Influences of temperature and water stress on germination and establishment of Prosopis caldenia Burk

Effect of high temperatures on seed germination of Prosopis caldenia Burk

“…Controlled fires are used to control the abundance of woody species in the Caldén District . Although, some studies have evaluated the germination requirements of P. caldenia seeds (Peláez et al, 1992;Peinetti et al,1993;de Villalobos & Peláez, 2001), post-fire seed germination of this species has never been documented. This information is of critical importance in determining the dynamics of P. caldenia after fire.…”

Germination, osmotic adjustment, and antioxidant enzyme activities of gibberellin-pretreated Picea asperata seeds under water stress

“…As a solvent, water provides a fluid medium through which substrates diffuse to active sites and enzymes undergo the conformational changes necessary for catalytic activity. Research has shown that water stress strongly inhibited germination at extremely high or extremely low temperatures (Zheng et al 2004), and it may also reduce the probability of seedling establishment because of the effect of low soil water emergence, content on seedling survival, and growth of surviving seedlings (Shao et al 2008a;Villalobos and Peláez 2001).…”

Efeitos da luz e da temperatura na germinação de sementes de Syngonanthus elegantulus Ruhland, S. elegans (Bong.) Ruhland e S. venustus Silveira (Eriocaulaceae)

“…Em geral, a luz é necessária para a germinação de sementes pequenas (Thompson & Grime 1983;Bewley & Black 1994, Rosa & Ferreira 2001, cujas espécies estão associadas a ambientes abertos (Baskin & Baskin 1971) ou perturbados (Fenner 1995). A relação entre germinação e temperatura está freqüentemente associada às temperaturas a que as plantas ficam expostas durante a fase de crescimento (Baskin & Baskin 1988;Angosto & Matilla 1993;Teketay 1998a;Villalobos & Peláez 2001). A temperatura influi na velocidade e no percentual de germinação, especialmente por alterar a velocidade de absorção de água e modificar a velocidade das reações químicas que irão mobilizar ou degradar as reservas armazenadas e a síntese de várias substâncias para o crescimento das plântulas (Bewley & Black 1994), ou provocar alterações na membrana plasmática (Thompson 1974;Hendricks & Taylorson 1976).…”