Improving Tolerability of Taxodium Distichum Seedlings to Water Salinity and Irrigation Water Deficiency I. Effect of Salicylic Acid on Water Stress

Abstract

This study was carried out at the nursery of Horticulture Research Institute, Giza, Egypt in the two seasons, 2016 and 2017, aiming to investigate the effect of salicylic acid at different level (0, 0.5, and 1.0 g/l) with different levels of field capacity (25,50,75 and 100%) on growth and chemical constituents of Taxodium distichum and also to reduce the amount of water needed for irrigation. Main results of this study could be summarized as follows: The highest value was achieved by the following treatments: salicylic acid at 0 g/l with100% of field capacity level (concerning root fresh and dry weights); salicylic acid at 0.5 g/l with 75% of field capacity level (for plant height, branch number, shoot dry weight, root fresh and dry weights); salicylic acid at 0.5 g/l with 100% of field capacity level (regarding plant height, branch number and root length); salicylic acid at1.0 g/l with 75% of field capacity level (for plant height, root length and root fresh weight); and salicylic acid at 1.0 g/l with 100% of field capacity level (for shoot fresh weight, total carbohydrate and total chlorophyll). The lowest value was obtained by the following treatments: salicylic acid 0 g/l with 25% of field capacity level (for plant height, branch number, shoot fresh and dry weights, root fresh weight, total carbohydrate and total chlorophyll); salicylic acid at 0 g/l with 50% of field capacity level (for plant height and shoot dry weight); salicylic acid at 0.5 g/l with 25% of field capacity level and salicylic acid at 0.5 g/l with 50% of field capacity level (for root fresh weight); salicylic acid at 0.5 g/l with 100% of field capacity level (for root dry weight); salicylic acid at 1.0 g/l with 25% of field capacity level (for root length and shoot dry weight); and salicylic acid at 1.0 g/l with 50% of field capacity level (for shoot dry weight). It is recommended to treat plants with salicylic acid at 0.5 g/l and to apply irrigation at 75% of field capacity level capacity to obtain the highest values of plant height, branch number, shoot dry weight, root fresh and dry weights. This will also save as much water as 25% of field capacity level.

The Role of Salicylic Acid in Reducing Water Requirements for Hibiscus Rosa-Sinensis L. Plant

“…The previous gains may be reasonable because water shortage (drought) usually declines relative water content (RWC) in plants, photosynthetic pigments, net photosynthetic rate and transpiration rate, while it increases the levels of proline, malondialdehyde (MDA), hydrogen peroxide (H2O2), O2 -and electrolyte leakage. On the contrary, applying SA and increasing water In this connection, Saadawy et al (2019) advised to treat Taxodium distichum seedlings with 1 g/l SA + 100% of F.C. to obtain the highest concentrations of total chlorophyll and total carbohydrates.…”