Azospirillum brasilense and Saccharomyces cerevisiae as Alternative for Decrease the Effect of Salinity Stress in Tomato(Lycopersicon esculentum)Growth

The salinity stress is one of the most relevant abiotic stresses that affects the agricultural production.The present study was performed to study the improvement of the salt tolerance of tomato plants which is known for their susceptibility to salt stress.The present study aimed to assess to what extent strain Azospirillum brasilense(N040)and Saccharomyces cerevisiae improve the salt tolerance to tomato plants treated with different salt concentration.The inoculant strain A.brasilense(N040)was previously adapted to survive up to 7%NaCl in the basal media.A greenhouse experiment was conducted to evaluate the effect of this inoculation on growth parameter such as:plant height,root length,fresh and dry weight,fruits fresh weight,chlorophyll content,proline and total soluble sugar in tomato plants under salt stress condition.The results revealed that co-inoculation of Azospirillum brasilense(N040)and Saccharomyces cerevisiae significantly increased the level of proline(8.63 mg/g FW)and total soluble sugar(120 mg/g FW)of leaves under salinity condition comparing to non-inoculated plants(2.3 mg/g FW and 70 mg/g FW,respectively).Plants co-inoculated with adapted strain of A.brasilense and S.cerevisiae showed the highest significant(p<0.01)increase in fruit yield(1166.6 g/plant),plant high(115 cm)and roots length(52.6)compared whit un-inoculated control plants(42 g/pant,43.3 cm and 29.6 cm,respectively).In contrast,Na^(+)ion content was significantly decreased in the leaves of salt stressed plants treated with the A.brasilense(N040)and S.cerevisiae.Finally,the results showed that dual benefits provided by both A.brasilense(N040)and S.cerevisiae can provide a major way to improve tomato yields in saline soils.

Green Synthesis of Silver Nanoparticles from Abronia villosa as an Alternative to Control of Pathogenic Microorganisms

The aim of this study was to evaluate the antibacterial and antifungal activities of eco-friendly synthesized silver nanoparticles.The silver nanoparticles were synthesized by biological method using aqueous extract of Abronia villosa.Synthesis of silver nanoparticles was confirmed by color change and characterized using UV-visible spectroscopy,scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDX),dynamic light scattering(DLS),and zeta potential analysis.The SEM analysis revealed the presence of spherical silver nanoparticles of the size range 21 to 33 nm.Synthesized silver nanoparticles were used to evaluate their antibacterial effects at different concentrations(25,50,75 and 100μg/ml)on gram negative and gram positive bacteria.The biggest halo zone was observed at 75 and 100μg/ml concentrations of silver nanoparticles against both gram positive and gram negative bacteria.Antifungal activity of biosynthesized silver nanoparticles was evaluated against seven different phytopathogenic fungi.AgNPs showed high inhibition of radial growth toward all tested fungi.The highest inhibition of fungal growth by AgNPs was recorded against Macrophomina phaseolina(86.06±0.92%).Biosynthesized AgNPs using plant extract are a promising to use safety for various biomedical and agricultural applications.