Toxicity of Diesel Fuel Towards Plant Seeds as Reflected by Seed Germination Outcomes, Sprout Length and Fresh Weight

Transcription

1 American-Eurasian J. Agric. & Environ. Sci., 8 (): 67-7, 00 ISSN IDOSI Publications, 00 Toxicity of Diesel Fuel Towards Plant Seeds as Reflected by Seed Germination Outcomes, Sprout Length and Fresh Weight Ismail Saadoun and Ziad Al-Ghazawi Department of Applied Biology, University of Sharjah, Sharjah, United Arab Emirates Department of Civil Engineering, College of Engineering, Jordan University of Science and Technology, Irbid - 0, Jordan Abstract: Tolerance of various plant seeds to different concentrations of diesel has been investigated. A noticeable decline in Cochorus olitorius seed germination of % was shown at 00 mg kg diesel or higher. However, seeds of Hordeum spontaneum, Triticum aestivum and Atriplex halimus showed a decline of less than 30 % at 00 mg kg diesel or higher with., 0 and 9.4% decline at 5000 mg kg, respectively. The effect of different diesel concentrations was also reflected on the length and fresh weight of sprouts of the tested plants with severe decline (> 50%) of C. olitorius sprouts' length and weight at 5000 mg/kg diesel as compared to the most resistant plant sprouts (T. aestivum) that showed < 5 % decline of both sprouts' length and fersh weight. It appears that the local seed plants (H. spontaneum, T. aestivum and A. halimus) have the ability to germinate with 60% or more at 5000 mg kg diesel. Careful selection of plant species to be used at a particular polluted site should be cautiously approached based on the actual soil and climate conditions and other characteristics of the site. Key words: Diesel Plant seeds Phytoremediation Soil INTRODUCTION biodegradation; phytodegradation; phytoextraction; phytovolatilization and hydraulic pumping [5]. The pollution with petroleum, heavy metals, An inventory of plant species in terrestrial and xenobiotics, organic compounds and other contaminants wetland environments in western Canada with a is a growing environmental concern that harms both demonstrated potential to phytoremediate or tolerate terrestrial and aquatic ecosystems. Bioremediation as a petroleum hydrocarbons was developed by Farrell et al. cleanup method and through the exploitation of the [6]. One of the search results generated by this database activities of microorganisms would degrade or attenuate is a list of plant species capable of degrading (or such contaminants. Phytoremediation as one of the assisting in the degradation of) a variety of petroleum developed and implemented technologies of hydrocarbons and which may have potential for bioremediation is another option for cleaning up phytoremediation efforts in western Canada. Novak environmental pollution which, focuses on the use of and AL-Ghazawi [7] reported that both Fescue grass and living green plants (trees, grasses and aquatic plants) for Squash can enhance the bioremediation of hydrocarbon the removal of contaminants and metals from soil, contaminated soils. Broad beans (Vicia faba) and lupine although some phytoremediation applications are (Lupine albus) plants were tested by Radwan et al. [3] believed to work through stimulation of rhizosphere and the results showed that V. faba tolerated up to 0% bacteria by the growing plant root []. For hydrocarbon crude oil (sand/crude oil, w/w). However, L. albus died contamination, terrestrial, aquatic and wetland plants and after three weeks of exposure to a 5% oil concentration. algae can be used for the phytoremediation process under Also, the leaflet areas of V. faba and L. albus, were specific cases and conditions [-4]. The specific respectively reduced by 40 and 3% at a concentration of mechanisms involved in phytoremediation include: % of oil. Other plants, such as Bermuda grass and Tall enhanced rhizosphere activity and subsequence fescue were also investigated for their capabilities to Corresponding Author: Ismail Saadoun, Department of Applied Biology, University of Sharjah, P.O. Box 77, Sharjah, UAE. Tel: , Fax:

