Germination Ecology of Catchfly (Silene conoidea) Seeds of Different Colors

ABSTRACT - Catchfly ( Silene conoidea ), an annual herb, is usually recognized asan emerging weed species in Eurasia and North America. The presence of somaticseed polymorphism might aid in the adaptation of this weed in different climaticconditions. We conducted laboratory and greenhouse experiments to study theseed polymorphism and influence of various environmental factors like temperature,salt stress, osmotic stress and burial depth on the germination and emergencecharacteristics of catchfly. Optimum germination of seeds of all colors was recordedat a temperature of 15 o C. Germination of catchfly seeds of all colors followeddecreasing trend as NaCl concentration increased from 50 mM to 200 mM. Seedgermination was maximum (87-96%) at 0 MPa but gradually decreased to 40% asosmotic stress increases up to -0.4 MPa and completely inhibited at 0.6 MPa of allseed colors. A slight increase (from 60 to 95%) in the germination of seeds of blackand dark brown colors was observed when seeding depth increased from 0 to 2 cmbut decreased when seeding depth increased from 2 to 4 cm in seeds of all colors.There was no emergence of catchfly at seeding depth of 6 cm or greater. Our resultsconcluded that catchfly seeds have the potential to germinate and emerge in variousenvironmental conditions, but germination/emergence percentage of seeds of allcolors will be different in different environmental conditions. Soil amendmentsincluding deep ploughing may aid for the successful management of this weed incultivated areas.