Matryoshka: A New Floral Mutant in Wild Potato

A population of the wild potato S. stoloniferum form fendleri (PI 660270) was collected as botanical seeds in the Santa Rita Mountains near Green Valley, Arizona, USA in fall 2010. Original seeds planted for multiplication at the genebank produced two plants with extra whorls of petals, sometimes fused with anthers, and, most remarkably, successive whorls of petals, anthers and carpels nested inside the primary carpel. This mutant was named matryoshka after the similarly nested Russian dolls. Floral morphology of mutants varies. It can have nearly normal male and female fertility in some individuals. Crossing studies indicate that the mutant form is dominant. Expression of the mutant may vary over the flowering cycle of the plant, with earlier flowers appearing mutant and later flowers appearing normal. Tests for pathogens were negative. Flower development mutants are of interest considering the potential for manipulating interspecific crossability, apomixis, and virus elimination in potato, and their usefulness may be extended to the important closely-related fruit crops of tomato, pepper, and eggplant. Matryoshka could also be useful in studies of potato adaptation in the wild: For example, seedless matryoshka fruit may serve as decoys to suppress the seed-eating larvae of Odenicarena fruit flies and Cecidomyiid gall flies which are especially prevalent in the geographic area where the mutant originates.