2 Am-Euras. J. Agric. & Environ. Sci., 8 (): 67-7, 00 remediate petroleum sludge under the influence of was necessary to prepare the different concentrations of inorganic nitrogen and phosphorus fertilizers. diesel. Two hunded ml of 5000 ppm diesel was prepared About a 49% reduction of TPH occurred in the first six by disolving ml of evaporated diesel in 99 ml of months, but there were no significant differences between methylene chloride. This stock was used to prepare the the two species and the control (unvegetated). After one other diesel concentartions; 00, 00, 500, 000 and year, TPH was reduced by 68, 6 and 57% by Bermuda, 000 ppm. Methylene chloride and distilled water were fescue and control, respectively. Radwan et al. [3] used as controls. Two ml of each diesel concentartion, concluded that the optimal remediation was obtained by methylene chloride and water were added to the glass fertilization that produced a C:N:P ratio of 00::0.. AL- Petri dishes. Plates that have been treated with diesl or Ghazawi et al. [8] also tested seeds of two plants, methylene chloride were uncovered for 0 min at room Fescue grass (Cyndon dactylon) and Alfalfa (Medicago temperature. sativa) in their selection of plant seeds to resist diesel pollution as indicated by seed germination of these Plant Seeds: A total of 0 different plant seeds were plants. either kindly provided by the National Center for This investigation represent a preliminary Agricultural Research and Technology Transfer screening for tolerant local plant seeds exposed to (NCARTT/Ministry of Agriculture-Jordan) or varying levels of diesel fuel contamination. purchased from the local market. The seeds However, before starting a phytoremediation project, represent monocot or dicot plants and their viability determining the toxicity of the contamination toward the was provided from the source they are obtained from. plants is essential. Therefore, a successful approach Each seed type was given an alphabet letter (Table ). requires the selection of plant seeds that have high Two replicates from each type of seed were grown at resistance to the pollutant to be treated. For this reason, different diesel concentrations (0.0, 00, 00, 500, 000, this investigation aimed to initiate an inventory process 000 and 5000 mg kg ). The germinated seeds under in Jordan for plant species in terrestrial environment with these conditions are expected to be tolerant to diesel and a potential to tolerate high levels of petroleum thus may be recommended for phytoremediation of diesel contamination and screen these local plants or plant contaminated soils. However; growth on cotton is not the seeds for their resistance to high levels of diesel same as growth in soil and results of this study are only contamination to be recommended in future remediation first indication of diesel phytotoxicity of seeds under real of contaminated soils. soil conditions. MATERIALS AND METHODS Phytotoxicity and Indexing the Samples: An index was formulated to assign the sample number and diesel Preparation of Diesel: Five liters of diesel were purchased concentration. Letters were assigned to each plant seed. from Ramadan Gas Station/Irbid-Jordan. Ten ml of disel Digits 00, 0, 0, 05, 0, 0 and 50 were assigned to diesel were weighed then placed in a chemical fume hood for concentration of 0.00, 00, 00, 500, 000, 000 and evaporation at room temperature for 4 hours. After 5000 mg kg, respectively. For example, the A05 that, the remaining amount of diesel was measured in index refers to A plant, replicate number with diesel trem of volume (ml) and weight (gm). Diesel measurement concentration of 500 mg kg. Table : Viability of seeds of each plant type as compared to the viability being provided from the source Plant Common Name Source Viability % S Triticum durum Solid Horani Wheat Local Market 70 J Abelmoschus Escalentus Clemson Spineless (Oakra) NCARTT 85 M Var. sacharata Zea Maize (Corn) NCARTT 80 W Cochorus olitorius Jew s mallow (Molloukhia) Local Market 87 V Hordeum vulgare Barley Local Market 80 K Cucuvita pepo Slasil (Squash) NCARTT 00 L Phaseolus vulgaris Romano NCARTT 90 D Triticum aestivum - NCARTT 00 E Atriplex halimus - NCARTT 85 F Hordeum spontaneum - NCARTT 90 NCARTT: National Center for Agricultural Research and Technology Transfer (Ministry of Agriculture-Jordan) Number of plant seeds being used was 0. Number of other plant seeds was 5 68

