Wheat leaf rust caused by Puccinia triticina is very destructive to the susceptible wheat (Triticum aestivum L.) cultivars. Breeding for resistance is still the most economic and desirable method for controlling the disease. The objective of this investigation was to: 1) study the nature of inheritance of leaf rust disease resistance as well as grain yield and its related characters, 2) detect leaf rust resistant genes in the studied cultivars under field condition, 3) evaluate using Sequence Characterized Amplified Regions technique (SCAR) for the leaf rust resistance gene Lr37 and 4) use SCAR as a tool for selecting and pyramiding different Lr's resistance genes in Egyptian cultivars. Combining ability effects were estimated using line × tester matting design. Four high yielding cultivars Giza 168, Sakha 93, Sakha 94 and Gemmeiza 9 as females ( lines) and four leaf rust monogenic lines. i.e., Lr10, Lr19, Lr37 and Lr39 as males (testers). Broad sense heritability (h 2 b) was computed. The Chi-square test (χ 2 ) was used to test the significant of difference between observed and expected ratios in F2 populations for leaf rust reaction. PCR reaction for SCAR primers was applied. The study included four characters; plant height (PH), leaf rust resistance as average coefficient of infection (ACI), number of spikes per plant (S/P) and grain yield per plant (GY/P). The obtained results can be summarized as follow; Sakha 93 was the best general combiner for PH and Sakha 94 for leaf rust resistance and GY/P. The best combinations for PH were Giza 168 × Lr39, Sakha93 × Lr19 and Sakha 94 × Lr37; for leaf rust resistance were Sakha 93 × Lr37, Sakha 93 × Lr39, Sakha 94 × Lr10 and Sakha94 × Lr19 and for yield and its components were Sakha 94 × Lr37 and Gemmeiza 9 × Lr19. Giza 168, Sakha 94 and Gemmeiza 9 had one or two genes conferring resistance to leaf rust. In addition, Lr39 leaf rust resistant gene was present in Giza 168 and Sakha 94. The laboratory studies showed that, the SCAR marker has the potential of detecting Lr37 in the studied Egyptian cultivars as well as the monogenic lines. Moreover, Giza 168, line 1 and line 3 had the leaf rust resistance gene Lr37.

The present research was conducted to study earliness and their correlations with grain yield in rice breeding. It was carried out during 2012 and 2017 growing seasons at RRTC Farm, Sakha, Kafr El-Sheikh, Egypt. F 1 were evaluated along with their parents for genotypic variation. ANOVA revealed significant differences at the 0.01 level among crosses and parents as well as between parents and crosses. These results indicated a wide range of variations among parental groups. The mean squares of parents vs. crosses were found to be significant for all grain yield and its component characters. Variance among crosses indicated significant SCA effects at the 0.01 level for all its component traits. Concerning GCA effects four entries; Sakha 101, Novator, Anait and Large Stigma exhibited positive significant estimates at 0.01 levels for grain yield /plant. The desirable hybrid combinations Giza 179 X Large Stigma and Sakha 105 X VNIRB 572 exhibited significant values of SCA effects at 0.01 and 0.05 levels for grain yield. Heritability estimates in narrow sense ranged from low to moderate. Sakha 101 X Novator, Sakha 106 X Novator and Giza 179 X Large Stigma were the promising hybrid combinations for improving yield character according to results for mid and better parent heterosis. Positive significant correlation coefficient at 0.01 level was recorded between 1000-grain weight and grain yield/plant. All of 11 SSR motifs were polymorphic and produced varying number of alleles with different size ranges. A total of 99 alleles were identified with 10 varieties under study.

