Six yellow inbred lines of maize, were setup in a half diallel crosses mating design, to produce 15 F1 hybrids. All genotypes with the three commercial checks : SC 155, SC 162 and SC 170 were evaluated using the two nitrogen levels : 80 and 120 kg N/fed during the 2007 growing season at Sakha Agriculture Research station Kafr El-Sheikh. The aim of this study was to estimate the phenotypic and genotypic correlations, GCA, SCA and their interactions with the two nitrogen levels. The results would also identify the superior genotypes for yielding performances. The studied traits were : grain yield (Ard./fed)., ear length (cm), ear diameter (cm), number of rows / ear and weight of 100 kernels(g).The results indicated the presence of significant differences among genotypes for most studied traits .This finding was expected due to the different origin of the parental inbred lines.General combining ability (GCA) and specific combining ability (SCA) mean squares were significant or highly significant for most studied traits under both nitrogen levels. The interactions between GCA and SCA with nitrogen levels were not significant for all studied traits except for SCA x N which was significant for weight of 100 kernels(g).The values of SCA mean squares were higher than those of GCA mean squares for grain yield (Ard./fed.), No. of rows / ear and weight of 100 kernels(g) traits. All means were higher under the high nitrogen level than the low nitrogen level for all studied traits.The best general combiners for grain yield (Ard./fed.) were the inbred lines: Sk 5001/50 and Sk 7070/62.The single hybrids Sk5001/50 x Sk 5005/ 12, Sk 5002/9 x Sk 5005/16, Sk 5001/50 x Sk5005/16 and Sk 5002/9 x Sk 5001/5 showed positive significant SCA under the two nitrogen levels for grain yield Ard./fed.The phenotypic and genotypic correlations among the five studied traits were positive for all studied traits.

The objective of this study was to determine the genetic parameters involved in immature embryo culture ability in wheat (Triticum aestivum L). For this purpose, five lines and two cultivated varieties were used. These lines were: C.B243, C.B245, C.B249, C.B251 and C.B253. While, the two testers were Gemmieza 9 and Gemmieza 10. The results showed the presence of highly significant differences among genotypes for all in vitro traits. This indicated that embryogenic calli induction and its regeneration were affected by the genotypes of the immature embryo donor plants. The line C.B 251 was the most responsive for both embryogenic calli ratio and regenerable calli ratio, while the line C.B243 was the best combiner among other lines in the case of callus fresh weight. The beast combination for all traits was the cross C.B 251× Gemmieza 9. Furthermore, the results revealed that both additive and nonadditive genetic variances played an important role in the inheritance of immature embryo culture traits. However, the magnitude of non-additive genetic variance was larger than their corresponding estimates of additive genetic variances for callus fresh weight and regenerable calli ratio. This finding was emphasized by the dominance degree value which exceeded unity with respect to these traits. Therefore, it could be concluded that using F1 hybrids for immature embryo culture improvement the ability to induce high ratio of plantlets.

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In this investigation 11 inbred lines of maize were used. These inbred lines were crossed among them to obtain 30 F1 hybrids according to factorial mating design. DNA finger printing was made by using RAPD-PCR for all 11 maize inbred lines. The two primers, XD8 and XD9 were used in this technique. The results showed similarity between inbred lines. The results also revealed the presence of three common bands between all inbred lines at primer XD8, while five common bands were obtained at primer XD9. Cluster analysis for similarity degree between the 11 parental inbred lines was done and showed similarity degree between the within inbred lines. Phylsgenetic analysis showed high similarity coefficient between the inbred lines 6, 4 and 2, 3. However, there were high genetic distances obtained between inbred lines No: 4, 5, 6, 7 and 11.

In this investigation, α-amylase gene region from a thermophilic Bacillus stearothermophilus isolated from sugar beet juice obtained from Dakahlia Sugar factory (Egypt) was cloned to competent Bacillus licheniformis ATCC 27811 cells. The original and modified Bacillus strains were spread on different media composition and enzyme activity was determined. According to the results, the α-amylase enzyme was seen to have highest activity at media containing sugarcane bagasse and/or sugar beet pulp. The results revealed that modified Bacillus surpassed the original one at all studied media. This obtained result proofed that gene transferred into BL had effective action on increase α-amylase activity. The thermo-stability studies revealed that enzyme activity of modified bacillus was high for the first 8 hours at 90°C, it was ranged from 95-90 % after 6 hours (enzyme activity decreased from 7.80 to 7.02 gm glucose/ml) then, decreased to 65-63 % at the end of 24 hours.