Viable seed retention under field conditions by western Queensland pasture species [grasses; legumes].
1990
Silock R.G. | Smith F.T.
Newly ripened seed of buffel grass (Cenchrus ciliaris), mulga oats (Monachather paradoxa), mulga mitchell grass (Thyridolepsis mitchelliana), silky umbrella grass (Digitaria ammophila), silky glycine (Glycine canescens) and mulga nettle (Haloragis odontocarpa) was placed in nylon mesh bags in the field near Charleville, Queensland in exposed, shaded or buried situations. Buried and exposed seed of C. ciliaris lost most of its viability within 2 years without many seedlings being seen. Few exposed seeds of M. paradoxa and T. mitchelliana remained germinable after 2 years either, but many seedlings had emerged during this time. The grasses lost much of their initial seed dormancy within 3 months during a dry summer whereas the legume G. canescens retained a high level of seed dormancy for over 2 years. Hence many valuable grasses need to set seed more regularly than legumes in this environment to retain an adequate seed bank for regeneration after droughts or heavy utilization.
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