Photosynthetic material remobilization and its contribution to barley yield

Abstract The objective of this work was to evaluate the effect of seed rate, genetics, and environmental conditions on the remobilization of stored material from vegetative organs, as well as the contribution of this material to barley (Hordeum vulgare) grain yield. The experiment was carried out in a factorial randomized complete block design with four replicates, in the city of Gonbad Kavous, Iran, in 2016–2017 and 2017–2018 crop seasons. Two factors were evaluated: four seed rates (200, 300, 400, and 500 seed per square meters) and four barley genotypes ('Fardan', 'Khorram', 'Mahoor', and 'Sahra'). Material remobilization with an increasing seed rate per square meter contributed to barley grain yield, especially in the first year, when rainfall was lower. The highest and lowest contribution of remobilization to barley grain yield are related to the penultimate leaf and the flag leaf, respectively. In both years, 'Khorram' and 'Mahoor' genotypes show the highest and the lowest rates for reduction in grain yield, respectively, due to the increased seed rate per square meter.