Photoblastic and temperatures in the germination of cockscomb seeds

• Autor(a) principal: Menegaes,Janine Farias
• Data de Publicação: 2018
• Outros Autores: Barbieri,Geovana Facco, Bellé,Rogério Antônio, Nunes,Ubirajara Russi
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Ornamental Horticulture (Campinas)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S2447-536X2018000400408
• topic: Celosia argentea; Celosia cristata; ornamental seeds

ABSTRACT Germination is the result of the triggering of various processes occurred in the seed, which are influenced by the environmental conditions, especially light and temperature. In this way, the objective of the present study was to evaluate the influence of different temperatures and photoblastic on the germination of cockscomb seeds. The experiment was carried out in a completely randomized design, with a 2 × 5 factorial scheme (two lighting regimes and five temperatures), with four replicates of 50 seeds, for two species of cockscomb (Celosia argentea L. and C. cristata L.). The lighting regimes were with absence (dark continuous) and the presence of light (photoperiod of 24 h), and temperatures were constant at 15, 20, 25, 30 and 35 °C. The seed lots of the two species of cockscomb were cultivated in 2012 and stored in a cold chamber (15 °C and 40% RH), with an average moisture content of 11% and a mean germination of 98%. The results of the laboratory tests indicated that the two species of cockscomb presented fast germination in average 2.5 and 4.5 days for the regimes with presence and absence of illumination, respectively, characterizing as neutral photoblastic species. However, it was observed that the temperature is a limiting factor for the germination of the two species of cockscomb, having its optimal thermal range between 20 and 30 °C