• Mycobiology
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• v.38 no.2
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• pp.113-117
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• 2010

Trichoderma strains were evaluated under field conditions to assay their efficacy in suppressing Alternaria fruit rot disease and promoting chili plant growth. The experiment was conducted at the Botanical Garden, Rajshahi University, Bangladesh from July 2006 to March 2007. Application of Trichoderma harzianum IMI 392432 significantly (p = 0.05) suppressed the disease compared to Alternaria tenuis (T2) treatment and improved both growth and yield. The treatment T4 (T. harzianum IMI-392432 + A. tenuis) was most effective in reducing disease percentage (72.27%) compared to A. tenuis (T1) treatment. The highest seed germination rate (85.56%) and the highest growth and yield (12.5 g/plant) was also recorded in the same treatment (T4), followed by T5 (T. harzianum IMI-392433 + A. tenuis), T6 (T. harzianum IMI-392434 + A. tenuis), T2 (T. virens IMI-392430 + A. tenuis), and T3 (T. pseudokoningii IMI-392431 + A. tenuis) treatment, while single treatment with A. tenuis significantly decreased these values.

• The Korean Journal of Mycology
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• v.6 no.1
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• pp.15-20
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• 1978

The purpose of the present study is to describe growth characteristics of seven species of Alternaria occur on naturally infected seeds, and to set up a guide line for quick identification of the species in connection with routine seed health testing. Host range and economic importance of each species are discussed and described with phototographs. The species studied are Alternaria tenuis, A. brassicicola, A. brassicae, A. raphani, A. dauci Alternaria radicina and A. sesami. Other resembling species are discussed in this paper.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.199-205
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• 1985

1. Alternaria tenuis, Cladosporium cladosporioides, Curvularia lunata Fusarium semitectum, Gerlachia oryzae, Phoma sp. Trichoconiella padwickii were found associated with ear blighting of rice plants. The frequency of isolation of the fungi was found to be higher from the severely discolored rice grains than that from the brownish spotted grains, but H. oryzae was encounted highly from the latter. 2. Higher counts of Alternaria tenuis, Helminthosporium oryzae, Trichoconiella padwickii, Fusarium moniliforme, Fusarium semitectum were observed under alternating cycles of 12hrs of light and darkness than under complete darkness but G. oryzae was encountered highly under darkness in the blotter. While no difference in the occurrence of the other fungi was recorded under l2hr NUV light-12hr darkness cycles and darkness. 3. A. tenuis and C. cladosporioides were encountered highly at the lower temp. $(15^{\circ}C)$ but Phoma sp. was occurred highly at the higher temp. $(30^{\circ}C)$ when the seeds were incubated in the blotter. 4. Artificial inoculation of the fungi in the ears of rice plants caused severe discoloration of rice grains and reduced 1,000 grain weights and grain ripening percentage.

• Korean journal of applied entomology
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• v.11 no.2
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• pp.101-107
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• 1972

This experiment was conducted in order to determine the fungi associated with ear blight of rice and their chemical control. 1, Pyricularia oryzes, Helminthosporium oryzne, Epicoccum purpurascens, Curvularia lunata, Cladosporium cladosporoides and Alternaria tenuis et al. were mainly detected in large quantities from the discolored seeds of recommended varieties but Trichoconis padwickii, Fusarium dimerum, and Nigrospora oryzae were mainly detected from Tongil. 2. Pyricularia oryzae, Nigrospora oryzae, and Curvularia lunate et at. were from the necks; Helminthosporium oryzae, Trichoconis padwickii, Stemphylium sp. , Cladosporium cladosporoides, and Alternaria tenuis et at. were from the branches of ear; and Phoma spp. was mainly detected from the kernels. 3. In the laboratory Difolatan WP $0.13\%$ gave good control of Helminthosporium oryzae, Cladosporium cladosporoides, and Alternaria tenuis, et al.; and Dithane M-45 WP $0.2\% gave especially good control of Pyricularia oryzae, Trichoconis padwickii, and Curvularia lunate. 4. In field experiments, the appropriate date of chemical spray was milk ripening stage or panicle emergence stage. Under these conditions Hinosan Ec and Kasugamin Ec were more effective than Difolatan WP and Dithane M-45 WP. However, the assessment of ear blight was complicated by a severe outbreak of neck blast.

• Korean Journal of Agricultural Science
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• v.6 no.1
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• pp.27-32
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• 1979

Seed samples of sesame (Sesamum indicum L.) from Chung-nam Provincial Office of Rural Development were infected by 12 fungi. Alternaria sesamicola, A. tenuis and Corynespora cassicola were the predominant fungi. Except C. cassicola, all fungi were almost completly reduced and wipid out the infections by pretreatment with chlorine. Plating of seed components also indicate that C. cassicola was well-established infections. In infection experiment C. cassicola produced severe leaf and stem spots and blights on sesame plants and showed severe seed and seedling rot.

