1980 Volume 9 Issue 2 Pages 119-125
1. This experiment was carried out on the relationship between the occcurrence of Rhizoctonia Large Patch and the vicissitude of number of the fungi isolated from this disease, and the inhabiting range of the causal fungi.
2. The trace of autumn lesion remained during the winter dormant stage of Zoysia turfgrass, and the size and form of the trace continued into the spring lesion as it was. After that, the spring lesion developed larger and larger.
In the latter part of spring the lesion disappeared completly, then in the autumn the lesion started again.
The recovering of new turf in the summer season resulted from not only the healthy turf in contact with the lesion but the remainning turf in the bare area in late spring.
3. In this test, the occurrence of disease in the spring was from the last ten days of March or the first ten days of April to the middle of June, and the most intensive occurrence of the disease was from the middle of April to the middle of May.
In the autumn it occured from the first ten days of October to the last ten days of November.
4. The vicissitude of Rhizoctonia solani considered to cause this disease was approximately the same as the occurrence of this disease, but the fungi in the spring were isolated more frequently than in the autumn.
The number of fungi in creased before the appearence of spring and autumn lesion.
The fungi in the letter part of the spring lesion were hardly isolated at all in spite of the lesion and not complately in the summer.
But the fungi in the latter part of the autumn lesion and the dormant stage of Zoysia turfgrass had a low isolation, and before the appearence of the spring lesion was higher.
5. It's considered that the causal fungi inhabit the surface of turfgrass soil and the hyphae develop into not only the disease turf area but also the healthy turf area that is in contact with it.
