Mineral nutrition of vegetables crops: LXXXVI. nutrient concentration in lettuce (Lactuca sativa L.) c.v. grand rapids, in direct seeding and for cutting

Com o objetivo de determinar a concentração e acúmulo de nutrientes durante as fases de desenvolvimento da alface Grand Rapids, cultura de corte, foi instalado um experimento na área experimental da ESALQ e amostras foram coletadas aos 20, 30, 40 e 50 dias da semeadura, em canteiros com alto teor de matéria orgânica e solo Latossolo Vermelho Escuro Orto série Luiz de Queiroz. Aos 50 dias após a semeadura o teor de nutrientes foi: N-3,35% e 1,76%, P-0,46% e 0,5%, K-4,49% e 5,92% , Ca-0,92% e 0,58%, Mg-0,32% e 0,23%, S-0,23% e 0,25%, B-43ppm e 62ppm , Cu-21ppm e 22 ppm, Mn-71ppm e 39ppm , Zn-98ppm e 103ppm e Fe-513ppm e 1.100ppm, na parte aérea a raiz, respectivamente. Um are dessa cultura extrai: N-1,44kg, P-0,23kg , Ca-0,40kg, Mg-0,15kg, S-0,11kg, B-2,10g, Cu-0,97g, Mn-3,07g, Zn-4,52g. Direct seeding lettuce crop for cutting was analysed for macro-and micronutrients extraction during growth period. The cultivar used was Grand Rapids and the soil was a Dark Red Latosol, Luiz de Queiroz series. The nutrient levels in 50-day old plants were : 3.35% and 1.76% N, 0.46% and 0.5% P, 4.40% and 5.92% K , 0.92% and 0.58% Ca, 0.32 and 0.23% Mg, 0.23% and 0.25% S, 43 ppm and 62 ppm B, 21 ppm and 22 ppm Cu, 71 ppm and 39 ppm Mn, 98 ppm and 103 ppm Zn, 513 ppm and 1.100 ppm Fe, in upperground and roots, respectively. A 100 m² area of crop extracts: 1.44 kg N, 0.23 kg P, 0.40 g Ca, 2.15 kg K, 0.15 kg Mg, 0.11 kg S, 2.10 g B, 0.97 g Cu, 3.7 g Mn, 4.52 g Zn.