The Effect of Mother Plant Fertilization and Stratification on the Germination of True Potato Seed

Methods for diploid true potato seed (TPS) production and handing are crucial for inbred-hybrid potato breeding. This study determined the effects of mother plant nutrition on average TPS weight and germination kinetics as modeled by Gompertz curves. Additionally, it characterized germination of stratified TPS and TPS imbibed in water or gibberellic acid (GA(3)). Seeds were produced by three interspecific hybrids between diploid relatives of cultivated potato and diploid lines derived from cultivated potato. Effects of stratification on seed dormancy and germination rate were genotype-dependent. With one exception, GA(3)-treated seeds reached 50% germination as fast or faster than stratified seeds and seeds imbibed in water. Mother plant nutrition was varied by fertilizing with two nutrient solutions that differed in composition. Effects of fertilizer type on germination were modest, and 100-seed weight did not differ between fertilizer types. These findings support previous research showing that GA(3) treatment effectively promotes robust TPS germination.