Pericarp splitting after aerated water soak can be used as an indicator of red oak seed quality

Abstract

Two studies were conducted to determine if pericarp splitting following an aerated water soak treatment can be used as an indicator of red oak (Quercusrubra L.) seed quality in seeds subjected or not subjected to cold stratification. In the first study, stratified red oak acorns from three open-pollinated half-sib families were treated with a 10-day aerated soak in tap water (aerated water soak treatment) and grouped into acorns with split and unsplit pericarps before conducting germination tests. Acorns stored at 2 °C during the aerated water soak treatment served as a control. Treated acorns with split pericarps had significantly greater germination capacity and uniformity than treated acorns without split pericarps. In the second study, acorns from four half-sib families were either given the aerated water soak treatment or not in October (unstratified) and in February (stratified), and a germination test was conducted. Pericarp splitting and germination were poor in unstratified seeds and high in stratified seeds. Correlations between percentage of pericarp splitting after an October aerated water soak treatment and germination completeness and uniformity in a February test were not significant. For stratified red oak seed, the aerated water soak treatment offers a fast (results can be obtained in 10 days rather than 14 to 28 days) and simple alternative to present germination tests. Also, the presence of a split pericarp following an aerated water soak treatment is a nondestructive method for identifying high-quality seed before sowing. The aerated water soak treatment is unsatisfactory for determining seed quality in unstratified red oak seed.