Mineral-Deficiency Symptoms Displayed by Papaya Plants Grown under Controlled Conditions

Abstract

Deficiency symptoms caused by lack of macro- and micronutrient elements were induced on papaya trees grown in sand culture in the greenhouse. The elements used in the study were N, P, K, Ca, Mg, S, Fe, Mn, and B. Lack of N and P depressed overall growth markedly, while the absence of K and Ca caused pronounced foliar symptoms. Among the micronutrients, B deficiency had the greatest influence in depressing growth and root development. Deficiencies of S, Fe, Mg, and Mn failed to retard growth or root development. Flowers set under the minus K, S, Mg, Mn, and the complete solution treatments. However, only the plants in the minus K and minus Mn treatments produced fruits. The concentration of the particular missing element in leaf tissues was lower in plants from the respective deficiency treatment than in control plants. Plants in the minus B treatment showed abnormal growth, reminiscent of papaya plants affected by the bunchy-top disease. However, latex flow was normal in B-deficient plants.