EFFICIENCY OF SELECTION IN THE EARLY CLON AL GENERATIONS OF POTATO (SOLANUM-TUBEROSUM L)

Selection in the early clonal generations of potato is routinely perfo rmed in breeding programs but its efficiency is poor due to being base d on visual preference. This study investigates the feasibility of usi ng plant tuber yield and its components number of tubers per plant and average tuber weight as selection criteria in the first generations. One hundred and eighteen open pollinated clones from cultivars Delta, Serrana, Omega, Mirka, Atlantic, Apua, and Radosa were evaluated in fi eld trials in the seedling (S), and in the first (C-1) and second (C-2 ) clonal generations. The coefficients of heritability and correlation s between generations were low, showing the limited success for select ion in the early generations. The strong influence of non-genetic fact ors in clonal performance, specially if a restricted number of plants per clone is evaluated in a trial without replication, as is usually d one in the early clonal generation of potato breeding programs is disc ussed.