Water-insoluble urea-formaldehyde condensates as rhizosphere microflora improver - are metabolised by useful soil microorganisms but not by pathogens, and are converted to plant-available forms of nitrogen
- 专利权人:
- MITSUBISHI RAYON CO. LTD.
- 发明人:
- TERUO TAKAHASHI,YOSHIHIRO HASHIMOTO
- 申请号：
- NL19971005259
- 公开号：
- NL1005259(C2)
- 申请日:
- 1997.02.12
- 申请国别(地区):
- 荷兰
- 年份:
- 1999
- 代理人:
- 摘要：
An improver of rhizosphere microflora contains a urea-formaldehyde condensate of formula X-(NH-CO-NH-CH2)n-Y (I), where X = H or hydroxymethyl; Y = ureido or hydroxy, and n = 4 or more. (I) stimulates growth of particularly Pseudomonas, Agrobacterium and Bacillus species, but is not metabolised by many pathogens, e.g. Rhizoctonia, Fusarium and Streptomyces scabies. (I) is usually applied at 0.5-10 (preferably 2-6) g/l of soil, optionally with a fertiliser or other soil improver. (I) is made by reacting urea and formaldehyde under alkaline conditions (preferably pH 7-8) at 20-95 [deg]C for 0.5-30 hours with mole ratio 0.8-1.3. The product of this stage (mainly dimethylolurea) is then subjected to dehydration/condensation reaction at pH 3-5 and 60-80 [deg]C for 0.5-5 hours. The product from this stage has hot-water solubility not over 0.01 g/100 g and is degraded by microbes to ammonia and/or nitrate. The condensate is extracted with water at 80 [deg]C or more, for 0.5-3 hours, then dehydrated by centrifugin
- 来源网站：
- 中国工程科技知识中心
