Abiotic diseases
Diseases from abiotic (non-living) causes often arise suddenly and resemble disease caused by living organisms. They also predispose plants to other diseases. For example, drought-stressed plants become more susceptible to fungal cankers. The most common abiotic diseases in cannabis are nutrient deficiencies. Deficiencies of mobile nutrients (N, P, K, Mg, B, Mb) begin in large leaves at the bottom of plants, while less mobile nutrients (Mn, Zn, Ca, S, Fe, Cu) usually begin in young leaves near the top. Pollution could also cause diseases. Sulfor dioxide causes interveinal leaf chlorosis and hydrogen fluoride cause complete chlorosis of cannabis. Automobile-polluted plants produce fewer stomates but more trichomes per leaf area. Genetic diseases are common in cannabis. One of the authors describes some consequences of inbred hemp – short stature (only 68% the height of normal hemp), shorten lifespan (vegetative growth 9 weeks shorter than normal plants), production of sterile seeds and increased susceptibility to fungal diseases. [1]
