As the disease progresses, the spots get larger and denser as large numbers of asexual spores are formed, and the mildew may spread up and down the length of the plant.

[4] Sexual reproduction occurs via chasmothecia (formerly cleistothecium), a type of ascocarp in which genetic recombination takes place.

Ascocarps including chasmothecia, apothecia, perithecia, and pseudothecia, are the fruiting bodies unique to fungi in the Ascomycota phylum (known as ascomycetes).

Four closely related species of plant parasites from the powdery mildew genera were found to have lost between 5 and 21 of the 48 to 52 MMR genes that are present in most other ascomycete genomes.

[9] The powdery mildew species with higher levels of MMR gene loss exhibited elevated rates of various types of mutation.

[citation needed] Powdery mildew growth can be limited by reducing humidity, such as by allowing space between plants for airflow, and pruning to thin foliage.

[10] Spray programs of conventional fungicides are advised to begin when powdery mildew symptoms and signs are first noticed.

[2] The most effective non-conventional methods of chemical control against powdery mildew are milk, natural sulfur (S8>), potassium bicarbonate, metal salts, and oils.

[13] Neem oil effectively manages powdery mildew on many plants by interfering with the fungus' metabolism and terminating spore production.

[2] Milk has long been popular with home gardeners and small-scale organic growers as a treatment for powdery mildew.

Milk is diluted with water (typically 1:10) and sprayed on susceptible plants at the first sign of infection, or as a preventative measure, with repeated weekly application often controlling or eliminating the disease.

[15] Milk has proven effective in treating powdery mildew of summer squash,[15] pumpkins,[14] grapes,[16] and roses.

[16] Dilute sprays containing sodium bicarbonate (baking soda) and vegetable or mineral oils in water are often recommended for controlling powdery mildew, but such mixtures have limited and inconsistent efficacy.

Silicon helps the plant cells defend against fungal attack by degrading haustoria and by producing callose and papilla.

[23] In 2014, resistance was induced in hexaploid bread wheat to powdery mildew via targeted mutations with the use of CRISPR and TALENS gene-editing technology.

[24] Sunflower powdery mildew is a disease caused by the pathogens Golovinomyces cichoracearum, Podosphaera xanthii, and Leveillula taurica.

[citation needed] Multiple species of fungus can cause powdery mildew of cucurbits: cucumbers, squashes (including pumpkins), luffas, melons, and watermelons.

[29] At least three other Erysiphaceae fungi can cause powdery mildew in cucurbits: The most frequent, after P. xanthii, is Erysiphe cichoracearum, the former primary causal organism throughout most of the world.

Research on biological control of powdery mildews (especially in high-value crops such as grapes) has been ongoing since the 1970s, resulting in the development of fungicides which contain A. quisqualis as the active ingredient.