摘要：Field experiments were carried out to investigate the effect of potassium levels (0,48 kg K20/fed.),nitrogen levels (50,70,90 kg N/fed.) and their combinations on physiological and yield characters of two wheat cvs.Misr 1 and Sids 12.Our results showed that,Sids 12 gave the highest values of physiological and yield characters (chlorophyl content,dry weight/m2,plant height,spike length,number of spikes/m2,number of grains/spike,weight of 1000-grain,grain yield,biological yield (kg/fed) and grain protein content) during both seasons.Increasing nitrogen rate from 50 to 90 kg N/fed.,signficantly increased physiological and yield characters.Application of potassium fertilizer resulted in significant increase in physiological and yield characters compared with control (without K) in both seasons.Application of 48 kg K20/fed.recorded the highest values of all studied characters in both seasons.Interestingly enough that,the interaction between cultivars and potassium levels had significant effect in number of spike/m2 in both seasons and in biological yield in the first season.The interaction between cultivars and nitrogen levels recorded significant values in spike length in the first season,grain yield character in the second season,number of spike/m2,biological yield in both seasons.The combination between nitrogen and potassium levels had significant effect on dry weight of plant/m2,chlorophyll content and plant height in the second season,number of spike/m2,biological yield,grain yield and crude protein percent in both seasons.While,the interaction between cultivars and combination of potassium and nitrogen recorded a significant effect in biological yield in the first season and in both number of spike/m2 and grain yield in the two seasons.Application of 90 kg N/fed.along with 48 kg K20/fed could be recommended for the heighest grain yield of wheat cv.Sids 12 under Kafr El-Shiekh Governorate condition.
