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Gamma-and laser-irradiated seeds were grown under drought stress conditions to evaluate the irradiation effects on growth, flowering and some physiological traits of Salvia coccinea plants grown in pots. Pre-sowing gammairradiation at 5, 10, 15, 20 and 25 k.rad or laser irradiation (He-Ne) for 5, 10, 15 and 20 min. exposure time were applied. Soil moisture levels were imposed by irrigating the plants with 100 (control), 80, 60 and 40% of field capacity (F.C.). Results indicated that laser-irradiation was less effective than gamma-irradiation on drought stress. Plants grown under high water stress (40 and 60% F.C.) resulted in significant decreases in all vegetative growth and flowering parameters tested. The decrease in plant growth and flowering quality induced by water deficit was associated with a reduction in leaf relative water content and increases in total phenols, proline and abscisic acid contents in plants. Under water stress, there were significant changes in the activities of the defensive enzymatic system in leaves. The activities of peroxidase and catalase in irradiated plants with gamma or laser were higher at 60% F.C. than in other water stress treatments. In general, it can be concluded that initiated resistance of Salvia coccinea plants under drought stress are enhanced after pre-sowing seed irradiation with gamma at 15-25 k.rad followed by laser for 10 min. exposure time. The most effective combination was gamma-radiation (15-25 k.rad) plus soil moisture content at 80% F.C. This combined treatment protects plants from the deleterious effects of drought. It can tolerate soil water deficit and consume less irrigation water by 30%.

Foliar application effects of salicylic acid (SA) and gibberellic acid (GA 3) were investigated on growth and flowering of Ixora coccinea L. plants. Four concentrations (100, 200, 300 and 400 ppm) of both SA and GA 3 were sprayed in addition to the control (water-sprayed plants). Results indicated that all growth and flowering characteristics of Ixora plants were increased by all concentrations of SA or GA 3 compared to the untreated plants. Concerning salicylic acid, the lowest concentration (100 ppm) produced the highest plants while 200 ppm increased leaf area and shoot/root ratio. Number of leaves and plant pigments (chlorophyll a, b, a+b and carotenoids) were increased at 300ppm concentration. Spraying the plants with 400ppm increased fresh and dry weight of shoots and roots and flower number. GA 3 sprayers at 300 or 400ppm led to a significant increase in most of the characteristics studied in comparison to the untreated plants. The correlation coefficient among most of Ixora vegetative and flowering growth characteristics proved to be significant.

Stem bark aqueous extracts of eight woody plants Brachychiton populneus, Ceiba pentandra, Bombax malabaricum, Chorisia speciosa, Albizia lebbeck, Bauhinia variegata, Kigelia africana and Pinus halepensis were tested for their mutagenic and antimutagenic potential in the Ames test with Salmonella typhimurium strains TA98 and TA100. The aqueous extracts were neither toxic nor mutagenic in S. typhimurium tester strains. All of the tested extracts showed detectable antimutagenic effect towards the direct acting mutagens 2-nitrofluorene (2-NF) in TA98 as well as sodium azide in TA100. The extract from Kigelia africana was the most effective in reducing the mutagenicity caused by the direct mutagen 2-NF in the TA98 with 85.42% inhibition rate. A. lebbeck stem bark extract demonstrated the highest antimutagenic activity reducing the base substitution mutations rate for strain TA100 by 94.66% in pre-incubation assay. The results obtained showed that the stem bark aqueous extracts tested can protect cells against induced gene mutations.

To improve the salt tolerance of Genovese cultivar of sweet basil (Ocimum basilicum L.) plants, an experiment was conducted to evaluate the impact of certain growth substances (salicylic acid, seaweed extract, dry yeast and moringa leaf extract) on growth, volatile oil percentage and yield as well as chemical constituents under saline water irrigation stress conditions (control, 1000, 2000 and 4000 ppm NaCl). The obtained results revealed that the higher salinity levels (2000 and 4000 ppm NaCl) caused significant decreases in vegetative growth measurements of basil plants compared to control and the lowest salinity level (1000 ppm NaCl). Maximum reduction was observed at 4000 ppm NaCl which showed higher increase of the total phenolics and free proline contents. All recoded parameters were enhanced for plants grown under 1000 ppm NaCl. Seaweed extract was superior than other treatments in enhancing the plant tolerance to salinity which appeared in the significantly increasing of growth and volatile oil content of basil. Phenolics and proline contents were increased with salicylic acid treatment comparing with other ones. The best combination recommended as a result of the current study is treating basil plants with seaweed extract under low salinity level (1000 ppm) for improving the growth and volatile oil parameters.

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Recently, freshly aromatic herbs have a wide demand worldwide, and therefore preserving their shelf life has become an urgent matter. There are no research attempts on quality augmenting of coriander using chitosan (CS) or nano‐chitosan (CSNPs) therefore; their impacts on keeping the quality of coriander herb were examined. CS or CSNPs extended the shelf life and reduced the weight loss compared to control more so with CSNPs since it resulted in 2.3‐fold longer than uncoated herb. The imperfection of volatile oil, pigments, and protein contents detected in control was retarded by CS or CSNPs, particularly with CSNPs treatment. Contrariwise, coated herb registered lower ammonium (NH4) accumulation and CO2 production relative to the uncoated herb. The total phenolic and antioxidant capacity (DPPH) were retained in the treated herb, which decreased the membrane permeability. CS or CSNPs coatings reduced both PPO and LOX activities that prevents the herb from turning brown and therefore preserving the fresh state of the herb. Collectively, using CSNPs coating has a pronounced potential in shelf life extension of coriander herb with high visual and phytochemical quality. CSNPs can be applied in the fresh herb industry as a novel preservative to keep the quality of fresh‐cut aromatic herbs. Novelty impact statement Due to the wide demand worldwide on aromatic herbs including coriander, extending their shelf life has become an attractive matter particularly by CS and CSNPs as edible coatings. Herin, CS, and CSNPs considerably extended the shelf life and delay the weight loss of coriander herb with high visual and phytochemical quality. Therefore, CSNPs are suggested to be a novel preservative to keep the quality of fresh‐cut aromatic herbs with the assurance that these compounds are safe and environmentally friendly and do not represent a threat to their contamination.

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