Bacterial leaf scorch (BLS) of shade trees

2007 ◽  
Author(s):  
Gould
Keyword(s):  
Shade Trees ◽  
Leaf Scorch ◽  
Bacterial Leaf Scorch

scholarly journals Evaluation of Therapeutic Treatments to Manage Oak Bacterial Leaf Scorch

2010 ◽  
Vol 36 (3) ◽  
pp. 140-146
Author(s):  
John Hartman ◽  
Ed Dixon ◽  
Shawn Bernick
Keyword(s):  
Disease Management ◽  
Growth Regulator ◽  
Late Summer ◽  
Golf Course ◽  
Tree Disease ◽  
Leaf Scorch ◽  
Street Tree ◽  
Quercus Palustris ◽  
Horse Farm ◽  
Bacterial Leaf Scorch

Bacterial leaf scorch is a very serious tree disease, especially for oaks in Kentucky, U.S. landscapes. From 2003 to 2007, several potentially therapeutic disease management treatments were tried on diseased pin oaks (Quercus palustris) growing in golf course, street tree, and horse farm environments. Treatments included root flare soil drenches of paclobutrazol, adjuvant-assisted basal trunk applications of anti-microbial compounds, and springtime root flare injections of oxytetracycline. Paclobutrazol drenches caused expected growth regulator effects but did not consistently reduce bacterial leaf scorch of golf course and street trees. Antibiotics applied directly to trunks of infected trees with an adjuvant had no effect on levels of bacterial leaf scorch. Compared to untreated trees, springtime root flare injections of oxytetracycline reduced scorch levels and delayed by about two weeks, the time of appearance of late summer scorch symptoms. Injections done three weeks after full expansion of first leaves provided better results than injections done earlier or later in the spring. Therapeutic treatments do not provide a cure for trees infected with bacterial leaf scorch, but may prolong tree life.

Pecan Bacterial Leaf Scorch, Caused by Xylella fastidiosa, Is Endemic in Georgia Pecan Orchards

2018 ◽  
Vol 19 (4) ◽  
pp. 284-287 ◽  
Author(s):  
Clive H. Bock ◽  
Jonathan E. Oliver ◽  
Chunxian Chen ◽  
Michael H. Hotchkiss ◽  
Katherine L. Stevenson ◽  
...  
Keyword(s):  
Yield Loss ◽  
Xylella Fastidiosa ◽  
Severe Disease ◽  
The United States ◽  
Susceptible Cultivar ◽  
Leaf Scorch ◽  
Central Production ◽  
Cape Fear ◽  
Production Areas ◽  
Bacterial Leaf Scorch

Pecan bacterial leaf scorch (PBLS), caused by Xylella fastidiosa, can cause severe disease in some pecan cultivars, resulting in yield loss. Only recently has some information been obtained regarding the distribution and extent of the disease in pecan in any state in the United States. With emphasis on a susceptible cultivar, Cape Fear, we sampled a total of 91 trees in eight orchards from the southwestern and central production areas in Georgia (GA) and found 60.4% of trees sampled infected, most showing symptoms of PBLS. Further multilocus sequence typing from 16 of these trees confirmed presence X. fastidiosa. The results confirm that X. fastidiosa is widespread geographically in GA, and different cultivars may be infected. This is the first definitive report confirming X. fastidiosa causing PBLS in different pecan producing areas and cultivars in GA.

scholarly journals Evidence that Xylella fastidiosa Can Cause Leaf Scorch Disease of Pecan

Plant Disease ◽  
2000 ◽  
Vol 84 (12) ◽  
pp. 1282-1286 ◽  
Author(s):  
R. S. Sanderlin ◽  
K. I. Heyderich-Alger
Keyword(s):  
Xylella Fastidiosa ◽  
Carya Illinoinensis ◽  
Symptom Development ◽  
Koch’S Postulates ◽  
Leaf Scorch ◽  
Symptomatic Tissue ◽  
Koch's Postulates ◽  
Bacterial Leaf Scorch

