Which symptom is primarily associated with potassium nutritional deficiency in plants?

Potassium nutritional deficiency in plants is primarily associated with yellowing leaf tips and margins. This symptom occurs because potassium is essential for various physiological processes within the plant, including photosynthesis and the regulation of stomatal opening. When plants lack potassium, they are unable to maintain proper water balance and nutrient transport, leading to compromised leaf health and the characteristic chlorosis, or yellowing, that starts at the tips and edges of the leaves.

In addition to yellowing, potassium deficiency can cause other symptoms, such as poor fruit development and increased susceptibility to disease. However, the yellowing of leaf tips and margins is the most recognizable and definitive symptom specifically linked to potassium deficiency. Recognizing and addressing this deficiency is crucial for promoting plant health and optimizing growth, particularly in potassium-demanding crops.