The effect of synthesis nanosilver by plant extract on morphological and antioxidant properties of Artichoke (Cynara scolymus L.) under salinity stress

Salinity stress is one of the environmental factors limiting the growth of plantsand has a negative effect on their physiological processes. The harmful effects of salinity appear in plants in various ways such as death or reduction of production. Artichoke is a plant with lowdemand and resistance to salinity. The Artichoke is a perennial plant; the height of the stem is about 2 meters. Its leaves are wide, long and white in color. One of the pillars of sustainable agriculture is the use of nano fertilizersin crop ecosystems to remove or reduce the use of chemical input. Using nano fertilizers Compared to traditional fertilizerscan lead to benefits like efficiency and quality increase due to high absorption velocity, prevention of leaking waste, availability even during growth and complete absorption by plants because of appropriately fast nutrition release, reduction of plants toxicity and any other stress deriving from high concentration of local salty areas in soil, yield increase due to efficient nutrition condition of plants. Salinity stress disturbs nutritional balance in plants. Iron is one of the essential elements in plants. The balanced consumption of this element increases the yield and quality of plants.Using micronutrients through soil or sprayingimproves plant growth under stress conditions. Foliar application of elements, which prevents soil contamination, is a useful method for rapidly absorbing elements in plants.

In order to investigate the effects of salinity and nanosilver on morphological and physiological traits of artichoke, a factorial experiment was conducted in a completely randomized design (CRD) with three replications in the greenhouse of Zabul University Institute. Salinity stress in 3 levels (0, 6, and 12 mM) and nanosilver spraying in 3 levels (0, 40, and 80 mM) were considered as treatments. The nanosilver spraying was performed at seedling stage (6-8 leaves).The control was distilled water. Application of salinity stress began in the seedling stage and continued until sampling. Sampling and evaluation of the fresh weight plant, and fresh and dry weight of root were done at the beginning of the flowering. Analysis of variance (ANOVA) was performed by SAS software (version 9.1) based on all data. Then means of results were compared with LSD test at P < 0.05 level.

The main effects of salinity stress, nanosilver and their interaction on all traits were significant at 1% probability level. Maximum numbers of leaves (5 numbers), fresh weight of plant, fresh and dry weight of root (8.82, 5.93, 0.64 g per plant, respectively) and plant height were obtained by using nanosilver and lack of salinity.

Nanosilver foliar application reduced the effects of salinity and increased the physiological and morphological characteristics of Artichoke.