The role of different stem segments in the deposition of water-soluble carbohydrates in winter wheat varieties under drought conditions

Abstract

Aim. Evaluation of the role of different internodes and leaf sheaths of winter wheat stem in storage and remobilization of reserve water-soluble carbohydrates (WSC) under natural water deficit in order to develop effective criteria for selection of high-yielding genotypes. Methods. The specific content and total amount of WSC at the onset and the end of grain filling and the quantity of WSC remobilized in different parts of the stem were determined. Results. It was found that the main part of reserve WSC in plants of modern winter wheat varieties was accumulated and mobilized in the 2nd, 3rd and 4-5th (counting from above) internodes, the contribution of peduncle and leaf sheaths was much smaller. The highest WSC depositing capacity of all stem segments were found in the high-yielding variety Kyivska 17 and the lowest one in the less productive variety Poradnytsia. Conclusions. The values of accumulation and remobilization of WSC in the 2nd and 3rd from the top internodes can characterize the storage capacity of the stem and be used to assess the relationships with grain productivity in the breeding winter wheat in arid conditions.