Mohammad Sadat Farizani; Hamid Reza Khazaee; Ali Gazanchian
Abstract
Introduction: Beautification of urban space and creating attractive face for cities by development of green space has caused to capita of urban green space be introduced as an important factor in urban development. Meanwhile, the important role of cover plants, especially turf grass, in creating green ...
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Introduction: Beautification of urban space and creating attractive face for cities by development of green space has caused to capita of urban green space be introduced as an important factor in urban development. Meanwhile, the important role of cover plants, especially turf grass, in creating green spaces has caused to add quickly the area of these beautiful plants in the cities. Nevertheless, existence of plants with high water requirements between the turf grasses, have created limitations in terms of water requirements supply. The grass planted in the country is mainly from imported seed types that are not so compatible with dry and semi-arid conditions in our country and from this point of view, sometimes they create limitations in terms of water supply. One of the native grasses in the country, is Tall Fescue (Festuca arundinaceous), which is a variety of cool-season, perennial and herbaceous grasses. One of the strategies to preserve grass under drought stress is improving soil structure with the aim of increasing the moisture. Organic compounds that improve soil physical and biological conditions (such as municipal waste compost and manure) can be effective. Using compost improves soil structure and strengthens soil mineral content and allows soil to retain moisture for longer. Because compost can hold water about two to six times its volume and prevent it from being wasted. Compost in heavy soils, improves soil porosity and makes the soil better ventilation elderly. In light soils, it acts like a sponge and by keeping water and food safe, it will greatly prevent them from being washed. Therefore, present research was done to evaluate the effect of mixing different amounts of Municipal Solid Waste (MSW) compost with soil on some physiological properties of Tall Fescue native grass under moisture stress conditions.
Materials and Methods: This research was conducted in the form of two experiments in research greenhouse of Ferdowsi University of Mashhad. The first experiment with aim of evaluating percentage and rate of grass emergence was conducted in a completely randomized design with four replications that the experimental treatments consisted of ten different levels of compost mixing with soil (10 up to 100 t.ha-1) and control treatment (agronomic soil without mixing compost). In the second experiment, three values of 70, 80 and 90 tons of compost per hectare plus control (no compost consumption) as the first factor and three levels of moisture stress of 25, 50 and 100 percent of field capacity as intense stress, mild stress and without stress, respectively as the second factor that were compared in factorial by a completely randomized design with four replications.
Results and Discussion: The results of the first experiment showed that the amounts of 70, 80 and 90 tons per hectare increased significantly the percentage and rate of grass emergence due to increased fertility and higher water holding capacity and in these treatments, the positive effect of rising water holding capacity has been dominated on negative effect of electrical conductivity of the soil and this topic has led to an improvement in the percentage of grass emergence in these treatments. Furthermore, in the amounts of 70, 80 and 90 tons of compost per hectare, the bulk density of soil significantly decreased and the C/N ratio dramatically increased. In the second experiment, with increasing drought stress in different amounts of compost, the total chlorophyll content decreased and relative water content of plant, proline and electrolyte leakage increased. In the compost treatment of 90 tons per hectare, due to its high ability to store water, the cell membrane integrity was more preserved and it was done less understanding of stress. The shoot dry weight decreased significantly as a result of increasing the severity of drought stress.
Conclusion: Based on the findings of this study, application of 90 tons of compost per hectare significantly improved some of physiological traits for Tall Fescue grass in drought stress conditions. Also, it seems that Tall Fescue grass cleverly has tried to deal with drought stress with target of increase the amount of moisture available for itself. Therefore, using 90 tons of compost per hectare for Tall Fescue grass in low water conditions and occurrence of moisture stresses is recommended.
Mohammad Hossein Sheikh Mohammadi; Nematollah Etemadi; Ali Nikbakht; Mostafa Arab; Mohammad Mehdi Majidi
Abstract
Introduction: Drought and salinity are the most detrimental abiotic stresses for turfgrass growth across a wide range of geographic locations. Most cool season grass species are not well adapted to extended periods of drought and salinity stress. The decline in turf quality caused by drought and salinity ...
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Introduction: Drought and salinity are the most detrimental abiotic stresses for turfgrass growth across a wide range of geographic locations. Most cool season grass species are not well adapted to extended periods of drought and salinity stress. The decline in turf quality caused by drought and salinity stresses is a major concern in turfgrass cultivation and management. Therefore, developing management practices for improving drought and salinity resistance of turfgrasses has become imperative in arid and semiarid regions. Grass genotypes differ in their responses to drought and salinity stresses, which involve changes in morphological and physiological aspects. Understanding of relative involvement of each morphological and physiological characteristic in drought and salinity tolerance is important in selecting grass genotypes to facilitate breeding of drought and salinity-tolerant genotypes. The purposes of this research were to make selections of genotypes tolerant to drought and salinity stress for turfgrass management program.
