Macronutrient deficiency in cucumber plants: impacts in nutrition, growth and symptoms

Abstract

This study aimed to assess the growth, nutrition and visual deficiency symptoms of cucumber plants as a function of macronutrient omission. The experiment was conducted in a completely randomized design, with seven treatments and four replicates, corresponding to nutrient solution without nutrient omission (CS) of Hoagland and Arnon, nitrogen (−N), phosphorus (−P), potassium (−K), calcium (−Ca), magnesium (−Mg) and sulfur (−S) omission. Omissions decreased the accumulation of macronutrients with detrimental effects in physiological variables and in the efficiency of absorption, transport and use of macronutrients, causing losses in growth and on dry mass production. Since the losses in dry mass in the shoot were up to 85%, 85%, 83%, 47%, 40% and 40% to the omission of Ca, Mg, N, P, K and S, respectively. The accumulation of macronutrients in the aerial part of cucumber plants that received the complete solution (CS) in relation to each omission (−) was 1058/75, 157/20, 958/152, 578/9, 147/5 and 142/12 for CSN/−NN, SCP/−PP, SCK/−KK, SCCa/−CaCa, SCMg/−MgMg and SCS/−SS, respectively. Therefore, the lowest macronutrients accumulation, the green color index, plant growth and dry matter production were reduced in cucumber plants. The order of limitation of macronutrients in the shoot dry matter production in cucumber plants was N = Ca = Mg > P > K = S.