Resumo Solidago canadensis L. Cv. Tara e Delphinium elatum híbrido White Rever são flores de verão com grande potencial agronômico. O objetivo foi estabelecer a fenologia destas espécies cultivadas em estufa, assim como determinar o tipo de correlação existente entre os elementos climáticos (umidade relativa - UR, graus-dia de desenvolvimento - GDD e umidade do solo) e as variáveis de crescimento (longitude e diâmetro das hastes, peso fresco e seco). O ciclo de cultivo em S. canadensis e D. elatum, finalizou quando se tinha 30% de abertura floral, e o comprimento das hastes atingiram 118,05 e 123,74 cm, aos 94 e 77 dias, respectivamente. Ao longo do cultivo o crescimento das espécies estudadas acompanhou um patrão de curva logística, em S. canadensis os máximos valores da taxa de crescimento absoluto e a taxa de crescimento relativo foram aos 77 e 42 dias após o transplantio (DAT), respectivamente, sendo que diferença de D. elatum aconteceu aos 77 e 28 DAT. Por outro lado, no que se refere à correlação entre os elementos climáticos e as variáveis de crescimento em S. canadenis, GDD e UR correlacionaram-se de forma direta com o peso fresco e seco, diâmetro e longitude da haste, em contraste a umidade do solo que teve uma relação inversa. D. elatum evidenciou uma relação direta entre as variáveis climáticas e as variáveis de crescimento.

Abstract Solidago canadensis L. cv. Tara and Delphinium elatum, the hybrid White River are summer flowers with great agronomic potential. The goal of this study was to establish the phenology of these species grown under greenhouse conditions, as well as to determine the correlation between climatic elements (relative humidity - RH, growing degree-days for development - GDD and soil moisture - SM) with growth variables (stem length and diameter, fresh weight FW - and dry weight - DW) in S. canadensis and D. elatum. The life cycle for S. canadensis and D. elatum ended when reaching 30% of the flower opening, the stem length reached 118.05 and 123.74 cm, at 94 and 77 days, respectively. The growth of both species showed a logistic curve pattern throughout the crop cycle; S. canadensis showed maximum values for absolute growth rate (AGR) and relative growth rate (RGR) at 77 and 42 days after transplanting (DAT), respectively; in contrast to D. elatum which occurred at 77 and 28 DAT. On the other hand, for the correlation between climatic elements and growth variables in S. canadensis, the GDD and RH were directly correlated with both FW and DW, stem diameter and length, while an inverse correlation occurred for SM. D. elatum showed a direct correlation between climatic conditions and growth variables.

Resumen El objetivo de este estudio fue evaluar las características morfológicas y analizar los parámetros de crecimiento de tres cultivares híbridos de girasol (Helianthus annuus L.) para flor de corte, cultivados a campo abierto. Los cultivares híbridos Vicent Choice, Sunrich Orange y SM-373 se evaluaron en un diseño de bloques completos al azar con cuatro repeticiones. El ciclo del cultivo se finalizó al 40 % de apertura floral, a los 53 días después de la siembra para Vicent Choice, 55 días para Sunrich Orange y 63 para SM 373. La longitud del tallo promedio para los tres cultivares fue 87,36 cm. La dinámica de crecimiento de los tres cultivares se ajustó a un modelo cuadrático, en el que el tallo presentó el 50,12% del total de materia seca promedio, y el cultivar híbrido Vicent Choice obtuvo la mayor acumulación de masa seca total (42,54 g). La floración fue el estado de desarrollo con mayor eficiencia fotosintética y el índice de área foliar promedio de los tres cultivares fue de 1,33 a los 46 días después de la siembra, y Vicent Choice produjo 679 tallos exportables, lo que representó el 70,72 % del total de la producción del estudio.

Abstract The aim of this study was to evaluate the flower morphological characteristics and analyze the growth parameters for cut-flower of three sunflower hybrid cultivars (Helianthus annuus L.), coming from open field cultivation. Hybrid cultivars Vicent Choice, Sunrich Orange and SM-373 were evaluated in a Complete Block Design with four replicates. The cycle of sunflower cultivation was finalized at 40% flower opening, which occurred at 53 days after planting for Vicent Choice, 55 days for Sunrich Orange and 63 days for SM-373. In this study, the three hybrid cultivars stem length average was 87.36 cm. The growth dynamic of the three varieties was adjusted to a quadratic model, in which the stem yielded in average 50.12% of dry matter, and the Vicent Choice hybrid cultivar recorded the highest total dry matter accumulation (42.54g). Flowering was the development stage with highest photosynthetic efficacy, the average foliar area index of the three varieties was 1.33 at 46 days after planting, and Vicent Choice produced 679 exportable stems, representing 70.72% of the study's total production.