اثر خشكي و نيتروژن بر انتقال مجدد نيتروژن در تنش رقم گندم

Effect of Drought and Nitrogen on Remobilisation of Nitrogen in Six Wheat Cultivars

A study on nitrogen remobilisation (greenhouse experiment) was conducted at the faculty of Agriculture and Natural Resources, Ramin University (Mollasani) with two levels of N (50 and 150 kgN/ha), while using six wheat cultivars under postanthesis water stress or non-stress conditions, Results indicated that Chamran cultivar had the highest grain yield in comparison with other cultivars in drought conditions. Fong cultivar showed no response to N while Atrak, and Showa were the modrately responsive to N. Nitrogen remobilisation towards grain was varied, however, there was more N mobilization observed in Chamran cultivar. Nitrogen application caused an increase in the amount of N remobilisation. Despite the significant differences among cultivars in N remobilisation, this was not strongly associated with response in grain yield. Also, results indicated that postanthesis water stress caused reductoion .in grain yield at high level of N in comparison with low levels, however this did not influence either grain weight or the amount of protein. Although when postanthesis water stress was low there was large grain response to N but postanthesis water reduced the amount of final grain N. As a whole, use of N fertiliser in wheat cultivars must be in accordence with environment conditions, particulary the amount of existing water as well as agronomic practices which can reduce the effect of water stress during grain filling.