Algae extract overcoming the adverse effects of saline stress in hydroponic grown tomato plants

摘要

Salt stress is one of the major problems of agriculture, particularly in arid and semiarid regions, limiting plant growth and productivity. Algae extracts have been reported to assist plants in many ways by enhancing crop yield, improving root structures, developing flowering and leaf and fruit set, and enhancing ability to tolerate plant stress. During two sequenced seasons (2015 and 2016) tomato plants were grown under different salinity levels to study whether the algal extract overcomes the adverse effect of salinity on growth performance of tomato plants. Growth was employed within in situ made deep flow technique unit (DFT). Salinity levels were 2000, 4000 and 6000 ppm of sea salt compared with control grown cultures. The applied concentrations of algal extract were 0.0, 1.0, 2.0 and 4.0 g l-1. The growth parameters (leaf number, plant height, leaf area and dry weight of leaves, stems and roots per plant), chemical composition and yield were assessed. Algal extract markedly enhanced morphological criteria of tomato plants to be able to overcome the extremely adverse effect of high salinity level in concern leaf number and plant height, while a slight decrease in leaf area was observed. Plant dry weights, total yield and chlorophyll contentin the plants treated with 4 g l-1 alga extract were superior to the other treatments under the same salinity level. TSS was promoted with increasing alga extract and saline levels. Alga extract reduced the negative effect of Na accumulation in leaves under hyper saline conditions.