Name: Guignardia citricarpa Kiely. Anamorph: Phyllosticta citricarpa (McAlpine) Van der Aa (macroconidial state). Synonyms: Phoma citricarpa McAlpine. Citrus black spot is a fungal disease caused by Guignardia citricarpa. This Ascomycete fungus affects citrus plants throughout subtropical climates, causing a. Guignardia citricarpa Kiely, Proceedings of the Linnean Society of New South Wales () [MB#].
|Published (Last):||24 January 2011|
|PDF File Size:||1.53 Mb|
|ePub File Size:||12.17 Mb|
|Price:||Free* [*Free Regsitration Required]|
To confirm a diagnosis of Citrocarpa Black Spot, the pathogenic fungus must be isolated in culture. Contact our curators Dr. Postharvest Fruit from black spot-infested groves often bear quiescent infections that may later develop into black spot lesions in transport or at the final destination Hall, Guignarrdia trapping and rainfall and dew measurements have been helpful in determining the timing of ascospore release and the need for fungicide applications in South Africa Kotze, Preliminary studies on Guignardia citricarpa n.
Conidia are obovate to elliptical, hyaline, nonseptate, multiguttulate with a colourless appendage and are 5.
Guignardia citricarpa (citrus black spot)
Hard spots are the most common lesions. If you would like to know more about cookies and how they work, please visit www. No pycnidia form on these lesions and the pathogen is difficult to isolate. These spots are crater-like with a light centre, a dark-brown to black rim, and often have a green halo on mature orange fruit. Diaporthe endophytica and D. Studies on the black spot of citrus Guignardia citricarpa Kiely. Application of species-specific primers in the South African citrus industry.
Effect of packhouse procedures on the viability of Phyllosticta citricarpa, anamorph of the citrus black spot pathogen. These primers are quite reliable for differentiation of the two species when used with pure cultures of the fungus. Views Read Edit View history. Epidemiology Ascospores from infected, fallen leaves are the major source of inoculum McOnie, ; Timmer, ; Kotze, Preharvest sprays of benzimidazole fungicides are effective in preventing or delaying symptom expression during transport or storage Nam et al.
Effect of climatic factors on the development and discharge of ascospores of the citrus black spot fungus.
A mancha preta dos frutos cftricos causada por Phoma citricarpa. Leaves are susceptible up to 10 months of age. Any trees that are infected with citrus black spot should be removed from the grove and disposed of.
Storability of satsuma mandarin influenced by thiophanate-methyl treatment and mechanical injuries. Preharvest sprays of benzimidazole fungicides are effective in preventing or delaying symptom expression during transport or storage Nam et al.
Notes on Taxonomy and Nomenclature Top of page The position of the black spot fungus within the Ascomycetes has been unclear. However, now that black spot is well established in areas of southern South America, fruit losses may periodically be severe.
There was a problem providing the content you requested
Close Find out more. Survival of Phyllosticta citricarpa, anamorph of the citrus black spot pathogen. Guignardia citricarpa Kiely – Guignadria. Sanitation The removal of infected, off-season fruit may be useful to reduce conidial inoculum in some situations Kotze, Development and validation of a fast PCR-based detection method for pathogenic isolates of the citrus black spot fungus, Guignardia citricarpa.
Pycnidia are often apparent in these lesions. It can be found in many countries around the world. For practical reasons we have decided not to translate all pages in several languages anymore because it was too heavy to maintain but some of the labels of the basic and advanced query pages are still available.
Symptoms include both fruit and leaf lesions, the latter being critical to inter-tree dispersal. Conidia produced on fruit can be washed down through the canopy and infect leaves and younger fruit that are still at the susceptible stage. Brain McOnie KC, Epidemiology and control of citrus black spot in South Africa. Preliminary studies on Guignardia citricarpa n. The method is sufficiently simple to allow deployment of the test in the field, for example, in the course of import inspections.
Pests and diseases of citrus fruits and treatments recommended in Sofala and Tete. Lily Eurwilaichitr and Dr. For further information, we recommend you visit the following resources: Two distinct Guignardia species associated with citrus in South Africa. Chemical Control Due to the variable regulations around de- registration of pesticides, we are for the moment not including any specific chemical control recommendations.
Gazette New South Wales, 8: If they prove successful for detection and identification of species using colonized plant material they should greatly speed diagnosis of black spot.
A colourless appendage occurs at each end. Diagnosis Top of page A method for detection of G. Distribution Maps Top of page You can pan and zoom the map.
A few black spots on as little as one piece of fruit can cause the entire shipment to be rejected. Distribution Maps of Plant Diseases, No.
Reclassification of an isolate of Guignardia citricarpa from New Zealand as Guignardia mangiferae by sequence analysis. The widespread non-pathogenic strain is now designated Guignardia mangiferae and the citrus black spot pathogen as Guignardia citricarpa.
However, treatment with guazatine or imazalil, hot water or waxing decreased the viability of the pathogen in black spot lesions Korf citriczrpa al.
Thus citficarpa probably occur throughout spring until at least mid-summer whenever conditions are favorable.