Heterosis expression toward technological parameters in F1 onion hybrids for drying

The suitability of newly developed F-1 onion (Allium cepa L.) hybrids for drying was evaluated in 3-year experiment by the expression of the heterosis effect toward the time for reaching to the minimal equilibrium moisture content during the drying process. Lines, varieties and F-1 onion hybrids of three types (hot, semi-hot and sweet) with yellow envelope flakes and different morphological characteristics were used. The drying time for the investigated variants ranged between 70 and 180 minutes. The bulbs of hybrid Liaskovski sterile x Jubilei 50 (LA x J50) F-1 were dried most rapidly. The hypothetical heterosis varied from -17.65% to 46.67%. Heterosis manifestations concerning drying time of onion bulbs were expressed but they have not economic importance. Therefore the heterosis breeding is not the way for increasing the suitability of onion for drying. Systematic investigations on the initial plant material before including in the hybridization in order to search parental components with optimal values of the drying parameters have to be on the focus.