Young sweet corn plants (Zea mays var. sachirata L.) cv. Contibrasil were transplanted to pots containing 7kg of S and size pure quartz. During the first 5 days the plants received only water. Treatments were started 18 days after germination and consisted of: complete solution (all nutrients): -N, -P, -K, -Ca, -Mg, -S, -B, -Zn. Solutions were supplied to the plants through percolation. Plants were collected as soon as the symptoms appeared and divided into: new leaves, old leaves, stem, tassel, straw, and cob. All the material was dried at 80°C for several days and analysed for nutrient content by laboratory conventional methods. The authors concluded that: a) omission of any of the elements reduce plant growth; b) clear cut symptoms were obtained for all nutrients; c) levels in the new leaves both healthy and diseased were: N% 1.29-0.72; P% 0.17-0.03; K% 1.33-0.15; Ca% 0.90-0.74; Mg% 0.36-0.03; S% 0.20-0.08; B ppm 39-21; Zn ppm 3-4; and d) levels in the old leaves, both healthy and diseased, were: N% 0.54-0.48; P% 0.05-0.02; K% 1.12-0.08; Ca% 1.05-0.70; Mg% 0.54-0.03; S% 0.13-0.10; B ppm 58-25; Zn ppm 2-10.
sweet corn; malnutrition symptoms; macronutrients; boron and zinc