Influence of photoperiod and air temperature on the growth, flowering and maturation of soybean (Glycine max (L.) Merrill)

Abstract

ABSTRACT:With the purpose to evaluate the effect of short (12 hours) and long (13 and 14 hours) photoperiods and air temperature regimes (winter and summer growing seasons) on soybean behaviour, greenhouse experiments were installed at the Federal University of Viçosa, Brasil, from June 1984 to December 1985. In each experiment, under a completely randomized design with 12 treatments (soybean cultivars) and eight replicates: duration of vegetative period from emergency to stage Rl or flowering (DVP, in days); plant height (PH, m); number of nodes per plant at stage Rl (NNP); and duration of soybean cycle from emergency to stage R7 or physiological maturity point (DC, days), were evaluated. The results permit to conclude that: the vegetative period from emergency to flowering and the juvenile period are significantly affected by the photoperiod and temperature differences; shorter photoperiods or higher temperatures anticipate flowering; longer photoperiods under the same temperature regime or higher temperature under the same photoperiod regime result in higher plants. Keywords: phenology, plant height, photoperiodism INFLUÊNCIA DO FOTOPERÍODO E DA TEMPERATURA DO AR NO CRESCIMENTO, FLORAÇÃO E MATURAÇÃO DA SOJA (Glycine max (L.) Merrill)RESUMO: Experimentos em casa-de-vegetacão visando estudar o comportamento de cultivares de soja perante fotoperíodo curto (12 horas) e longo (13 e 14 horas) e na presença de temperaturas variáveis em função de diferentes épocas de semeadura, foram instalados na Universidade Federal de Viçosa, MG, Brasil, durante o período de junho de 1984 a dezembro de 1985. Delineado inteiramente ao acaso, cada experimento contou com doze cultivares de soja repetidos oito vezes por época. Avaliaram-se as seguintes características: duração do subperíodo emergência -inicio do florescimento, altura de planta e número de nós vegetativos formados por planta e duração do subperíodo emergencia -maturidade fisiológica. Concluiu-se que a fase fenológica da soja compreendida entre a emergência e o inicio do florescimento é significativamente influenciada pelas variações do fotoperíodo e da temperatura do ar; fotoperíodo e temperatura interferem com a duração fenológica do período juvenil da soja e acréscimos de fotoperíodo e de temperatura antecipam o florescimento da soja e aumentam a altura de suas plantas. Descritores: fenología, altura de planta, fotoperiodismo

Sowing Dates and Soybean Cultivars Influence Seed Yield, Oil and Protein Contents in Subtropical Environment

“…The number of nodes on the main stem is greater with the longer is the photoperiod (Câmara et al, 1997;Kantolic & Slafer, 2007). This affirmation explains the results of this study, which the plants sowed in October and November, had longer photoperiod during their growth, and more nodes at main steam.…”

Fenologia De Espécies Arbóreas Em Região Urbana, Taubaté, Sp

“…O início do ano hidrológico se dá em agosto e o término em julho do ano seguinte, com 1.335 mm de precipitação anual total, 42% dessa ocorre nos meses de dezembro a fevereiro (HORIKOSHI;FISCH, 2007). O período de estiagem, de 15 a 20 dias, ocorre na época do inverno (FISCH, 1999 (COSTA et al, 2007;PEREIRA-SILVA et al, 2007;CARDOSO, 2009 CAMARA et al, 1997;FERRAZ et al, 1999;TALORA;MORELLATO, 2000;FISCH et al, 2000;SANTOS, 2007;MORELLATO, 2008;PEREIRA et al, 2008;CARDOSO, 2009)…”

Yield Components and Biomass Partition in Soybean: Climate Change Vision

“…The artificial enrichment of the growth environment of soybean plants with CO 2 , O 3 and temperatures according to the forecasts on the atmospheric composition for the year 2100, can allow to know the morphophysiological responses in several levels of the plant organization, long before environmental changes occur.The study of the morphophysiological mechanisms of response of soybean plants to the ecological environment where they develop and produce grains, constitutes the basis of soybean ecophysiology.The factors of the climate (temperature, radiation, rainfall, wind and atmospheric pressure, among others), plus the physicochemical properties of the soil and the cultural practices applied in the field continuously influence the performance of the community of soya plants from germination to the senescence of the plants. Throughout the different phenological stages, the expression of stage-tissue genes defines the course of the development of the plant, the formation of the biomass and its components (roots, stems, leaves, flowers, fruits and seeds) respond simultaneously and hierarchically with the objective of completing its biological cycle and producing seeds for the perpetuation of the plant, and that for humanity represents the basis of agricultural production.The most important climatic factors for the development and production of soybean cultivars are temperature and photoperiod and their interactions, plus other favorable/limiting factors and resources such as precipitation variability, appropriate supply of nutrients and elimination of inter-and intraspecific competition, which also interact to determine the production of soybeans in a given region [3,4].The temperature is directly related to the speed of the metabolic rates and the chronological duration of the different phenological stages of the crop, and in the case of floral induction, in interaction with the photoperiod in plants responsive to the duration of the night to flower. The photothermal influence in the growth stages can be predicted by unit heats method.…”

“…The most important climatic factors for the development and production of soybean cultivars are temperature and photoperiod and their interactions, plus other favorable/limiting factors and resources such as precipitation variability, appropriate supply of nutrients and elimination of inter-and intraspecific competition, which also interact to determine the production of soybeans in a given region [3,4].…”