Genotype × Plantlet Age Interaction for Yield and Yield Components of Potato Minitubers in Aeroponic System

To evaluate effect of genotype and plantlet age on the yield and yield components of potato minitubers, this study was conducted under aeroponic system conditions in Ardabil agricultural and natural resources research station and Behparvar Sabalan Ardabil Company in Aradbil in Iran. Four potato genotypes including; promising clones C-397097-2, C-397081-1, cv. Agria and cv. Caesar, and three plantlet ages including; 30, 40 and 50 days were experimented as factorial arrangements in completely randomized design with three replications. The results showed that tuberization and development of minitubers was delayed in the aeroponic system. The effect of plantlet age on yield and yield components was more pronounced than genotype. The effect of plantlet age was significant (P≤0.05) on all traits. Genotype × plantlet age interaction was significant for yield and yield components, except for single minituber weight. Clone C-397081-1 of 30-day plantlet age produced the highest minitubers plant-1 (57.3 minitubers plant-1). For cv. Caesar and clone C-397097-2 of 40 days plantlet age were the best and produced on average 55.57 and 53.54 minitubers plant-1, respectively. There was no significant difference between plantlet ages of 30 and 40 days for clone C-397097-2. The cv. Agria had the best response at the plantlet age of 40 days and had on average 45.7 minitubers plant-1. Clone C- 397081-1, C-397097-2, cv. Agria and cv. Caesar produced on average 1203, 1235, 1113 and 1223 m-2, respectively. Forward stepwise regression analysis showed that the mean single minituber weight and minituber weight plant-1 was important in the selection of potato genotype for production of large number of minitubers. The mean weight of single minituber and plant height were inversely related to minituber number. In conclusion, the maximum economic minituber production for each potato genotype was affected by the plantlets age. The plantlet age between 30 and 40 days was identified as suitable for transferring potato plantlets to areoponic system.