M. Telli et al., STRATIFIED MASS SELECTION IN SUNFLOWER IN DIFFERENT ENVIRONMENTAL-CONDITIONS, Pesquisa agropecuaria brasileira, 31(3), 1996, pp. 201-208
An open pollinated cultivar of sunflower (Helianthus annuus L.) was ma
ss selected in two successive growing seasons with the main objective
of evaluating the genetic progress obtained with two cicles of selecti
on per year involving one cicle in stress conditions. Selection was pe
rformed in the favorable environment only (spring), where sunflower is
grown commercially, in the unfavorable environment only (summer), or
continuously in both environments. The selection criteria were reducti
on of cicle and plant height and improvement of achene yield, with mor
e emphasis given to cicle reduction. Tested in the favorable environme
nt, spring selections were superior to Summer selections. The continuo
us selection was superior to both others in cicle and plant height red
uction, but resulted in higher yield reductions.