Effect of the stem blight pathogen, Phomopsis emicis, and the weevil, Perapion antiquum, on the weed Emex australis

The stem blight pathogen, Phomopsis emicis, is widespread on Emex australis throughout those regions of southern Australia with a Mediterranean climate. Host specificity tests showed that P. emicis was able to cause leaf lesions or stem collapse on five closely related species, E. australis, E. spinosa, Rumex alcockii, R. dumosus and R. pulcher, in the Polygonaceae. Two of these species, R. alcockii and R. dumosus, are native to Australia and the others are introduced weeds. P. emicis was able to colonize the wounded or senescent tissue of several other plant species, thereby demonstrating its facultative saprophytic ability. There was evidence that P. emicis was able to survive as an endophyte in Muehlenbeckia adpressa and Polygonum aviculare.

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Antagonistic inhibition analysis and biocontrol of asparagus stem blight Phomopsis asparagi

CHINESE JOURNAL OF ECO-AGRICULTURE ◽

10.3724/sp.j.1011.2009.01229 ◽

2009 ◽

Vol 17 (6) ◽

pp. 1229-1233

Author(s):

Li-Ping MA ◽

Bian-Qing HAO ◽

Shu QIN ◽

Xiong-Wu QIAO

Keyword(s):

Stem Blight ◽

Phomopsis Asparagi ◽

Inhibition Analysis

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Factors Promoting Pycnidia Production of Didymella bryoniae, the Causal of Gummy Stem Blight in Cucurbits

Egyptian Journal of Phytopathology ◽

10.21608/ejp.2017.89736 ◽

2017 ◽

Vol 45 (1) ◽

pp. 173-187

Author(s):

Abdel-Fattah El-Wakil ◽

Amal Khalil ◽

Ibrahim El -Abbasi

Keyword(s):

Didymella Bryoniae ◽

Stem Blight ◽

Gummy Stem Blight

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QTL Mapping for Gummy Stem Blight Resistance in Watermelon (Citrullus spp.)

Plants ◽

10.3390/plants10030500 ◽

2021 ◽

Vol 10 (3) ◽

pp. 500

Author(s):

Eun Su Lee ◽

Do-Sun Kim ◽

Sang Gyu Kim ◽

Yun-Chan Huh ◽

Chang-Gi Back ◽

...

Keyword(s):

Chromosome 8 ◽

Chromosome 6 ◽

Potential Candidate ◽

Stem Blight ◽

Gummy Stem Blight ◽

F2 Population ◽

Leaf Lesion ◽

Phenotypic Variations ◽

A Minor ◽

Selection Of

Watermelon (Citrulluslanatus) is an economically important fruit crop worldwide. Gummy stem blight (GSB) is one of the most damaging diseases encountered during watermelon cultivation. In the present study, we identified quantitative trait loci (QTLs) associated with GSB resistance in an F2 population derived from a cross between maternal-susceptible line ‘920533’ (C. lanatus) and the paternal-resistant line ‘PI 189225’ (C. amarus). The resistance of 178 F2 plants was assessed by two different evaluation methods, including leaf lesion (LL) and stem blight (SB). To analyze the QTLs associated with GSB resistance, a linkage map was constructed covering a total genetic distance of 1070.2 cM. QTL analysis detected three QTLs associated with GSB resistance on chromosome 8 and 6. Among them, two QTLs, qLL8.1 and qSB8.1 on chromosome 8 identified as major QTLs, explaining 10.5 and 10.0% of the phenotypic variations localizing at same area and sharing the same top markers for both LL and SB traits, respectively. A minor QTL, qSB6.1, explains 9.7% of phenotypic variations detected on chromosome 6 only for the SB trait. High-throughput markers were developed and validated for the selection of resistant QTLs using watermelon accessions, and commercial cultivars. Four potential candidate genes were predicted associated with GSB resistance based on the physical location of flanking markers on chromosome 8. These findings will be helpful for the development of watermelon cultivars resistant to GSB.

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Temporal and spatial dynamics of watermelon gummy stem blight epidemics

European Journal of Plant Pathology ◽

10.1007/s10658-010-9674-1 ◽

2010 ◽

Vol 128 (4) ◽

pp. 473-482 ◽

Cited By ~ 5

Author(s):

Adalberto C. Café-Filho ◽

Gil R. Santos ◽

Francisco F. Laranjeira

Keyword(s):

Spatial Dynamics ◽

Stem Blight ◽

Gummy Stem Blight ◽

Temporal And Spatial

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Boscalid Insensitivity Documented in Didymella bryoniae Isolated from Watermelon in Florida and North Carolina

Plant Health Progress ◽

10.1094/php-2012-0518-01-br ◽

2012 ◽

Vol 13 (1) ◽

pp. 42

Author(s):

Katherine L. Stevenson ◽

Anthony P. Keinath ◽

Anna Thomas ◽

David B. Langston ◽

Pamela D. Roberts ◽

...

Keyword(s):

North Carolina ◽

South Carolina ◽

High Frequency ◽

In Vitro Assays ◽

Didymella Bryoniae ◽

Triazole Fungicides ◽

Stem Blight ◽

Gummy Stem Blight ◽

Commercial Mixture

The fungicide Pristine, a commercial mixture of pyraclostrobin and boscalid, has been used widely on watermelon and other cucurbits to control gummy stem blight, caused by the fungus Didymella bryoniae. Since 2007, isolates of D. bryoniae insensitive to boscalid have been found in Georgia, Indiana, and South Carolina. Most isolates of D. bryoniae obtained in 2009 and 2010 from diseased watermelon leaves collected in several counties in Florida and North Carolina were found to be insensitive to boscalid using in vitro assays. Gummy stem blight would not be effectively managed with Pristine in any of the counties where samples were collected due to the high frequency of insensitivity to boscalid. Fortunately growers can instead use several triazole fungicides registered for use on cucurbits since 2009. Accepted for publication 30 March 2012. Published 18 May 2012.

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