1985 Fiscal Year Final Research Report Summary
Studies on the Control of Soil-borne Diseases by Bacterization of Crop Seeds.
| Project/Area Number |
58860011
|
|---|
| Research Category |
Grant-in-Aid for Developmental Scientific Research
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
植物保護
|
|---|
| Research Institution | Hokkaido University |
|---|
Principal Investigator |
|
|---|
| Project Period (FY) |
1983 – 1985
|
| Keywords | Sugar beet / Rhizoplane microflora / Bacterization / Fluorescent Pseudomonas / Antibiosis / Plant growth promotion / 立枯病抑制効果 |
|---|
| Research Abstract |
The rhizoplane microfloras of sugar beets which were cultivated in Hokkaido University soil and Hokkaido National Agricultural Experimental Station soil were observed. The number of rhizoplane microorganisms of sugar beets which were cultivated in pots in greenhouse continued to increase to 3 weeks after sowing and kept constant level to harvesting period.
There were almost no differences of numbers and groups of microorganisms between both soils except fluorescent Pseudomonas, which was high at Ag. Exp. Sta. soil. The seedlings which were raised in paper pots with Agr. Exp. Sta. soil were transplanted to both fields, and were observed about rhizoplane microflora monthly. The results were almost the same with the former experiment.
However, in this case, number of fluorescent Pseudomonas was not different between both fields. During these experiments, 1026 isolates were isolated and tested antibiotic activity to pathogens of damping off. The rate of antibionts was higher in Agr. Exp. Sta. field.
In any case, antibionts were present on the root and could be isolates allover the cultural period. The great portion of antibionts was fluorescent Pseudomonas. Out of 1026 isolates, 145 (14%) were antibiotic to Aphanomyces cochlioides and made the inhibition zones. Most of these antibionts were also antibiotic to Pythium spp. and Rhizoctonia spp. Sugar beet seeds were inoculated with highly antibiotic bacteria and sowed in the paper pots. The results showed that there were the bacteria which promoted germination of seeds, which increased the top weights and/or roots of seedlings, and which prevented the damping off. Most of these were fluorescent Pseudomonas.
|
