Showing 4 results for Mahmoudi
N Najafi, Sh Mahmoudi, A Reyhanitabar,
Volume 5, Issue 4 (Journal of Science and Technology of Greenhouse Culture 2015)
Abstract
Due to low organic matter content in most of the cultivated soils of Iran and occurrence of drought stress in plants because of low precipitation, application of sewage sludge compost has been recommended for increasing soil organic matter content and improving soil fertility, increasing crop tolerance to water deficit and improving crop yield. So, in this study, the effects of soil moisture and sewage sludge compost levels were investigated on leaf chlorophyll index and some growth traits of alfalfa (Medicago sativa L.) in greenhouse conditions. A factorial experiment, based on randomized complete blocks design with three replications, was conducted with two factors of soil moisture conditions at three levels (0.81FC-FC, 0.56FC-0.75FC and 0.35FC-0.50FC) and sewage sludge compost at four levels (0, 15, 30 and 60 g/kg of soil). Results showed that the effect of soil moisture levels on leaf chlorophyll index was dependent on the level of sewage sludge compost. Soil water deficit significantly decreased shoot and root dry weights and plant height (P<0.01). The sensitivity of alfalfa shoot to soil water deficit stress was greater than its root. Application of 15 and 30 g sewage sludge compost per kg of soil significantly increased leaf chlorophyll index, shoot and root dry weights, plant height and shoot to root dry weight ratio (P<0.01). The interaction effects of soil moisture and sewage sludge compost on leaf chlorophyll index, shoot and root dry weights, plant height and shoot to root dry weight ratio were significant (P<0.01). The highest shoot and root dry weights, plant height and shoot to root dry weight ratio were observed at 30 g sewage sludge compost per kg of soil and 0.81FC-FC soil moisture level. Also, the results showed that application of 30 g sewage sludge compost per kg of soil alleviated water deficit-induced adverse effects on alfalfa plant.
M.h Ghafarian Mogharab, M Mahmoudi, M.j Malakouti,
Volume 5, Issue 4 (Journal of Science and Technology of Greenhouse Culture 2015)
Abstract
To date, limited research has been done worldwide on uptake and translocation of nanoparticles (NPs) by plants. To evaluate such processes, soybean (Glycine max L.) was cultured in modified Hoagland nutrient solution containing Fe3O4 NPs with concentration of 60 mg/L, and 33 mg/L iron chelate (Fe-EDTA) was taken as control. After 28 days, the strength of magnetic signal was measured in different organs of the soybean by vibrating sample magnetometer (VSM) instrument. Result showed no magnetization signal from the control plants, but signals with various strengths were found in the tissue samples of the treated plants. Strong magnetic signal in soybean leaves clearly indicated the uptake and translocation of Fe3O4 NPs by roots and xylem. The strongest magnetic signal (138 memu/g) was detected in roots, and transfer coefficient of NPs from roots to leaves was about 0.9 percent. Exudates and surface charge of roots caused accumulation of magnetite NPs on soybean roots' surface. A small fraction of particles moved through simplastic pathways into the xylem and streamed to leaves via sap flow. NPs were accumulated in the crown more than other aerial parts, due to vascular change in structure (root to shoot). In summary, results demonstrated that Fe3O4 NPs can be taken up by soybean and be translocated to other plant tissues in molecular form
Sh. Mahmoudi, N. Najafi, A. Reyhanitabar,
Volume 6, Issue 2 (Journal of Science and Technology of Greenhouse Culture 2015)
Abstract
Improvement of plant nutrition is one of the approaches for augmenting the drought stress tolerance in plants. Due to low organic-matter content in most soils in arid and semi-arid regions of Iran, application of organic-wastes’ compost can increase water-holding capacity of the soil and improve plant nutrition. So, in this study, the interactive effects of soil moisture and municipal sewage-sludge compost were investigated on some soil chemical properties and concentration of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) in alfalfa (Medicago sativa cv. Garehyounjeh) forage in greenhouse conditions. A factorial experiment, based on randomized complete blocks design with three replications, was conducted with two factors of soil moisture at three levels (0.81FC-FC, 0.56FC-0.75FC and 0.35FC-0.50FC) and sewage sludge compost at four levels (0, 15, 30 and 60 g/kg of soil). The results showed that the main and interactive effects of sewage sludge compost and soil moisture on the concentration of N, P, K, Ca and Mg in alfalfa forage and electrical conductivity (EC), pH and K concentration in soil solution were significant. As soil moisture content decreased, the concentration of N, K, Ca and Mg in alfalfa forage and the EC and K concentration of soil solution significantly increased while the concentration of P in alfalfa forage and pH of soil solution were significantly decreased. In all the studied soil water contents in this experiment, application of 60 g sewage-sludge compost per kg of soil as compared to the 30 g/kg level, significantly decreased alfalfa growth by increasing the salinity of soil solution. Under well-watered and water-deficit stress conditions, application of 30 g sewage-sludge compost per kg of soil improved alfalfa nutrition and its forage quality.
S. Mahmoudi, A. Mohammadkhani, V. Rouhi,
Volume 7, Issue 2 (Journal of Science and Technology of Greenhouse Culture 2016)
Abstract
Aloe vera is one of the medicinal plants, resistant to drought and high temperatures, that its gel has many applications in pharmaceutical, health and food industry. This experiment was conducted to determine the effects of salinity stress, caused by sodium chloride (NaCl) and calcium chloride (CaCl2), on leaf weight, gel content and ratio of some nutrients in Aloe vera, in Research Greenhouse of Shahrekord University, in 2012. This experiment was based on a randomized complete blocks design with 16 treatments and three replications. Treatments included four levels of NaCl concentration (0 (control), 30, 60 and 90 mM), three levels of CaCl2 (5, 10, 20 mM) and combinations of the two salts Based on the results, effect of salinity on wet and dry weight of leaf and gel, percentage of sodium, calcium, magnesium, potassium, and K/Na and Ca/Na ratio was significant. Increasing the concentration of NaCL, CaCl2 or their combination, reduced the percentage of magnesium, calcium, potassium, wet and dry weight of gel content and leaf yield. Results of this study showed that Aloe vera is not much tolerant to salt stress and its cultivation is not recommended in soils with EC value of more than 7 dS/m. Overall, under similar EC, the toxicity of NaCl is more than CaCl2 and attention to potassium and calcium nutrition is important under salinity stress.
