Soybean Flowering Date: Linear and Logistic Models Based on Temperature and Photoperiod

Abstract

Temperature and photoperiod are important determinants of the time from emergence to flowering in soybean [Glycine max (L.) Merr.]. A linear and a logistic model have been developed independently for describing the development rate to flowering (a high development rate means a short time to flowering). Field experiments on Arredondo fine sand soil (loamy, siliceous hyperthermic Grossarenic Paleudult) at Gainesville, FL, during 3 yr using a range of sowing dates in each year provided data to evaluate each model. In the first 2 yr, 13 cultivars were grown from 17 sowing dates. The linear model was found to represent adequately these 2 yr of data, but the logistic model was somewhat superior for 12 of the 13 cultivars. The coefficients derived for each model from the first 2 yr of study were used to predict flowering date in the 3rd yr. Both models gave accurate predictions of flowering date, although the larger discrepancies between predictions and observations were obtained with the linear model. Assuming an adequate data base to evaluate the coefficients in each model, either model was able to predict soybean flowering date.

ABA Increased Soybean Yield by Enhancing Production of Carbohydrates and Their Allocation in Seed

“…The final weight of the seed depends on the growth rate and the duration of grain filling, and both factors are genetically determined and vary according to the environmental conditions. The duration of the reproductive period can be changed by manipulating the plant responses to the environmental factors that control its development, particularly temperature and photoperiod; these factors act simultaneously in the plants and there are evidences of their interaction (Sinclair et al, 1991;Kantolic et al, 2003). Though temperature has influence during the whole crop cycle, the photoperiod starts its regulation when the juvenile part ends.…”

Água no solo e rendimento do trigo, soja e milho associados ao El Niño Oscilação Sul

“…Para a condição potencial, eliminaram-se os algoritmos de resposta ao deficit hídrico do modelo de Sinclair (1986). As datas de término de crescimento foliar e início do enchimento de grão foram simuladas para a cultivar Bragg, com o modelo não-linear de resposta do desenvolvimento à temperatura e ao fotoperíodo propostos por Sinclair et al (1991), utilizando-se dados de um ensaio realizado no campo experimental do Departamento de Fitotecnia da UFSM, Santa Maria, RS, no ano 1983/1984, sendo que o término do crescimento foliar corresponde ao dia de estádio de desenvolvimento 1 e o início do enchimento de grãos ao dia de estádio 1,8 do modelo de Sinclair et al (1991).…”

Subperíodos fenológicos e ciclo da soja conforme grupos de maturidade e datas de semeadura

“…A data de início da floração (R1) foi simulada com o modelo não linear de resposta do desenvolvimento à temperatura do ar e com o fotoperíodo proposto por Sinclair et al (1991), com uso de diferentes coeficientes conforme o grupo de maturidade. Este modelo inicia a integração a partir da data de emergência e termina quando a taxa de desenvolvimento atinge 1,0, que corresponde à data do estádio R1.…”