Source: MiddleEast-in-24 [abridged, edited]
A disease called "black soot" struck the crops of mangoes. A member of the House of Representatives said that there were many complaints from mango growers about the threat of the disease. This year , the disease [poses a danger]. The mango crop, especially in Ismailia governorate, suffered losses of 80% in the production of mangoes. The flowering rate of mango [trees] reached 0% in some gardens.
The representative emphasized that the mango crop has been suffering for nearly 3 years from a severe collapse due to black fly. The loss of the crop [comes] in addition to the high costs of fertilizers, electricity, labor, and pesticides.
[Sooty moulds are saprophytes which live on the host's surface. They are not pathogens in the true sense because they do not invade the plant tissue, but are secondary parasites. They follow different pests (for example, scale insects, aphids, possibly the 'black flies' mentioned above) excreting honeydew which coats the plant and provides a growth substrate for the fungi. They occur on a range of hosts including many fruit trees, shrubs, and ornamentals. On mango, species of several genera (for example _Capnodium_, _Meliola_, _Tripospermum_) are known to occur.
Plants become blackened with velvety fungal growth and are usually sticky. The whole plant may be affected, the moulds are difficult to remove. They reduce plant vigour and productivity by restricting the light available to the host for photosynthesis. The moulds may also grow on plants not affected by insects if honeydew drips from overhanging vegetation. They are more likely to grow in dry conditions as rain washes the honeydew away.
Disease management mainly focuses on control of the insects and may involve pesticides, soap, or oil-based organic sprays, as well as biological control by specific predator insects.
The picture supplied with the story above does not show sooty mould symptoms. It is an archived illustration of mangoes affected by anthracnose, derived from the internet (example, fig. 3, https://www.growables.org/information/TropicalFruit/mangocommondiseases.htm).
http://healthmap.org/promed/p/15468 and http://ontheworldmap.com/egypt/map-of-egypt-max.jpg (with governorates)
Sooty mould on mango:
Sooty mould on other hosts:
http://www.annettemcfarlane.com/image/Sooty_Mould_Lg.jpg (citrus fruit),
https://content.peat-cloud.com/hd/sooty-mold-pepper-2.jpg (black pepper), and
Information on sooty mould on mango:
Main sooty mould species on mango via:
Sooty moulds on various species:
Fungal taxonomy via: