ECOPERSIA
Volume:9 Issue: 1, Winter 2021

Germination is one of the important stages of plant lifecycles that may be affected by different natural stress such as allelopathic. This study was performed to investigate the effects of priming with gibberellic and salicylic acid on germination improvement and resistance of Hibiscus sabdariffa under stress with allelopathic compounds of Eucalyptus camaldulensis.

The experiment was conducted as a factorial experiment in a completely randomized design with four replications in laboratory conditions. The first factor consists of pre-treatment of seeds with gibberellic acid (125, 250, and 500mg/kg) and salicylic acid (100, 200, and 300mg/l), and the second factor was five concentrations (0, 25, 50, 75, and 100mg /l) of allelopathic compounds of eucalyptus. Studied characteristics have consisted of germination percent, germination speed, root length, shoot length, seedling length, and vigor index.

Results showed that Eucalyptus allelopathic extract has an inhibitory effect on seed germination of H. sabdariffa. When the extract concentration increased, the germination and seedling growth decreased significantly. In contrast, seed priming with gibberellic and salicylic acid increased the measured characteristics at all levels compared to non-primed seeds. A comparison of means showed that seed priming with gibberellic acid 250mg/kg increased germination 25% compared to an unprimed seed.

The response of this species to seed pre-treatment with gibberellic acid has the most effect. The seed pre-treatment technique with the mentioned treatment could increase germination and establish seedling by improving germination percentage and speed under allelopathic stress before planting.

Water quality is an important factor in determining groundwater uses. An effort has been made to determine the groundwater quality of the Yazd-Ardakan aquifer. This research was conducted to fill the research gap in aquifer quality in the study area and make a comprehensive evaluation of the study aquifer using different water quality indices. The results can be used for decision-makers better to understand the water quality situation in the area.

In order to carry out this study, the Ryznar Stability Index (RSI), Langelier saturation index (LSI), Larson–Skold index (LS), and Puckorius scaling index (PSI) were considered to determine groundwater quality for industrial use. Also, the drinking water quality index (WQI) and FAO water quality index (FWQI); and irrigation water quality index (IWQI) were employed to categorize water suitability for drinking and irrigation uses. Finally, the spatial distribution of water quality parameters was assessed.

This study showed that the study aquifer is less corrosive based on PSI, significant, and heavy corrosive, according to LI. Also, results of the aquifer classification based on WQI indicated that about 45% of the aquifer is categorized as poor, very poor, and undesirable for drinking purposes. Finally, IWQI showed that %2.8 of the aquifer is categorized as “non-restriction” class and %4.1 as a “severe restriction” class for irrigation.

Therefore, it could be concluded that Yazd-Ardakan aquifer water quality is exacerbating. Consequently, the water quality and water treatments should be taken into account to mitigate the exacerbating trend of the Yazd-Ardakan aquifer.

The present investigation aimed to study the effect of traditional-coal-mining on the spatial distribution pattern of soil properties in the Lavij-Forest located in the western part of the Hyrcanian area-North Iran.

After selecting a mine area, 16 plots (20×20m) were established by systematic-randomly (60×60m) in an area of 4 ha (200×200m-mine entrance placed at center) which was affected by coal-mining. An area adjacent to the mine (same site conditions) that was not affected by the mining activity considered as the control-area. In order to investigate soil Physio-chemical properties one sample was taken from the 0-10cm depth in each plot. To study the spatial-pattern of soil properties and lead and cadmium concentrations in the mining area, an area of 80×80m (the mine at the center) was considered and 80 soil samples were systematic-randomly taken (10m intervals). Geostatistical analysis was performed via Kriging method and GS+ software.

Results showed that mining had led to a significant decrease in soil moisture, pH, EC, nitrogen, and potassium level. Lead and cadmium concentrations were significantly higher in mine area (Pb: 10.97±0.30, Cd: 184.47±6.26mg.Kg-1) in comparison to control-area (Pb: 9.42±0.17, Cd: 131.71±15.77mg.Kg-1). The range value calculated for variograms of cadmium and lead was 210m. The kriged maps showed that the concentration of cadmium and lead near the mine crater was considerably higher in comparison with adjacent points.

The findings showed that coal mining activity had negative effects on the forest soil and it is necessary to consider reclamation of contaminated soil in these areas.

Food security depends on the sustainable use of natural resources. Recently, local communities have started planting sumac (Rhus coriaria L.) as an agroforestry system in Iranchr('39')s arid and semi-arid regions. The financial benefit of converting sloping lands to the sumac agroforestry system was compared with cropping cereals land-use option based on wheat and barley production. The study site is located in a semi-arid area in the Eastern part of the Arasbaran Biosphere reserve in Hurand county, East Azerbaijan province, Iran.

Data were collected through a combination of socio-economic survey and field inventory. For the household questionnaire survey, 63 samples from four villages were purposively selected. Those who converted low yield croplands to sumac agroforestry system and collected it.

