Data/hora: 01/06/2024 06:32:27

Biblioteca(s): 	Embrapa Florestas; Embrapa Meio-Norte.	
Data corrente: 	06/06/1995	
Data da última atualização: 	17/08/2015	
Autoria: 	GRECO, A. R.	
Título: 	Effect of root diseases and site preparation on the growth and nutrient status of bareroot and container grown douglas-fir seedlings.	
Ano de publicação: 	1978	
Fonte/Imprenta: 	1978.	
Páginas: 	71 f.	
Idioma: 	Inglês	
Notas: 	Thesis (Master of Science) - University of Washington, Washington.	
Conteúdo: 	Bareroot seedlings had higher survival than container seedlings when burning or scarificatiion was used as site treatments. In the unburned (control) treatment there was no apparent difference in survival of bareroot or container seedlings. Shoot biomass and needle nitrogen content were significantly higher for bareroot seedlings in the burned and acarified treatments versus the unburned treatment. Seedlings in the unburned treatment. Seedlings  in the unburned treatment had lower levels of ectomycorrhizal root tips, shorter mean needle length, lower mean height increment, narrower mean root collar diameter, and higher number of seedlings suspected to be infectted with P. weirii compared to the seedlings grow in the scarified and burned treatments, but these variables were not statiscally significant. It appears that when Douglas-fir bareroot seedlings are used in artificial regeneration, either burning or scarification rather thanunburned should be the recommended site treatment pratice. When container Douglas-fir seedlings are used for regeneration, it appears that unburned treatment will result in the highest survival of seedlings. There was no significant diference in needle nutrient content, number of ectomycorrhizal root tips, or seedling morphological measurements made on container seedlings in all three treatments. Survival of seedlings was the major variable affecting the choice of site treatment most suitable for container seedling regeneration. Seedling vigor was directly related to the number of ectomycorrhizal root tips. Presence of Rhizina undulata did appear to have any measurable effect on seedling growth or survival in the burned site. The effect of site treatment on the presence of Phellinus weirii in the bareroot seedlings was apparent in the unburned site. The seedlingsthat showed the highest number of suspected P. weirii had the lowest number of mycorrhizal root tips, lower needle N content,and significantlylower shoot biomass weight in comparison to the burned and scarified treatments. The effect of P. weirii on container seedlings was not as apparent in the three different treatments. Scarification appeared to have limiting effects on P. weirii by reducing below ground residues in which the fungus survive.	
Palavras-Chave: 	Douglas-fir.	
Thesagro: 	Crescimento; Doença; Muda; Nutrição; Nutriente; Raiz; Tratamento.	
Thesaurus Nal: 	Pseudotsuga menziesii; seedlings.	
Categoria do assunto: 	--
X Pesquisa, Tecnologia e Engenharia	
Registro original: 	Embrapa Florestas (CNPF)	
Exemplares: 	CPAMN - (7496-1) - ADD - TS - PP - T 39/78 -  - 1978.00039 - DIS
CNPF - (29388-1) - ADC - TS - -- - TS0381 -  - TS0381 - DIS