Hi buddy.... unluckily leaf septoria, also known as leaf septoria, or "yellow spots on the leaves", is a plant disease caused by a certain fungus called septoria lycopersici.
This fungus typically winters on dead leaves or common garden weed. Mushroom spores can also settle on gardening tools such as posts and nets, and if conditions are favorable, they begin to develop.
Septoria can be extremely harmful to plants. It can cause severe leaf damage and impair the growth of various plant species, including tomatoes, parsley, and of course cannabis as well.
As the name suggests, leaf septoria is characterized by brown and yellow spots that develop on the front and back of the leaf. The spots are mostly round in shape, with light or dark brown edges, and more gray in the center. Typically, each spot has dimensions from 1.5 to 6.5mm.
Septoria usually affects plants that are just starting their flowering phase. The disease initially appears on the lower located leaves. As the infection spreads, the spots also develop on the top of the plant, involving numerous leaves.
Diseased leaves usually turn yellow, then brown, and eventually wither completely. Leaf septoria usually does not spread to fruit. In the case of cannabis, the flowers are not infected.
If not taken promptly, the disease can destroy a large number of leaves. This causes severe stress in the plant, and often a disruption of development. As a result, the harvest will be drastically reduced. The risk of leaf septoria is particularly high in areas where the climatic conditions are very humid for long periods.
Good luck with your grow mate!!💪🙏