Open Access Case study

Investigating the Effects of Atmospheric Gaseous Pollutants on the Vegetation of Nezahat Gökyiğit Botanical Garden in Istanbul, Turkey: A Case Study and Survey

Esra Deniz Deniz Güner, Rukiye Tıpırdamaz, Gülen Güllü

International Journal of Plant & Soil Science, Page 1-13
DOI: 10.9734/IJPSS/2017/29660

We assessed the effects of gaseous air pollutants on the vegetation of the Nezahat Gökyiğit Botanic Garden in Istanbul, Turkey, based on the physiological responses of common specie Fraxinus angustifolia as it is the most common type of tree located all around the Garden. In order to assess the level of air quality, sulfur dioxide (SO2), nitrogen dioxide (NO2) and ozone (O3) concentrations were measured. The results clearly show that the region, in general, has been identified as under the significant impact of NO2. The leaf samples of Fraxinus angustifolia were collected during the period of plant growth months (May, June, August, September), and heavy metal content, water content and photosynthetic pigment analysis were performed in leaves tissues, such as chlorophyll a, chlorophyll b, total chlorophyll, carotenoid amount (µg g-1). Heavy metals accumulation on the leaves were observed at the locations close to the main roads.

Average total chlorophyll content observed in generally 87 ± 10 mg g-1 fresh weight (mean ± SD) level. A statistically significant relationship between NO2 level and photosynthetic activity, total chlorophyll content and carotenoid has been identified. As the NO2 level increases, increase of photosynthetic activity, chlorophyll a and b and total chlorophyll content and decrease of carotenoid levels were observed. Although the level of air pollution variations over the sampling points have been determined during the growth phase of the plant, Fraxinus angustifolia plant species located all around the garden showed resistance to air pollution.

Open Access Original Research Article

Response of Common Bean (Pharsalus vulgaris L.) Cultivars to Combined Application of Rhizobium and NP Fertilizer at Melkassa, Central Ethiopia

A. Habtamu Assefa, Berhanu Amsalu, Tamado Tana

International Journal of Plant & Soil Science, Page 1-10
DOI: 10.9734/IJPSS/2017/30864

Soil fertility is one of the factors limiting the production of common bean in Ethiopia. Thus, field experiment was conducted to assess the effect of Rhizobium and NP fertilizers combination on nodulation, growth, yield components and yield of common bean cultivars and economically beneficial combination of NP and inoculants for each cultivar. The experiment was conducted at Melkassa Agricultural Research Center under rain fed conditions during the main cropping season. The experiment plot was laid at split plot design in three replications. Seven common bean cultivars (sub-plot factor) with five levels of NP fertilizer combined with inoculant (main-plot factor) (full recommended rate of NP fertilizer or 46 kg ha-1 of P2O5 and 41 kg ha-1of N alone, Rhizobium with 23 kg ha-1 of P2O5 and 20.5 kg ha-1of N, Rhizobium with 11.5 kg ha-1 of P2O5 and 10.25 kg ha-1of N, Rhizobium alone, and control) used as treatments. The main effects of combination of NP with inoculant significantly influenced, nodule number, nodule color, plant height and number of primary branches. All inoculated treatments recorded highest nodulation parameters over uninoculated. The combination of 23 kg ha-1 of P2O5 and 20.5 kg ha-1 of N with inoculant recorded highest nodule number (17.14) per plant. Among the cultivars, Nassir was best for nodulation parameters. The interaction of combined application of NP fertilizer with inoculant and cultivars had significant effect pods per plant, 100 seed weight and grain yield. Analysis of variance for net benefits significantly affected due to common bean cultivars, combine application of NP fertilizer with inoculant and interaction of cultivars and combined application of NP fertilizer. The Economic analysis indicated that full recommended rate of NP fertilizer had economical advantage for only cultivar Awash-1. Among the cultivars Batu, DRK and Nassir recorded the highest marginal rate of return due to inoculation relative to other tested combination. Finally, Study conclude that, rhizobium strain (EAL 429) is more effective than that of indigenous soil Rhizobium population. Cultivar Nassir seemed to be more responsive to infection by inoculated strain EAL 429. However, the results presented here need to be further evaluated for sound recommendation.f

Open Access Original Research Article

The Influence of Selected Soil Physicochemical Properties on Radionuclide Transfer in Cassava Crops

Chijioke M. Amakom, Chikwendu E. Orji, Benedict C. Eke, Benedict C. C. Eke, Uchenna A. Okoli, Chidiebere S. Ndudi

International Journal of Plant & Soil Science, Page 1-7
DOI: 10.9734/IJPSS/2017/30913

Radionuclide contamination through the food chain is a major pathway for radiotoxicity to man. The radionuclides of natural origin are absorbed from the soil just like every other nutrient the plants needs for their survival. A study on the effects of some soil physicochemical parameters on the radionuclide transfer factors from soil to plant was carried out. The soil physicochemical properties obtained from the study suggest that the soil in this study fell within the sand category with a pH range of 5.06 – 6.08. Radionuclide activity concentrations for the soil samples ranged from 9.73±0.92 – 56.38±3.29, 35.91±1.71 – 147.26±4.06 and 137.09±4.20 – 247.33±3.42 Bq/Kg for the radionuclides 226Ra, 232Th and 40K respectively. For the cassava samples, the activity concentrations ranged from 19.28±5.29 – 89.22±5.09, 70.46±1.59 – 203.48±1.56 and 39.34±5.59 – 442.45±6.99 for 226Ra, 232Th and 40K respectively. From the correlation statistics, the soil pH and silt content made the most significant contribution in the radionuclide transfer factors.

