Nooshin Derakhshan; Hossein Alaei; Rohollah Saberi Riseh; Ebrahim Sedaghati; Asghar Rahimi
Abstract
Salinity can prevent the uptake of soil mineral ions due to the negative effect of sodium ions and disturbance of ion balance, but the use of Trichoderma biocompounds improves growth under salinity stress. To investigate the effect of four salinity-resistant Trichoderma strains on growth traits and mineral ...
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Salinity can prevent the uptake of soil mineral ions due to the negative effect of sodium ions and disturbance of ion balance, but the use of Trichoderma biocompounds improves growth under salinity stress. To investigate the effect of four salinity-resistant Trichoderma strains on growth traits and mineral element uptake of eggplant seedlings under stress conditions, an experiment has been performed in a completely randomized factorial design with three replications in the greenhouse of Vali-e-Asr University of Rafsanjan during 2016-2017. The first factor is salinity in four levels including the control and concentrations of 8, 12, and 16 dS/m and the second factor is Trichoderma as T. aureoviride (T148-2, T189-4) and T. virens (T145, T133-1) as well as the control. The results show that under the influence of salinity, a significant decrease in growth traits takes place. At the highest salinity level, the average dry weight of roots and shoots is 50% and 72%, respectively. For stem diameter and seedling height, a 20% decrease is observed compared to the control. However, inoculation with Trichoderma improves these traits, resulting in a 1.6-fold increase in root dry weight (T142-8), a 2.7-fold increase in shoot dry weight (T133-1), and a 1.3-fold increase in seedling height (T189-4) in comparison to the control. The highest diameter increase could be observed in T142-8 strain by 38%. Using Trichoderma leads to significant changes in sugar, sodium, potassium, and calcium content. The results of this study show that Trichoderma can be a suitable biological agent to increase tolerance at high levels of salinity stress and improve the growth traits of eggplant seedlings.
Asghar Rahimi; Mohammad Reza Jahansooz; Hamid Rahimian mashhadi; Majid Pouryousef; Shahab Maddah Hosseini
Volume 11, Issue 2 , November 2009, , Pages 49-63
Abstract
Photosynthesis, stomatal conductance and leaf water potential characteristics were examined in two plantago species (Plantago ovata Forssk and P. psyllium L.), with gradually improving water stress for several days and permitting to recover by re-watering (withholding for 2, 4, 6, 8 and 10 days) in Melbourne ...
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Photosynthesis, stomatal conductance and leaf water potential characteristics were examined in two plantago species (Plantago ovata Forssk and P. psyllium L.), with gradually improving water stress for several days and permitting to recover by re-watering (withholding for 2, 4, 6, 8 and 10 days) in Melbourne University in 2006. Factorial experiments based on completely randomized design with four replications were used. The photosynthetic rate and stomatal conductance decreased rapidly by withholding water. After re-watering the recovery rate of photosynthesis and stomatal conductance decreased gradually, as the days became longer. The different rates of recovery of photosynthesis and stomatal conductance followed by drought stress. However, the potentional of photosynthesis recovery was more than stomatal conductance. It is also concluded that French psyllium had higher mesophyl and stomatal conductance recovery when compared to Isabgul, although recovery of photosynthesis in Isabgul was higher than French psyllium. The results showed a clear and close correlation between leaf water potential and recovery level of photosynthesis rate and stomatal conductance. A close correlation was also observed between photosynthesis and leaf water potential, stomatal conductance and relative water content.