Source: CropBiotech Update

Argentina sunflowers sustain yield increase

A study that analyzed 20 years of research data showed that the oil yield of commercial sunflowers in central Argentina has been continuous. From 1983 to 2005, there was a genetic gain of 11.9 kg per hectare per year, for oil yield. This increase was attributed to plant breeding activities that produced varieties with biotic stress resistance and yielding ability in favorable environments. Sunflower production in Argentina started in the 1930s with open-pollinated varieties, then with hybrids in the early 1970s.

The study, conducted by Abelardo de la Vega and colleagues, noted a slowdown in the progress of yield improvement in the last ten years, from 1995–2005. However, they have attributed this to breeding activities which focused on grain-oil concentration during that period. The researchers have determined that sunflower germplasm pools still have substantial genetic variability that can be exploited to sustain yield improvement until 2010.

Abstract of the report with links to the full article for subscribers: http://dx.doi.org/10.1016/j.fcr.2006.05.012.

Field Crops Research
Volume 100, Issue 1 , 4 January 2007, Pages 61-72

Progress over 20 years of sunflower breeding in central Argentina
Abelardo J. de la Vega (a), Ian H. DeLacy (b), and Scott C. Chapman (c)
(a) Advanta Semillas S.A.I.C., Ruta Nac. 33 Km 636, C.C. 559, 2600 Venado Tuerto, Argentina
(b) School of Land and Food Sciences and A.C.P.F.G., The University of Queensland, Brisbane, Qld 4072, Australia
(c) CSIRO Plant Industry, Queensland Bioscience Precinct, 306 Carmody Rd., St. Lucia, Qld 4067, Australia

ABSTRACT

This paper applies linear mixed model analysis to 122 on-farm trials of commercial and near-commercial sunflower (Helianthus annuus L.) hybrids grown over 15 years in 32 locations of central Argentina to quantify increases in oil yield and to determine the contributions of change in both biotic stress resistance and yielding ability in favourable environments. The best linear unbiased predictors (BLUPs) from this analysis can be regarded as measures of ‘relative peak performance’ of hybrids in environments for which they were selected, and are a better measure of their adaptation compared to small trial sets of ‘historical’ hybrids. The BLUPs of 49 commercial hybrids released between 1983 and 2005 showed a genetic gain for oil yield of 11.9 kg ha⁻¹ yr⁻¹. Special purpose hybrids that were converted for single traits or that were developed for low-technology markets lagged by 5–15 years in terms of genetic gain. Genetic gains came about due to both an increase in the number of hybrids with resistance to the major biotic stress (Verticillium dahliae Klebahn) and a genetic gain in oil yield of 14.4 kg ha⁻¹ yr⁻¹ within these hybrids. Based on the data and the estimated time lag between commercial release and peak use, the improvement in oil and grain yield of conventional hybrids in central Argentina will be sustained until at least 2010, with evidence that the new germplasm pools still have substantial genetic variance to be exploited.

Source: http://dx.doi.org/10.1016/j.fcr.2006.05.012