@article {4519, title = {Gomose da ac{\'a}cia-negra: etiologia, an{\'a}lise temporal, perdas e controle gen{\'e}tico.}, journal = {Boletim de Pesquisa e Desenvolvimento, Embrapa Florestas, Minist{\'e}rio da Agricultura}, volume = {31}, year = {2007}, pages = {28 p.}, abstract = {

Gummosis is one of the most serious phytosanitary problems of black wattle (Acacia mearnsii) in the State of Rio Grande do Sul, Brazil. The objectives of this work were: 1) to identify the species of Phytophthora associated with gummosis; 2) to analyze the temporal distribution of the gummosis; 3) to quantify losses caused by this disease; and 4) to rank black wattle lines based on resistance to gummosis. The major results were: Phytophthora nicotianae and P. boehmeriae are the causal agent of gummosis on black-wattle in Brazil. This disease was found in all the surveyed black-wattle plantations and the species P. nicotianae was the major species found in the samples, suggesting that this is the main species causing this disease in Brazil. It was found two kinds of symptoms: 1) gummosis at the base of the trunks, associated to P. nicotianae; e 2) gummosis spread on the trunk, associated to P. boehmeriae. Plants killed by gummosis or other causes showed exponential growth, and started to die after 34 months. Plants showing gummosis had losses ranging from 3,5 to 0,5\% for bark and timber production, respectively. Both, natural and artificial inoculations assays showed variation on the resistance of plants to gummosis.

A gomose {\'e} um dos mais s{\'e}rios problemas fitossanit{\'a}rios da ac{\'a}cia-negra (Acacia mearnsii) no Rio Grande do Sul. Este trabalho teve como objetivos: 1) identificar a(s) esp{\'e}cie(s) de Phytophthora associada(s) {\`a} gomose; 2) analisar a distribui{\c c}{\~a}o temporal da gomose; 3) quantificar as perdas causadas pela doen{\c c}a; e 4) agrupar os materiais gen{\'e}ticos de ac{\'a}cia-negra de acordo com o n{\'\i}vel de resist{\^e}ncia {\`a} gomose. Os principais resultados foram: Phytophthora nicotianae e P.boehmeriae s{\~a}o os agentes causais da gomose da ac{\'a}cia-negra no Brasil. A gomose de Phytophthora foi encontrada em todos os plantios de ac{\'a}cia-negra e, no levantamento, evidenciou-se a predomin{\^a}ncia de P. nicotianae, mostrando que este pat{\'o}geno {\'e} o principal agente da gomose da ac{\'a}cia-negra no Brasil. As avalia{\c c}{\~o}es em plantios comerciais em idade de corte apresentaram at{\'e} 48 \% de indiv{\'\i}duos atacados. Tanto plantas mortas por outras causas quanto plantas mortas por gomose cresceram exponencialmente, e as mortes come{\c c}aram a partir do 34{\textordmasculine} m{\^e}s. Os dados mostraram perdas de produ{\c c}{\~a}o de at{\'e} 3,5 \% para casca e at{\'e} 0,5 \% para madeira nas {\'a}rvores com gomose. Tanto por infec{\c c}{\~a}o natural quanto por inocula{\c c}{\~a}o artificial, ocorreram varia{\c c}{\~o}es entre as proced{\^e}ncias quanto a resist{\^e}ncia {\`a} gomose.

}, issn = { 1980-041X}, url = {http://www.infoteca.cnptia.embrapa.br/infoteca/bitstream/doc/312305/1/BPD31CD.pdf}, author = {Santos, A. F. dos and Luz, E.D.M.N. and Maffia, L.A. and Souza, J.T.} }