Multi-trait Selection in Sunflower Hybrids using Double and Triple Biplots

The selection of high-yielding genotypes is especially important in sunflower. Therefore, this study was conducted to identify interrelationships between different traits and the selection of the best sunflower hybrids.

In this study, 11 new hybrids along with four cultivars Golsa, Ghasem, Shams, and Farrokh were evaluated in a randomized complete block design with four replications in the agriculture research station of Kermanshah during 2019-2020. The phonological, morphological characteristics and yield and its components including days to flowering, days to ripening, plant height, stem diameter, head diameter, seed number per head, thousand seed weight, and seed yield were measured. In this study, the methods of genotype × trait (GT) and genotype by yield × trait biplot (GYT) were used to identify interrelationships between different traits and selection of the best sunflower hybrids.

Based on polygon view of GT biplot, the genotypes No. 4 and 11 had good characteristics regarding seed yield. The vector view of GT biplot showed high correlation between seed yield with stem diameter, plant height and seed number per head. Based on average tester coordinate (ATC) view of GYT biplot, the genotypes No. 5, 3 and 4 in terms of all positive yield-trait combinations were recognized as the best genotypes and genotypes No. 7, 13 and 6 as the weakest genotypes. According to the results, a significant positive correlation was observed between stem diameter, head diameter, plant height and early maturity in combination with seed yield. Therefore, it seems that traits of stem diameter, head diameter, plant height and early maturity could be used as a suitable selection criterion for increasing seed yield in sunflower.

Generally, the results indicated that hybrids No. 5, 3 and 4 were recognized as superior hybrids from the point of yield and other agronomic traits. These genotypes have the potential to be used in research-extension trials for introduction as a new cultivar for cultivation in the Kermanshah region. Also, the traits of stem diameter, head diameter, plant height, and early maturity could be used as suitable criterions in selecting for increased seed yield in sunflower breeding programs.