Estimates of Heritability for Oil and Protein Content of Grain in Confectionary Sunflower Landraces under Different Levels of Irrigations

In order to investigate the genetic diversity and the heritability of oil and protein content of grain in confectionary sunflower under different water availability, 56 local populations were studied in three separate experiments with rectangular lattice design (7×8) with two replications at Agricultural Research Center of West-Azerbaijan province, Urmia, Iran in 2012. Water treatments were well-watered, moderate and severe water stress conditions so that irrigation was applied after 50%, 70% and 90% depletion of available water, respectively. The results showed that in all three different water treatment conditions, heritability of oil and protein percentage was more in comparion with other traits. In well-watered conditions, the heritability was between 0.77 for grain protein yield and 0.99 for oil and protein percentage. In moderate drought stress conditions, the maximum and minimum heritability was related to oil and protein percentage (0.99) and achene diameter (0.66), respectively. In severe drought stress conditions, the heritability varied between 0.85 for achene diameter 0.99 to for oil and protein percentage. In three different environments of Irrigation, the maximum genetic variation and minimum environmental variance of traits was obtained by grain oil and protein percentage. In all three irrigation conditions, the most phenotypic, genetic and environmental variance was associated with grain protein yield trait.