Experiments were conducted to obtain same informations on the effect of under-drain materials on surface-drained water and herbicide run-off losses under rainfall simulations using test-yard ofZoysia japonica turf during 1993 to 1994. Treated plots were; conventional underdrain with drainpipe and masa soil (A), underdrain with drainsheet and masa soil (B), and underdrain with drainsheet and sand (C) . The herbicides used were; simazine, isoxaben, mecoprop, and asulam. The results were as follows;
1. Irrigation was simulated with 40-47mm/h. At plots C, surface water appeared slowly with less amount and disappeared faster as compared to other two plots
2. At the plots, B and C, underdrained water ranoff quickly in larger amount after irrigation, followed by quick decrease, while at plot A, water drained slowly with less amount of underdrained water.
3. The groundwater disappeared quickly in plot C, while in plot A the water disappeared very slowly, taking four times as long as the former. The groundwater of surface layer in plot A disappeared very slowly.
4. There were not much differences between the three plots in relation to the distribution of root weight at successive soil strata in 1994. But less amount of rhizomes were measured at surface layer in plot C as compared to the other.
5. Herbicide run-offs was examined in plots, A and C. Concentrations of simazine and isoxaben decreased more quickly in early under-drained water than surface-drained water in both plots. This tendency was clearer in plot C. The concentrations of mecoprop and asulam in underdrained water did not change much as compared to that of surface-drained water in both plots.

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A simple method for estimatingAcremoniumendophyte (EP) infestation levels of perennial ryegrass (Lolium perenne, PR) seed lots was developed. To blot the PR seed sap onto nitrocellulose membranes (NCM), the seed were allowed to imbibe water for two days and pressed on NCM with a vise (Vise blotting ELISA procedure (VBE) ) . EP infestation levels of the seeds using the VBE were almost equal to the levels of the microscopic staining method. The antigen of EP, which was adhered to NCM by VBE, could be stored for 3 months in a desiccator and could be mailed without reduction of the reaction color intensity. The feeding damage among 27 cultivar by bluegrass webworm (Pediasia teterrellus) varied inversely with endophyte infestation levels using the VBE and there was a distinct negative correlation between them (r=-0.94) . Therefore, we believe that endophyte infestation levels using VBE will indicate resistance to feeding damage by bluegrass webworm.

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Experiments were conducted to determine the allelopathic potential of manilagrass. Aqueous extract of the dried shoot tissue (50 mg/ml) showed stronger inhibitory effect on seed germination and seedling growth of radish (Raphanus sativus), goosegrass (Eleusine indica), rice (Oryza sativa), tomato (Lycopersicon eculentum) and other plants than that of the fresh shoot tissue. In general, extracts of the shoots were more inhibitory than those of roots and seeds. At lower concentrations, however, the shoot extract promoted germination and growth of livid amaranth (Amaranthus viridus) . Germination of these assay plants was reduced to a greater extent as compared to seedling growth by these extracts. When the shoots incubated with some amount of soil as a source of microorganisms, inhibitory effect of the aqueous extract decreased with the incubation period. These results suggest that undecomposed and decomposing shoots of manilagrass in thatch layer may play an important role in vegetation flora and growth in manilagrass fields.

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