• The Korean Journal of Mycology
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• v.37 no.2
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• pp.121-129
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• 2009

In 2007, a total of 77 isolates of Fusarium spp. were obtained from ear rot symptoms of corns collected from 5 locations in Gangwon Province, Korea. The fungal isolates were identified based on their morphological features. Out of the isolates, fifteen isolates were identified as Fusarium verticillioides which formed microconidia in long chains on monophialides. Four isolates were identified as F. subglutinans which formed microconida only on false heads. Six isolates were identified as F. graminearum which produced red pigment in PDA culture. Besides these Fusarium species, F. napiform, F. nygamai, and F. oxysporum were identified from the rest isolates. To assess for genetic diversity of the isolates, a random amplified polymorphic DNA(RAPD) technique was carried out using URP primers. The results from the RAPD analysis showed that the isolates from corn were divided into 6 groups. These RAPD groups of the Fusarium species corresponded to morphological characters of the Fusarium species. The phylogenetic analysis of most isolates by DNA sequencing of EF-1$\alpha$ gene corresponded to morphological characters of the Fusarium species. The results of pathogenicity tests by two inoculation methods revealed that F. verticillioides, F. graminearum and F. subglutinans are strongly pathogenic to corn stalks.

• Research in Plant Disease
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• v.17 no.3
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• pp.369-375
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• 2011

Fusarium verticillioides (teleomorph: Gibberella moniliformis), a member of the Gibberellea fujikuroi species complex, causes rots of corn stalks and ears, and produces a group of mycotoxins known as fumonisins that are harmful to animals and humans. Here, we focus on the development of a species-specific PCR primer set for differentiating F. verticillioides from other fumonisin-producing Fusarium species belonging to the species complex, such as F. proliferatum, F. fujikuroi, and F. subglutinans that are frequently associated with corn. The specific primers (RVERT1 and RVERT2) derived from the nucleotide sequences of RNA polymerase II beta subunit (RPB2) gene amplified a 208 bp-DNA fragment from only F. verticillioides isolates among the potential fumonisin-producing species examined; all of these isolates were shown to carry FUM1 required for fumonisin biosynthesis. The PCR detection limit using this specific primer set was approximately 0.125 pg/${\mu}l$ genomic DNA of F. verticillioides. In addition, the F. verticillioides-specfic fragment was successfully amplified from genomic DNAs of corn samples contaminated with Fusarium spp. This primer set would provide a useful tool for the detection and differentiation of potential fumonisin-producing F. verticillioides strains in cereal samples.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.5 no.1
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• pp.57-64
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• 1969

Several field and sweet corn varietiea from several sources were crossed with a variety carrying the opaque-2 gene to determine the phenotypic interactions in the breeding of high lysine maize. Although opaque-2 lines showed lower protein content than the corresponding normal varieties, there was no correlation between the protein levels of the two types. opaque-2 maize contained more lysine, but no relationship was found between the protein content and the lysine content of either normal or opaque-2 types, suggesting that high lysine corn using the opaque-2 gene may be developed independently from the protein content. The F2 segregation ratios for normal and opaque-2, 100-kernel weights, percentage seed set, opaque-2 phenotype, disease susceptibility, and the relationship between protein and lysine content of normal and opaque-2 were investigated. The determinations and observations were made on the F2, F3, and BC1 Lysine content was determined by the ion exchangeresin combined with paper chromatography method. Most crosses segregated in a 1-opaque-2 : 3-normal ratio as expected. Opaque-2 segregates were lighter than the normal type and smaller in size. A mottled phenotype of opaque-2 maize observed in the Philippines yellow endersperm. In some varieties opaque-2 maize was very susceptible to the ear and kernel rot disease. No. 5(female) and opaque-2(male). Selectlon of a double mutant of waxy and opaque-2 by using the iodine technique and electric lamp was discussed. opaque-2 and floruy-2 were not allels. Different percentage of seed set were observed in the segregation of aewx crossed with opaque-2. An unusual gametophytie relationship was involved in a cross between Glutinous.