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Fungal disease occurring from summer to autumn and causing large damage in the warm regions. It occurs in the leaf, stalk and petiole and produces yellowish brown, spindle shaped lesions sinking a little with black mold (setae) in the center part. The upper part of the lesion often withers and the entire plant is killed in results when occurring severely. The causal organism can infect alfalfa, too. |
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Fungal disease which produces spots in the leaf. The lesions at first appear as yellow discolored parts, and soon they turn to brown and become characteristic V letterform lesions devided by the leaf vein. When the petiole is infected, the leaf withers and are killed soon. When occurring severely, the whole plant looks like burned and the yield decreases much. Damage is large in younger leaves than old ones. It occurs severely when the temperature increases considerably after the rainy season. The pathogen infects other clovers. |
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Fungal disease which makes plants white powdery. White, thin and indistinct colonies like sprinkled white powder are produced on the surface of the leaf in the early spring. They gradually become thick, cover the whole leaf and cause leaf blight. The disease occurs severely in the cool and dry condition, and the damage becomes large when sunshine is insufficient under the cloudy weather. The damage is not so large not like in red clover. The causal organism can infect other legumes. |
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Spot-causing fungal disease mainly occurring in the leaf and stalk. The lesions are grayish brown devided by leaf veins, fuse mutually and cause leaf blight. They become purple brown stripes when occurring in the stalk and the damage enlarges. The causal organism can infect other kinds of clovers, but the pathogenicity is considered to be differentiated. |
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Important fungal disease which occurs all over the country and becomes a cause of summer depression of grassland. Ash green and water-soaked lesions appears at first and the whole infected plant soften like being boiled before long. Then, the infected stalks and leaves fall one upon another and rot when the disease progresses and hyphae like spider' web appear covering all the infected part. Later light brown to brown sclerotia of about 5 mm in diameter are produced on the infected part. At this point, the infected grass withers forming patches and the grassland gradually becomes bare land. The causal organism is polyxeny and can infect most grasses and legumes of herbage. |
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Fungal disease occurring in the entire upper-ground part. The lesions are blackish brown and irregular shaped ones in the leaf. They soon fuse mutually and become large lesion which covers the whole leaf. The black and fluffy sclerotia are produced in the center part of the lesion. Black hyphae extends to the entire plant when occurring severely and cause plant death. The causal organism produces the alkaloid, suraflamine, which causes goat's slaver disease. |
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Spot-causing fungal disease occurring in the cool regions. The blackish brown, small lesions of about 1 mm in diameter are produced a lot and the whole leaf looks like sprinkled with black pepper. The surroundings of the lesion turn to yellow gradually and the leaf withers finally. It occurs severely in the cool condition with frequent rain. Black small grains (perithecia) are formed on the old lesions. The species of the causal organism is different from pepper spot fungus of alfalfa. |
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Spot-causing fungal disease occurring in the cool regions. The blackish brown, small lesions of about 1 mm in diameter are produced a lot and the whole leaf looks like sprinkled with black pepper. The surroundings of the lesion turn to yellow gradually and the leaf withers finally. It occurs severely in the cool condition with frequent rain. Black small grains (perithecia) are formed on the old lesions. The species of the causal organism is different from pepper spot fungus of alfalfa. |
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Important fungal disease which causes plant death occurring in cool and wet regions. The small spots appears at first and then the leaf and stalk turn to yellow and wither. The disease progresses gradually under the snowfall. The stem, leaf and root rot to ash white according to increase of the temperature after snow-melting in the spring of next year. White and fluffy hyphae are produced on the surface of the withering plant and large black sclerotia of irregular types and about 8-10mm in size are produced before long. They germinate in autumn and produce light brown stroma of 3-8 mm in diameter. The ascospores spread from the stroma and the infection happens again. The host range of the causal organism is wide including alfalfa and vetches. |
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