Results showed that sumac collection varied from 144kg in Mollalu to 776kg in Tabestanagh per household annually. Sumac income contributes about 30-40% to total household income, followed by farming and off-farm activities. The net present value of sumac was 4.6 times higher than cropland. The inclusion of sumac income in total household income calculations considerably reduced income inequality among households by 0.36. The processing operations done on the sumac fruit were cleaning, drying, flouring, and packaging. It increased the processing benefit by 10.5USD per kg. The main marketing constraints were selling in raw form without grading and standardization, unawareness about prices, low marketing information, etc.

expanding the sumac agroforestry systems by increasing the abundance and density of fruit-providing species is an important way of improving livelihood and security in rural areas.

The effects of potassium silicate nanoparticles (PSN) and effective microorganisms (EM) were studied on the growth of alfalfa (Medicago sativa L.) and sainfoin (Onobrychis sativa Lam.) and soil.

Split-split plot in a complete randomized block design with three replications was used for this experiment. Planting time in two seasons (autumn and spring) as the main plot, facilitators in five levels, including control, PSN (500 and 1000mg/lit), and EM (1 and 2%), as sub-plots and two legume species as sub-sub plot were studied in the field. In the four-leaf step of plants, PSN and EM were added in three steps as a solution.

The highest amount of plant viability (80, 82.22%), height (59, 68.33cm), basal diameter (13.33, 16.66cm), canopy cover (993.33, 1242.66cm2), leaf area index (67.79, 84.93cm2), relative water content (70.46, 88.32%), chlorophyll (0.87, 0.72mg.g-1), photosynthesis rate (27.29, 28.49µmolco2.cm-2s-1), number of inflorescence (57.33, 56N/m2) and 1000-grain weight (33.30, 3.89g.m-2) were in sainfoin (EM2%) and alfalfa (PSN1000mg/lit), respectively. Total biomass (423.87 and 374.50g.m-2) was maximum in PSN1000mg/lit for both species. EM and PSN caused desirable effects on the soil characters of species substrates (p<0.01). The maximum value of all studied soil characters belonged to PSN1000. Additionally, autumn sowing compared to spring planting enhanced the studied traits of planted species and their substrate soil.            

The usage of appropriate PSN and EM concentration in this study to restore dry-farming lands and improve species growth and forage yield can be suggested.

Studying the effects of nanoparticles on living organisms seems to be necessary, especially in plants as the first trophic level. Thus the phytotoxicity of different concentrations of nano-TiO2 on five desert plant species was investigated in the present study.

The phytotoxicity of different concentrations (0, 10, 100, 500, 1500mgl-1) of nano-TiO2 on five desert plant species of Halothamnus glaucus Botsch, Haloxylon aphyllum L., Nitraria schoberi L., Zygophyllum eurypterum Boiss. & Buhse, Halocnemum strobilaceum were investigated using seed germination percentage, radicle, and plumule elongation measurement. Experiments were conducted based on a completely randomized design with four replications.

Outcomes of the study demonstrated that the application of nano-TiO2 had no adverse effect on germination at low concentrations (up to 500mgl-1), it also increased the germination of H. aphyllum (72 to 88%). The concentration of 1500mgl-1 had a negative effect on germination and radicle growth of three species of N. schoberi (decrease in germination from 32 to 20% and radicle length from 13.85 to 10.68cm), H. aphyllum (decrease in germination from 72 to 44% and radicle length from 6.105 to 4.03cm).

Generally, in most plants, low concentrations of nano-Tio2 did not significantly affect germination and seedling growth, but in high concentrations (1500mgl-1) due to toxicity effect, germination and seedling growth were reduced. Therefore, in using nanoparticles, attention to dosage, which is useful and not causes toxicity, is significant.

Biochar is a soil amendment used to improve soil quality and plant productivity in an agricultural application, and there were fewer researches to use it in rangeland species. This study aimed to determine if lignite and wheat straw biochar (WSB) could be used to promote Astragalus podolobus growth, inclusive Plant height, crown diameter, canopy cover, the volume of cover, leaf area, and leaf perimeter. In this study, it is assumed that WSB and lignite’s use will increase the growth of A. podolobus species. A. podolobus, as a palatable shrub from the Leguminosae family, is a native species of Turkmen Sahra.

A greenhouse experiment was designed with (WSB) and lignite, at 1.25%, 2.5%, and 3.75%w/w of soil in six replications. The soil texture was clay loam. Statistical analyses were performed by two-way analysis of variance using the SPSS16 statistical software.

  In lignite application, the highest height, crown diameter, canopy cover, and volume of cover were observed for a 3.75% application rate after the 4th month and were 25.03cm, 23.52cm, 528.65cm2, and 15581cm3, respectively. While the highest values of these parameters for WSB were obtained for 2.5% of the application rate after the fourth month and were 22.62cm, 20.66cm, 401.66cm2, and 11318.3cm3, respectively.

Plant height, crown diameter, canopy cover, the volume of cover, leaf area, and leaf perimeter were promoted by increasing lignite dosage (3.75%) in the soil while nearly all parameters decreased at the same WSB incorporation dose.