Germination characteristics of Festuca pallescens, a Patagonian bunchgrass with reclamation potential
1995
Defosse, G.E. (Centro Nacional Patagonico (CONICET), Puerto Madryn (Argentina)) | Bertiller, M.B. | Robberecht, R.
The influence of light, temperature, and soil water content on the germination of Festuca pallescens, an important forage species native to the steppe zone of Patagonia, Argentina, was examined in the laboratory. Seeds of F. pallescens, collected along an elevational gradient from 650 to 950 m a.s.l. on the Media Luna Ranch were tested for viability and germination. In petri dishes containing top soil of the collection area 10 seeds were sown at a depth of 5 mm (dark treatment) and 10 on the soil surface (light treatment). The experiment was replicated five times at soil water contents 4, 8, and 16 % and temperatures of 5, 10, 15, and 20 deg C. Seeds were considered germinated when either the coleoptile reached 5 mm for the light treatment or when it protruded the soil surface for the dark treatment. Festuca pallescens seeds showed a viability of 99.5 %. Exposure to continuous light delayed the beginning of germination, but had no influence on total germination percentages. A soil water content of 16 % and medium to high temperatures (10, 15, and 20 deg C) rapidly promoted germination, which reached 97 % after 20 days of incubation. Germination was reduced by 40 % at a soil water content of 8 %. In all cases a 5 deg C soil temperature delayed the beginning of germination and slightly reduced its final germination percentages. Sporadic germination occurred at 4 % soil water content at 10 deg C, and none at any other temperature. Under field conditions sowing should be practised during the fall, when soil moisture and temperature are optimum for germination
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