An efficient and promising protocol for in vitro propagation of Zingiber officinale Rosco using sprouting buds was established. Sprouting buds were sterilized and cultured onto MS medium supplemented with different growth regulators. Augmentation of MS-medium with 4.5mg/l BAP recorded the highest percentage of shootlets multiplication. Shootlets were highly rooted on half strength of B5 medium supplemented with 1.0mg/l NAA. The maximum percentage of acclimatization, hardening and rhizomes production of in vitro derived plants in greenhouse was 80–100%

A multiresidue method was studied for determination of 323 pesticides representing a wide range of physicochemical properties in dry herbs (chamomile and parsley) based on QuEChERS method and LC-ESI-MS/MS analysis. In the current study, three different parameters were optimised for a higher accuracy and a lower matrix effects: extraction procedures, cleanup and matrix effect. Optimum extraction efficiency was obtained at sample hydration of 10 mL water on 2 g dry herbs and soaking time for 10 min. Use of different extraction techniques supported the use of mechanical shaker in comparison with ultrasound and handed shaking. As a way to remove interfering components from final extract, different cleanup techniques were studied: three dispersive solid phase extraction (D-SPE) (C₁₈, primary secondary amine and graphitised carbon black) have been investigated; matrix effect was reduced, but several pesticides were lost during the cleanup process. Unlike the SPE (hydrophilic lipophilic balanced polymer) produced a good recovery with all substances without expected reduction in matrix effect. Moreover, sample dilution and LC-MS/MS injection volume were studied, 3 µL injection volume was found to be the best sensitive condition without sample dilution. The developed method was validated by performing recovery tests at 0.01, 0.05 and 0.1 mg/kg, the average recoveries ranged from 70% to 120%. The reproducibility expressed as relative standard deviation (RSD %) was ≤ 20%.

Drought stress is seriously affecting maize production. To investigate the influence of calcium (Ca) foliar application on maize production and chemical composition of grains under drought stress, two experiments were carried out at Cairo University Research Station, Giza, Egypt, during the summer seasons of 2018 and 2019. The experimental design was split-split plot design with a completely randomized blocks arrangement with three replications. Water regimes were assigned to the main plots [100 (control), 75, and 50% of estimated evapotranspiration]. Calcium levels (zero and 50 mg/L) were assigned to the sub plots. Maize cultivars (SC-P3444, Sammaz-35 and EVDT) were assigned to the sub-sub plots. Three maize cultivars were sprayed with Ca solution concentration (50 mg/L) under normal and drought conditions. The control treatment (0 mg/L) was sprayed with an equal amount of distilled water for comparison. Results indicated a significant decrease in total yield and grain characteristics [protein, ash, total sugars, nitrogen (N), phosphorus (P), potassium (K), and iron (Fe) contents] as a response of drought. Calcium foliar application significantly increased maize yield, protein, ash, carbohydrates, starch, total sugars, and ionic contents of grains, except for manganese (Mn), under all irrigation levels. Based on the drought tolerance index (DTI), only cultivar SC-P3444 showed drought tolerance while cultivars Sammaz-35 and EVDT were sensitive to drought stress. Foliar application of Ca on SC-P3444 cultivar achieved the highest grain yield per hectare (8061 kg) under the water regime of 100% of the total evapotranspiration, followed by Sammaz-35 (7570 kg), and EVDT (7191 kg) cultivars. At the water regime of 75% of estimated evapotranspiration (75% irrigation), Ca foliar application increased grain yield by 16, 13 and 14% in SC-P3444, Sammaz-35, and EVDT, respectively. At the water regime of 50% of the estimated evapotranspiration (50% irrigation), Ca foliar application increased grain yield by 17, 16, and 13% in SC-P3444, Sammaz-35, and EVDT, respectively. In brief, Ca had a clear impact on productivity and grain quality with important implications for maize yield under normal and water stress conditions. Our findings demonstrate that foliar application of Ca enabled drought stressed maize plants to survive better under stress. The most water stress tolerant cultivar was SC-P3444 followed by Sammaz-35 and EVDT under drought stress.

Abiotic stresses in sandy soil, which include saline water, saline soil, and lack of nutrients, affect the productivity and quality traits of peanuts (Arachis hypogaea L). Elemental calcium (Ca²⁺) is necessary for the proper development of peanut pods. This work aimed at comparing conventional Ca and nano-Ca form effects on peanut production and quality traits. Two randomized complete block field experiments were conducted in the 2015 and 2016 seasons. Treatments were control, gypsum plus calcium nitrate Ca(NO₃)₂, Ca(NO₃)₂, and chelated calcium, as well as 100, 75, 50, 25, and 12.5% of Ca(NO₃)₂ doses in a nano form. The results indicated that the treatment of gypsum plus conventional CaNO₃ achieved the highest yield and best quality traits, followed by the Ca(NO₃)₂ and 100% nano Ca(NO₃)₂ treatments. The treatments of the control, gypsum, and 12.5% nano Ca(NO₃)₂ had the lowest effect on peanut performance. The conventional treatment of gypsum plus Ca(NO₃)₂ resulted in the greatest seed yield (1.6 ton ha⁻¹), oil yield (700.3 kg ha⁻¹), and protein yield (380.1 kg ha⁻¹). Peanuts may benefit from Ca²⁺ better by using gypsum as the soil application and calcium nitrate as the foliar application to prevent disorders of Ca²⁺ deficiency under sandy soil conditions.