Mapeamento genético da resistência e a influência da nutrição mineral na intensidade da mancha-de-pteridis em eucalipto

• Ano de defesa: 2011
• Autor(a) principal: Zarpelon, Talyta Galafassi
• Orientador(a): Alfenas, Acelino Couto
• Banca de defesa: Maffia, Luiz Antônio , Guimarães, Lúcio Mauro da Silva , Silveira, Silvaldo Felipe da
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Fitopatologia
• Departamento: Etiologia; Epidemiologia; Controle
• País: BR
• Palavras-chave em Português: Mapeamento genético; Mancha-de-pteridis; Eucalipto
• Palavras-chave em Inglês: Gene mapping; Mancha-of-pteridis; Eucalyptus
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE::FITOPATOLOGIA
• Link de acesso: http://locus.ufv.br/handle/123456789/1045

Cylindrocladium pteridis induces leaf blight and severe defoliation in plantations of eucalyptus in hot and humid regions. To better understand the influence of genetic and nutritional aspects of the disease, objective to: (i) evaluate the strength of five families from interspecific controlled crosses of Eucalyptus spp., aimed at mapping and QTL (Quantitative Trait Loci) detection in a full-sib family, (ii) to validate microsatellite markers close to QTLs that control resistance to defoliation and (iii) determine the effects of nitrogen (N), phosphorus (P) and potassium (K) in the intensity of blight-topteridis. In the first study, there were five QTLs, Rd-1 Rd-2, Rd-3, Rd-4, Rd-5, the family of Eucalyptus urophylla (EU11) x E. camaldulensis (EC06), which explained, respectively 22, 15, 16, 17 and 49 % resistance to defoliation. Three QTLs were detected in the parental EU11, Rd-1 and Rd-2 located on linkage group (LG) 1 and Rd-4 located on LG6; and two QTLs located on the map of the parental EC06, present in LG2 (Rd-3) and LG8 (Rd-5). Markers linked to QTL Rd-2 were validated in two unrelated families by simple linear regression analysis. In the second study, we determined also the effect of N, P and K in diseased leaf area (DFA) and defoliation (D) caused by the disease. For the D was adjusted a linear equation and the DFA a quadratic equation. The effect of phosphorus (P) in the intensity of the disease was not clearly defined, probably due to poor absorption by the plant element. High doses of K and D significantly reduced the DFA. Synergism was detected between N and K, wherein K higher doses of related lower N rates resulted in lower D and DFA. The fertilizer management, mainly potassium, in a proper and balanced clonal eucalyptus can minimize losses in timber volume due to consecutive defoliation caused by C. pteridis.