Pivotal impact of sources and rates of nitrogen fertilizers on yield, nitrogen use efficiency in bread wheat cultivars

Wheat is considered as one of the main agricultural cereals worldwide, used in human and animal feed. The goal of this research was to investigate the pivotal impact of using different sources and rates of nitrogen fertilizer on the productivity of wheat cultivars in two growing seasons 2015/2016 and 2016/2017 to find out alternatives for wheat farmers. A strip-split plot experimental design was used with three rates of nitrogen fertilization (119, 166 and 240 kg ha-1), three nitrogen sources (ammonium sulphate, ammonium nitrate and urea) and three wheat cultivars (Giza 168, Sakha 93 and Sakha 94). A number of variables such as number of grains spike-1, 1000-grain weight, number of spikes m-2, grain yield, harvest index, percentage of apparent recovery N of fertilizer and agronomic NUE were assessed. Results showed that Sakha 94 was superior than Giza168 and Sakha 93 in all yield-related traits. N fertilizer rate had a more consistent effect on yield-related traits. Applied 240 kg N ha-1 resulted in increased number of grains spike-1, 1000-grain weight as well as number of spikes m-2 in both seasons furthermore grain yield and harvest index, % apparent recovery N of fertilizer and agronomic NUE declined with increment of N rates. The application of sources of N fertilizer seems to play a pivotal role. Application of ammonium sulphate resulted in positive impact on all traits than other sources of nitrogen. It was concluded that grain yield enhanced by Sakha94 cultivar with 240 kg N ha-1 of ammonium sulphate

Effect of packages types and some treatments on wheat seed during storage

This experiment was conducted at the laboratory of Seed Technology Sakha Agricultural Research Station, Kafr EL-Sheikh, Egypt, during the period between 2018 and 2019 seasons. The aim of this study was to evaluate the effect of packages types and some treatments on wheat seed during storage. The experiment was designed in factorial experiment in completely randomized design with four replicates. The samples were treated with the recommended dose of malathion, recommended rate of phosphine, the powders and extracts of each of (ficus, camphor, clove), the powder of copper nanoparticles and untreated seed as a control treatment. Treated seed were stored in different packages (Jute, Plastic and Polyethylene) for 18 months. The most important results can be summarized as follows: Increasing storage periods of wheat seed up to 18 months significantly affected storage efficacy, vitality and quality of wheat seed. The best results of storage efficacy of wheat recorded when seed stored in polyethylene packages, followed by seed stored in jute packages and lastly stored in plastic packages. Seed treated with copper nanoparticles were the best in germination percentage, electrical conductivity, acidity, protein percentage, carbohydrate percentage, relative density and 1000-seed weight. While treatment with malathion was the best in acidity, relative density, 1000- seed weight and insect infestation percentage. As for phosphine, it was the best in moisture percentage, insect infestation percentage and weight loss percentage. This study recommended that treated seed with copper nanoparticles before storage and stored it in polyethylene packages under the environmental conditions of the experiment in Sakha, Kafr EL-Sheikh, Egypt

Pedigree selection in two Egyptian cotton crosses for some traits

One cycle of direct Pedigree selection was performed with selection intensity 5 % to improve productivity with accepTable fiber quality of the two Egyptian cotton ( G. barbadense L.) cross combinations. Comparing mean performance of F2 with those of F3 generation revealed increased mean values for all traits with advanced generations from F2 to F3, indicating accumulation of increasing alleles. The phenotypic variance for all traits was highly significant through F2 and F3 generations. Heritability estimates in broad sense improved considerably for all traits from F2 to advanced F3 generations. The genotypic correlation between three earliness characters was highly significant negative with most yield traits in F2 pop. I. While genotypic correlation between the previous earliness traits with yield traits in F3 generation was positively non-significant except for lint percentage that was highly significant positive. Genotypic correlation was highly significant positive among most yield and yield component traits in both generations, which helps pedigree selection to achieve high fast genetic advance. The data of the genotypic correlation among studied characters in F2 and F3 generations in population II showed highly significant negative genotypic correlation between earliness traits in F2 generation, changed to highly significant positive in F3 generation after applying pedigree selection. The genotypic correlation between most yield characters and fiber properties showed highly significant positive correlation in population II in both generations. The superior ten families in F3 generation in both populations ranked on high yield, yield components and fiber quality showed higher means than that of F2, F3, better parent and check in most yield character

