growbieanswered grow question 4 years ago Hey mate, it looks like whitefly. Here some info.
Symptoms
The obvious evidence of whitefly infestation on cannabis leaves is the presence of tiny flies every time the plants are shaken. Other symptoms of invasion include yellowed leaves with white powder on their underside.
Treatment
The stubborn whiteflies are tough to get rid of. They need to be treated persistently with various methods like planting repellent crops (e.g. basil), strategically placing yellow sticky strips, or spraying with neem oil or potassium soap.
Hope it will help you. Good luck buddy & let it grow!!