A fungal pathogen was isolated fromZoysiagrass leaf blight, so called‘inu-no-ashiato’, commonly infested in golf courses in Japan. From diagnostic studies, this fungus was considered nonspore forming type associated with genus Curvularia, grown with colored, septated thick wall mycelium looks as chlamydospores on PSA m edium. All of the culture experiments for inducing sporulatoin of the fungus has not succeeded. Ther efore, an identificatoin of this fungus was not achieved yet.
Isolations of the fungus were obtained frequently from diseased materials inZoysiagrass, but did rare from the healthy part. In inoculatoin tests of the isolates toZoysiagrass of pot grown sod or field turf, a typical leaf blight has appeared with similar symptoms of the disease‘inu-no-ashiato’in naturally infestedZoysiagrass. Two different species ofCurvularia, which are comfirmedC. geniculataandC. lunatarespectively, were found also in high frequency from both diseased and healthyZoysiagrass, but their pathogenicity was not confirmed clearly.

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We studied a correlation between the change of‘inu-no-ashiato’, a leaf blight ofZoysiagrasses, and the number of an isolated asporogenous fungus which could be associated with the disease occurrence in field. Patches of this disease were observed in test field Wakayama city area first in early June and early October. Maximum, average and minimum temperature of these month were 25-27°C, 21-33°C and 17-20°C respectively. There was considerable rainfall immediately before occurrence of the disease. The isolation frequency of asporogenous fungus was quite high with accordance of appearance observed. However, this fungus was hardly isolated from fields after the development of the disease reached its maximum.
Control effect of Procimidone fungicide to this disease was noted at a dose rate of 0.3 g/m² using 0.2 to 1/m²of water. A longer period was required in fall to reduce the disease by fungicides than in early summer, suggesting that earlier application of an effective fungicides could be necessary in fall to recover from the disease.

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In order to examine the definition and taxonomic status of Poa annua L. (1753) var. reptans H. C. Haussknecht (1891), the taxonomic literature of the world, references of weed and turf sciences, 176 sheets of herbarium specimens deposited in KYO, Graduate School of Science, Kyoto University and seven sheets of herbarium specimens collected at golf courses in Japan, are comprehensively investigated.
As a result, the protologue of Poa annua var. reptans described by Haussknecht (1891), is estimated a book taxon and his purpose of the description was to emphasize the prostrating of the variety. It is estimated that Magchev (1912) noted another example of this variety by drawing the typical two plants in Germany according to Haussknecht (1891) .
It is proper that the variety should be cited as Poa annua L. var. reptans Haussknecht sensu A. Magchev (1912) .

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Selective herbicidal activity of bispyribac sodium between cool-season turf grasses and annual bluegrass, and its inhibitory effect on heading and flowering of the weed were investigated in a glasshouse and/or fields.
Bispyribac sodium did not affect the growth of annual bluegrass applied at pre-emergence but showed excellent effectiveness when applied at post-emergence.
Annual type of annual bluegrass was more susceptible to bispyribac sodium than perennial type, and younger plants of both types were more susceptible than the older plants.
Bispyribac sodium showed good selectivity between four cool-season turf grasses (tall fescue, perennial ryegrass, bentgrass and Kentucky bluegrass) and annual bluegrass.
The degree of tolerance of the cool-season turf grasses to bispyribac sodium was in the order of perennial ryegrass ≥tall fescue>bentgrass>Kentucky bluegrass.
Bispyribac caused a transient chlorosis on the four cool-season turfgrasses at higher rates, however, the symptom disappeared within 25 days after the treatment. Selectivity of bispyribac sodium between the turfgrasses and annual bluegrass is larger in later application than in earlier application.
Bispyribac sodium strongly inhibited heading and flowering of annual bluegrass at the rate of 0.003 g a.i./m²for 4 weeks after the application in the fields as well.
These results suggest that bispyribac sodium can be used effectively tool for annual bluegrass control in cool-season turfgrasses.

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To investigate possibilities of the biological control against tuf grass insect pests by native predatory natural enemies, bionomics of ground beetles (Coleoptera: Carabidae) were studied at three golf courses in Shizuoka prefecture for two years and also some laboratory tests were carried out.
The field researches were carried out at three golf courses from June to October in 1997 and 1998. We investigated to make the species catalogue of the ground beetles and to examine the relation between seasonal population changes two lepidopteran pests of turf grass, Spodoptera depravata, Pediasia teterrellus and the ground beetles.
The results are as follows;
1) In our researches, there were many ground beetles in the golf courses. The number of species and population of the ground beetles were affected by the environmental factors and control strategy to the pests of each golf course.
2) However, in our field researches, we could not show the relationship between ground beetles and lepidopteran pests.
3) On the other hands, the predatoon test of the beetle against S. depravata in the laboratory conditions showed these beetles could predate the lepidopteran pests vigrously. From this result, ground beetles will be able to expect that they have a sufficient faculty to control lepidopteran turf grass pests in the field condition.

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