This study was conducted to 1) isolate and characterize some rhizobia from some legumes, 2) determine the phylogenetic relationships among them; and 3) investigate their potential biological control agent. 24 Rhizobial isolates were obtained from five legumes namely; faba bean, lentil, pea, clover, and soybean. Morphological characterization classified isolates into fast grower and slow grower. Also, their biochemical profiles using API 20E and API 20NE system showed large diversity which may reflect their adaptation in different environments. Moreover, molecular detection by 16S rDNA gene was able to characterize 19 of them to species level. Isolates from pea, faba bean, clover and lentil were Rhizobium leguminosarum and isolates from soybean were Bradyrhizobium japonicum. This data supported the idea that there is a narrow diversity of species of rhizobia in Egypt. Phylogenetic analysis of the 19 isolates confirmed that the Bradyrhizobium japonicum isolates were phylogenetically divergent from all other isolates. Also, the phylogram revealed that each group of isolates originated from root nodule of a certain legume formed a separate sub-cluster. Besides a narrow range of interspecies variations was found which is consistent with the idea of biovars presence among species. In addition, the 24 isolates showed strong inhibition of growth of Fusarium and Rhizoctonia phytopathogens. However, results indicated that 25% of isolates were not able to solubilize tricalcium phosphate. On the other hand, the IAA production by the 24 isolates varied greatly among isolates. Therefore, these results demonstrated that they may have the potential to act as biocontrol agents. Moreover, we characterize Nod D gene on the molecular level. Upon its isolation its size came to be 820 bp of nucleotides. This came to be true for all bacterial isolates except four isolates we did not succeed to isolate NodD gene. Moreover we used Quantitative Real Time PCR to study NodD gene expression. Seven nod D gene were down regulated and five were up regulated than 16S housekeeping gene.

In the last few decades, there has been a growing interest in environmentally friendly sustainable agricultural practices, thus increasing the role of biofertilizers such as rhizobia, which can decrease the need for chemical fertilizers, reduce adverse environmental effects, and help to save money. Therefore, information on the distribution and genetic variation of native rhizobial isolates would aid in selecting novel rhizobial strains that could be developed and used as biofertilizers in legume production. This research was conducted to characterize 24 rhizobial isolates from five legumes on morphological, biochemical, and molecular aspects and determine the phylogenetic relationships among them. Rhizobial isolates were obtained from five Egyptian legumes: faba bean, lentil, pea, clover, and soybean. Morphological characterization classified the isolates into fast and slow growers. Biochemical characterization using API 20E and API 20NE systems showed a large diversity, which may reflect their adaptation in different environments. Moreover, molecular detection of the 16S rRNA gene enabled to characterize 19 of them to the species level. Rhizobial isolates from pea, faba bean, clover, and lentil were identified as Rhizobium leguminosarum and those from soybean were identified as Bradyrhizobium japonicum. These data reflected a narrow diversity of rhizobial species in Egypt. A phylogenetic analysis of the 19 isolates confirmed that B. japonicum isolates were divergent from all other isolates. Furthermore, the phylogram revealed that each group of isolates that originated from the root nodule of a certain legume formed a separate subcluster. The obtained data suggested a narrow range of interspecies variations, which is consistent with the idea of the presence of biovars among the species.

Line x tester experiment was conducted to evaluate the performance of 25 F1 hybrids along with ten parents in rice at Rice Research and Training Center (RRTC), Sakha, Kafr El-Sheikh, Egypt during 2007 and 2008 growing seasons to estimate the percentage of heterosis and heterobeltiosis among F1 hybrids developed from five lines and five testers of rice. Genotypic mean squares for all studied traits were highly significant and had genetic variability for these traits. Heterosis and heterobeltiosis were estimated for number of days to maturing, plant height (cm), number of panicles per plant, panicle weight (g), 1000-grain weight (g), and grain yield per plant in cross combinations of five lines of rice (Giza 177, Sakha 101, Sakha 103, Sakha 104 and one promising line GZ6903-1-2-2-1) and five testers (IRBLI-F5, IRBLzFU, IRBLz5-CA, IRBLTACT2 and IRBLSH-B). The resultes exhibited significant differences among genotypes and their crosses for all studied traits. The crosses Sakha 101 x IRBLzFU and Giza 177 x IRBLzFU depicted significant heterosis and heterobeltiosis for grain yield and most of the other studied traits followed by Giza 177 x IRBLI-F5. Heritability estimates in broad sense were high for all studied traits. While, heritability estimates in narrow sense were relatively low for all traits.