Vermicompost leachate reduces some negative effects of salt stress in pomegranate

Abstract Purpose Growth and productivity of plant crops are negatively affected by salt stress. Vermicompost leachate (VCL) has beneficial effects on plant growth in several different ways. This experiment was conducted to investigate the potential of VCL for raising the tolerance of pomegranate against salinity. Methods A pot experiment was organized to analyze some physiological attributes and antioxidant activities of two Iranian pomegranate cultivars under different concentrations of NaCl with or without VCL. Results Salinity negatively affected the growth properties of pomegranate, while foliar spray of VCL-induced salt tolerance by reducing the accumulation of Na+ in the seedlings. Leaf area and shoot and root fresh and dry weight of VCL-treated pomegranate plants showed a significant increase regardless of whether the seedling growth was under non-saline or saline conditions. Chlorophyll loss and reduced photosynthesis efficiency caused by salinity were also ameliorated using VCL. Foliar application of VCL also improved the activity of antioxidant enzymes and caused a reduction in oxidative stress and electrolyte leakage. Conclusions These results suggested that VCL could alleviate the damage caused by salt stress in pomegranate by limiting the agglomeration of Na+ and amending the activities of antioxidant enzymes by which the efficiency of plant increases

Effect of Silicon on Growth and Development of Strawberry under Water Deficit Conditions

Water stress is a major factor that limits agricultural crop production. Silicon (Si) is generally considered as a beneficial element for the growth of higher plants, especially for those grown under stressful environment. This study was conducted to examine the effects of Si on growth and development of strawberry (Fragaria × ananassa ‘Camarosa’) under water stress conditions. A factorial experiment, in a completely randomized design, was used to investigate the effects of three irrigation levels and four Si treatments consisting of 0, 5, 10, and 15 mmol·L−1 potassium silicate (K2SiO3). The results showed that an increase in the levels of water stress caused a decrease in most of the quantitative characteristics such as specific leaf area, chlorophyll fluorescence, net photosynthesis rate, and stomata conductance; addition of Si significantly increased most of the mentioned factors; water stress increased electrolyte leakage, proline, and water use efficiency (WUE); Si treatment significantly decreased transpiration rate and improved chlorophyll content and WUE. Water stress stimulated mineral nutrient absorption whereas Si application decreased it under water stress. In conclusion, it was found that in most of the investigated factors, 10 mmol·L−1 potassium silicate had the best effect on growth and development of strawberry. Besides, Si application had beneficial effects on strawberry plants and the addition of it could alleviate water stress. Keywords: Fragaria × ananassa, potassium silicate, water stress, photosynthesis, mineral nutrien