Fitopatogene gljive ubrajamo u žive uzročnike bolesti. Fitopatogene gljive uzrokuju 75% biljnih bolesti, a u biljke mogu prodrijeti na tri načina, to su: prodiranje kroz prirodne otvore biljke, prodiranje kroz nastale mehaničke ozlijede tkiva biljaka ili izravno prodiranje kroz neozljeđeno tkivo biljaka. Fitopatogene gljive svrstavamo u skupinu parazita jer su svoju prehranu specijalizirale za uzimanje hrane od domadara kojem pri tomu nanose štetu. Mogu biti obligatni i fakultativni paraziti. Osim prema potrebama za domadarom, fitopatogene gljive možemo podijeliti i prema mjestu parazitiranja. Kroz evoluciju su se prilagodile mnogim različitim načinima rasprostranjivanja, pa se tako mogu rasprostranjivati putem vjetra, vektorskih organizama, oruđa za obradu tla i na mnoge druge načine. U ovom radu obrađeno je nekoliko rodova fitopatogenih gljiva koje su šioko rasprostranjene. To su rod Cercospora koji uzrokuju pojavu pjegavosti na listovima, rod Coniothyrium koji uzrokuje pojavu nekroza na mladicama eukaliptusa, rod Erysiphe koji uzrokuje pojavu pepelnice i mnogi drugi rodovi i vrste. Osim spomenutih rodova, obrađene su i najčešće bolesti koje pogađaju poljoprivredne i voćarske kulture, a to su plamenjača krumpira, plamenjača vinove loze, krastavost lista i ploda jabuke, kovrčavost lista breskve te smeđa i žuta hrđa pšenice.

Phytopathogenic fungi belong to the living causers of the disease Phytopathogenic fungi cause 75% of plant diseases, and the fungus can penetrate into plants in three ways: penetrating through the natural openings of the plant, penetrating through the resulting mechanical damage to the plant tissue or directly penetrating through untreated plant tissue. Phytopathogenic fungi are classified into a group of parasites because their diet specializes in taking food from a hosts and they are making damage to them while they are doing that. They can be compulsory and optional parasites. In addition to domicile needs, phytopathogenic fungi can also be divided according to the parasitic site. They evolved through evolution through many different ways of spreading, so they can spread through wind, vectorial organisms, soil treatment tools and in many other ways. This paper deals with several genera of phytopathogenic fungi that are severely widespread. These are the type of Cercospora that cause the appearance of clotting on the leaves, the Coniothyrium genus that causes the appearance of necrosis on the eucalyptus buds, the Erysiphe genus, which causes the appearance of leech and many other genera and species. Apart from the aforementioned breeds, most common diseases affecting agricultural and fruit crops are also treated, such as potato flakes, grape vines, leaf cuttings and apple fruits, peach leaf curls, and brown and yellow wheat rust.