During this study, 21 garlic genotypes consisted of ten clones of Egyptian cultivar, nine clones of Chinese cultivar, as well as their original populations were evaluated to estimate the extent of improvement in four yield component traits after six cycles of clonal selection. Also, simple phenotypic correlation among these traits and their relationship with yield. Besides estimating linear and quadratic responses (simple and multiple regression); to clarify the relationship between yield and the four studied characteristics. This research has been conducted at the Research farm of Faculty of Agriculture in “Abies” area of Alexandria University, Egypt, for 2020/2021 during the winter season, in a randomized complete block design with three replications. The studied traits were included bulb weight, cloves weight per bulb, average clove weight, cloves number per bulb, and yield per plot. T-test in group reflected a significant improvement in the four yield components traits, whether in the improved clones of Egyptian or Chinese cultivar. The results illustrated, also, that yield per plot showed a highly significant positive correlation with bulb weight, cloves weight per bulb, and average clove weight. Stepwise regression indicated that more than 98% of the variation in yield is explained by bulb weight, average clove weight, and cloves number per bulb. Thus, high yield of garlic plants can be obtained by selecting breeding materials with these aforementioned three variables.

Two field experiments were conducted at Agricultural Research Station, Faculty of Agriculture, Alexandria University, Egypt, through summer seasons of 2015 and 2016 to investigate the effect of six main factors (irrigation, potassium, phosphorus and nitrogen fertilization, sewing date and plant density) on some quality parameters i. e.(oil, starch, total sugar content and oil yield / ha) of maize cultivar Giza 168. A five- levels- six- factor Rotatable Central Composite Design (RCCD) was adopted in the present study. The results indicated that early sowing in May increased starch and oil contents of maize grains, while increasing plant density above 60,000 plants /ha led to decrease in starch content. Oil yield was positively increased with increasing plant density due to increase in grain yield. Nitrogen and potassium fertilization increased oil and starch contents of the grains up to 258 kg N/ha and 136 kg K2O/ha, respectively. Total sugars were positively influenced by increasing levels of all studied factors, except phosphorus where it showed a negative relationship as P level was increased above 50 kg P2O5 / ha.

A field research study was conducted at the experimental station of the Faculty of Agriculture, Alexandria University during 2017/2018 and 2018/2019 seasons to investigate the effect of three sowing dates (1, 15 and 30 November) and three phosphorus fertilizer rates (zero, 36 and 72 kg P2O5/ha.) on straw and seed yields and their components beside seed oil content of Sakha 5 flax cultivar. The obtained results showed significant effects for both sowing dates and phosphorus fertilizer rates, with significant interaction between them on seed index and number of seeds/ capsules in the second season (2018/2019) and seed weight/ plant in the two seasons. The first and second sowing dates were not significantly different from each other in straw yield/ha, but they significantly dominated over the yield of the third sowing date in both seasons. Straw yield/ha ranged from 7.45 to 8.16 t/ha in the first season and from 7.90 to 8.38 t/ha in the second season. The sowing date of 15th Nov. significantly increased number of capsules/plant and seed yield/ha more than the other two sowing dates. The highest seed yields/ha were 2.55 and 2.50 t/ha under 15th Nov. sowing date in the two seasons, respectively, followed by 30th Nov. date. Application of 36 kg P2O5/ha produced the highest means of straw yield and straw yield components but no significant differences were found between the 36 and 72 kg P2O5 /ha for these traits. The highest means of seed yield and seed yield components were detected under the 36 kg P2O5/ha rate with significant differences from the highest phosphorus fertilizer rate or zero phosphorus fertilizer. The highest oil percentages were 46.51% and 46.68% under the 36 kg P2O5/ha rate in the two seasons, respectively, followed by the highest rate while the lowest oil percentages were 45.09 % and 45.08% under zero phosphorus fertilizer in the two seasons, respectively. Regarding the significant interaction effect, the obtained results indicated that 30th Nov. with 36 kg P2O5 /ha gave higher values of seed index and number of seeds/ capsules in the second season, seed weight/ plant increased with both 15th or 30th Nov. under 36 kg P2O5 /ha in the first season, whereas in the second season the highest value was obtained for 15th Nov. under 36 kg P2O5 /ha.

