Comparison of internode -related traits in ten wheat cultivars

The aim of this research was to compare the different stem internodes and study on partitioning pattern of length, weight and specific weight among wheat stem internodes. Ten wheat cultivars were grown at research farm of Agricultural Research Center of Moghan under well watered conditions during 2015-2016 growing season. Stem-related traits were measured at physiological maturity and their relationships with spike dry weight were investigated. Averaged among cultivar, the longest internode was peduncle (39.6 cm) followed by the lower internodes (28 cm) and penultimate (19.4 cm). The highest weight was observed in the case of the lower internodes which was 486.1 mg. Averaged values of peduncle and penultimate weight were 340 and 254.3 mg, respectively. The highest value of internode specific weight (obtained from ratio of internode weight to internode length) was observed in the case of the lower internodes (17.7 mg/cm). Penultimate (13.1 mg/cm) and peduncle (8.6 mg/cm) were in the next ranks. Correlation analysis revealed that there are no significant relationship between stem length and weight (recorded at physiological maturity) with spike dry weight whereas stem specific weight correlated significantly and positively with spike dry wright, suggesting that stem specific weight could be considered in wheat breeding programs.