wheat (Triticum aestivum L. cv. Yecora rojo)‎ performance as affected by seeding rates and nitrogen fertilization

الملخص EN

Field studies were conducted at two locati ons in the eastern and northern regions of Saudi Arabia during 1991, 1992 and 1993 to determine the effects of nitrogen fertilization and seed ing rates on yield components and grain yield of bread wheat , cv.

Yecora rojo .

Nitr ogen from 40 to 240 kg/ha and seeding rates from 120 to 210 kg/ha were applied .

Incre asing N up to 200 kg, resulted in gradual , significant and con sistent increase in numb er of spikes/m", number of grains/spike, 1OO0-grain weight and , ultimately grain yield .

A linear response of wheat to levels of fertilizer nitrogen was observed at Ha il and a curvilinear respon se at AI-Hassa.

However , yield components and grain yield decreased with incre ased seeding rate s.