1980 Volume 9 Issue 2 Pages 127-131
1. This experiment was carried out concerning the outbreak of Rhizoctonia Large Patch by the artificial inoculating method of Rhizoctonia solani into the Zoysia turfgrass and the outbreak conditions of this disease by this artificial inoculating method.
2. When the amounts 5-40g of the soil and wheat bran mixed culture of the causal Rhizoctonia solani isolated from this disease were inoculated to the potted turfgrass (Zoysia matrella) in 15cm diameter, the outbreak of disease was observed with the infection rate of 55-70% after 30 days, but the inoculation rate showed no difference in the results.
3. When the relationship between the outbreak of disease against the Zoysia turfgrass and the watering interval, as the rainy interval, was tested under constant soil moisture and saturated air moisture by the artificial inoculating method, the shorter the watering interval was, the higher the infection rate became.
As the result, it's considered that the outbreak develops largely in because of continual wet turf surface which was maintained by watering during the testing period.
4. The relationship between the outbreak and the removing thatch was tested by the artificial inoculating method, so that, the outbreak rate increased highly when the turf was injured in the processes of removing thatch. The improved environment did not compensate for the injuring to the turf.
5. When the outbreak of disease was tested in the growing turf stage after cutting upper stem and the spring bud stage by the arificial inoculating method, the outbreak in both stages was greatest when the young stem came in contact with the inoculant.
6. The susceptibility of disease was tested in the Zoysia turfgrass by the artificial inoculating method, consequently, the difference of outbreak was as follows (from the most susceptible) Zoysia matrella (broad leaf) >Zoysia matrella (narrow leaf) > Zoysia japonica > Zoysia tenuifolia.
