The effect of magnetic water compared with saline water , nano-Mg at 100 and 200 ppm and nano-Zn at 50 and 100 ppm treatments and their combinations on lemongrass plants (Cymbopogen citratus L.) was studied during 2018/2019 and 2019/2020.Vegetative growth parameters including plant height, number of tillers/ plant, leaf area, herb fresh and dry weights were greatly affected by both studied factors. Magnetic water treatments recorded the highest values of all vegetative growth parameters compared with saline water. However, all nanoparticles of Mg and Zn treatments were superior than control in promoting vegetative growth parameters and the treatments of 100 ppm nano-Zn and 200 ppm nano-Mg recorded the maximum values of vegetative growth parameters. The combined treatments showed that the highest values of vegetative growth measurements were obtained in plants irrigated with magnetic water and sprayed with 100 ppm nano-Zn, in both cuts In 1st and 2ndseasons.N, P, K and Mg contents were significantly higher in lemongrass plants irrigated with magnetic water than those irrigated with saline water. Moreover, the treatments of 100 ppm nano-Zn exhibited the highest significant values of N, P, K, whereas 100 and 200 ppm of nano-Mg treatments were superior in recording the highest values of Mg content, in the two seasons. The combination treatments of lemongrass plants irrigated with magnetic water and sprayed with 100 ppm nano-Zn or 200 ppm nano-Mg produced the richest values of N, P and K% D.W., whereas, the treatments of magnetic water combined with 100 or 200 ppm of nano-Mg produced the best Mg content.A great effect of magnetic water irrigation on increasing Fe and Zn contents than saline water treatments. The treatments of 50 and 100 ppm of nano-Zn were more effective than control and other treatments in maximizing Fe and Zn levels. The combined treatments of lemongrass plants irrigated with magnetic water and sprayed with 100 ppm of nano-Zn exhibited the highest values of Fe and Zn% D.W. in most cases. Additionally, total chlorophyll greatly increased in lemongrass plants irrigated with magnetic water than those irrigated with saline water, whereas the treatment of 200 ppm nano-Mg increased it than others. Interaction effect showed that, plants irrigated with magnetic water and sprayed with nano-Mg at 200 ppm exhibited the highest values of total chlorophyll.Proline and glycine betaine contents were greatly decreased with magnetic water treatment compared with saline water. Meanwhile, all applied treatments were effective in decreasing the levels of both constituents than control, which considered a good indicator to alleviation of water salinity stress on lemongrass plants through magnetic water and nanoparticles of Mg and Zn applications. Finally, volatile oil %, was greatly increased in lemongrass plants irrigated with magnetic water, especially the treatment of nano-Zn at 100 ppm as compared of others in this respect in both cuts and the two studied seasons. The interaction between the two studied factors was significant which means that both factors act together in improving volatile oil content in lemongrass herb

The honey dew moth Cryptoblabes gnidiella Milliere is one of the most important insect pests of stored garlic. Data revealed that, Egyptian (Baladi) cultivar was the least susceptible to attacke by this insect . After four months of storage, the infestation percentages were 21.68% for Egyptian (Balady) cultivar as compared to 32.39% for Sids 40, 44.88% for American and 70.99% for Chinese cultivar. The oil content of the four garlic cultivars were measured along four months of storage. Data showed that the four cultivars were differed significantly in this respect. The highest weight of volatile oils, 436.8 mg/100g was fined in the Egyptian cultivar whereas the Chinese cultivar had 340.6 mg/100g. The correlation coefficients “r” values showed highly significant and negative relationship between infestation percentages and volatile oils weight (mg) . The main components of the volatile oils of the tested four garlic cultivars were separated by GC- MS analysis. Nine sulfur compounds were separated and identified, the major compound was Diallyl trisulfide (i.e. 49.82, 46.23, 46.17 and 44.89%) for Egyptian, Sids 40, Chinese and American cultivars, respectively. Allyl methyl trisulfide ranged from 11.40 to 23.15%. On the other hand percentage of total soluble solids (TSS%) for the four cultivars were almost the same trend during the storage period extended for four months or slightly increased. These data indicate the importance of the type and quantity of volatile oils and its component in protection of stored garlic from infestation by C. gnidiella.

The present work aimed to investigate the stimulating and attractive effects of five volatile oils on honey bee colonies food consumption. These oils were added to sugar syrup and pollen substitutes. The consumption of sugar syrup and percentage of dead bees in caged honeybee work-ers were determined. Multi-choice test inside the honey bee colonies was carried out to determine the food consumption rate from different pollen substitutes. Positive effect was recorded by adding Coriander oil 0.03% followed by Fennel 0.15% and Spearmint oils 0.03% while nigella oil showed a repellent effect on honey bee workers. The mor-tality percentage was very low with no significant differences between treatments. Results indicated that addition of 5% pollen grains and three volatile oils increased significantly pollen substitute’s con-sumption. The highest consumption rate was rec-orded with coriander oil 0.03%. Results obtained indicated that the consumption of diets that con-tain Coriander, Fennel, and Spearmint volatile oils was more successful than control.

Eight most currently used antibiotics were examined for their antibacterial properties against Gram-ve bacteria as Pseudomonas aeuroginosa, E. coli, Proteus vulgari and Gram+ve as Staphylococcus aureus, Streptococcus pneumonia. Nitrofurantoin was the most effective against the tested bacteria, the inhibition zones ranged between 16-20mm and the MIC between 65-85ug/ml followed by ampicillin (11-18mm), ciprofloxacin (9-12mm) and gentamicin (6-9mm). The erythromycin was the lowest effective against the tested bacteria. Also, seven volatile oils were applied by contact and fumigation methods to study their effect on the tested bacterial strains. The fumigation method gave the highest inhibitory effect more than contact method and the thyme oil gave maximum inhibitory action (inhibition zone 20-28mm) against all the tested bacteria, and the MIC ranged between 0.1-0.15mg/ml followed by marjoram oil (19-25mm) and the MIC between 0.1-0.2mg/ml, cinnamon oil (12-16mm) and the MIC between 0.2-0.3mg/ml. Anise and chamomile oils did not gave any response against all the tested bacteria. The combination between thyme and other tested oils gave a synergistic effect for inhibitory action against all the tested bacteria, if compared with thyme oil alone. The combination between thyme and marjoram oil gave the maximum inhibition zones (20-29mm), followed by thyme with cinnamon oil (20-27mm), thyme with geranium gave (18-27mm), thyme with peppermint (17-27mm), thyme with chamomile (16-27mm) and thyme with anise oil (15-26mm). The combination of thyme oil with different tested antibiotics gave the lowest inhibitory effect than combination between thyme and other volatile oils against all the tested bacteria. The protein and DNA content of treated bacteria with thyme oil were increased by 38.46-47.37% and 34.26-46.94% respectivily, if compared by non-treated bacteria