Productivity of maize (Zea mays L.) and nitrogen use efficiency (NUE) as affected by nitrogen application levels and timing were studied. The experimental design was a three-replication randomized complete block design (RCBD). The first factor was nitrogen levels (122, 240, 288 and 336 kg N/ha) and the second factor was nitrogen timing (50% of N at sowing and 50% of N before the first irrigation; T1, 50% of N at sowing and 50% of N before the second irrigation; T2 and 50% of N before the first irrigation and 50% of N before the second irrigation; T3). Results indicated that plant height, ear length, kernel weight, number of grains/rows, number of grains/ear and grain yields all increased significantly as nitrogen levels increased and the level of 336 kg N/ha significantly exhibiting the highest values in both seasons. In terms of nitrogen application time, maize yield parameters such as plant height, ear length, kernel weight/ear, number of grains/rows, number of grains/ear and grain yield were significantly affected by nitrogen timing, with the highest values obtained at T3 while the lowest values obtained at T1 in both seasons. The interaction had a significant impact on plant height and grain yield/ha, with the tallest plants, the highest yields and its components observed at 336 kg N/ha, with 50% of N applied during the first irrigation and 50% of N applied during the second. Furthermore, under the study conditions, NUE decreased dramatically as nitrogen levels increased and increased significantly as nitrogen application time changed.

Pomegranates fruit cracking and poor coloration of peel and aril are the main problems facing the expansion of its cultivation especially under arid condition in the desert. This study was conducted during the two successive seasons 2014 and 2015 on "Wonderful" pomegranates (Punica granatum L.). The trees were grown under drip irrigation system in a private orchard at Nubaria region, Beheira Governorate, Egypt. The trees were treated twice at weekly interval by using a hand sprayer to the run off point at the marble size with some mineral nutrients to reduce fruit cracking. The treatments included: water spray (as the control), calcium borate at 100 ppm, calcium borate at 200 ppm, zinc chelated with EDTA at 100 ppm, zinc chelated with EDTA at 200 ppm and finally calcium nitrate at 1% (W/V). Moreover, to enhance coloration of pomegranates peel and aril, at maturity the trees were treated with the control (water spray), ProTone (ABA 1%) at 100 ppm, ProTone at 100 ppm plus glycerol at 1% (V/V), ProTone at 100 ppm plus potassium sulphate at 1% (W/V), ProTone at 100 ppm plus potassium sulphate at 1% and glycerol at 1% (V/V), glycerol at 1% (V/V) and finally potassium sulphate at 1% (W/V). The non-ionic surfactant Top film at 0.05% (V/V) was added to all treatments. The results proved that calcium borate at 200 ppm treatment was more effective on reducing cracking and sun scald of pomegranate fruits. In addition, the results revealed that the formulation containing ProTone plus potassium sulphate and glycerol had a consistent effect on increasing anthocyanin content in the peel, when compared with the control or with ProTone alone. Moreover, anthocyanin content of the arils was significantly increased by application ProTone along with glycerol or ProTone plus potassium sulphate and glycerol in both seasons. Meanwhile, electrolyte leakage of the aril was similar for most applications. There was also a significant increase in total sugars by various ProTone-containing formulations relative to the control in the juice. Thus, this study recommended applying ProTone in a formulation containing potassium sulphate and glycerol in order to enhance coloration and quality of "Wonderful" pomegranates in a consistent manner under field conditions.

The base population for the recent study which is ayellow seed synthetic variety of maize was provided by Dr. M. Abd El-Sattar Ahmed, professor of crop science, Crop Science Department, faculty of Agriculture, Egypt.Two types of families had formulated, as a step before selection for high yielding ability. Those were half-sib (H.S) families and the first generation of self-pollination(S 1 ) families. Variability in the base population gene pool had estimated depending on variance components of the families. The ratio of σ 2 A / σ 2 G indicated that, additive genetic variance was more effective in controlling green and dry forage yield. This might indicate the importance of additive genetic variance in maize population, consequently, selection among inbred-progeny would expect to be superior to other methods under most genetic situations. Reduction in mean values of forage yield associated with selfing, reached 0.62 and 0.57 for green forage yield (Kg/ plot) and dry forage yield (Kg/plot), respectively. Values of genotypic variances estimated from S 1 families were of larger magnitude amounted to 1.63 and 1.94 times the corresponding values for half-sib families in green forage yield and dry forage yield. Opposite to that, environmental variance estimates from S 1 families were 0.56 and 0.55 of the respective values from half-sib families in green forage yield and dry forage yield respectively.Genotypic variations in term of coefficient relative to the overall mean of green yield and dry yield were less than 20%of the character mean when estimated from half-sib and S 1 families (10.85 vs. 13.96 and 10.21 vs. 14.31% for green and dry forage, respectively).Dry forage yield expressed the highest estimates of heritability in both family types (0.829 and 0.877 for half -sib and S 1 families, respectively). While, the obtained values for green forage yield were of lower magnitude (0.53 and 0.67 for half-sib and S 1 families, respectively). This might indicate additional environmental influences with green forage yield.

The base population for the recent study which is a yellow seed synthetic variety of maize was provided by Dr. M. Abd El-Sattar Ahmed, professor of crop science, Crop Science Department, faculty of Agriculture, Egypt. Two types of families had formulated, as a step before selection for high yielding ability. Those were half-sib (H.S) families and the first generation of self-pollination (S 1 ) families. Variability in the base population gene pool had estimated depending on variance components of the families. Reduction in mean values associated with S 1 families relative to half-sib families reached 0.182, 1.18, 0.98, 3.88, 2.75 and 5.72% for leaves percentage, stem percentage, ear percentage, grain percentage, cob percentage and husk percentage, respectively. Genotypic variances among S 1 families was larger in magnitude than the respective value for half-sib families in each measured botanical composition and dry matter partitioning characters. Meanwhile, within family's variance, (σ 2 f ), environmental variances (σ 2 e ) had reduced in S 1 families relative to half-sib families in each measured character. Genotypic variation among half-sib and S 1 families were less than 20% of the studied botanical composition and dry matter partitioning characters mean values, except for cob percentage and husk percentage that had a genotypic variation amount to 24% and 26%, respectively. The estimates of additive variance (δ 2 A ) were positive for all studied botanical composition and dry matter partitioning characters. While, the estimates of dominance variance (δ 2 D ) were negative for all characters, the ratio of δ 2 A /δ 2 G indicated that additive genetic variance was more effective in controlling all studied botanical composition and dry matter partitioning characters. Estimates of heritability were higher in magnitude when calculated from first selfing generation (S 1 ) compared to half-sib families, for all studied characters. Stem percentage expressed the least estimate heritability among all studied characters in each family type (0.798 and 0.414 for half-sib and S 1 families, respectively). This might indicate the influence of environment in the expression of that character. Meanwhile husk percentage had highest genetic control expressed on heritability estimates from the two studied types of families.