Potassium and Plant Stress

Several environmental conditions can cause stress to plants – drought, high or low temperature, high or low light intensity, salinity, acidity, poor supply of nutrients and attacked by fungi, bacteria, viruses and insects. Stressed plants grow more slowly, may show unusual growth patterns and give reduced yield. Stress affects crops directly, for example by reducing the rate of photosynthesis and so growth. However, there are other, less obvious effects within the plant. Some of the damage caused by stress is due to formation of reactive forms of oxygen during plant metabolism. Where the normal process of photosynthesis is disrupted by lack of carbon dioxide, inhibition of sugar formation or reduced rate of movement of sugars out of the leaf, the metabolic pathways are diverted to produce reactive forms of oxygen. These are highly toxic, damage cell membranes and degrade chlorophyll with resulting effects on plant growth and development.