Persistent Link:
http://hdl.handle.net/10150/226093
Title:
Studies of the Biology and Control of Brown Heartwood Rot on Lemon Trees in 2000
Author:
Matheron, Michael E.; Porchas, Martin
Affiliation:
University of Arizona, Yuma Agricultural Center, Yuma, AZ
Issue Date:
Feb-2002
Publisher:
College of Agriculture, University of Arizona (Tucson, AZ)
Journal:
Citrus and Deciduous Fruit and Nut Research Report
Abstract:
Brown heartwood rot is commonly found in mature lemon groves in southwestern Arizona. Two basidiomycete fungi, Antrodia sinuosa and Coniophora eremophila, have been isolated from symptomatic trees. Similarities between the two pathogens include the following: each fungus grows optimally at 30 to 35°C, neither organism produces a fleshy fruiting body, they colonize lemon trees primarily through branch fractures and other non-pruning wounds, and both cause a brown wood rot in infected trees. A major difference between the two pathogens is that Antrodia forms spore-producing fruiting bodies on infected wood within lemon groves, whereas fruiting on lemon wood infected by Coniophora has not been observed. The rate of wood decay in lemon branches inoculated with Antrodia is at least three times greater than that caused by Coniophora. Wood decay columns produced by either fungus from late spring to early autumn were at least three times larger than those that developed from late autumn to early spring. When inoculated with either pathogen, the length of wood decay columns on branches 10 mm in diameter was numerically smaller than those on branches 20 and 40 mm in diameter. Wood decay on Lisbon lemon branches inoculated with either Antrodia or Coniophora was significantly greater than that on Marsh grapefruit, Orlando tangelo, and Valencia orange. Treatment of lemon branch inoculation sites with azoxystrobin or propiconazole at 20 g of active ingredient per liter of solution reduced the resultant length of wood decay columns by 61 and 77%, respectively, for Antrodia, and 92 and 85%, respectively, for Coniophora. When selected desert plants were inoculated, Antrodia produced wood decay columns on Palo Verde, salt cedar, greasewood, and mesquite branches that were much shorter than those recorded on Lisbon lemon branches. On the other hand, Coniophora produced longer wood decay columns on salt cedar and mesquite than on Lisbon lemon, whereas wood rot on lemon was greater than that on Palo Verde and greasewood. Current disease management strategies include minimizing branch fractures and other non-pruning wounds, and periodic inspection of trees and removal of infected branches, including physical removal of all wood infected with Antrodia from the grove site.
Keywords:
Agriculture -- Arizona; Citrus fruits -- Arizona; Lemon -- Arizona; Lemon -- Diseases
Series/Report no.:
AZ1275; Series P-129
Sponsors:
Arizona Citrus Research Council

Full metadata record

DC FieldValue Language
dc.titleStudies of the Biology and Control of Brown Heartwood Rot on Lemon Trees in 2000en_US
dc.contributor.authorMatheron, Michael E.en_US
dc.contributor.authorPorchas, Martinen_US
dc.contributor.departmentUniversity of Arizona, Yuma Agricultural Center, Yuma, AZen_US
dc.date.issued2002-02-
dc.publisherCollege of Agriculture, University of Arizona (Tucson, AZ)en_US
dc.identifier.journalCitrus and Deciduous Fruit and Nut Research Reporten_US
dc.description.abstractBrown heartwood rot is commonly found in mature lemon groves in southwestern Arizona. Two basidiomycete fungi, Antrodia sinuosa and Coniophora eremophila, have been isolated from symptomatic trees. Similarities between the two pathogens include the following: each fungus grows optimally at 30 to 35°C, neither organism produces a fleshy fruiting body, they colonize lemon trees primarily through branch fractures and other non-pruning wounds, and both cause a brown wood rot in infected trees. A major difference between the two pathogens is that Antrodia forms spore-producing fruiting bodies on infected wood within lemon groves, whereas fruiting on lemon wood infected by Coniophora has not been observed. The rate of wood decay in lemon branches inoculated with Antrodia is at least three times greater than that caused by Coniophora. Wood decay columns produced by either fungus from late spring to early autumn were at least three times larger than those that developed from late autumn to early spring. When inoculated with either pathogen, the length of wood decay columns on branches 10 mm in diameter was numerically smaller than those on branches 20 and 40 mm in diameter. Wood decay on Lisbon lemon branches inoculated with either Antrodia or Coniophora was significantly greater than that on Marsh grapefruit, Orlando tangelo, and Valencia orange. Treatment of lemon branch inoculation sites with azoxystrobin or propiconazole at 20 g of active ingredient per liter of solution reduced the resultant length of wood decay columns by 61 and 77%, respectively, for Antrodia, and 92 and 85%, respectively, for Coniophora. When selected desert plants were inoculated, Antrodia produced wood decay columns on Palo Verde, salt cedar, greasewood, and mesquite branches that were much shorter than those recorded on Lisbon lemon branches. On the other hand, Coniophora produced longer wood decay columns on salt cedar and mesquite than on Lisbon lemon, whereas wood rot on lemon was greater than that on Palo Verde and greasewood. Current disease management strategies include minimizing branch fractures and other non-pruning wounds, and periodic inspection of trees and removal of infected branches, including physical removal of all wood infected with Antrodia from the grove site.en_US
dc.subjectAgriculture -- Arizonaen_US
dc.subjectCitrus fruits -- Arizonaen_US
dc.subjectLemon -- Arizonaen_US
dc.subjectLemon -- Diseasesen_US
dc.identifier.urihttp://hdl.handle.net/10150/226093-
dc.relation.ispartofseriesAZ1275en_US
dc.relation.ispartofseriesSeries P-129en_US
dc.description.sponsorshipArizona Citrus Research Councilen_US
All Items in UA Campus Repository are protected by copyright, with all rights reserved, unless otherwise indicated.