Effects of internodes dry matter remobilization on linear rate of grain growth in wheat cultivars

The aim of this research was to study the amount of dry matter accumulation and remobilization in different stem internodes and their effects on linear rate of grain growth in wheat cultivars. 18 wheat cultivars were grown at the research farm of Moghan College of Agriculture and Natural Resources under well-watered conditions during 2014-2015 growing season. Averaged among cultivars, maximum weight of the lower internodes (778 mg) was higher than those of penultimate (462 mg) and peduncle (423 mg). The same trend was observed in the case of dry matter remobilization from the internodes where mean remobilization from the lower internodes, penultimate, and peduncle were 360, 201, and 137 mg, respectively. Among tested cultivars, Alvand and Niknejhad showed higher potential of dry matter accumulation and remobilization in their internodes. Linear rate of grain growth ranged from 44 (Sardari) to 130 (Crossed Alborz) mg spike-1 day-1. Clear corelation were not found between stem grain yield and 100-grain weight with remobilization; however positive correlation was observed between linear rate of grain growth and remobilization, showing the importance of stem dry matter remobilization in wheat grain formation.