Hybrid breeding of Pampa-cytoplasmic triticale based on crosses with rye.

Abstract

The first series of field experiments with triticale F1 hybrids from 2009 confirmed usefulness of the rye 'Pampa' cytoplasmic system of mass crossing control in hexaploid (2n = 42 = AABBRR) winter triticale. The level of fertility restoration in 30 F1 hybrids varied within a range of 35.1% - 91.3%. However, the top F1 yield has not exceeded 92% of the check cultivar 'Moderato'. In the next series of field experiments with four winter F1 hybrids from 2012 the best yield reached 102% of the 'Moderato' standard and the fertility restoration index ranged between 16.7% and 100%. The top yielding F1 combination was produced using a male line derived from a cross with a restorer line from rye hybrid breeding. It supports the idea of using rye hybrid breeding as a source of variation in hybrid breeding of triticale. The advanced rye lines, representing well established complementary gene pools, show not only high potential for heterosis, but also high level of compensation for negative side effects of the 'Pampa' cytoplasm on plant vigor, which seems important in triticale. The gene flow from rye female and male gene pools to those of hexaploid triticale is facilitated with tetraploid triticale x diploid rye crosses. Numerous triploid F1 hybrids with relatively high fertility are produced, which are able to set seed after spontaneous pollination with hexaploid triticale.