+ Site Statistics
References:
54,258,434
Abstracts:
29,560,870
PMIDs:
28,072,757
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

First Report of Neocosmospora vasinfecta var. vasinfecta Causing Soybean Stem Rot in South Korea



First Report of Neocosmospora vasinfecta var. vasinfecta Causing Soybean Stem Rot in South Korea



Plant Disease 98(12): 1744



In September 2010, stem rot symptoms were observed on soybean plants (cv. Daepungkong) growing in a field located at Daegu (35.52° N, 128.35° E), South Korea. The first noticeable symptoms, observed on the top leaves, were difficult to distinguish from those of sudden death syndrome (SDS). However, after splitting the stems of symptomatic plants, typical stem rot symptoms appeared as reddish-brown to dark-brown discoloration of the pith. Stem lesions extended 15 to 20 cm upward from the soil surface. To isolate the causal agent, sections of diseased stems were surface disinfected with 1% sodium hypochlorite, placed on potato dextrose agar (PDA) containing streptomycin sulfate, and incubated at 25°C with a 12-h light regime. Two isolates were obtained (SSLNV17 and SSLNV18). Mycelia were white and floccose. Conidia (4.5 to 11.2 × 2.2 to 3.4 μm) were cylindrical to oblong-ellipsoidal, hyaline, and one-celled. Both isolates produced abundant perithecia after 3 to 4 weeks. Perithecia (205 to 331 mm in diameter) were orange to red, globose and ostiolate, with a short neck (80 to 126 mm in diameter). Unitunicate asci (88.6 to 115.3 × 14.5 to 17.3 mm) were cylindrical to clavate, with a short stalk (6.0 to 9.5 × 5.0 to 6.8 mm), and eight spores. Ascospores (13.3 to 17.5 × 10.7 to 12.7 mm) were uniseriately arranged, globose to oval, one-celled, and hyaline to pale brown, with walls with a rugose ornamentation. These morphological features are consistent with those of Neocosmospora vasinfecta var. vasinfecta (1). The internal transcribed spacer (ITS) region, partial translation elongation factor 1-alpha (EF1-α), and β-tubulin genes of rDNA of the two isolates were sequenced using primers ITS4/ITS5 (GenBank Accession Nos. KF662732 and KF662733), EF1-728F/EF1-986R (KF758839 and KF758840), and Bt2a/Bt2b (KF771004 and KF771005), respectively. Sequences of the ITS region, EF1-α, and β-tubulin genes of both isolates showed 99% similarity with several reported N. vasinfecta strains by BLAST analysis. Both morphological and sequence analyses confirmed that the two isolates were N. vasinfecta var. vasinfecta. Pathogenicity tests of both isolates were performed on 15 three-week-old seedlings of soybean cv. Williams inoculated with a spore suspension containing 1.0 × 106 spores/ml, using stem puncture inoculation procedure under controlled conditions (4). Control plants were inoculated in the same way with sterile water. The results were observed by splitting the stem longitudinally and checking for discoloration of the pith 4 to 5 weeks after inoculation. Reddish-brown to dark-brown discoloration was observed in the stem pith of inoculated plants, with occasional chlorosis of the leaves. Moreover, numerous orange-red perithecia were produced on the inoculated stems. However, no symptoms were visible on control plants. The pathogen was re-isolated from the diseased plants, confirming Koch's postulates. Neocosmospora stem rot of soybean was first discovered in Japan and since then it has been reported in the United States and China (2,3,4). To our knowledge, this is the first record of soybean stem rot caused by N. vasinfecta var. vasinfecta in Korea. Our report indicates that Neocosmospora stem rot is a new threat to soybean production in Korea. References: (1) P. F. Cannon and D. L. Hawksworth. Trans. Br. Mycol. Soc. 82:673, 1984. (2) Y. Gai et al. Plant Dis. 95:1031, 2011. (3) F. A. Gray et al. Plant Dis. 64:321, 1980. (4) D. V. Phillips. Phytopathology 62:612, 1972.

Please choose payment method:






(PDF emailed within 1 workday: $29.90)

Accession: 066446042

Download citation: RISBibTeXText

PMID: 30703896


Related references

First Report of Soybean Neocosmospora Stem Rot Caused by Neocosmospora vasinfecta var. vasinfecta in China. Plant Disease 95(8): 1031, 2019

Neocosmospora vasinfecta E.F. Sm. var. vasinfecta incitant of wilt in guara - a new host record from India. Plant Disease Research 6(2): 143, 1991

A novel saponin hydrolase from Neocosmospora vasinfecta var. vasinfecta. Applied and Environmental Microbiology 70(2): 865-872, 2004

A disease of Soybean caused by Neocosmospora vasinfecta. Phytopathology. 61: 8, 906, 1971

A soybean disease caused by Neocosmospora vasinfecta. Phytopathology 62(6): 612-615, 1972

Virulence and Genetic Variability of Neocosmospora Vasinfecta Causing ROOT ROT IN CHICKPEA. Journal of Plant Pathology 97(1): 209-209, 2015

Neocosmospora vasinfecta stem rot of soybeans glycine max in alabama usa. Plant Disease 64(3): 321-322, 1980

Neocosmospora vasinfecta pathogenic to groundnuts arachis hypogaea in south africa. Phytophylactica 17(1): 49-50, 1985

The morphology and organogenesis of Neocosmospora vasinfecta E. F. Smith and Neocosmospora africana von Axx. Ann. Sci. not., Bot, 17: 25, 353-370, 1956

Production of phyto toxins by neocosmospora vasinfecta and neocosmospora africana. Phytopathologische Zeitschrift 72(4): 327-334, 1971

First Report of Peanut Pod Rot Caused by Neocosmospora vasinfecta in Northern China. Plant Disease 96(3): 455, 2019

First report of peanut foot rot caused by Neocosmospora vasinfecta in mainland China. Plant Pathology 59(6): 1172-1172, 2010

Leg tumefaction with Neocosmospora vasinfecta in a renal transplant patient: First human case report. Journal de Mycologie Medicale 3(3): 165-168, 1993

First Report of Peanut Foot Rot Caused by Neocosmospora vasinfecta var. africana in Jiangxi Province, China. Plant Disease 95(11): 1480, 2019

Effect of soil temperature and moisture on survival of the soybean root rot fungi neocosmospora vasinfecta and fusarium solani in soil. Plant Disease Reporter 62(11): 945-949, 1978