Two field experiments were carried out at Sakha, Agricultural Research Station during 1999 and 2000 seasons to study the response of late sowing cotton cultivars (Giza 88) to three nitrogen levels (30, 45 and 60 kg Nlfed) as a main plots and three timin.

his work was established at Mataana Agricultural Research Station, Upper Egypt, during 1990 / 91 and 1991 / 92 seasons to study the relationships between durations of irrigation cycles and yield, also water relations for wheat cultivar Sakha 69. Irrigation was applied at four treatments i. e. durations of irrigation cycles of about 8, 13, 17 or 28 days. Results showed that grain or straw yield, water use efficiency (WUE) or seasonal evapotranspiration (ET) linearly decreased by increasing the durations of irrigation cycles ; while, (WUE) linearly increased by increasing seasonal (ET). Moreover, results indicate that soil moisture extraction from the upper 30 cm as a percentage of seasonal (ET) as affect ed by irrigation treatments of about 8, 13, 17 and 28 day cycles was 79. 68, 77. 47, 75. 89 and 70. 71% as averages for the two seasons. As well as daily soil moisture extraction from each depth reached to peak use rate after 100-137 days from planting. Seasonal (kc) for Blaney-Criddle formula was 0. 835, 0. 768, 0. 759 and 0. 719 for irrigation cycles of about 8, 13, 17 and 28 days in the first season, respectively ; whereas, in the second season it was 1. 000, 0. 952, 0. 909 and 0. 843 for the same respective treatments.

Two field experiments were carried out at Mallawi region, Naway village, Minia governorate, during the two successive seasons of 2006 and 2007 to study the effect of application amount of potassium, 0, 24 and 48 kg k₂O/fed, and nitrogen, 60 and 90 kg N/fed, on the response of cotton cultivar Giza 80 to water stress imposed by extending irrigation intervals from every two weeks to be every three week. Results of this study could be summarized as follows: Irrigation intervals every three weeks resulted in significant reduction in plant height, number of fruiting branches/plant, number of open bolls/plant and seed cotton yield (kentar/fed) in the two studied seasons, and leaves content of K and seed index in 2007 season only. Increasing K amount up to 48 kg k₂O/fed significantly increased leaves content of N and K, yield and yield components but significantly decreased lint, however, the differences were not always significant between the lower K level (24 kg k₂O/fed) and the control or between the two amounts of K. Increasing N amount from 60 to 90 kg N/fed significantly increased leaves content of N and K, plant height and at number of fruiting branches/plant in both seasons but, it fuiled to exert any significant effects on yield or yield components except for number of open bolls/plant in 2006 season only. The interaction of irrigation intervals x K amount significantly affected only seed cotton yield and seed index in both seasons when K application increased both traits under longer irrigation intervals greater than under closer ones. The interaction between irrigation intervals and N fertilization exhibited significant effects only on plant height in both seasons and number of fruiting branches/plant in 2007 season only when growth of well-watered plants responded to increasing N amount more favorably than that of water stressed plants. The interaction of Irrigation intervals x K x N or the interaction of K x N exerted no significant effects on all studied characteristics in both seasons. It could be concluded from this study that increasing K amount significantly increased seed cotton yield particularly under water inadequacy conditions otherwise, increasing N amount to 90 kg N/fed failed to significantly increase seed cotton yield at either longer or closer irrigations intervals.

In this investigation, six cotton cultivars were involved. The cotton fibers of each variety were spun at different counts and twist multipliers. The results of the effect of yarn of yarn count and twist multiplier on yarn properties could be summarized

The present investigation was carried to study the effect of nitrogen levels, hill spacing and rice cultivar mixture on rice characters. Three nitrogen levels (40, 60 and 80 kg N / fed.), three hill spacings (10 x 20, 15 x 20 and 20 x 20 cm) combined with five rice cultivar mixtures (25% Giza 177 with 75% Sakha 102, 75% Giza 177 with 25% Sakha 102, 50% Giza 177 with 50% Sakha 102, 100% Giza 177 and 100% Sakha 102) were used. A split-split plot design with three replications was used. The results revealed that the mixed rice variety (25% Giza 177 with 75% Sakha 102) transplanted at 15 x 20 cm and fertilized with 60 kg N / fed. gave the highest values of number of tillers / m^2, number of panicles / m^2, panicle weight (g), panicle length (cm), number of filled grains / panicle, 1000-grain weight (g), grain yield (t / ha), biomass yield (t / ha), harvest index %, hulling %, milling % and head rice % in both seasons of study.