Lung VQ Scan. Also known as lung or pulmonary ventilation (V) and perfusion (Q) scans. A lung VQ scan is an imaging test that uses a ventilation (V) scan to measure air flow in your lungs and a perfusion (Q) scan to see where blood flows in your lungs. It uses special x ray scanners outside of your body to create pictures of air and blood flow patterns in your lungs.
Yellow leaf spot, also known as leaf septoria, are caused by Septoria cannabis and S. neocannabina. These are fungal pathogens aimed specifically at marijuana plants. It is brought about by warm weather and rain and effect marijuana grown outdoors.
Magnesium Deficiency. Problem: A light green or yellow coloring will begin to show on the veins and edges of the lower & older leaves-this is one of the classic signs of cannabis magnesium deficiency. Magnesium is a mobile nutrient, which means that the plant can move it from old leaves to new leaves.