In this study, we examined eight white inbred lines of maize and their F1 crosses under normal and drought stress conditions to estimate their combining ability for grain yield and associated traits. The results showed significant correlation (mean squares) of irrigation treatment with the studied traits. The effects of parents, crosses, and genotypes were all determined to be highly significant under both irrigation levels. Grain yield and other traits showed significant differences (mean squares) associated with both General combining ability (GCA) and Specific combining ability (SCA) under both irrigation regimes, demonstrating the importance of both additive and nonadditive genetic effects in the expression of performance traits. The parental line (P-86) had positive and highly significant GCA effects, as well as the crosses (P-17×P-96), (P-8×P-96), (P-8×P-171), (P-24×P-86), (P-86×P-96), (P-86×P-171), and (P-96×P-171) which then gave the highest specific combinations under both irrigation regimes for grain yield and some of the associated traits. The highest level of heterosis (heterobeltiosis) for grain yield was obtained in the crosses (P-8×P-96), (P-8×P-137), (P-8×P-171), (P-96×P137), and (P-96×P-171) under both irrigation regimes.

In contrast to the global countries, ectomycorrhizae members are not common in Egypt, however, they are very important in the afforestation of poor lands. Their occurrence in Pinus sp., Clerodendrum sp., and Eucalyptus sp. may help to explain why these trees are the most extensively dominant around the world, especially in Egypt. The identification and characterization of numerous ectomycorrhizal fungi often involve large morphological descriptions of sporocarps alone, which consequently, in some instances, raise arguments about the accuracy of these studies. The present work was achieved to isolate, identify, and characterize three ectomycorrhizal fungi from sporocarps combining morphological and molecular techniques. The morphological characteristics of tested species were assessed and compared to standard taxonomic literature. ITS-rDNA was utilized for molecular analysis using the universal fungal primers ITS1. Identification of these species was confirmed by comparing the sequences of amplified genomes of these species with respective species sequences in GenBank, followed by blast analysis.

This study examined the macro and trace element contents as well as the cytotoxicity of Laurencia obtusa, Ulva lactuca, and Padina pavonica algae collected from the Mediterranean coast of Egypt (Alexandria coast). The results indicated that the seaweed samples contained high concentrations of Ca, Cl, Mg, K, Na, P and Fe. The Cu and Zn contents of the algae were in the ranges of 0.39-0.95 mg/100 g dw and 0.11-0.49 mg/100 g dw respectively. Fresh red algae contained the highest level of Zn and Cu, whereas the iodine level was 1.52, 1.27 and 1.01 mg/100g in fresh each of Padina pavonica, Laurencia obtuse and Ulva lactuca respectively. Fresh red, fresh green, dry green, dry red, in addition to fresh and dried brown algae had maximum lead (Pb) levels of 0.16, 0.14, 0.13, 0.12, 0.04 and 0.02 g/100 g respectively. Fresh red algae contained the highest Cd and Mn levels, whereas dried brown algae exhibited the lowest Cd and Mn concentrations. Different extracts of fresh and dried brown algae exhibited significant larvicidal activity against brine shrimp. LC50 values indicated that dry samples were more cytotoxic than fresh samples.

Tamarix nilotica is a perennial halophyte growing naturally at the Mediterranean coastal salt marshes. Vegetative parts were collected in two successive winters and summers to investigate the seasonal effects on the ecomorphological and physiological responses of T. nilotica. The results indicated that either in winter or summer seasons, T. nilotica can reduce the effect of soil salinity by excreting salts outside its body through salt glands. Summer season was characterized by low content of soil moisture (due to rare rainfall), high soil EC, high light intensity and high temperature; there-fore, plant induced certain morphoanatomical changes in leaves and stem to face the previously mentioned adverse conditions. The most remarkable changes to reduce transpiration process was found by decreasing leaf area and increasing cuticle thickness and mesophyll tissue thickness. In addition, the most marked physiological changes in summer were the significant in-crease in total phenols, proline, free amino acids and total soluble sugars. These compounds can work as osmotic regulators and/or antioxidants. These features enhance the defensive mechanism against dehydration and permit T. nilotica to tolerate the stress conditions in salt marsh habitat.

This study was conducted to investigate the effects of five essential oils (garlic, Allium sativum; camphor, Cinnamomum camphor; menthol, Mentha sp.; cinnamon, Cinnamomum erum; and clove, Dianthus sp.) on wax moth larvae and adult honeybee workers under laboratory conditions. Cinnamon, garlic, menthol, clove, and camphor oils were found to be highly effective against wax moth larvae, with 100 percent mortality achieved after 48 and 96 hours for cinnamon and garlic oils respectively, and after 120 hours for clove and mint oils. Camphor oil provided 96.60% accumulative mortality after 120 hrs. Moreover, all the essential oils were highly safe for adult honeybee workers under laboratory conditions. Accumulative corrected mortality rates after 72 hr were 15.96, 9.02, 13.18, 29.16, and 8.88% for treatments with cinnamon, clove, camphor, mint, and garlic oils respectively.

