Factor affecting seed germination on common teasel (Dipsacus fullonum L.) in Buenos Aires province, Argentina.

BENTIVEGNA D. J.; TUCAT G; FERNÁNDEZ O.A.

Mar del Plata

Conferencia; 2nd World Conference on Biological Invasions and Ecosystem Functioning; 2011

Grupo de Investigación y Educación en Temas Ambientales(GrIETA)

Dipsacus fullonum is an invasive weed in Buenos Aires province affecting natural pastures, consevation areas , and railroad. Reproduction is only by seed. Research was conducted to determine the effect of temperature, osmotic potential, pH, and salinity on seed germination. One hundred seeds were collocated in Petry dishes (five repetitions) and put in growth chamber for each research. Sixten temperatures were evaluated from 6 to 36 C. Solution of osmotic potential (0, -0.2, -0.4, -0.6, -0.8, and -1 MP) and pH (3, 4, 5, 6, 7, 8, 9, 10, 11, 12) were prepared dissolving Polyethylene glycol 6000 and HCL or Na(OH) in destillate water, respectively. Salinity was determined with different concentration of NaCL solution ( 0 ,10, 20, 40, 80, ,160, 320, 640 nM). Optimal temperature of germination was 22 C. There was no germination below 6 C and above 36 C. The osmotic potential required for 50% of inhibition of the maximm germination was -0.479 MP. Germination was completed inhibited at -0.8 MP. There is slight effect of the pH in seed germination; however, all treatments resulted in high germination  (>90%). Germination was greater that 90% up to 100 nM and inhibition of 50% of maximum germination was reached at 319 nM. Germination was inhibited at 640nm. Seed germination of D. fullonum showed wide range of temperature, slight effect by the pH, with elevate threshold to water stress and salinity. All these germination characteristics allow to invading places with variable ecological features in the Buenos Aires province.