Visual and Infrared Assessment of Root Colonization of Apple Trees by Phymatotrichopsis omnivora

Root systems of 5-year-old, trellised apple trees (Malus domestica Borkh) on cv. M.7a root-stocks were assessed for the presence of fungal strands of Phymatotrichopsis omnivora (Duggar) Hennebert in two orchards in central Texas. Fungal advance within each orchard was assessed in five directions. Pa...

Description complète

Détails bibliographiques
Publié dans:Plant disease. - 1997. - 84(2000), 5 vom: 30. Mai, Seite 539-543
Auteur principal: Watson, W T (Auteur)
Autres auteurs: Kenerley, C M, Appel, D N
Format: Article en ligne
Langue:English
Publié: 2000
Accès à la collection:Plant disease
Sujets:Journal Article infrared thermometer plant disease control sclerotia soilborne pathogen
Description
Résumé:Root systems of 5-year-old, trellised apple trees (Malus domestica Borkh) on cv. M.7a root-stocks were assessed for the presence of fungal strands of Phymatotrichopsis omnivora (Duggar) Hennebert in two orchards in central Texas. Fungal advance within each orchard was assessed in five directions. Pathogen growth (P < 0.01) occurred beyond symptomatic trees along and perpendicularly across rows. In one orchard, 80% of the first asymptomatic trees were infected along rows, followed by 60% infection perpendicularly across rows. In the other orchard, there was 100% infection of the first asymptomatic trees along rows and 60% infection perpendicularly across rows. No growth was observed diagonally across rows in either orchard. Infrared readings of canopy temperature and differences between canopy temperature and air temperature were significant (P < 0.01) for predicting infection of asymptomatic, infected trees in one orchard. Trees were shown to have extensive taproot decay and infection of lateral roots before canopy symptoms began to develop. Root diameter appeared to have no effect on the growth of the fungus
Description:Date Revised 20.11.2019
published: Print
Citation Status PubMed-not-MEDLINE
ISSN:0191-2917
DOI:10.1094/PDIS.2000.84.5.539