Response of bread wheat to nitrogen fertilization levels in Al-Qassim Region, Saudi Arabia

Abstract EN

-This study considered the effects of six nitro gen fertilization levels (120, 180,240, 300, 360 and 420 kg N/ha ) on the biological and grain yields, yield components, plant height and heading dat e of the commercial bread wheat cultivar "Yeco ra Rojo" .

Two experiments were conducted during the two seasons, 1989/90 and 1990/91 at the Agricultural Experirncnt Station , College of Agricultur e and VeterinaryMedicine, King Saud University , AI-Qassim branch, Saudi Arabia.

The experimentswere set up in a complete randomized block design with four replications.

The results indicate that nitrogen fertil ization levels had significant effects on number of spikes/rrr', number of kernels/spike , and plant height in the two seasons.

High nitrogen levels resulted in significant increases in grain yield, harvest index values and number of days to heading in the second season only.

On the other hand , nitrogen levels had no significant effects on either biological yield or kernel weight , in the two seasons.

It could be concluded that the optimum nitrogen fertilization level for Al-Oassim region lies between 240 and 300 kg N/