Two field experiments were conducted at extension farm, in EI-
Mansoura Agric. Center, Dakahlia district, Egyp < /span>t during 96/1997 and 97/1998
seasons to study the effect of fertilization treatments, foliar app < /span>lication times
on performance of some wheat cultivars as well as their interaction on growth
yield and yield comp < /span>onents. Also, to study the interrelationship between grain
yield/fad and. yield components through simple correlation coefficients
multiple linear regression and step < /span>wise regression analysis the trails were
arranged in a strip p < /span>lot design with four rep < /span>lications. The main findings could
be summarized as follows: 1-The biological fertilizer of Syrialin + Phosphorin (400 gm/fad) + 40 m3Farmyard manure maximized flag leaf area, p < /span>lant height, number of tillers and sp < /span>ikes,· sp < /span>ike length, grain weight/sp < /span>ike, number of grains/sp < /span>ike, p < /span>rotein
percentage, grain and straw yields/fad compared with other fertilizer treatments in both seasons. 2-Foliar application of Super Grow at tillering + elongation stages produced highest values of flag leaf area p < /span>lant height number of tillers and spikes /m2and grain yield/fad comp < /span>ared with other times of app < /span>lications. Meanwhile, foliar spraying at heading and/or tillering + elongation stages significantly increased 1000 grain weight, protein p < /span>ercentage and straw yield/fad without significant differences between them in both seasons. 3- The studied wheat cultivars markedly varied in all estimated characters. Sids 8 cultivar surpassed the other two cultivars i.e. Sakha 69 and Gemmaza 3 in flag leaf area, spike length, number of sp < /span>ikelets and grains
number/spike, 1000 -grain weiqht, grain protein percentage and grain
yield/fad. However, Gemmaza3 cultivar exceeded Sakha 69 and Sids8
cultivars in plant height, number of tillers and sp < /span>ikes/rrr', grain weight/sp < /span>ike
and straw yield/fad in both seasons. 4- The interaction between fertilization treatments and wheat cultivars showed significant effect on number of tillers and spikes/m", grain and straw yields/fad in both seasons. The interaction between times of foliar spraying . of Super Grow and wheat cultivars had a significant effect on number of grains/sp < /span>ike, 1000-grain weight, grain and straw yields/fad in both seasons. 5-A positive and significant correlation coefficients was found between grain yield/fad and each of plant height, number of tillers/m2, flag leaf area, sp < /span>ike
length, spike weight, spikes number /m2, spikelets number /spike, grains
number / spike, grain weight / sp < /span>ike and 1000-grain weight. . 6-Multiple linear and stepwise regression analysis indicated that plant height (3.83 % , 6.06%) number of spikes-zm" (69.64% , 77.93 %)and grain weight /sp < /span>ike (56.66% , 63.99 %)had high relative contributing towards grain yield/fad in p < /span>rediction equation, respectively. In genera, it could be summarized that for maximizing grain/fad per unit area by using Syrian + Phosphorin (400 mg/fad)+40m3Farmyard manure and foliar application (Super Grow) at tillering + elongation stages and using sides 8 cultivar was recommended treatment under the environment condition of Dakahlia district.