Stem water soluble carbohydrate remobilization in wheat under heat stress during the grain filling
2015
Zamani, M.M. (University of Shahid Chamran, Ahvaz (Iran). Dept. of Agronomy and Plant Breeding) | Nabipour, M. (University of Shahid Chamran, Ahvaz (Iran). Dept. of Agronomy and Plant Breeding) | Meskarbashee, M. (University of Shahid Chamran, Ahvaz (Iran). Dept. of Agronomy and Plant Breeding)
The environmental conditions in regions with Mediterranean climate are favorable for wheat (Triticum aestivum L.) growth until the anthesis but afterwards exposed to terminal heat stress. Relative contribution of stem reserves during grain filling is assumed to increase compared with current photosynthesis. This study evaluated the ability of different wheat genotypes for accumulation and remobilization of stem water soluble carbohydrate (WSC) under the heat stress conditions during the grain filling. Ten spring bread wheat genotypes were grown under controlled conditions of phytotron with two temperature treatments i.e. normal and heat stress. There was significant variation among the genotypes for WSC concentration and remobilization. WSC remobilization increased under heat stress (on average 60%). Strong association between maximum WSC concentration in main stem and WSC remobilization was found. Under heat stress, the number of grains per spike correlated with WSC remobilization (r= 0.45) and correlation of percentage reduction of grain yield with WSC remobilization efficiency was negative (r = -0.47). However, there was no significant relation between grain yield and stem reserves remobilization under heat stress during grain filling. It seems that the tolerance to the heat stress would be provided either through maintenance of current photosynthesis or by high remobilization of stem reserves.
显示更多 [+] 显示较少 [-]