Maternal effect on response of oleic acid content to temperature in high oleic sunflower

Abstract

High oleic trait has been rarely studied in reciprocal crosses and in most of these cases the maternal effect on the content of unsaturated fatty acids has not been identified. The aims of this study are: i) to check if any maternal effect on oleic acid content is present in high oleic mutants and (ii) if maternal effect and environment conditions could modify the 90% threshold for oleic acid content. Two high oleic inbred lines with different origins were evaluated: 342mt, a selection derived by Ha 342 USDA (maintainer) and line R978 (male fertility restorer, branched) selected by University of Udine and their reciprocal crosses (R978 × 342mt and 342mt × R978). The two inbred lines respond differently to the same environmental conditions. Reciprocal hybrids showed a different accumulation pattern on the first sowing date, and they showed the same response as their female parent. There is a maternal effect in the early stages of the seed filling phase. Low temperature increased linoleic acid and decreased oleic acid at 13 DAF only in 342mt inbred line and in the 342mt × R978 hybrid. High oleic inbred lines with different genetic backgrounds respond differently to the same environmental conditions. It was determined that there was the importance of female parental line choices in breeding to obtain hybrids insensitive to environmental conditions and with a stable oleic acid content over 90%. For the first time a maternal effect on temperature response was found in high oleic sunflower.