Samira A. F. El-Okkiah

Paclobutrazol (PBZ) is a plant growth retardant used to regulate plant architecture and might improve seedlings quality and plant productivity. This study evaluated the effects of PBZ concentration and application timing on seedling growth, physiological and biochemical responses, anatomy, and subsequent field productivity of pepper (Capsicum annuum L.). A commercial pepper cultivar was treated with PBZ at 0, 15, 30, and 60 mg L⁻¹ at the first, second, or third true-leaf stage during two growing seasons (2022 and 2023). Application of the PBZ significantly reduced seedling height while increasing stem diameter and SPAD values at seedling stage. In contrast, shoot dry weight decreased from 0.35 and 0.33 g in controls (untreated plants) to 0.26 and 0.27 g under 30 mg L⁻¹ PBZ. In addition, PBZ application enhanced antioxidant activity, particularly peroxidase, which increased from 0.057 in untreated seedlings to 1.69, 1.92, and 1.95 at 15, 30, and 60 mg L⁻¹, respectively. Anatomically, PBZ increased leaf lamina thickness and vascular tissue development in leaves and stems. Interestingly, PBZ increased chlorophyll content, leaf and branch numbers, biomass, and fruit yield, but increasing PBZ above 30 mg L⁻¹ provided limited additional benefit and tended to reduce yield at 60 mg L⁻¹. Overall, optimizing PBZ application (concentration and timing) might provide better seedling quality and subsequent field and yield performance in pepper.

The harmful impacts of ozone (O₃) on plant development and productivity have been excessively studied. Furthermore, the positive influences of its low concentrations still need to be explored further. The present study was performed to assess the impact of low concentrations of O₃ on two sweet pepper hybrids under cold stress. The ozonated water was utilized for seed soaking or foliar application at concentrations of 0, 10, 20, 30, and 40 ppm. Seed soaking using ozonated water for 1 h was compared to soaking in distilled water as a control. Moreover, exogenously ozonated water was sprayed thrice at three-day intervals compared with untreated control. The differences between the applied methods (seed soaking and foliar application using ozonated water) were not statistically detected in most of the evaluated parameters. On the other hand, the evaluated hybrids displayed significant differences in the studied parameters, with the superiority of the Lirica evident in most germination and seedling growth parameters. Both applied methods significantly improved germination and seedling growth parameters. In particular, the concentration of 40 ppm displayed the highest enhancement of the germination index, coefficient velocity, and seedling quality. In addition, it promoted the seedling maintenance of high relative water content (RWC), chlorophyll, proline, and ascorbate peroxidase activity under cold stress conditions. Moreover, it protected the cell wall from damage by decreasing membrane permeability (MP). Generally, the best results were obtained from 40 ppm followed by 30 ppm of O₃ as seed soaking or foliar spray. The results pointed out the possible use of O₃ in a low concentration to protect the plants from cold stress during germination and early plant growth.

Rice is one of the most important crops in Egypt. Due to the gap between the demand and the availability of the local edible oils, there is need to raise the nutritional value of rice and, therefore, to improve the nutritional value of the consumer. This research was carried out at the Experimental Farm of Sakha Agricultural Research Station, Sakha, Kafr El-Sheikh, Egypt, during the 2019 and 2020 seasons. Five newly developed genotypes of rice, namely NRL 63, NRL 64, NRL 65, NRL 66, and Giza 178 as check variety (control), were used to evaluate the analytical characterization of raw rice bran and rice bran oil from rice bran, study the genetic variability and genetic advance for various quantitative and qualitative traits in rice as well as, rice bran oil. The genotypes were evaluated in a randomized complete block design (RCBD) with three replications. Analysis of variance revealed highly significant variations among the genotypes for all the studied characters. Data revealed that high estimates of the phenotypic coefficient of variance (PCV%) and genotypic coefficient of variance (GCV%) were observed for amylose content percentage, peroxide value (meq/kg oil), myristic C14:0, and arachidic C20:0, indicating that they all interacted with the environment to some extent. The line NRL66 and NRL64 showed the highest and high values of mean performance for grain yield (t/h), grain type (shape), amylose content percentage, crude protein, ether extract and ash of milled rice, crude protein, ether extract, ash, phosphorus, magnesium, manganese, zinc, and iron of stabilized rice bran oil. Genetic advance as a percentage of mean was high for most of the studied traits. It indicates that most likely, the heritability is due to additive gene effects, and selection may be effective. The percentage of advantage over the Giza 178 as the commercial variety was significant and highly significant among the genotypes for all the characters studied in the two years, indicating that the selection is effective in the genetic improvements for these traits.

Two pot experiments were conducted under greenhouse conditions to study the effect of sewage water on growth, leaves pigments, certain biochemical composition, yield and anatomical of faba bean plants. These experiments were performed in the Department of Agricultural Botany, Faculty of Agriculture, Kafrelsheikh University, during two successive seasons of 2013/2014 and 2014/2015. Faba bean (V. faba L.; cv. Sakha 1) was obtained from Food Legumes Research Section at Sakha Agriculture Research Station (SARS). The experiments were arranged in a factorial arrangement, with three levels of sewage water were diluted with tap water to give 25, 50 and 100% in addition to 0% used in irrigation. The main obtained results will be summarized as follows sewage water at 25% concentration significantly increased plant height, number of branches/plant, leaf area, dry weights of root and shoot while sewage water at 100% concentration significantly decreased the same characteristics at 60 and 75 days after sowing in both seasons compared with control plants. Maximum total number of flowers/plant was resulted from low concentration of sewage water (25%Sw). There are increases on the number of flowers at all days of flowering period after sowing compared with control plants in both seasons. There was a decrease for total number of flowers/plant from using (50%Sw) and (100%Sw). Application of sewage water in faba bean plants with low (25%Sw)concentration significantly increased number of pods/plant, number of seeds/pod, weight of 100 seeds g., and seed yield g /plant compared with control plants. While the highest concentration of sewage water (100%SW) significantly decreased above mentioned characters compared with control plants in both seasons. The treatment of sewage water (Sw 25%) significantly increased chl.a, chl. b, and total chl. compared with control plants. Chlorophyll pigment of faba bean leaves were decreased as sewage water concentration increased (100%Sw). Data also showed N, P and K percentages significantly increased in shoot under lower concentration of sewage water (Sw 25%) irrigation, while Zn and Fe concentration significantly decreased in shoot in both seasons compared with control plants. The highest concentration of (100% SW) gave significant decrease for N, P and K percentages in faba bean shoot, in the same time, this treatment caused significant increase for Zn and Fe percentages comparing to control plants. Heavy metals (Cd and Pb) in faba bean plant organs (root, shoot and seeds) significantly increased as increasing heavy metals concentration in sewage water content of heavy metals (Cd and Pb) was found in root followed by shoot and seeds. Using sewage water in irrigation faba bean plants at 25% and 50% concentration significantly increased protein and total carbohydrates content in seed in both seasons compared with control plants. Application of sewage water in at 100% concentration significantly decreased seed content of protein and total carbohydrates in both seasons compared with control plants. Anatomical characteristics measurements of faba bean root and stem were affected by all concentration of sewage water irrigation, sewage water at 100% gave the lowest values of diameter thickness of cortex tissue, diameter of xylem vessel, and these decreases were significant compared with the control. Analysis of fluorescence revealed lignin deposit in the Epidermis cells that was observed in the treatment exposed to the highest level of sewage water. abaxial epidermis of faba bean leaves showed slightly elongated cells irregular in shape with reduced size at the higher concentrations of sewage water treatment.