الفهرس 
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Abstract
Two pot experiments were carried out at the Experimental Farm and laboratory of Agricultural Botany Department, Faculty of Agriculture, Mansoura University, Egypt (31°02’40.6”N latitude, 31°22’40.3”E longitude and the altitude is 12m above the sea level), during the two growing seasons of 2015 and 2016. These experiments aimed to investigate the ameliorative effect of zeolite as a soil addition or chitosan as a foliar application on rosemary plants grown under salt stress condition. The most important results are summarized as follows : Sodium chloride up to 7.5 dSm-1 caused a significant decline in Rosemary plant growth represented as plant height and root length, shoot and root fresh and dry weight as well as number of branches per plant. Application of either chitosan or zeolite significantly increased Rosemary growth parameter as plant height and root length, shoots fresh and dry weight as well as number of branches per plant as compared to the control. The most effective level in this concern was zeolite at 8 g/kg. Application of zeolite increased significantly plant height and root length, shoot and root fresh and dry weight as well as number of branches per plant under moderate salinity level (5 dSm-1) compared with untreated plant. Meanwhile, under severe salinity level, application of either zeolite or chitosan in most cases mitigated the harmful injuries of salinity on plant growth as compared with untreated plants. Photosynthetic pigments markedly reduced with increasing salinity levels in both seasons. The greatest decline was obtained under high salinity level (7.5 dSm-1). The ratio between chlorophyll a and chlorophyll b was reduced in the first season and enhanced in the second season compared to control plants. Under control, using of either chitosan or zeolite in most cases significantly increased photosynthetic pigments concentration compared with untreated control plants. However, application of chitosan or zeolite reduced chlorophyll a:b ratio in the 2nd season, whereas increased it in the 1st season. Application of either chitosan or zeolite mitigated the injuries of salinity on photosynthetic pigment concentration. Salinity stress caused disturbance in the electrolyte balance. Sodium percentage and chloride concentration were increased with salinity. This increase was accompanied by a decrease in nitrogen, phosphorous, potassium and K+/Na+ ratio in both shoot and root system. The great reduction occurred under high salinity levels compared with control plants. Application of either zeolite or chitosan, significantly increased in most cases the K+/Na+ ratio, nitrogen, phosphorous and potassium percentage, but decreased the percentage of sodium and chloride concentrations in both shoot and root systems during the two experimental seasons. Additionally, they counteracted the injury’s impacts of salinity on minerals either in the shoot and root systems. Salinity levels, application of either zeolite or chitosan as well as their interactions induced proline concentration in both shoot and root systems of rosemary plants in both growing season. Total soluble carbohydrates concentration in both shoot and root systems of rosemary were significantly increased with an increase in either salinity level or application of each chitosan or zeolite and their interactions in both shoot and root samples in the first and second season. Salinity up to 7.5 dSm-1 significantly increased ascorbic acid concentration. Similarly, application of either zeolite or chitosan at both concentration and their interaction with salinity, increased this parameter. Total soluble phenols concentration in shoot system of rosemary plants was significantly increased with increasing salinity levels up to 7.5 dSm-1 ; and or application of either zeolite or chitosan at both concentrations. Salinity decreased the RWC in both season and WC in the second season as compared with control. Application of either chitosan or zeolite significantly increased the relative water content and water content percentage of rosemary plants compared with untreated plants in both season respectively. Additionally, either chitosan or zeolite treatment recorded higher RWC compared to the control. Membrane permeability percentage significantly increased with increasing salinity stress up to 7.5 dSm-1, meanwhile, chitosan or zeolite treatments, significantly decreased membrane permeability percentage. The interaction treatments counteracted the harmful effect of salt stress as compared with control. Salinity stress has a negative impact on most leaf anatomical characters. The reduction values were obtained in thickness of rosemary leaf blade thickness, medrib region dimension, and main vascular bundle dimension. The dimension of midrib region and leaf blade, and dimension of the main vascular bundle were increased as a result of chitosan or zeolite application. Chitosan or zeolite in combination with salinity stress level significantly increased, most leaf anatomical features compared with untreated plants under the same salinity level. Salt-stressed plants characterized by a small number of chloroplasts comparing with control or chitosan or zeolite treated plant cells. However, chitosan or zeolite treatment counteracts the aforementioned maladies induced by salinity stress, as reduced the intercellular spaces and increased the cell organelles as compared with untreated salinity affected plants. Application of zeolite at 4 g/kg soil under salinity induced an excessive accumulation of dense bodies in the cytoplasm as compared with other treatments. Salinized plants showed drastic changes, including a striking disruption of chloroplasts and appeared to be severely swollen and irregularly shaped with a partly disorganized membrane system and deterioration of thylakoid membranes. The grana lamella structure was evacuated and distortion. Their thylakoid membranes showed dilations. Salinity stress distorted the chloroplasts structure. In addition no starch granules were produced in the chloroplast stroma. Salt stress led to plastoglobules with an increased size and electron density in chloroplast stroma. chitosan or zeolite treatments under normal condition showed a typical chloroplast ultrastructure with no or less significant changes, except, the appearance of starch grain in the chloroplast. However, these treatments under severe salinity stress alleviated the damage and thus the chloroplasts ultrastructures were elongated in shape, having organized thylakoid membrane system, clearly differentiated into grana stacks, relatively starch grains were observed as well as a well organized plastoglobuli. Alternatively zeolite at 8 g/kg soil under salinity declined the number and size of plastoglobuli in chloroplasts. Salinized condition showed a distortion of the cell nucleus, the nucleus was misshapen and appeared small in its volume as compared with control treatment. The chromatin was declined and the nucleus appeared as a light colour. chitosan or zeolite treatments protected the nucleus from and degradation or changes as compared with salt stressed plants, the chromatin materials were distributed ordinarily in the nucleus. Increasing salinity levels significantly increased essential oil percentage accompanied with a decrease in oil yield per plant, especially under high salinity. Either chitosan or ziolite application at both concentration examined significantly increased essential oil percentage and essential oil yield. Using of either zeolite at both concentrations under all salinity levels significantly increased essential oil percentage and yield as compared with control plants. However chitosan at 250 mg/l under severe salinity stress significantly increased the essential oils as compared with control plants.