Characterization of Ribbed Mussel Geukensia demissa (Dillwyn, 1817) Habitat in Relation to Tidal Elevation and Salinity in a South Carolina Estuary

A long-term time series of high-frequency sampled sea-level data collected in the port of Genoa were analyzed to detect the occurrence of meteotsunami events and to characterize them. Time-frequency analysis showed well-developed energy peaks on a 26–30 minute band, which are an almost permanent feature in the analyzed signal. The amplitude of these waves is generally few centimeters but, in some cases, they can reach values comparable or even greater than the local tidal elevation. In the perspective of sea-level rise, their assessment can be relevant for sound coastal work planning and port management. Events having the highest energy were selected for detailed analysis and the main features were identified and characterized by means of wavelet transform. The most important one occurred on 14 October 2016, when the oscillations, generated by an abrupt jump in the atmospheric pressure, achieved a maximum wave height of 50 cm and lasted for about three hours.

Download Full-text

Characterization of Pythium Species Collected from a Multiple Time-Point Sampling of Cucurbits in South Carolina

Plant Disease ◽

10.1094/pdis-04-20-0728-re ◽

2020 ◽

Vol 104 (11) ◽

pp. 2832-2842

Author(s):

Sean M. Toporek ◽

Anthony P. Keinath

Keyword(s):

South Carolina ◽

The United States ◽

Common Species ◽

Multiple Time ◽

Pythium Species ◽

Multiple Time Point ◽

Mitochondrial Cytochrome Oxidase ◽

Time Point

Species of Pythium cause root and stem rot in cucurbits, but no formal surveys have been conducted in the United States to identify which species are responsible. The cucurbit hosts bottle gourd, cucumber, Hubbard squash, and watermelon were transplanted in May, July, September, and November into sentinel plots in four and five different fields in 2017 and 2018, respectively, in South Carolina. Eight of the nine fields were replanted in March 2019. Isolates (600) were collected and identified by sequencing DNA of the mitochondrial cytochrome oxidase I region. The four most common species were P. spinosum (45.6% of all isolates), P. myriotylum (20.0%), P. irregulare (15.3%), and P. aphanidermatum (12.8%). P. myriotylum and P. aphanidermatum were predominantly isolated in May, July, and September, whereas P. spinosum and P. irregulare were predominantly isolated in November and March. Isolates of P. ultimum, P. irregulare, and P. spinosum were more virulent than isolates of P. myriotylum and P. aphanidermatum at 25°C. Representative isolates were screened in vitro for sensitivity to three fungicides: mefenoxam, propamocarb, and oxathiapiprolin. All isolates were sensitive to mefenoxam and propamocarb, but these same isolates were insensitive to oxathiapiprolin, except those classified taxonomically in Pythium clade I.

Download Full-text

Digestive physiology of the ribbed mussel Geukensia demissa (Dillwyn) held at different tidal heights

Journal of Experimental Marine Biology and Ecology ◽

10.1016/s0022-0981(96)02694-9 ◽

1997 ◽

Vol 209 (1-2) ◽

pp. 201-213 ◽

Cited By ~ 25

Author(s):

Francois Charles ◽

Roger I.E. Newell

Keyword(s):

Digestive Physiology ◽

Geukensia Demissa ◽

Ribbed Mussel

Download Full-text

Characterization of Leaf Spot Pathogens from Several Spinach Production Areas in the United States

Plant Disease ◽

10.1094/pdis-11-19-2450-re ◽

2020 ◽

Vol 104 (7) ◽

pp. 1994-2004

Author(s):

Bo Liu ◽

Larry Stein ◽

Kimberly Cochran ◽

Lindsey J. du Toit ◽

Chunda Feng ◽

...

Keyword(s):

United States ◽

South Carolina ◽

Leaf Spot ◽

The United States ◽

Leaf Damage ◽

Leaf Spots ◽

Pathogenicity Tests ◽

Agar Media ◽

Production Areas

Leaf spot diseases have become a major concern in spinach production in the United States. Determining the causal agents of leaf spots on spinach, their prevalence and pathogenicity, and fungicide efficacy against these pathogens is vital for effective disease management. Spinach leaves with leaf spots were collected from Texas, California, Arizona, and South Carolina from 2016 to 2018, incubated in a moist chamber, and plated on potato dextrose and tryptic soy agar media. Fungal and bacterial colonies recovered were identified based on morphology and sequence analysis of the internal transcribed spacer rDNA and 16S rRNA, respectively. Two predominant genera were isolated: (i) Colletotrichum spp., which were identified to species based on sequences of both introns of the glutamate synthetase (GS-I) and glyceraldehyde-3-phosphate dehydrogenase (gapdh-I) genes; and (ii) Stemphylium spp., identified to species based on sequences of the gapdh and calmodulin (cmdA) genes. Anthracnose (Colletotrichum spinaciae) and Stemphylium leaf spot (Stemphylium vesicarium and S. beticola) were the predominant diseases. Additional fungi recovered at very limited frequencies that were also pathogenic to spinach included Colletotrichum coccodes, C. truncatum, Cercospora beticola, and Myrothecium verrucaria. All of the bacterial isolates were not pathogenic on spinach. Pathogenicity tests showed that C. spinaciae, S. vesicarium, and S. beticola caused significant leaf damage. The fungicides Bravo WeatherStik (chlorothalonil), Dithane F-45 (mancozeb), Cabrio (pyraclostrobin), and Merivon (fluxapyroxad and pyraclostrobin) were highly effective at reducing leaf spot severity caused by an isolate of each of C. spinaciae and S. vesicarium, when inoculated individually and in combination.

Download Full-text