Sunflower is an important oil crop that has received great attention by the Egyptian agricultural sector in the early nineties, when a boom in oil extraction from the crop was observed. Since then and for more than two decades, sunflower for oil purpose was neglected, hybrids are no longer on the market and confectionery sunflower became more profitable for Egyptian farmers. The aim of this study was to evaluate effect of sowing date (April vs. August) and preceding crop (maize vs. sunflower) in a double cropping system, under varying nitrogen fertilization levels (36, 72, 108 and144 kg N/ha), on growth and productivity of the newly introduced sunflower hybrid Sirena. Results from two year experiments, have indicated that April sowing, at a prevailing average temperatures of 20-24oC later rising to about 28oC at harvest time, was suitable to secure maximum seed yield of 4.39 ton/ha. In a double cropping system, where sowing was performed in August, the hybrid yielded an average of 3.4 ton/ha, whether preceded by maize or sunflower. Seed oil percentage amounted to an average of 42.8% and was affected by the year, rather than sowing date or preceding crop. Effects of the nitrogen fertilization rates were masked by the soil available nitrogen, however, based on the regression analysis and equations for estimating the nitrogen requirements based on the hybrid seed yield, 72-108 kg N/ha were necessary to achieve the maximum seed yield while sustaining an oil percentage above the 42%.

This study was carried out in 2017 and 2018 seasons to investigate effect of nutrient mixture and potassium levels applied as spray or to soil on sunflower yield and its components using split-plot design with four replicates. Main plot treatments were: K1 (control) without K, K2: 57 kg K2O/ ha, K3: 114 kg K2O/ ha (K1, K2 and K3 as soil application), K4 (control): spraying with tap water, K5: 0.58 kg K2O/ ha and K6: 1.16 kg K2O/ ha (K4, K5 and K6 as foliar application). Sub-plot treatments were 0, 1 and 2 liters of nutrients mixture per hectare. K5 treatment produced the heaviest heads(132.0g),highest seed weight/ head(69.98g)in the first season and highest oil (41.33%) without significant differences with potassium soil application treatments in that season. (K6) produced the thickest stems(2.28 and 2.31cm)in both seasons, largest head (20.54cm), heaviest heads (122.49g), highest shelling (52.81%) and heaviest 100-seed weight (8.26g) in the second season, whereas (K5 and K6) treatments gave the heaviest seed weight/ head (60.99 and 64.70 g), and highest shelling (53.03 and 53.02%) in the first season and seed yield/ ha (3.35 and 3.55ton) in the second season. Foliar application of nutrients mixture significantly increased all the studied treatments, except head diameter in 2017, stem diameter, 100-seed weight and oil percent in 2018 season. Interaction had significant effect on plant height, head weight, shelling % and harvest index in both seasons. K5 and/ or K6 combined with nutrient mixture foliar application, generally, increased the aforementioned traits under Alexandria Governorate.

Balancing maximum biomass yield with high nutritional quality and reduced environmental impact remains a primary challenge in sustainable summer forage production for livestock, a challenge intensified by competition between conventional and forage crops for agricultural land, particularly regarding planting dates and land occupation duration, which limits available livestock forage resources. To address this issue, this study evaluated the forage yield, quality, and nutritive value of teosinte (Zea Mexicana L.) under three sowing dates: 1 May, 20 May, and 10 June, and three harvest ages: 40, 55, and 70 days after sowing (DAS), under Egyptian field conditions. Results showed that delaying harvesting until 70 DAS produced the highest fresh (34.95 to 46.0 t ha⁻¹) and dry (5.38 to 6.03 t ha⁻¹) yields for the late sowing date (10 June). The in vitro gas production (GP) assay showed that GP was significantly higher for teosinte sown on May 20 and June 10 but declined progressively with advancing harvest age. The NH₃-N concentration decreased (p < 0.05) when teosinte was sown on May 1 and harvested at 40 DAS. True organic matter degradability declined for teosinte sown on May 1, May 20, and June 10 when harvested at 70 DAS, whereas it increased at harvest ages of 40 and 55 DAS for teosinte sown on May 1 and June 10. Teosinte sown on May 1 produced significantly lower methane emissions than that sown on May 20 or June 10, regardless of harvest age (40, 55, or 70 DAS). Overall, delaying harvest until 70 DAS resulted in the highest fresh and dry matter yields but significantly decreased gas production and organic matter degradability compared to earlier harvests, which require future research to optimize the utilization of teosinte.