Study of assimilate amount changes' effect on duration of flowering in three wheat cultivars on grain filling rate, yield and yield components in Mazandaran.

摘要

Determination of assimilate limitation in wheat can be an important step in finding out production restrictive factors of this crop. In this research, this has been carried out by randomized complete blocks of factorial experimental design in four replications in Mazandaran in 2007. Two factors were studied in this experiment. The first factors were cultivars, which consist of Shanghai, Zagros, Tajan. The Second factor were assimilate amount change treatments at four levels which including: check, half, full flag leaf cutting and radiation increasing. Selective spikelets cutting used to determine grain growth. The results showed that cultivars have significant differences at 1% level in grain yield, biomass, grain weight, main spike kernel weight. The highest kernel weight and main spike kernel weight with averages 34.04 and 42.09 mg related to Zagros cultivar. Therefore, Tajan has higher yield in stress conditions. Also, the results of assimilate ratio changes treatments emphasize that these treatments have very significant effect on grain yield, biomass, grain weight, main spike kernel weight and harvest index. Radiation increasing treatment comparison to check cause to increases grain yield and kernel weight and main spike kernel weight and harvest index. Full flag leaf cutting comparison rather than check treatment leads to reduction in grain yield and biomass and main spike grain weight and 1000 kernel weight and harvest index. Assimilate changes treatments had very significant effect on grain filling rate. The half Flag leaf cutting caused decreases of grain filling rate.