Depresso por endogamia em populaes de milho-pipoca

Eight popcorn populations (CMS-42, CMS-43, Zelia, RS-20, Catedral, Zaeli, UEM-J1 and UEM-M2) were evaluated aiming at obtaintion of estimates of inbreeding depression and average genetic components and to compare these estimates to each genetic group. Each trial was carried out with plots in randomized complete block design with three replications in split-plot experiment, in which the plots were the inbreeding levels (S1 and S0) and in the sub-plots the populations in two years (1998/99 and 1999/00). The characteristics grain yield and popping expansion were evaluated. The GARDNER methodology (1965) was used for obtaining the estimates of average genetic components. It was observed lower values of inbreeding depression and predominance of additive effects for popping expansion in relation to yield. The values of inbreeding depression for grain yield were higher in the composite than in bath, improved and not improved varieties. Using these populations the probability of success in the obtaining vigorous and high popping expansion inbred lines is low.

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