A study was carried out in a mango orchard on reclaimed land for two seasons in 2019 and 2020. The experiment was implemented on fifteen years old mango trees “Fagri Kalan” budded on seedling mango rootstock and planted at 4 × 4 m. This experiment involved two soil growth stimulants (K humate, magnetite) and foliar application with cobalt. The experiment involved two factors, the first one was soil application with K humate by two levels (50 and 100 g/tree/year) and magnetite by two levels (250 and 500 g/tree /year) plus control, whereas the second factor was a foliar application with Co as cobalt sulfate by three levels (0, 15, and 30 ppm Co). The experiment was carried out in a factorial experiment in split plot design with three replicates whereas each replicate was represented by two trees. Result indicated that soil application with K humate at 100 g/tree followed by magnetite at 250 g/tree or foliar application with Co at 15 ppm alone or the combination between (K humate at 100 g/tree and cobalt at 15 ppm) gave the highest values of yield/tree, fruit weight, TSS, reducing sugars, leaf N, P, K, and Fe content of “Fagri Kalan” mango trees grown under salinity conditions.

Two field experiments were conducted during in 2019/20 and 2020/21 seasons to study the impact of integration among mineral and nanoparticle nitrogen (N) fertilizer levels on yield traits and chemical characters of some canola genotypes grown under salt stress conditions. Four treatments of N fertilization (190 kg N/ha as recommended dose; 50% of the recommended, 95 kg N/ha+nano nitrogen (5 L/ha); 25 % of the recommended, 47.5 kg N/ha+nano-nitrogen (5 L/ha), and nano-nitrogen (rate of 5 L/ha). canola genotypes (Trabber, Agamax, and Serw4) performance were assessed under three levels of saline irrigation water (control, 2000, and 4000 mg L-1). Results showed that increasing salinity levels up to 4000 mg L-1 led to decreasing in all studied yield parameters compared with those of control (tap water). Trabber genotype excelled significantly in most of the yield characteristics. Integration between nanoscale and mineral nitrogen fertilizer, i.e. 95 kg N/ha+5 nano N L/ha) showed superiority over all applied N treatments, recording the highest values. It could be concluded that since application of 95 kg N/ha+5 nano N L/ha exploiting the nano form of N saves about 50% of applied nitrogen in canola under saline conditions. Accordingly, nanoparticles help the environmental pollution to be reduced.

The study investigated the influence of traditional nitrogen, phosphorus and potassium (NPK) mineral fertilizers and nano-fertilizers on yield, and its attributes, and fiber characters of two Egyptian cotton varieties Giza 94 and Giza 96. The design of the experiment was a split- plot with four replicates. Results indicated that Giza 94 cultivar surpassed Giza 96 in agronomic characteristics, although Giza 96 exhibited the highest fiber reading. Nano-chitosan (NPK)-fertilization significantly improved the mean value of boll weight, seed yield, lint yield, lint percentage, upper half mean (UHM), fiber uniformity index, fiber tenacity, and Micronaire value in both seasons. Conversely, the most minimal values for the aforementioned characteristics were recorded with the control NPK fertilizer over the two seasons.

The combined data from two growing seasons in a field experiment study by using two irrigation systems (surface and subsurface drip) in terms of additional water for sugar beet plants under saline conditions are used to estimate root and sugar yield, water use efficiency and root penetration power at the time of harvest. Water salinity levels of 6000 and 8000 ppm were applied to irrigate sugar beet from the time of planting on October 3 to the time of harvest on April 22 with three additions of water (limited 1750, moderate 2500 and optimum 3250 m3/fed). The results are summarized as follows: The heaviest root and highest sugar yield as well as highest water use efficiency were recorded when using subsurface irrigation system, 6000 ppm water salinity level, and moderate or optimum irrigation water (2500 or 3250 m3/fed). Oppositely, the highest penetration power values were obtained using drip irrigation systems with low water quantity (1750 m3/fed) and high-water salinity level (8000 ppm).

Soil temperature under mulching conditions has a significant impact on crop development, growth rate and other parameters. However, it is not included in the AquaCrop model. Thus, this study aims to improve the AquaCrop model performance for better simulation of soil mulches by considering the heat changing under mulch materials. The proposed modification is conducted through AquaCrop-Open Source software to identify the differences between the temperatures under the mulched soil and air temperatures. It will also help to describe them as additional heat units in specific growth stages. The field data used to evaluate the proposed model has previously been used to calibrate and validate the AquaCrop model in simulating melon growth under different irrigation treatments and soil mulching practices. The results show that the proposed model performs better than the original model in simulating mulched melon under different irrigation regimes. The root mean square error of biomass values was reduced under the modified model by 40%-75% under different irrigation treatments. Additionally, the coefficient of determination (R2) of the modified model slightly increased from the original one. Thus, the proposed model provides a more reliable and robust model.