Response of Lemongrass Plants to Magnesium Nanoparticles Loaded on Chitosan under Sandy Soil Conditions

Abstract

An experiment was conducted during 2017/2018 and 2018/2019 seasons to evaluate the response of Cymbopogon flexuosus L. and Cymbopogon citratus L. lemongrass plants to spraying of Chitosan either alone or loaded with magnesium nanoparticles under Siwa Oasis region conditions. The treatments were control, chitosan 0.2%, chitosan + 0.1 g/L magnesium nanoparticles, chitosan + 0.2 g/L magnesium nanoparticles and chitosan + 0.3 g/L magnesium nanoparticles. Plant height (cm), fresh and dry weights/ plant (g), estimated fresh and dry weights (kg) /fed., total chlorophyll (reading) and Mg % were recorded. However, volatile oil attributes including volatile oil %, volatile oil content/ plant (ml) and estimated yield of volatile oil per fed. (L) were determined. However, volatile oil constituents resulted from the used treatments in both species of lemongrass was also determined in the first season. The great effect on studied measurements were obtained with chitosan loaded with 0.3 g/L Mg nanoparticles, however, all used treatments were recorded higher values than control. Sometimes the treatment of chitosan + 0.2 g/L Mg exhibited similar values to those obtained in chitosan + 0.3 g/L Mg especially in fresh weights per plant or per fed. On the other hand, C. flexuosus L. was superior than C. citratus in most measurements except fresh weights values where they exhibited similar values in the first cut but C. flexuosus was superior in the second cut. The treatments of chitosan loaded with 0.3 g/L nano Mg exhibited higher values of Mg and this finding was correlated with higher values of volatile oil %, volatile oil yield/plant (ml) and yield of volatile oil per fed. (liter). However, C. citratus was superior than C. flexaosus in Mg content and consequently in volatile oil production. Data also showed that the volatile oil attributes were decreased in the second cut than in the first one. Regarding volatile oil fractions, data showed that the main component was Citral in both species of lemongrass. The used treatments greatly affected volatile oil fractions than control. Generally, it could be extracted that the higher volatile oil fractions values in C. flexuosus were Citral, Benzene methoxy, Geranyl acetate, Octane dimethyl and Hydroxy methylpropyl. However, in C. citratus the main components were Citral, Myrcene, Geraniol, Bicyclo heptan and Linalool oxide.