Seed Treatment Techniques to Improve Germination of Wild Asparagus (Asparagus acutifolius L.), a Potential New Crop

Abstract

Pre-sowing seed treatment techniques of stratification and scarification were used in order to find the most appropriate method to overcome dormancy of wild asparagus (Asparagus acutifolius L.) seeds. An indoor and an outdoor experiment were carried out at the Agricultural University of Athens. For the indoor experiment, the pre-sowing treatments of stratification (fresh and stratified seeds) and scarification (non-scarified, mechanical scarification and chemical scarification with sulfuric acid) were used as the main treatments, and three different temperatures (15, 20 and 25 °C) as sub-treatments. For the outdoor experiment, there were only the treatments of stratification and scarification. The stratification of asparagus seeds was found to have a positive effect on germination and vigor indices compared to non-stratified (fresh) seeds. The highest germination percentage, vigor index I and II were recorded with the stratified seeds that had been mechanically scarified in both indoor and outdoor conditions. The results indicate that just the scarification cannot improve germination of fresh collected seeds of wild asparagus. Stratification increased the germination percentage from 2.7-6.6% to 45.1-75.3%. The mechanical and the chemical scarification had a positive effect on the root length compared to the non-scarified seeds that have been stratified. These pre-sowing treatments can increase the germination percentage and produce vigorous seedlings that can be used to establish plantations of this potential new crop.