Genotype by environment interaction and association of yield contributing traits in sunflower genotypes under the environmental condition of Sargodha, Pakistan

Abstract Oil content and other yield contributing metric traits are highly influenced by environmental conditions hence, the phenotype of a trait is a response of interaction between environment and genetic makeup of crop. Climate change is one of the major challenge faced by growers nowadays because it adversely affects the growth and development of sunflower and ultimately reduce oil content. Therefore, keeping in view the challenge of climate change, the present research was conducted during 2019, to evaluate the performance of 28 sunflower hybrids under normal and terminal heat stress conditions at the research farms of the College of Agriculture, University of Sargodha, Sargodha-Pakistan. Pakistan. Data were recorded on days to 100% flowering, stem girth (cm), head diameter (cm), 100-achene weight (g) and oil contents (%). Analysis of variance revealed the presence of genetic diversity among 28 hybrids for all the traits under consideration. Irrespective of traits, the mean square revealed the role of experimental error was minimum than the environment, genotype and their interaction (G × E). The environmental influence was found to be 68.94, 49.99, 53.94% for days to 100% flowering, stem girth (cm) and 100-achene weight (g), respectively. However, genotypes play a major source of variation for head diameter (cm) and oil content (%). Oil content has a significant positive correlation with traits under study. Based on mean performance under normal and terminal heat stress conditions hybrid SF-19033 and SF-19028 performed best for yield contributing traits and adoptable under the environmental conditions of Sargodha-Pakistan.