Biometric characteristics and visual diagnosis of safflower plants under macro and micronutrient omission

Safflower is primarily intended to produce oil for human consumption, having the potential for biodiesel production. This study aimed to evaluate macro and micronutrients omission effect on biometrics and visual diagnosis of nutritional deficiencies in safflower plants grown in nutrient solution. Research was conducted in a greenhouse. Nutrient solutions containing all nutrients and with individual omissions of nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, boron, copper, iron, manganese, molybdenum and zinc were used. The design was completely randomized, with four repetitions. Visual diagnosis of nutrient deficiency symptoms and biometric characteristics were assessed. Data were subjected to analysis of variance and Scott-Knott’s test was applied when significant, both up to 5% probability. Among primary macronutrients, nitrogen, followed by phosphorus, caused the highest reductions in all the analyzed variables in safflower plants. Among secondary macronutrients, calcium absence caused the highest reductions, and the need for these three nutrients did not allow for plants to complete their life cycle. Macronutrient omission showed the most severe symptoms in relation to micronutrients.