Bay of Bengal.

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First Report of Anthracnose of Papaya (Carica papaya L.) Caused by Colletotrichum siamense in China

Plant Disease ◽

10.1094/pdis-10-20-2154-pdn ◽

2021 ◽

Author(s):

Yujie Zhang ◽

Wenxiu Sun ◽

Ping Ning ◽

Tangxun Guo ◽

SuiPing Huang ◽

...

Keyword(s):

Carica Papaya ◽

Disease Incidence ◽

Aerial Mycelium ◽

Postharvest Disease ◽

Distilled Water ◽

First Report ◽

Surface Samples ◽

Initial Symptoms ◽

Colletotrichum Siamense ◽

Pathogenicity Tests

Papaya (Carica papaya L.) is a rosaceous plant widely grown in China, which is economically important. Anthracnose caused by Colletotrichum sp. is an important postharvest disease, which severely affects the quality of papaya fruits (Liu et al., 2019). During April 2020, some mature papaya fruits with typical anthracnose symptoms were observed in Fusui, Nanning, Guangxi, China with an average of 30% disease incidence (DI) and over 60% DI in some orchards. Initial symptoms of these papayas appeared as watery lesions, which turned dark brown, sunken, with a conidial mass appearing on the lesions under humid and warm conditions. The disease severity varied among fruits, with some showing tiny light brown spots, and some ripe fruits presenting brownish, rounded, necrotic and depressed lesions over part of their surface. Samples from two papaya plantations (107.54°E, 22.38°N) were collected, and brought to the laboratory. Symptomatic diseased tissues were cut into 5 × 5 mm pieces, surface sterilized with 2% (v/v) sodium hypochlorite for 1 minute, and rinsed three times with sterilized water. The pieces were then placed on potato dextrose agar (PDA). After incubation at 25°C in the dark for one week, colonies with uniform morphology were obtained. The aerial mycelium on PDA was white on top side, and concentric rings of salmon acervuli on the underside. A gelatinous layer of spores was observed on part of PDA plates after 7 days at 28°C. The conidia were elliptical, aseptate and hyaline (Zhang et al., 2020). The length and width of 60 conidia were measured for each of the two representative isolates, MG2-1 and MG3-1, and these averaged 13.10 × 5.11 μm and 14.45 × 5.95 μm. DNA was extracted from mycelia of these two isolates with the DNA secure Plant Kit (TIANGEN, Biotech, China). The internal transcribed spacer (ITS), partial actin (ACT), calmodulin (CAL), chitin synthase (CHS), β-tubulin 2 (TUB2) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) regions were amplified by PCR and sequenced. The sequences were deposited into GenBank with accessions MT904003, MT904004, and MT898650 to MT898659. BLASTN analyses against the GenBank database showed that they all had over 99% identity to the type strain of Colletotrichum siamense isolate ICMP 18642 (GenBank accession numbers JX010278, GQ856775, JX009709, GQ856730, JX010410, JX010019) (Weir et al., 2012). A phylogenetic tree based on the combined ITS, ACT, CAL, CHS, TUB2 and GAPDH sequences using the Neighbor-joining algorithm also showed that the isolates were C. siamense. Pathogenicity tests were conducted on 24 mature, healthy and surface-sterilized papaya fruits. On 12 papaya fruits, three well separated wounded sites were made for inoculation, and for each wounded site, six adjacent pinhole wounds were made in a 5-mm-diameter circular area using a sterilized needle. A 10 µl aliquot of 1 × 106 conidia/ml suspension of each of the isolates (MG2-1 and MG3-1) was inoculated into each wound. For each isolate, there were six replicate fruits. The control fruits were inoculated with sterile distilled water. The same inoculation was applied to 12 non-wound papaya fruits. Fruits were then placed in boxes which were first washed with 75% alcohol and lined with autoclaved filter paper moistened with sterilized distilled water to maintain high humidity. The boxes were then sealed and incubated at 28°C. After 10 days, all the inoculated fruits showed symptoms, while the fruits that were mock inoculated were without symptoms. Koch's postulates were fulfilled by re-isolation of C. siamense from diseased fruits. To our knowledge, this is the first report of C. siamense causing anthracnose of papaya in China. This finding will enable better control of anthracnose disease caused by C. siamense on papaya.

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