|Common Name(s)||Papa cimarrona, papa del monte (Facciola 1998)|
|Synonyms||S. alpicum, S. semidemissum, S. utile|
|Self-compatible||Yes (Pushkarnath 1942)|
|Cytoplasm Type||D (Hosaka 2014)|
||Lindley: J. Hort. Soc. London 3: 70, fig. pg. 69. 1848.|
Solanum demissum (demissum meaning “low lying”) is a widespread species in Mexico, particularly densely in central Mexico, and reaching south into Guatemala. Plants reach about 18 inches tall, although many take on a much more compact or rosette form. Flowers violet to purple. Stolons long, two feet or more. Tubers are white to tan, round to compressed. Tuber size often reaches two to three inches.
This species is more closely related to S. acaule and S. albicans than to other Mexican species, which is quite interesting given the very long distance between the natural ranges of those species.
Both tubers and cooked fruits are reportedly consumed in Mexico. Glycoalkaloids can be rather high in this species so I recommend that you refrain from eating large amounts. Because there are almost no published measurements of glycoalkaloids in potato berries, I would also be very careful with those. The people who traditionally eat this species may know more than we do about how and when it can be done safely.
This species was long thought to be an allopolyploid, bearing both the A and B genomes. More recent work has shown that it is an autopolyploid, with only the A genome (Rodriguez 2009). The chromosomes of this species form three sets of bivalents (He 2018).
Subramanian (2017) found that at least some accessions of this species have unusually high dry matter content.
S. demissum is probably the female parent of the hybrid species S. x edinense.
To date, eleven discrete resistance genes to late blight have been introduced to S. tuberosum from S. demissum. The major late blight resistance gene in this species is R1.
|Condition||Type||Level of Resistance||Source|
|Colorado Potato Beetle||Invertebrate||Somewhat resistant||Machida-Hirano 2015|
|Drought||Abiotic||Somewhat resistant||Machida-Hirano 2015|
|Early Blight||Fungus||Somewhat resistant||Jansky 2008|
|Frost||Abiotic||Somewhat resistant||Machida-Hirano 2015|
|Golden nematode (G. rostochiensis)||Invertebrate||Somewhat resistant||Castelli 2003|
|Late Blight||Fungus||Resistant||Gonzales 2002, Bachmann-Pfabe 2019|
|Potato Cyst Nematode (G. pallida)||Invertebrate||Somewhat resistant||Castelli 2003, Bachmann-Pfabe 2019|
|Potato Leaf Roll Virus||Virus||Somewhat resistant||Machida-Hirano 2015|
|Potato Virus X||Virus||Somewhat resistant||Machida-Hirano 2015|
|Potato Virus Y||Virus||Resistant||Machida-Hirano 2015|
|Potato Virus Y||Virus||Not resistant||Cai 2011|
|Root Knot Nematode||Invertebrate||Somewhat resistant||Machida-Hirano 2015|
|Soft Rot / Blackleg||Bacterium||Somewhat resistant||Chung 2011, Machida-Hirano 2015|
|Wart||Fungus||Somewhat resistant||Machida-Hirano 2015|
Sarquis (2000) measured the total glycoalkaloid content of tubers of an accession of this species at 70.4 mg / 100g, a level 3.5 times the safety limit. The tubers that I have tasted were not terribly bitter and I can imagine making edible selections of this species without too much trouble.
I have found S. demissum difficult to germinate, with often low germination percentage and a prolonged germination period.
Towill (1983) found that seeds of this species stored at 1 to 3 degrees C germinated at 60 to 98% after 20 years.
This species typically has four to five months of dormancy.
This species has been included in the pedigrees of at least 58 hybrid cultivars of Solanum tuberosum. It was particularly popular in pre-WW2 German potato breeding and the resulting crosses were known as the “W races.”
Crosses with S. tuberosum
|S. demissum||S. tuberosum||Moderate||High||Jackson (1999)|
|S. tuberosum||S. demissum||Low||Moderate||Jackson (1999)|
Crosses with other species
|S. demissum||S. chacoense||Yes||Yes||Reddick 1939|