| Sumario: | The maize polyembryony (PEm) is phenotypically expressed when the seed germinates
in two or more seedlings simultaneously, which in turn develops the capacity to overcome
the close competition among sisters and neighboring plants. Because of that, it is thought
that the inclusion of PEm in some new maize varieties can be useful looking for high yields
and corn grain quality as a response to the global food demand. This research is about the
PEm inheritance, the inclusion, recovery of polyembryony in segregating populations, and
exploring their performance capacity. The foundation populations were the progenies from
crosses among polyembryonic sources and inbred lines, producing several F1 groups, and
from each the proper F2, and G3 and G4 generations. The latter two were developed through
successive positive assortative matings (AM+). G3 populations were used to generate diallel
crossings, Griffing’s method 4, and part of them were evaluated in a performance assay, using
a complete block design with a split-split plot arrangement. Results supported a validation
of the inheritance model proposed for this sort of polyembryony, which states that the trait
is controlled by two independent loci, under epistatic interaction of the type "duplicate gene
action". Moreover, the arbitrarily handling of sexual reproduction in F2 plants and in G3 and
G4 generations through positive assortative matings (AM+) increased the PEm frequency
on an average up to 40 % in G4, departing from the 4.9 % in F2. Also, the performance assay
shown a yield potential of the trait. The PEm mutant might be useful in maize production.
|
|---|
Biblioteca Digital de Vanguardia