In order to identify the visual symptoms of micronutrient deficiency and of mineral content in the guava young plant leaves, seedlings were grown in a greenhouse experiment in seven different treatments as follows: (1) complete; (2) without B; (3) without Co; (4) without Fe; (5) without Mn; (6) without Mo; and (7) without Zn. The solutions were changed every 20 days. All symptoms were described and the deficiencies due of boron, copper, iron, manganese and zinc could be clearly noticed in the leaves. This fact was not observed for Mo. After 65 days, the third pair of leaves was collected, to assess the nutrient contents which were in mg kg-1: B (7 - 43); Cu (2 - 6); Fe (55 - 117); Mn (5 - 23) e Zn (9 - 14). The first number in parentheses represents the deficient treatment, and the second the complete treatment. Several interactions were found, such as Cu with Fe, Cu with Mn, Fe with B, Fe with Zn, Mn with Zn, B with Ca and B with P. A decrease on dry matter yield could be observed when certain micronutrients were not applied, except for the one in which Mo was absent.
nutrient solution; nutritional deficiency; deficiency symptoms; Psidium guajava
