|Common Name(s)||Papa morda (Facciola 1998)|
|Ploidy||Diploid (2x), triploid (3x), tetraploid (4x)|
|Cytoplasm Type||D, W (Hosaka 2014)|
Solanum verrucosum (verrucosum means warty) is a widespread species in Mexico, where it is primarily a plant of woodlands and cloud forests. Plants about 6 to 18 inches tall. Blue flowers. Round berries.
Tubers of this species are or were occasionally eaten in Mexico, according to notes from various collecting expeditions. Correll (1962) also reports that this species was once cultivated near Geneva, Switzerland, in the hope that it would resist late blight, but eventually abandoned due to the small tuber size and late bearing.
This species is remarkable for its self-compatibility, although inbred lines do suffer from inbreeding depression as expected in diploids of this genus (Abdalla 1973). Self compatibility is rare in diploid potatoes and has only been otherwise observed in S. polyadenium and certain lines of S. chacoense that possess self-incompatibility inhibition (sli) alleles.
S. verrucosum is suspected as the progenitor of all Mexican polyploid species, based upon the presence of a mitochondrial marker (Sanetomo 2013). It is the only North American diploid species with the A genome.
|Condition||Type||Level of Resistance||Source|
|Early Blight||Fungus||Somewhat resistant||Jansky 2008|
|Golden nematode (G. rostochiensis)||Invertebrate||Not resistant||Castelli 2003|
|Late blight||Fungus||Somewhat resistant|
|Late Blight||Fungus||Somewhat resistant||Bachmann-Pfabe 2019|
|Potato Cyst Nematode (G. pallida)||Invertebrate||Not resistant||Bachmann-Pfabe 2019|
|Potato Cyst Nematode (G. pallida)||Invertebrate||Not resistant||Castelli 2003|
|Potato Virus Y||Virus||Not resistant||Cai 2011|
|Soft rot (P. carotovorum)||Bacteria||Somewhat resistant||Chung 2011|
Towill (1983) found that seeds of this species stored at 1 to 3 degrees C germinated at 100% after 27 years.
Crosses with S. tuberosum
Watanabe (1991) found that 4.1% of varieties of this species produced 2n pollen, which would be effectively tetraploid and 4EBN.
|S. tuberosum||S. verrucosum||Minimal||None||Jackson (1999)|
|S. verrucosum||S. tuberosum||None||None||Jackson (1999)|
|S. verrucosum||S. tuberosum 2x||Moderate||Moderate||High||Abdalla 1973|
Crosses with other species
Jackson (1999) found 4-11% 2n pollen for varieties of this species.
Abdalla (1973) observed that interspecies crosses in which S. verrucosum is used as the male parent are rarely successful. In addition, cytoplasmic sterility renders the majority of the progeny male sterile when S. verrucosum is used as the female parent.
|S. verrucosum||S. chacoense||High||High||Low||Abdalla 1973|
|S. verrucosum||S. chomatophilum||Low||Moderate||High||Abdalla 1973|
|S. verrucosum||S. infundibuliforme||High||High||Moderate||Abdalla 1973|
|S. verrucosum||S. raphanifolium||High||Low||High||Abdalla 1973|
|S. verrucosum||S. berthaultii (as S. tarijense)||High||Moderate||Minimal||Abdalla 1973|
|S. verrucosum||S. candolleanum (as S. canasense and S. multidissectum)||High/Moderate||Low/Moderate||Low/Moderate||Abdalla 1973|
|S. verrucosum||S. kurtzianum||High||High||High||Abdalla 1973|
|S. verrucosum||S. brevicaule (as S. leptophyes)||High||Low||Low||Abdalla 1973|
|S. verrucosum||S. microdontum (as S. gigantophyllum)||Moderate||Moderate||High||Abdalla 1973|
|S. verrucosum||S. vernei||High||Moderate||High||Abdalla 1973|