Applying partial root drying drip irrigation in the presence of organic mulching. Is that the best irrigation practice for arid regions? Field and modelling study using the saltmed model

This research aimed at investigating the impact of irrigation systems, a deficit irrigation strategy and organic mulching using rice straw on maize water productivity in Egypt's arid conditions. The field experiment included 16 treatments over 2 seasons, 2015 and 2016. Irrigation systems were a drip irrigation system (DIS) and a furrow irrigation system (FIS), while the irrigation strategies were 100% full irrigation (FI), 75% FI, 50% FI and partial root drying (PRD). Organic mulching using rice straw (OMRS) was also investigated. The experimental results indicated that there was a positive impact of applying a PRD strategy by drip irrigation in the presence of organic mulching on the yield (12.6 t ha‐1 for 2015 and 12 t ha‐1 for 2016) and on the water productivity of maize (4.81 kg m‐3 for 2015 and 4.58 kg m‐3 for 2016), but under the control treatment (FIS with 100% full irrigation and without organic mulching) yield was 7.22 t ha‐1 for 2015 and 7.34 t ha‐1 for 2016 and water productivity of maize was 0.64 kg m‐3 for 2015 and 0.62 kg m‐3 for 2016. The SALTMED model simulated reasonably well the soil moisture and salinity distribution as well as maize dry matter, yield and water productivity for all treatments, with R2 of 0.998, 0.997 and 0.996, respectively. The results support the use of a PRD strategy by a drip irrigation system accompanied by an organic mulch of rice straw instead of the commonly used furrow irrigation. The PRD would save more fresh water, achieve higher yields and water productivity. In addition, mulching would reduce evaporation losses, retain soil moisture and increase organic matter content

RESPONSE OF TWO CANOLA VARIETIES (Brassica napus L.) TO NITROGEN FERTILIZER LEVELS AND ZINC FOLIAR APPLICATION

Two field experiments were carried out at the Agricultural Experimental Station of the National Research Center at Shalakan, Qalubeia Governorate, Egypt, during the two successive winter seasons of 2005/2006 and 2006/2007 to study the response of some canola varieties (Topas and Pactol cvs.) to nitrogen fertilizer levels (20, 40 and 60 kg N/faddan, (faddan = 4200 m2)) and number of zinc foliar application, one zinc foliar application (rosette stage) or two zinc foliar applications (rosette and bud stages). Concerning varitial differences, the obtained results illustrate that no significant differences between both varieties on the most studied characters, except for plant height and seed yield/faddan where, Pactol superior in plant height, 1000-seed weight, seed yield /plant, seed yield /faddan and oil yield /faddan. Increasing nitrogen fertilizer from 20 to 60 kg N/faddan significantly increased plant height, number of siliqua/plant, seed yield /plant, seed yield /faddan and oil yield/faddan. Most of studied characters were significantly increased by increasing number of zinc foliar application where, two zinc foliar application significantly affected in plant height, number of siliqua /plant, seed yield/ plant, seed yield /faddan and oil yield/faddan. The interactions between different factors show significant differences in the most studied characters

Egyptian Citrus Essential Oils Recovered from Lemon, Orange, and Mandarin Peels: Phytochemical and Biological Value

Citrus peels are an important by-product of citrus processing industries, but a large part is considered waste. There has been increased attention in the last five years on these industrial by-products, especially those containing residual essential oils (EOs). Lemon, orange, and mandarin peels from Egypt were subjected to hydro-distillation to obtain EOs, which were analyzed via mass spectrometry (GC/MS) and by building Global Natural Products Social Molecular Networking (GNPS-MN) for the purpose of visually exploring the volatile components of citrus species. The constructed MN revealed that D-Limonene, α-pinene, and β-pinene are the dominant volatile constituents in the three Egyptian citrus species. The EOs from three citrus peels exhibited promising activities as antioxidants using two tested methods: 1,1-diphenyl-2-picryl-hydrazil (DPPH) and nitric oxide (NO) compared with vitamin C. Lemon EO proved excellent antimicrobial activity against Gram-positive and negative bacteria. Additionally, the three citrus EOs showed good activities against the yeast Candida albicans. Regarding the anti-inflammatory assay, the three citrus EOs showed promising activities as COX-1 and COX-2 inhibitors. This study concludes that EOs extracted from citrus peel waste can be valorized as an innovative strategy for food preservation or may be incorporated in cosmetics and pharmaceutical formulations in alignment with circular economy principles

Innovative Processing Technologies to Develop a New Segment of Functional Citrus-Based Beverages: Current and Future Trends

The food industries are interested in developing functional products due to their popularity within nutritional and healthy circles. Functional fruit-based beverages represent one of the fast-growing markets due to the high concentrations of bioactive compounds (BCs), which can be health promoters. Hence, functional beverages based on citrus fruits are a potential way to take advantage of their nutritional and bioactive properties that could attract the interest of consumers. In order to ensure microbial and quality stability, the beverages are subjected to preservation treatment; however, the application of high temperatures leads to the loss of thermolabile BCs. Nowadays, innovative processing technologies (IPT) such as pulsed electric field (PEF), high-pressure processing (HPP), ultrasound processing (US), ohmic heating (OH), and microwave (MW) are a promising alternative due to their efficiency and low impact on juice BCs. The available literature concerning the effects of these technologies in functional fruit-based beverages is scarce; thus, this review gathers the most relevant information about the main positive and negative aspects of the IPT in functional properties, safety, and consumer acceptance of functional citrus-based beverages, as well as the use of citrus by-products to promote the circular economy in citrus processing