Germination and vigor of linseed seeds under different conditions of light, temperature and water stress

Abstract

Linseed (Linum usitatissimum L.), cultivated from seeds, is one of the oldest plants domesticated by humans and is popularly used as a medicine. It can be used as the raw material to produce oil and bran because it has high lipids content, fiber and proteins. Based on the economic potential of this species and the need for more information about its physiology, the goal of this study was to analyze the effects of light, temperature and water stress on the germination and vigor of linseed seeds. In experiment I the seeds were sown on paper at constant temperatures of 15, 20, 25 and 30 ºC in the presence and absence of light. In experiment II, the seeds were placed on paper germitest soaked in solutions of polyethylene glycol (PEG 6000) at osmotic potentials corresponding to zero, -0.10, -0.20, -0.30, -0.40, -0.50 and -0.60 MPa. To evaluate the physiological potential, the following tests were made: germination, first germination count, length and dry mass of seedlings, and water stress. It was found that the highest percentages of germination and vigor occurred at a constant temperature of 20 °C, both in the presence and absence of light. The reduction of the osmotic potential of the substrate promoted a significant decrease in the germination and vigor of the linseed seeds. Osmotic potentials equal or less than -0.30 MPa were harmful to germination and there was no normal seedling development starting at -0.50 MPa. Key words: Linum usitatissimum. Physiological quality. Polyethylene glycol. ResumoA linhaça (Linum usitatissimum L.), cultivada através de sementes, é uma das plantas mais antigas domesticadas pelo homem, utilizada popularmente como medicamento. Pode ser empregada como matéria-prima na produção de óleo e farelo por possuir alto teor de lipídios, fibras e proteínas. Diante do potencial econômico da espécie e da necessidade de informações sobre sua qualidade fisiológica, objetivou-se analisar o efeito da luz, temperatura e estresse hídrico na germinação e no vigor de sementes de linhaça. No experimento I, as sementes foram semeadas sobre papel nas temperaturas constantes de 15, 20, 25 e 30 ºC na presença e ausência de luz. No experimento II, as sementes foram colocadas sobre papel embebido em soluções de polietileno glicol (PEG 6000) nos potenciais osmóticos correspondentes a zero ; -0,10; -0,20; -0,30; -0,40; -0,50; -0,60 MPa. Para avaliação do potencial fisiológico foram realizados os testes de: germinação, primeira contagem de germinação, comprimento e massa seca de plântulas e estresse hídrico. As maiores percentagens de germinação e vigor ocorreram quando da temperatura constante de 20 °C, tanto na presença quanto na ausência de luz. A redução do potencial osmótico do substrato causou decréscimo significativo na germinação e no vigor das sementes de linhaça. Potenciais osmóticos iguais ou inferiores a -0,30 MPa foram prejudiciais à germinação não havendo desenvolvimento de plântulas normais a partir de -0,50 MPa. Palavras-chave: Linum usitatissimum. Qualidade fisiológica. Polietileno glicol.

Germination of melon seeds under water and thermal stress

“…Rossetto (1997) also verified that as the water potential reduced, there was a loss of soybean seeds performance in the first germination test count. In flax seeds, Stefanello et al (2017) observed that osmotic potentials equal to or lower than -0.30 MPa were harmful to germination, and that there was no normal seedling development up from -0.50 MPa concentration.…”

Seed germination of Hesperozygis ringens (Benth.) Epling, an endemic and threatened species

“…The seeds were distributed on three sheets of paper moistened with distilled water at the proportion of 2.5 times the weight of the paper. After sowing, the plastic boxes were maintained in BOD (Biochemical Oxygen Demand) chambers at 15, 20, 25 and 30°C, in the presence and absence of light (Luz et al, 2014;Stefanello, Viana, & Neves, 2017). Counting was made every three days for 21 days.…”

“…For the absence of light, the seeds were sown in a room where the light was filtered with three green cellophane paper sheets. The germination boxes were maintained in the dark throughout the test by covering them with two sheets of aluminum foil (Stefanello et al, 2017). The evaluations for the condition without light were made in the room with filtered light.…”

Generative production and evaluation of ornamental plant potential of an endemic flax species for ecological landscape applications

“…In a study by Varga et al (2020), it was determined that L. usitatissimum seeds did not differ in germination with medium temperatures of 10 C (58%) and 20 C (59%) on the 7th day of the experiment under different salt stress conditions. Kurt and Bozkurt (2006) reported that the emergence and germination rate of L. usitatissimum seeds enhanced as the temperature increased from 10 to 30 C, and they obtained the best emergence rate (86.9%) at 30 C. Stefanello et al (2017) examined 15, 20, 25, and 30 C as germination temperature for L. usitatissimum seeds and found the best results at 20 C (79%), where 15 and 25 C (68%) showed slightly lower germination. It can be concluded that the optimum temperature required for the seed germination varies according to the species and the ecology in which the seeds of the species are collected (Fenner & Thompson, 2005;Yilmaz & Tonguç, 2013).…”

“…There are several taxonomic studies on natural Linum species found in Turkey, as well as agronomic and phylogenetic studies on commercially used Linum species (Yılmaz et al, 2011). Studies on the germination of Linum seeds focused on L. usitassisimum , which is widely used in agriculture (Bakhit & Moradi, 2017; Stefanello et al, 2017). There are no studies on the production and ornamental plant potential of other Linum species, especially endemic ones.…”