White powdery mildew, what do I do?

Sick Plants & Problems
1083

Here are some recent studies on PM. All within the last 5 years.

https://www.researchgate.net/publication/360076937_Efficacy_of_fungicide_treatments_against_hemp_powdery_mildew_in_the_greenhouse_in_Tennessee_2021_V049

https://www.researchgate.net/publication/338723950_Cross-Infectivity_of_Powdery_Mildew_Isolates_Originating_from_Hemp_Cannabis_sativa_and_Japanese_Hop_Humulus_japonicus_in_New_York

https://www.researchgate.net/publication/381726012_The_co-occurrence_of_two_powdery_mildew_species_on_Cannabis_sativa_in_the_Czech_Republic

https://www.researchgate.net/publication/354267693_First_Report_of_Powdery_Mildew_Caused_by_Podosphaera_macularis_on_Hemp_in_Oregon

https://www.researchgate.net/publication/347321566_Evaluation_of_disease_management_approaches_for_powdery_mildew_on_Cannabis_sativa_L_marijuana_plants

https://www.researchgate.net/publication/376969567_NLR-_and_mlo-Based_Resistance_Mechanisms_against_Powdery_Mildew_in_Cannabis_sativa

https://www.researchgate.net/publication/375645651_Holomorph_morphology_and_molecular_phylogeny_of_Podosphaera_macularis_causing_powdery_mildew_on_Humulus_scandens_in_Korea

https://www.researchgate.net/publication/354334968_Discovery_and_Genetic_Mapping_of_PM1_a_Powdery_Mildew_Resistance_Gene_in_Cannabis_sativa_L

https://www.researchgate.net/publication/353522996_Limited_effect_of_environmental_stress_on_cannabinoid_profiles_in_high-cannabidiol_hemp_Cannabis_sativa_L

https://www.researchgate.net/publication/339467474_Population_Diversity_and_Structure_of_Podosphaera_macularis_in_the_Pacific_Northwestern_US_and_Other_Populations

https://www.researchgate.net/publication/380030844_Fungal_contamination_of_medicinal_cannabis_A_bibliometric_evaluation_trends_and_future_perspectives

https://www.researchgate.net/publication/348985155_First_Report_of_Powdery_Mildew_Caused_by_Golovinomyces_ambrosiae_on_Cannabis_sativa_in_Oregon

https://www.researchgate.net/publication/359795305_Suppression_of_hemp_powdery_mildew_using_root-applied_silicon

1084

You should go watch that hash church episode. It’ll teach you way more than those studies, lol!

1 Like
1085

Actually the first study shows how they used bonide sulfur to completely eradicate mildew. A Good start. The final study is a joke though. Silica fails.

3 Likes
1087

Regarding Sulfur:
This is completely anecdotal, and might just be correlation, rather than causation, but my plants came down with what Im prettry sure is fusarium. I gave them a heavy spray of sulfur, and a watering with some sulfur. Then for a few waterings, Id thrown in a splash of sulfur.

They’re 3 weeks into flower, and so far, it doesnt appear to be spreading any further. My plan was, and is, the first sign that its spreading within the plant, i’ll cull them.

Btw, there’s a chance it isnt fusarium, thats just what I came up with. If anyone checks it out, and knows different, it would be nice to know, but in mean time Im treating as if it is.

Also, on a side note, its my understanding sulfur is a good general pest control too, but IDK.

2 Likes