First Report of Geotrichum candidum as a Pathogen of Sweetpotato Storage Roots from Flooded Fields in North Carolina and Louisiana

In October 1997, samples of diseased sweetpotato (Ipomoea batatas (L.) Lam.) roots from storage were submitted for diagnosis to the Plant Disease and Insect Clinic at North Carolina State University. Two organisms were detected from soft rotted roots: Rhizopus stolonifer (Ehrenb.:Fr.) Vuill. (cause...

Ausführliche Beschreibung

Bibliographische Detailangaben
Veröffentlicht in:Plant disease. - 1997. - 86(2002), 6 vom: 01. Juni, Seite 695
1. Verfasser: Holmes, G J (VerfasserIn)
Weitere Verfasser: Clark, C A
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2002
Zugriff auf das übergeordnete Werk:Plant disease
Schlagworte:Journal Article
LEADER 01000naa a22002652 4500
001 NLM294475826
003 DE-627
005 20231225081548.0
007 cr uuu---uuuuu
008 231225s2002 xx |||||o 00| ||eng c
024 7 |a 10.1094/PDIS.2002.86.6.695C  |2 doi 
028 5 2 |a pubmed24n0981.xml 
035 |a (DE-627)NLM294475826 
035 |a (NLM)30823259 
040 |a DE-627  |b ger  |c DE-627  |e rakwb 
041 |a eng 
100 1 |a Holmes, G J  |e verfasserin  |4 aut 
245 1 0 |a First Report of Geotrichum candidum as a Pathogen of Sweetpotato Storage Roots from Flooded Fields in North Carolina and Louisiana 
264 1 |c 2002 
336 |a Text  |b txt  |2 rdacontent 
337 |a ƒaComputermedien  |b c  |2 rdamedia 
338 |a ƒa Online-Ressource  |b cr  |2 rdacarrier 
500 |a Date Revised 20.11.2019 
500 |a published: Print 
500 |a Citation Status PubMed-not-MEDLINE 
520 |a In October 1997, samples of diseased sweetpotato (Ipomoea batatas (L.) Lam.) roots from storage were submitted for diagnosis to the Plant Disease and Insect Clinic at North Carolina State University. Two organisms were detected from soft rotted roots: Rhizopus stolonifer (Ehrenb.:Fr.) Vuill. (cause of Rhizopus soft rot) and Geotrichum candidum Link. Attempts to duplicate a soft rot by stab-inoculation of sweetpotato roots with a pure culture of G. candidum were unsuccessful. In Louisiana, following heavy rains due to Tropical Storm Frances in 1998, sweetpotato roots exhibiting a cortical tissue collapse at time of harvest were submitted to Louisiana State University for disease identification. Isolations from lesion margins consistently yielded G. candidum. Attempts to reproduce the disease by stab-inoculation produced only a few restricted lesions 5 to 15 mm in diameter. In 1999, rains from hurricanes Dennis, Floyd, and Irene caused extensive flooding in sweetpotato-growing areas of the North Carolina Coastal Plain. Extensive losses occurred in many fields due to a condition known as "souring," and G. candidum was frequently detected sporulating on the surface of soured roots. This provided a clue for reproducing the disease artificially (1). In 2000, the disease was successfully reproduced. Sterile, wood toothpicks were dragged across a pure culture of G. candidum and inserted (1.5 cm deep) into the mid-section of sweetpotato (cv. Beauregard) roots. Roots were submerged in water at room temperature (23°C) for 24 to 48 h. Each of four roots was inoculated four times, and sterile toothpicks were stabbed into the controls. Additional controls consisted of an inoculated root that was not submerged in water, and a root that was not wounded or inoculated but submerged in water. Following submersion, roots were incubated at room temperature for 5 days. The experiment was repeated. Isolations from diseased tissues consistently yielded G. candidum. Symptoms consisted of slightly sunken, circular lesions, typically 15 to 50 mm in diameter. In cross-section, diseased tissue surrounding the wound was darkened, soft (but not watery), and extended 1 to 20 mm on either side of the wound. None of the controls showed signs of decay. These symptoms are consistent with but do not represent the full range of symptoms observed in the field. Souring of sweetpotato is likely the result of a complex of factors including predisposition of roots by water-saturated soil and the pathogenic effects of G. candidum. To our knowledge, this is the first known report of rot caused by G. candidum on sweetpotato in the United States. G. candidum was reported on sweetpotato in India, but no pathogenicity tests were reported (2). References: (1) E. Cohen and J. W. Eckert. Plant Dis. 75:166, 1991. (2) N. C. Mandal and M. K. Dasgupta. Indian J. Mycol. Plant Pathol. 10:31, 1980 
650 4 |a Journal Article 
700 1 |a Clark, C A  |e verfasserin  |4 aut 
773 0 8 |i Enthalten in  |t Plant disease  |d 1997  |g 86(2002), 6 vom: 01. Juni, Seite 695  |w (DE-627)NLM098181742  |x 0191-2917  |7 nnns 
773 1 8 |g volume:86  |g year:2002  |g number:6  |g day:01  |g month:06  |g pages:695 
856 4 0 |u http://dx.doi.org/10.1094/PDIS.2002.86.6.695C  |3 Volltext 
912 |a GBV_USEFLAG_A 
912 |a SYSFLAG_A 
912 |a GBV_NLM 
912 |a GBV_ILN_350 
951 |a AR 
952 |d 86  |j 2002  |e 6  |b 01  |c 06  |h 695