• Korean journal of applied entomology
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• v.20 no.4 s.49
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• pp.183-190
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• 1981

Alternaria sesami, A. sesamicola, A. tenuis, A. longissima, Cercospora sesami, Cephalosporium sp., Corynespora cassiicola, Fusarium equiseti, F. moniliforme, F. oxysporum, F. semitectum, Macrophomina phaseolina and Myrothecium roridum were detected from 40 seed samples of sesame. A sesami, A. sesamicola, A. tenuis and C. cassiicola were the predominant fungi. Except C. cassiicola, all fungi were almost completly reduced and wiped out the infection by pretreatment with chlorine. Plating components also indicate that C. cassiicola was well-established infections. Seedborne infection of C. cussiicola caused heavy seed rot and seedling mortality. Detailed description has been given on the habit character of C. cassiicola under stereoscopic microscope and the variation in colony character and spore morphology have been taken into account. In inoculation experiments, C. cassiicola produced severe leaf and stem spots and blights on sesame plants resulted in ultimate death of the plants. A. sesami, A. sesamicola A. longissima and C. sesami also produced mild to severe leaf spotting and leaf blight when suspension of their conidia were sprayed on to plants. In soil inoculation experiments, F. oxysporum and M. phaseolina were the most pathogenic causing seed rot and seedling blight.

• The Korean Journal of Mycology
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• v.12 no.1
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• pp.27-33
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• 1984

Alternaria tenuis, Arthrobotrytis sp., Aspergillus spp., Cephalosporium sp., Cladosporium sp., Cylindrocarpon sp., Fusarium equiseti, F. moniliforme, F. semitectum, F. solani, Penicillium spp., Rhizopus sp. were saprophytic fungi and Cercospora kikuchii, Colletotrichum truncatum, Diaporthe phaseolorum var. sojae and Fusarium oxysporum were pathogenic fungi detected from 14 seed samples of soybean. Initial symptoms caused by C. kikuchii, C. truncatum, D. phaseolorum sojae and F. oxysporum on seedlings from naturally infected seed by the test tube agar method have been described and discussed. Soybean seeds infected with C. truncatum, D. phaseolorum sojae and F. oxysporum reduced germination of seeds and have influenced on the growth of soybean seedling caused by C. kikuchii. Surface-sterilized soybean seedlings became diseased in the test tube agar artificially inoculated with C. kikuchii, C. truncatum and D. phaseolorum sojae isolated from naturally infected soybean seeds. F. oxysporum showed very weak pathogenicity. Seed disinfectants of Benlate-T, Homai, Tecto and Sisthane have effective to C. kikuchii, C. truncatum, D. phaseolorum sojae and F. oxysporum. Arasan, Captan, Busan-30 and Mercron were inferior to C. kikuchii but effective against others. Seed disinfectants treated in this experiment have increased seed germination campared with non-treatment.

• Korean journal of applied entomology
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• v.25 no.2 s.67
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• pp.107-112
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• 1986

Species of pathogens and insects associated with grain discoloration in the Philippines were indentified. Leptocorisa oratorios was the most dominant insect species causing discoloration. Pathogenicity tests of fungal organisms isolated from discolored grains showed that Drechslera oryzae, Curvularia lunata, Trichoconiella padwickii, Sarocladium oryzae, Alternaria tenuis, and Fusarium solani were the common pathogens responsible for 'dirty panicle' disease of rice. Discoloration incidence was higher on treatment when both pests were present than when they occurred singly. The discoloration severity was attributed to the pathogens whereas rice bug caused a high decrease in grain weight and unfilled grains. Rice bug feeding on grains enhances the infection caused by the pathogen. Due to this, the quantity and quality of grains produced were affected, resulting in yield reduction.

• Mycobiology
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• v.34 no.3
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• pp.138-142
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• 2006

Soil cyanobacteria isolated from the rice paddy fields of 10 different locations across Korea were evaluated by agar plate diffusion test for antifungal activity. Aqueous, petroleum ether, and methanol extracts from one hundred and forty two cyanobacterial strains belonging to the 14 genera were examined for antifungal properties against seven phytopathogenic fungi causing diseases in hot pepper (Capsicum annuum L). Of total cyanobacteria, nine cyanobacteria (6.34%) exhibited antifungal effects. The nine cyanobacteria selected with positive antifungal activities were two species of Oscillatoria, two of Anabaena, three of Nostoc, one of Nodularia, and one of Calothrix. Alternaria alternata and Botrytis cinerea were inhibited by nine and eight species of cyanobacteria, respectively. Rhizopus stolonifer was suppressed by only methanol extract of Nostoc commune FK-103. In particular, Nostoc commune FK-103 and Oscillatoria tenuis FK-109 showed strong antifungal activities against Phytophthora capsici. Their antifungal activity at the late exponential growth phase is related to the growth temperature and not associated with the growth parameters such as cell biomass and $chlorophyll-{\alpha}$ concentration. The high inhibition levels of antibiotics were 22.5 and 31.8 mm for N. commune FK-103 and O. tenuis FK-109, respectively. The optimal temperature for antibiotic productivity was $35^{\circ}C$.

• Korean journal of applied entomology
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• v.18 no.3 s.40
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• pp.119-126
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• 1979

From the sample seeds of rice cultivar Palkoeng with the brown spot symptom, Helminthosporium oryzae was detected in $86\~92\%$ of hulls including empty glumes, lemma, palea, and rachilla in five to seven days of incubation. When the seeds were dehulled, the percentage detection decreased to $74\~83\%$ of pericarps. The fungus sporulated on whole surface of the seed and was detected within about ten cell layers deep of endosperm but not detected in embryo. Fusarium moniliforme was found in embryo as well as pericarp and endosperm. The frequency of F. roseum, Trichoconis padwickii, Curvularia spp., Atternaria tenuis, Cladosporium cladosporoides and Phoma sp. was less than three percent of hulls and pericarps. In seven days of incubation, $60\~87\%$ of the germinating seeds showed the symptom of H. oryzae while $13\~40\%$ were apparently healthy. This fungus in hilum of infected rice transmitted through pericarp to plumule shoot and radicle of the germinating seed.