''Lasiodiplodia theobromae'' is a

plant pathogen Plant pathology (also phytopathology) is the scientific study of diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Organisms that cause infectious disease include fungi, oomyc ...

with a very wide

host A host is a person responsible for guests at an event or for providing hospitality during it. Host may also refer to: Places * Host, Pennsylvania, a village in Berks County People *Jim Host (born 1937), American businessman * Michel Host ...

range. It causes rotting and

dieback Dieback may refer to a number of plant problems and diseases including: * Forest dieback caused by acid rain, heavy metal pollution, or imported pathogens * The death of regions of a plant or similar organism caused by physical damage, such as from ...

in most species it infects. It is a common post harvest fungus disease of citrus known as stem-end rot. It is a cause of bot canker of grapevine.Identification and Pathogenicity of Lasiodiplodia theobromae and Diplodia seriata, the Causal Agents of Bot Canker Disease of Grapevines in Mexico. J. R. Úrbez-Torres, G. M. Leavitt, J. C. Guerrero, J. Guevara and W. D. Gubler, Plant Disease, April 2008, Volume 92, Number 4, pages 519-529, It also infects ''

Biancaea sappan ''Biancaea sappan'' is a species of flowering tree in the legume family, Fabaceae, that is native to tropical Asia. Common names in English include sappanwood and Indian redwood. Sappanwood is related to brazilwood (''Paubrasilia echinata''), ...

'', a species of flowering tree also known as Sappanwood. On rare occasions it has been found to cause fungal keratitis, lesions on nail and subcutaneous tissue. It has been implicated in the widespread mortality of baobab ('' Adansonia digitata'') trees in Southern Africa. A preliminary study found the deaths to have a complex set of causes requiring detailed research.

Host and symptoms

Papaya (Carica papaya) Lasiodiplodia fruit rot

''L. theobromae'' causes diseases such as dieback, blights, and root rot in a variety of different hosts in tropical and subtropical regions. These include

guava Guava () is a common tropical fruit cultivated in many tropical and subtropical regions. The common guava ''Psidium guajava'' (lemon guava, apple guava) is a small tree in the myrtle family ( Myrtaceae), native to Mexico, Central America, the ...

coconut The coconut tree (''Cocos nucifera'') is a member of the palm tree family ( Arecaceae) and the only living species of the genus ''Cocos''. The term "coconut" (or the archaic "cocoanut") can refer to the whole coconut palm, the seed, or the ...

papaya The papaya (, ), papaw, () or pawpaw () is the plant species ''Carica papaya'', one of the 21 accepted species in the genus ''Carica'' of the family Caricaceae. It was first domesticated in Mesoamerica, within modern-day southern Mexico and ...

, and grapevine. Botryosphaeria dieback, which is formerly known as ''bot canker'', is characterised by a range of symptoms that affect grapevine in particular. These symptoms affect different areas on the plant and can be used to diagnose this disease along with other factors. In the trunk and cordon of the plant symptoms include cankers coming out of the wounds, wedge shaped lesions when cut in cross sections and dieback. Dieback is characterized as a ‘dead arm’ and a loss of spur positions. More symptoms include stunted shoots in the spring, delay or lack of growth in the spur positions of the bud burst, bleached canes and necrotic buds. Bud necrosis, bud failure, and the dieback of arms are all a result of the necrosis of the hosts vascular system. It can also affect the fruit of

durian The durian (, ) is the edible fruit of several tree species belonging to the genus ''Durio''. There are 30 recognised ''Durio'' species, at least nine of which produce edible fruit. ''Durio zibethinus'', native to Borneo and Sumatra, is the onl ...

s such as '' Durio graveolens''.

Disease cycle

The fungus over-winters as pycnidia on the outside of diseased wood. The pycnidia produces and releases two-celled, dark brown, striated conidia. The conidia are then dispersed by wind and rain splash, spreading the fungi to other vines, and from one part of the vine to another. Disease develops when conidia land on freshly cut or damaged wood. The conidia germinate the tissue of the wood and start causing damage to the vascular system. Cankers begin to form around the initial infection point and eventually complete damage of the vascular system causes necrosis and dieback of the wood. In some instances, pseudothecia form on the outside of cankers and produce ascospores which are then dispersed like conidia and infect surrounding wounds.

Management

There are many different procedures that can be implemented to manage dieback in a vineyard. These can either be done to prevent further infection by breaking the disease cycle or to recover plants after initial infection. Good hygiene must be practiced when removing infection sources in order to prevent further infection to the rest of the vineyard as well as to avoid cross contamination. Strategies that can be used for prevention and recovery are listed in the table below:

References

External links

USDA ARS Fungal Database
* {{Taxonbar, from=Q6493323 Botryosphaeriaceae Fungal tree pathogens and diseases Cacao diseases Fungal citrus diseases Grapevine trunk diseases