Desnutrição de macronutrientes em plantas de Algaroba

Abstract

In order to obtain a clear picture of the macronutrients deficiencies, the dry matter production of plants submitted to deficiencies, and the levels of the macronutrients in the new ar1d old leaves, seeds of Prosopis juliflora were put to germination in a subtracts of sand and vermiculite (1+1). When the seedlings were 10 cm height, they were transferred to pots containing 7 kg of quartz and irrigated several times a day with nutrients solutions containing all elements and with the omission of N, P, K, Ca, Mg and S. When the malnutrition symptoms appeared, the plants were collected and separated into new leaves, old leaves and "stem + branches". The material was dried at 75°C and analyzed for the elements. The authors concluded that: 1) The omission of the macronutrients affected the growth of the plants (dry matter) in the following order: N > K > P > Mg > Ca > S all elements; 2) The visual symptoms were unclear; 3) The levels of the elements in the new and old leaves in the presence of all elements were: N% 2.59-1.90; P% 0.23-0.14; K% 1.93-2.04; Ca% 0.45-0.64; Mg% 0.49-0.63; S%0.20-0.21; 4) The levels of the elements in the new and old leaves in plants submitted to desnutrition were: N% 1.80-1.80; P% 0.14- 0.14; K%0.97-0.41; Ca%0.45-0.64; Mg%0.22-0.24 and S%0.09-0.09.