An improved methodology for detecting underestimated remobilization in common wheat (Triticum aestivum L.) stems: Impacts of underestimation on remobilization related traits

To measure carbohydrate remobilization, analysis of the entire stem can yield underestimated results in wheat cultivars with simultaneous carbohydrate accumulation and remobilization in their internodes. This study aimed to develop a new method for the rapid identification of underestimated remobilization. In addition, the influence of this underestimation on remobilization–related traits was examined. 18 wheat cultivars were assessed under Mediterranean and subtropical climatic conditions. Sequential measurements of the entire stem axis and individual internodes were taken at short intervals from anthesis to maturity, with particular attention to the timing of their peak weights. Due to space limitations, only data from the subtropical climate are reported. Results showed that, in 11 cultivars, dry matter remobilization in the lower internodes began significantly earlier than in the peduncle and penultimate internodes. For these cultivars, reliance on the entire-stem weight underestimated actual remobilization by 5 mg to 203 mg, leading to inaccurate cultivar ranking. Additionally, in cultivars in which internode dry matter accumulation and remobilization overlapped, calculating remobilization efficiency based on entire-stem weight failed to provide accurate assessments. In other cultivars, discrepancies were observed between remobilization efficiencies calculated from entire-stem weight and those calculated from individual internodes. Finally, underestimation of entire-stem remobilization reduced estimated contribution percentages by 1.0 % – 11.0 % compared with cumulative internode contributions. Therefore, for a more precise measurement of carbohydrate remobilization in wheat stems, separate measurement of this trait in each internode is highly recommended.