Materials and Methods: To study some morphological and physiological responses of six Iranian crested wheatgrasses (Agropyron cristatum L.) under drought and salinity, an experiment was conducted in the greenhouse of College of Abureyhan, University of Tehran, Iran. Six Iranian Agropyron cristatum genotypes were collected from six locations in Iran. Agropyron cristatum genotypes were planted in polyvinyl chloride tubes and kept in the greenhouse. Pots were filled with sandy loam soil which had been sterilized in an oven at 160ºC for 6 h. Irrigation was applied as needed to prevent any visible stress during grass establishment. Grasses were watered three times weekly to maintain plants under well-watered conditions and soil moisture at field capacity. The experiment consisted of three treatments: 1) well-watered plants were irrigated three times per week with distilled water (control), 2) Drought stress was imposed by withholding irrigation for 45 days (drought stress), and 3) plants were irrigated daily with 100 mL of 9 dS.m–1 NaCl solution (salinity stress). To avoid primary salinity shock, the soil in each pot was drenched with 100 mL NaCl solution at incremental electrical conductivity (EC) by 3 dS.m–1 per day until the final EC reached 9 dS.m–1. Data were subjected to analysis based on a split-plot design with water treatments as main-plots and genotypes as sub-plots. Irrigation treatment as the main factor in three levels (control, drought, and salinity) and crested wheatgrass at six levels were considered as sub-plots. Studied characteristics such as height, turf quality, chlorophyll content, soluble carbohydrates, relative water content, electrolyte leakage, root penetration, and effective root depth were recorded. Statistical significance was tested using the analysis of variance procedure in SAS 9.1 (SAS Institute Inc., Cary, NC). Differences between the means were determined using the Fisher’s protected LSD test at the 5% probability level.
Results and Discussion: The results of this study showed that drought and salinity stress decreased the quality of crested wheatgrass masses, and reduced the level of quality varied among the masses. Throughout the experiment, ‘Sabzevar’ and ‘Damavand’ under drought conditions and ‘Sabzevar’, ‘Arak’ and ‘Damavand’ under salinity conditions maintained higher Turf quality compared with other genotypes. Total chlorophyll content of ‘Sabzevar’ and ‘Damavand’ were higher than other genotypes under drought and salinity conditions. The maintenance of higher chlorophyll content has been associated with better drought and salinity tolerance in plant. The soluble sugar content of ‘Sabzevar’ and ‘Damavand’ under drought conditions and ‘Sabzevar’, ‘Arak’ and ‘Damavand’ under salinity conditions were higher than other genotypes during the experiment. Soluble sugar content is an important compatible osmolyte in plants. Increased accumulation of soluble sugar content in stressed plants may be an adaptation process and resistance strategy to abiotic stresses in plants. Throughout the experiment, ‘AEKQI’, ‘Sabzevar’ and ‘Damavand’ genotypes under drought conditions and ‘Sabzevar’ genotypes under salinity conditions maintained higher relative water content in compared with other genotypes. Higher RWC indicates the ability of the leaf to maintain its higher water content under stress conditions with the simultaneous capability of the root system to take up adequate water. Based on morphological and physiological analysis for drought and salinity tolerance in investigated genotypes, the tolerance ranking would appear to be ‘Sabzevar’ > ‘Damavand’ > ‘Arak’ > ‘Urmia’ = Takestan > ‘Hashtgerd’ under drought stress and ‘Sabzevar’> ‘Arak’ > ‘Damavand’ > ‘Takestan’ = ‘Hashtgerd’> ‘Urmia’ under salinity stress. The results of this study showed that ‘Sabzevar’ and ‘Damavand’ genotypes had good tolerance to drought stress, and ‘Sabzevar’ and ‘Arak’ genotypes had good tolerance to salt stress than other Iranian crested wheatgrass genotypes.
Soheila Javahery; Hossein Zarei; Seyyed Ali Reza Movahedi Naeini; Ghorbanali Roshani
Abstract
In current study, seven organic fertilizers including; Leaf Mold (LM), Rice Husk (RH), Manure, Spent Mushroom Compost (SMC), mixture of LM, RH and SMC (M 1), mixture of LM, RH and Manure (M 2) with the ratio of 1:1:1 and control (no fertilizer) along with some levels of soil compactness comprising roller ...
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In current study, seven organic fertilizers including; Leaf Mold (LM), Rice Husk (RH), Manure, Spent Mushroom Compost (SMC), mixture of LM, RH and SMC (M 1), mixture of LM, RH and Manure (M 2) with the ratio of 1:1:1 and control (no fertilizer) along with some levels of soil compactness comprising roller weights of 36, 56, 76 kilogram were used. Treatments were applied in a strip plot design with three replications, in research farm of Gorgan University of Agricultural Sciences and Natural Resources during fall 2008-2009. Effects of these treatments were investigated on chlorophyll content of lawn, amount of density and cover rate, growth height and percent of plant dry matter in fall season. According to results, SMC and RH treatments in first compactness, manure and M2 treatments in second compactness and manure treatment in third compactness showed the maximum chlorophyll content. The most and the least amount of nitrogen in each three compactness levels were observed in manure and control treatments, respectively. The highest density was related to manure treatment and the lowest one was related to LM treatment. In each three compactness, maximum and minimum height was observed in manure and control treatments, respectively. This project results will be used for lawn management in relation to the use of organic fertilizer and compactness rate of planting bed in Gorgan city conditions.