Changes in stem and spike related traits resulting from breeding in Iranian wheat cultivars: associations with grain yield

Abstract

. Genetic improvement over time in specific stem weight (SSW) along with significant positive correlations between this trait and grain yield were observed at Karaj under DS conditions and at Parsabad, suggesting that SSW could be used as an indirect selection criterion for yield in these environments. Time-dependent changes in spike dry weight showed that the accumulation of photoassimilates in the spike from anthesis to 16 days after anthesis (16 DAA) was not changed by breeding. However, during the 16 DAA -maturity phase, modern cultivars had more photoassimilates allocated to the spike than the old ones. This suggests that the sink is more limited during early grain growth than during the end of grain filling.

Assessing the Impact of Nitrogen Fertilization, Variety Selection, Year and Their Interaction on Wheat Yield and Yield Components

“…Additionally, the results suggest that the new varieties, 'Luiza' and 'Itri', have been optimized for high grain yield-a finding, which resonates with the complex trait interplay reported by Zhang et al (2020) [53]. The 'Faraj' variety seems to have been bred with a focus on spike density-a trait highlighted for its importance in wheat yield by Joudi et al (2017) [54]. The association of the 'Nassira' variety with high TKW suggests an emphasis on breeding for grain weight-a trait positively correlated with grain yield, as reported by Alonso et al (2018) [55] and Racz et al (2019) [56].…”

Bioavailable Grain Iron Declines From Old to Current Pakistani Bread Wheat Cultivars

“…Spike length and spike weight increased in varieties and advanced lines indicating the increase in sink size in modern genotypes compared to land races. Increase in allocation of photoassimilates to spikes in modern cultivars of wheat compared to older ones, suggests increased sink size in modern cultivars (Joudi et al 2017). The correlation analysis revealed spike length and spike weight positive correlations with grain yield and other yield contributing traits in approved varieties.…”