This post is not really meant to be read start to finish. The intent is that it will be picked up by search engines so that breeders and researchers working with these accessions in the future can find this information.
We use accessions supplied by the USDA in some of our breeding work. This report covers accessions of wild potatoes, supplied as true potato seeds. We’re reporting germination percent after 30 days and speed of germination relative to S. tuberosum. Seeds that had their first germination at least 3 days earlier than S. tuberosum are noted as fast and those that had their first germination at least 6 days later than S. tuberosum (when S. tuberosum germ had reached 50%) are noted as slow. Accessions that germinated after the initial 30 day evaluation period are noted as very slow.
All seeds were started in sterile potting soil in individual cells. Either 25 or 50 seeds were sown. The seed starting room was heated to 65 degrees during the day and allowed to fall as low as 50 degrees at night. Seeds were not treated with GA3.
Overall, germination was low compared to fresh seed of S. tuberosum, which reached 90% germination in 16 days. 19 accessions (18%) failed to germinate at all, although I am maintaining those cells in the hope that they might eventually germinate. Where more than one accession was grown, results were fairly uniform by species. That might indicate that our starting conditions weren’t in the right range for some of the species that didn’t germinate. Bamberg (2018) reported that alternating temperatures inhibit germination in some species. I wish that paper had been published a few months earlier! We will retry the low or non germinating accessions for which we still have some seed at constant temperature to see if they do better.
Thanks to the USDA Potato Introduction Station for maintaining and providing these accessions.
|Species||PI Number||Germination %||Germination Time|
|S. burkartii||568985||16||Slow to very slow|
|S. dolichocremastrum||498234||20||Very slow|
|S. flahaultii||498166||8||Slow to very slow|
|S. morelliforme||619119||4||Very slow|
|S. raphanifolium||210048||36||Slow to very slow|
|S. schenkii||498250||40||Slow to very slow|
|S. sogarandinum||230510||16||Very slow|
|S. x aemulans||275132||30||Slow|
|S. x aemulans||500018||22||Slow|
|S. x blanco-galdosii||498214||0|
|S. x doddsii||442690||28|
|S. x michoacanum||653799||56||Fast|
|S. x rechei||558227||12|