Nutrição mineral de hortaliças: XXII. diferenças nutricionais entre as variedades de pimentão (Capsicum annuum L.), Avelar e Ikeda

anglais. The presente work, was carried out in order to study: a) the effect of omission and presence of the macronutrients on the growth of the plants; b) the amounts of macronutrients, absorbed during the growth of the plants; c) the sensibility to nutritional deficiences. Young sweet pepper plants of varieties Avelar and Ikeda were grown in pots containing pure quartz. Twice a day, they were irrigated by percolation with nutrient solution. The treatments were: complete solution and deficient solutions, in which each one of the macronutrients was omitted (HOAGLAND & ARNON, 1950). When the malnutrition symptoms appeared, the plants were harvested and their dry matter was analysed chemically. The absorption of macronutrients was studied with the plants of both varieties, cultivated under field conditions. Periodically, plants were harvested and analysed for N, P, K, Ca, Mg and S. Conclusions: 1 - both of the varieties are resistent to blossom-end rot; 2 - the variety Avelar has a greater demand in macronutrients, on the begining of fruitage, than the variety Ikeda; 3 - the variety Avelar is more sensibile to deficiencies of the macronutrients, than the variety Ikeda; 4 - the initial rate of growth of the sweet pepper during the first 75 days, in rather slow; 5 - new experiments are necessary to study times of application of N; 6 - there's no significant difference between the varieties, in the total nutrients absorbed on the end of the plant cycle; 7 - one ha of sweet plants (31,250) remove and export the following quantities in nutrients:

portugais. O presente trabalho teve como objetivos, estudar comparativamente aspectos da nutrição mineral das variedades de pimentão, Avelar e Ikeda, no que concerne: a) ao efeito da omissão e presença dos macronutrientes, no crescimento das plantas; b) às quantidades de macronutrientes absorvidos durante o crescimento das plantas; c) à sensibilidade a deficiências minerais. Plantas de pimentão, das variedades Avelar e Ikeda foram cultivadas em vaso contendo silica. Aos sessenta dias de idade foram submetidas aos tratamentos, que constaram do cultivo de plantas em solução nutritiva completa e omitindo um macronutriente por vez. As mesmas variedades foram também cultivadas em condições de campo, coletando-se amostras de plantas periodicamente. Obtidos materiais de ambos os ensaios, processaram-se as análises químicas. A var. Avelar mostra-se mais exigente em nutrientes, no período inicial de frutificação e é mais sensível a carências nutricionais que a var. Ikeda.