The study of soybean (Glycine max) biometry and phenology can detect characteristics that interfere with yield, and quantitative plant development may vary according to the interaction between the genotype and the environment, and in different phenological development stages of the plant. This study evaluated the quantitative changes and phenological development caused by sowing date and their relation to grain yield of four contrasting soybean cultivars. The experimental design was a split plot with three replications, being the sowing date allocated to plots and the cultivars to subplot. The height of plants, diameter and number of nodes of the main stem, number of the branches, and leaf area index (LAI) were determined at four growth stages: V4, V9, R2 and R5.3, and the number and dry matter (DM) of the nodules at R5.3 growth stage. There was a reduction of growth in all cultivars with delayed sowing dates; however, the cultivar of determined growth habit showed to be less responsive to different sowing dates than the other cultivars. The DM of nodules was higher when plants were sown in October, and the cultivar with larger LAI obtained more DM of nodules than the others cultivars. The definition of the final quantitative characteristic of the plants occurred after the growth stage V9, and the LAI was the character at R5.3 with highest correlation with grain yield.

The present study, was performed in Guarapuava, Paraná, with the objective of evaluating the development and productivity of lettuce plants (Lactuca sativa L.) cultivar Americana in soil with different Al 3+ saturation, grown in greenhouse. The height of plants, main root length, circumference head, fresh matter of leaves and roots, dry matter of leaves and roots were evaluated, during the cycle of crop and at the harvest. In the harvest also was analyzed the number of leaves per plant. The used experiment design was completely randomized with four repetitions. The saturations of Al 3+ used were 0, 20, 40 and 60%. The root system of the lettuce Americana is very susceptible to the toxic effects of aluminum, tolerating on maximum 6.0% of saturation so it does not present damage length loss and/or mass accumulation. The production of the aerial part of the Americana lettuce showed negative linear answer to the increase of saturation for Al +3 , not being tolerant to the presence of the free form of this element in the soil. , cultivada em ambiente protegido. Foram avaliadas a altura de plantas, comprimento da raiz principal, circunferência da cabeça, massa fresca de folhas e de raiz, massa seca de folhas e de raiz, durante o ciclo da cultura e na colheita. Na colheita também foi analisado o número de folhas por planta. O delineamento experimental utilizado foi inteiramente casualizado com quatro repetições. As saturações de Al 3+ utilizadas foram 0, 20, 40 e 60%. O sistema radicular da alface Americana é muito suscetível aos efeitos tóxicos do alumínio, tolerando no máximo 6,0% de saturação para que não apresente perda de comprimento e/ ou acúmulo de massa. A produção da parte aérea da alface Americana mostrou resposta linear negativa ao aumento da saturação por Al Keywords ResumenEste estudio se realizó en Guarapuava, Paraná, para evaluar el crecimiento y rendimiento de las plantas de lechuga (Lactuca sativa L.) cultivar americana el suelo con diferentes saturaciones de Al 3+, cultivada en invernadero. Se evaluó la altura de las plantas, longitud de la raíz principal, el perímetro de la cabeza, masa fresca de hojas y de la raíz, masa seca de hojas