Pedigree selection in two Egyptian cotton crosses for some traits

One cycle of direct Pedigree selection was performed with selection intensity 5 % to improve productivity with accepTable fiber quality of the two Egyptian cotton ( G. barbadense L.) cross combinations. Comparing mean performance of F2 with those of F3 generation revealed increased mean values for all traits with advanced generations from F2 to F3, indicating accumulation of increasing alleles. The phenotypic variance for all traits was highly significant through F2 and F3 generations. Heritability estimates in broad sense improved considerably for all traits from F2 to advanced F3 generations. The genotypic correlation between three earliness characters was highly significant negative with most yield traits in F2 pop. I. While genotypic correlation between the previous earliness traits with yield traits in F3 generation was positively non-significant except for lint percentage that was highly significant positive. Genotypic correlation was highly significant positive among most yield and yield component traits in both generations, which helps pedigree selection to achieve high fast genetic advance. The data of the genotypic correlation among studied characters in F2 and F3 generations in population II showed highly significant negative genotypic correlation between earliness traits in F2 generation, changed to highly significant positive in F3 generation after applying pedigree selection. The genotypic correlation between most yield characters and fiber properties showed highly significant positive correlation in population II in both generations. The superior ten families in F3 generation in both populations ranked on high yield, yield components and fiber quality showed higher means than that of F2, F3, better parent and check in most yield character

Experimental Behavior of Cracked Reinforced Concrete Columns Strengthened with Reinforced Concrete Jacketing

Reinforced concrete (RC) columns often need to be strengthened or rehabilitated to allow them to carry the loads applied to them. In previous studies, RC columns have been strengthened by jacketing, without considering the occurrence of cracking. In this study, the behavior of RC columns strengthened externally by jacketing after cracking is analyzed. The accuracy of the existing models was verified by analyzing the performance of fifteen RC columns with different cross-sections to determine the effect of new variables, such as the column size, amount of steel reinforcement, and whether the column was cracked or not, on the effectiveness of strengthening. The analysis demonstrated that this strengthening technique could effectively improve both the ductility and strength of RC column cross-sections. The results indicate that the model suggested by the ACI-318 code can predict the ultimate load capacity of RC columns without strengthening, or strengthened by RC jacketing before or after cracking, with higher accuracy and material efficiency. The RC columns without strengthening met the safety limit of the ACI-318 model. However, for strengthened columns, a reduction coefficient must be used to enable the columns to meet the safety limit, with values of 94% and 76% for columns strengthened before and after cracking, respectively. Furthermore, strengthening after cracking affects the ultimate load capacity of the column, with 15.7%, 14.1%, and 13.5% lower loads for square, rectangular, and circular columns than those strengthened before cracking, respectively

Stimulating the Growth, Anabolism, Antioxidants, and Yield of Rice Plants Grown under Salt Stress by Combined Application of Bacterial Inoculants and Nano-Silicon

The growth and development of rice face many issues, including its exposure to high soil salinity. This issue can be alleviated using new approaches to overwhelm the factors that restrict rice productivity. The objective of our investigation was the usage of the rhizobacteria (Pseudomonas koreensis and Bacillus coagulans) as plant growth-promoting rhizobacteria (PGPRs) and nano-silicon, which could be a positive technology to cope with the problems raised by soil salinity in addition to improvement the morpho-physiological properties, and productivity of two rice varieties (i.e., Giza 177 as salt-sensitive and Giza 179 as salt-tolerant). The findings stated that the application of combined PGPRs and nano-Si resulted in the highest soil enzymes activity (dehydrogenase and urease), root length, leaf area index, photosynthesis pigments, K+ ions, relative water content (RWC), and stomatal conductance (gs) while resulted in the reduction of Na+, electrolyte leakage (EL), and proline content. All these improvements are due to increased antioxidant enzymes activity such as catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), which decreased hydrogen peroxide (H2O2) and malondialdehyde (MDA) under soil salinity in rice plants compared to the other treatments. Combined application of PGPRs and nano-Si to Giza 177 significantly surpassed Giza 179, which was neither treated with PGPR nor nano-Si in the main yield components (number of grains/panicles, 1000 grain weight, and grain yield as well as nutrient uptake. In conclusion, both PGPRs and nano-Si had stimulating effects that mitigated the salinity-deleterious effects and encouraged plant growth, and, therefore, enhanced the grain yield