Open Access Original Research Article

Factors Affecting Solubilization of Rock Phosphates in Soils

A. M. Elgala, A. Amberger

International Journal of Plant & Soil Science, Page 1-8
DOI: 10.9734/IJPSS/2017/28526

The aim of this work was to conduct laboratory and pot experiments to study the ability of plant roots on solubilizing various sources of rock phosphate and factors that may facilitate or inhibit their activity. The effect of adding organic matter or sulphur in solubilizing rock phosphate added to alkaline and calcareous soil was studied. A split medium – split root technique experiment was conducted to study also the effect of N form, soil type, source and nature of rock phosphate on the pH, P solubility in the medium and P uptake by bean plants (Vicia faba var. balady). Results show that the highest NaHCO3 extractable P of incubation experiment were found for both soils treated with superphosphate. The behavior of rock phosphates in the two soils indicated slight solubilization in the alluvial soil and no remarkable change of extractable P in the calcareous soil as compared to the control. Regarding the effect of N form and P on growth and root exudates of bean plants, results indicated that the highest recorded total dry weight was found when both N forms were applied in the ratio of 1:4  or   alone. Results of root exudate analyses for amino acid content indicated the presence of several amino acids and variations in the amount were only with lysine. The highest content (115 μδ/100 ml) was in the root exudate of the complete nutrient solution (Hoagland solution) and the lowest value (24 μδ/100 ml) in the exudates of bean plants fed with as the only N form. The rock phosphate from Abou zaabal gave the highest P content in acid soil in the presence of plant. The highest drop in pH value in the collected solutions was when NH4+ alone was the N source.

Open Access Original Research Article

Effect of Aluminum Toxicity on Root Growth and Morphology of Common Bean (Phaseolus vulgaris L.) Genotypes

Hirpa Legesse, R. Nigussie-Dechassa, Setegn Gebeyehu, Geremew Bultosa, Firew Mekbib

International Journal of Plant & Soil Science, Page 1-13
DOI: 10.9734/IJPSS/2017/26045

Aims: To investigate the effect of aluminium on root growth, morphology and the concentration of aluminium in the root tissues of two common bean genotypes(new BILFA 58 and Roba 1) varying in soil acidity tolerance.

Study Design: Factorial combinations of five rates of aluminum (0.0, 12.5, 25.0, 50.0, and 100.0 mg Al kg-1 soil) and two genotypes were laid out in a completely randomized design of three replications.

Place and Duration of Study: The experiment was conducted in the vegetation hall of Nekemte Soil Laboratory, western Ethiopia from July to October, 2012.

Methodology: For each treatment, four plants were raised per pot, data related to  root growth and aluminum content of the crop were collected at 25 and 35 days after seedling emergence (DAE).

Results: Aluminium and genotype interacted significantly (P=0.01) to affect root growth parameters and aluminium contents of the roots. A difference in inhibition of tap root elongation was observed between the two genotypes at different levels of aluminum. As the applied aluminum level increased, the tap root length of both genotypes decreased under both lime-treated and -untreated soils. On average, application of aluminium led to 14.8, 9.9, 14.6 and 37.3, 22.3 and 16.2%, reduction in root biomass, total root length per volume soil, and root surface area at 25 and 35 DAE, respectively. In contrast lime application resulted in reduction of aluminium content of the roots by 56.3%.

Conclusion: Common bean production on strongly acidic soils with higher contents of exchangeable aluminium could be sustained through the integrated use of tolerant genotypes and application of modest rates of lime.

Open Access Original Research Article

Effects of Seed Treatment on Removal of Physical Dormancy in Canna indica L.

K. Okonwu, C. A. Ariaga

International Journal of Plant & Soil Science, Page 1-9
DOI: 10.9734/IJPSS/2017/31048

The effects of different seed treatments on the germination of Canna indica L. were investigated. The seeds were subjected to chemical (sodium nitrate, sulphuric acid and hydrochloric acid), physical (hot water) and mechanical (puncturing the seed coat) scarification and allowed to germinate given a period of 16 days. The seeds were treated as follows: immersion in 50%, 70% and 100% sulphuric acid (H2SO4) and hydrochloric acid (HCl) for 20, 40, 60, 80, 100 and 120 minutes respectively, 24 hours soaking in 10 mM, 50 mM, 100 mM, 1000 mM Sodium nitrate (NaNO3) and soaking in hot distilled water (70°C and 100°C) for 5 and 10 minutes respectively. Mechanical scarification, chemical scarification using 70% HCl and concentrated sulphuric acid and hot water treatment (70°C) had considerable effect in promoting germination with maximum germination percentage of 50%, 35%, 88%, and 36% respectively. Canna indica seeds treated with NaNO3 had the least germination (28%). However, treatment with concentrated sulphuric acid was most efficient in promoting germination (88%). Statistical analysis carried out indicated that there was significant difference at P=0.05 in the germination of seeds treated with hot water, mechanical scarification, sulphuric acid and hydrochloric acid at 70% and 100% but there was no significant difference in the germination of seeds treated with 50% of both hydrochloric acid and sulphuric acid respectively.