The disease known as pecan fungal leaf scorch has been reported to be either caused by or associated with several fungi since it was first recognized in 1972. Data are presented that indicate the disease is initiated by the fastidious xylem-limited bacterium Xylella fastidiosa. X. fastidiosa was found consistently associated with fungal leaf scorch disease of pecan (Carya illinoinensis) in commercial orchards in Louisiana. It was generally not detected in symptomless trees. The disease was reproduced by inoculation of greenhouse seedlings and grafted trees with cultures of the bacterium obtained from leaves with fungal leaf scorch. The bacterium was reisolated from symptomatic tissue of inoculated pecan seedlings, but not from symptomless plants inoculated with water to complete Koch's postulates. It is proposed that the name of the disease be changed to pecan bacterial leaf scorch because fungi do not appear to be necessary for symptom development.

scholarly journals First Report of Pecan Bacterial Leaf Scorch Caused by Xylella fastidiosa in Pecan (Carya illinoinensis) in Arizona, New Mexico, California, and Texas

Plant Disease ◽  
2017 ◽  
Vol 101 (11) ◽  
pp. 1949-1949 ◽  
Author(s):  
A. E. Hilton ◽  
Y-.K. Jo ◽  
K. Cervantes ◽  
R. A. Stamler ◽  
J. J. Randall ◽  
...  
Keyword(s):  
New Mexico ◽  
Xylella Fastidiosa ◽  
Carya Illinoinensis ◽  
First Report ◽  
Leaf Scorch ◽  
Bacterial Leaf Scorch

scholarly journals Effects of Pecan Bacterial Leaf Scorch on Growth and Yield Components of Cultivar Cape Fear

Plant Disease ◽  
2003 ◽  
Vol 87 (3) ◽  
pp. 259-262 ◽  
Author(s):  
R. S. Sanderlin ◽  
K. I. Heyderich-Alger
Keyword(s):  
Yield Components ◽  
Growth And Yield ◽  
Yield Reduction ◽  
Phosphorus Concentration ◽  
Potential Yield ◽  
Leaf Scorch ◽  
Significant Yield ◽  
Number Of Leaves ◽  
Cape Fear ◽  
Bacterial Leaf Scorch

Pecan bacterial leaf scorch (PBLS) recently was recognized to be caused by the bacterium Xylella fastidiosa. The objective of this work was to compare certain tree growth and yield components of trees with and without PBLS. The evaluations were made for 3 years (1999 to 2001) on the disease-sensitive cv. Cape Fear. At nut maturity (October) each year, the number of leaves and leaflets and the leaflet weight were significantly smaller on terminals from trees with leaf scorch than on terminals from trees not infected with X. fastidiosa. Similar amounts of defoliation occurred on bearing and nonbearing terminals. The symptomatic terminals averaged 58% fewer leaflets at the end of the growing season. The weight of terminals from diseased trees was significantly lower in 2 of the 3 years for nonbearing terminals compared with similar terminals from uninfected trees. Terminals of infected trees generally were not significantly shorter than terminals of uninfected trees. The weight of the nuts from terminals with leaf scorch was lower than the weight from uninfected trees each year. The primary effect was on kernel development, which averaged 16% lower weight. Phosphorus concentration was slightly but significantly lower in infected leaflets during October in three of six comparisons. There were no other consistent differences in the concentration of nine other elements in leaflets between diseased and uninfected terminals. PBLS is capable of causing economically significant yield reductions. Because the disease is chronic, the potential yield reduction over the life of a tree is large on disease-sensitive trees.

scholarly journals Bacterial Leaf Scorch of Landscape Trees: What We Know and What We Do Not Know

2007 ◽  
Vol 33 (6) ◽  
pp. 376-385
Author(s):  
James Sherald
Keyword(s):  
Disease Management ◽  
Urban Forest ◽  
Xylella Fastidiosa ◽  
Diagnostic Techniques ◽  
Individual Tree ◽  
Leaf Scorch ◽  
Property Owners ◽  
Symptom Awareness ◽  
Landscape Trees ◽  
Bacterial Leaf Scorch

Xylella fastidiosa has been recognized as a pathogen of landscape trees for over 25 years. Collectively, these diseases are referred to as bacterial leaf scorch (BLS). Arborists, property owners, and communities are now beginning to recognize BLS as a serious threat to the urban forest. Although advances in symptom awareness and diagnostic techniques have enabled arborists to diagnose BLS, there are many questions regarding host range, transmission, pathogeneses, disease management, and individual tree therapy that remain unanswered.

Sign in / Sign up

Export Citation Format

Share Document