Potassium Humate and Plant Growth-Promoting Microbes Jointly Mitigate Water Deficit Stress in Soybean Cultivated in Salt-Affected Soil

Lack of high-quality irrigation water and soil salinity are two main environmental factors that affect plant development. When both stressors are combined, the soil becomes sterile and constrains plant productivity. Consequently, two field trials were designed to assess whether plant growth-promoting microbes (PGPMs; Bradyrhizobium japonicum (USDA 110) and Trichoderma harzianum) and potassium humate (K-humate) can stimulate soybean growth, productivity, and seed quality under two different watering regimes as follows: (i) well-watered (WW), where plants were irrigated at 12-day intervals (recommended), and (ii) water stress (WS), where plants were irrigated at the 18-day intervals in salt-affected soil during 2020 and 2021 seasons. Results revealed that coupled application of PGPMs and K-humate resulted in a substantial improvement in K+ levels in the leaves compared to Na+ levels, which has a direct positive impact on an enhancement in the antioxidants defense system (CAT, POX, SOD), which caused the decline of the oxidative stress indicators (H2O2, MDA, and EL%) as well as proline content under water stress in salt-affected soil. Hence, a significant increase in root length, nodule weight, soybean relative water content (RWC), stomatal conductance, photosynthetic pigments, net photosynthetic rate, soluble protein, seed carbohydrate content as well as the number of pods plant−1 and seed yield was reported. In conclusion, the combined application of PGPMs and K-humate might be recommended to maximize the soybean growth and productivity under harsh growth conditions (e.g., water stress and soil salinity)

Differences in Physiological and Biochemical Attributes of Wheat in Response to Single and Combined Salicylic Acid and Biochar Subjected to Limited Water Irrigation in Saline Sodic Soil

Given the expectancy of the water supply becoming scarce in the future and more expensive, water conservation during wheat production processes has become very crucial especially in saline sodic soil. Biochar and salicylic acid (SA) were used to assess the potential to alleviate the influences of depletion of available soil moisture (DAM) on physicochemical, physiological, biochemical attributes, as well as wheat production absorption (Triticum aestivum L. cv. Misr 1) and macro-elements. Two seasons (2018/2019 and 2019/2020) of field trials were investigated using twelve combinations of three water treatments (50%, 70%, and 90% DAM) and foliar- and soil-applied treatments (control, biochar, salicylic acid, and biochar + SA). Biochar treated plots amplified soil physicochemical attributes, leading to improved physiological traits and antioxidant enzymes, as well as yield related traits under water limitation conditions in both years. Similarly, synergistic use of biochar and salicylic acid greatly augmented the designed characteristics such as chlorophyll a, b, K+ content, relative water content (RWC), stomatal conductance, photosynthetic rate, and intrinsic water use efficiency, whilst exhibited inhibitory effects on proline content, electrolyte leakage, Na+ content SOD, POX, CAT, and MDA, consequently increased 1000-grain weight, number of grains spike−1, grain yield, as well nutrient uptake (N, P, K) under water limitation condition in both years, followed by treatment of sole biochar or SA compared to unamended plots treatment (control). Wheat productivity achieved further increasing at 70% DAM alongside synergistic use of biochar and SA which was on par with 50% DAM under unamended plots (control). It is concluded from the findings that coupled application of biochar alongside salicylic acid accomplished an efficient approach to mitigate the injurious influences of water limitation, along with further improvement of the soil, physiology, biochemical attributes, and wheat yield, as well nutrient uptake, under saline sodic soil

Application of Silica Nanoparticles in Combination with Two Bacterial Strains Improves the Growth, Antioxidant Capacity and Production of Barley Irrigated with Saline Water in Salt-Affected Soil

Exploitation of low-quality water or irrigation of field crops with saline water in salt-affected soil is a critical worldwide challenge that rigorously influences agricultural productivity and sustainability, especially in arid and semiarid zones with limited freshwater resources. Therefore, we investigated a synergistic amendment strategy for salt-affected soil using a singular and combined application of plant growth-promoting rhizobacteria (PGPR at 950 g ha−1; Azotobacter chroococcum SARS 10 and Pseudomonas koreensis MG209738) and silica nanoparticles (SiNPs) at 500 mg L−1 to mitigate the detrimental impacts of irrigation with saline water on the growth, physiology, and productivity of barley (Hordum vulgare L.), along with soil attributes and nutrient uptake during 2019/2020 and 2020/2021. Our field trials showed that the combined application of PGPR and SiNPs significantly improved the soil physicochemical properties, mainly by reducing the soil exchangeable sodium percentage. Additionally, it considerably enhanced the microbiological counts (i.e., bacteria, azotobacter, and bacillus) and soil enzyme activity (i.e., urease and dehydrogenase) in both growing seasons compared with the control. The combined application of PGPR and SiNPs alleviated the detrimental impacts of saline water on barley plants grown in salt-affected soil compared to the single application of PGPR or SiNPs. The marked improvement was due to the combined application of PGPR and SiNPs, which enhanced the physiological properties (e.g., relative chlorophyll content (SPAD), relative water content (RWC), stomatal conductance, and K/Na ratio), enzyme activity (superoxide dismutase (SOD), catalase (CAT), and peroxidase (POX)), and yield and yield-related traits and nutrient uptake (N, P, and K) of barley plants. Moreover, the Na+ content, hydrogen peroxide (H2O2) content, lipid peroxidation (MDA), electrolyte leakage (EL), and proline content were reduced upon the application of PGPR + SiNPs. These results could be important information for cultivating barley and other cereal crops in salt-affected soil under irrigation with saline water

Collaborative Impact of Compost and Beneficial Rhizobacteria on Soil Properties, Physiological Attributes, and Productivity of Wheat Subjected to Deficit Irrigation in Salt Affected Soil

Plant growth and crop productivity under unfavorable environmental challenges require a unique strategy to scavenge the severely negative impacts of these challenges such as soil salinity and water stress. Compost and plant growth-promoting rhizobacteria (PGPR) have many beneficial impacts, particularly in plants exposed to different types of stress. Therefore, a field experiment during two successive seasons was conducted to investigate the impact of compost and PGPR either separately or in a combination on exchangeable sodium percentage (ESP), soil enzymes (urease and dehydrogenase), wheat physiology, antioxidant defense system, growth, and productivity under deficient irrigation and soil salinity conditions. Our findings showed that exposure of wheat plants to deficit irrigation in salt-affected soil inhibited wheat growth and development, and eventually reduced crop productivity. However, these injurious impacts were diminished after soil amendment using the combined application of compost and PGPR. This combined application enhanced soil urease and dehydrogenase, ion selectivity, chlorophylls, carotenoids, stomatal conductance, and the relative water content (RWC) whilst reducing ESP, proline content, which eventually increased the yield-related traits of wheat plants under deficient irrigation conditions. Moreover, the coupled application of compost and PGPR reduced the uptake of Na and resulted in an increment in superoxide dismutase (SOD), catalase (CAT), and peroxidase (POX) activities that lessened oxidative damage and improved the nutrient uptake (N, P, and K) of deficiently irrigated wheat plants under soil salinity. It was concluded that to protect wheat plants from environmental stressors, such as water stress and soil salinity, co-application of compost with PGPR was found to be effective