3 Am-Euras. J. Agric. & Environ. Sci., 8 (): 67-7, 00 Two grams of cotton were placed in glass Petri RESULTS AND DISCUSSION dishes of cm diameter and the required volume of diesel was added. Diesel was dissolved in Diesel Measurements: Initial volume of diesel that was methylene chloride to provide larger volume and used for preparation of the different concentration was thus make sure that the diesel is fully and 0 ml. This volume weighed 8. gm. After evaporation for homogeneously distributed all over the entire cotton. 4 hrs, the volume was reduced to 9 ml and the weight After adding the diesel contamination, the dishes were was reduced to 7.6 gm. opened inside a fume hood to evaporate the methylene chloride. The zero diesel concentration was used as a Viability of Seeds: Viability of seeds of each plant type control to determine the viability of the seeds. Seeds (0- was determined by counting the number of germinated 5) of each species were introduced to each dish and seeds from the plates being treated with water then ml of sterile distilled water added. The dishes (Table, Fig. ). The plant species were chosen as they were sealed with a parafilm and incubated in the dark at have considerably deep roots and long life span. room temperature to simulate below ground soil In addition, these plant species have not previously conditions. After 0 days, the dishes were opened and the assessed for tolerance of diesel fuel contamination. germinated seeds quantified. Control Petri dishes includes seeds of each plant and ml of either sterile distilled water Toxicity of Diesel Towards Plant Seeds: The potential of or methylene chloride. plant seeds to germinate at different concentrations of diesel is shown in Table. A noticeable decline in Incubation: All plates were incubated at room Cochorus olitorius seeds germination of % was temperature for 0 days. At days intervals, shown at 00 mg kg diesel or higher. However, seeds of plates were uncovered and sprayed 3 times with Hordeum spontaneum, Triticum aestivum and Atriplex tap water, physically observed for seed germination halimus showed more resistant to diesel with a decline or fungal contmination. After incubation, the of less than 30 % at 00 mg/kg diesel or higher. number of germinated seeds were counted, the Data indicated that seeds of Triticum aestivum were the length (mm) and weight (mg) of plant sprout were most resistant to diesel followed by seeds of Hordeum determined using a caliper and an analytical balance, spontaneum and Atriplex halimus with., 0 and 9.4% repectively. decline at 5000 mg/kg, respectively. Table : Germination of different plant seeds at different diesel concentration Diesel Concentration (Mg/Kg) Plant Seed Triticum durum I II Abelmoschus escalentus I II Var. sacharata I II Cochorus olitorius I II Hordeum vulgare I II Cucuvita pepo I II Phaseolus vulgaris I II Triticum aestivum I II Atriplex halimus I II Hordeum spontaneum I II diesel concentration represent treatment of seeds with distilled water I: Average number of germinated seeds; II: Average % of germinated seeds 69

4 Am-Euras. J. Agric. & Environ. Sci., 8 (): 67-7, 00 A (Barley, Hordeum vulgare) B (Solid Horani Wheat, Triticum durum) C (Clemson Spineless Oakra, Abelmoschus escalentus) D (Zea mays, Corn, Var. sacharata ) Fig. : Germination of different plant seeds at different diesel concentrations (mg/kg). A: (Barley, Hordeum vulgare); B (Solid Horani Wheat, Triticum durum); C: (Clemson Spineless Oakra, Abelmoschus escalentus; D: (Zea Maize, Corn, Var. Sacharata) Table 3: Length (mm) and weight (mg) of each tested plant sprout at different diesel concentration Diesel Concentration (Mg/Kg) Plant Seed Triticum durum I II Abelmoschus escalentus I II Var. sacharata I II Cochorus olitorius I II Hordeum vulgare I II Cucuvita pepo I II Phaseolus vulgaris I UD UD II UD UD Triticum aestivum I II Atriplex halimus I II Hordeum spontaneum I II diesel concentration represent treatment of seeds with distilled water I: Average length (mm) of plant sprout; II: Average fresh weight (mg) of plant sprout 3 UD: un determined 70

5 Am-Euras. J. Agric. & Environ. Sci., 8 (): 67-7, 00 Table 4: Comparison of the most sensitive and resistant plant seeds to different diesel concentration Diesel Concentration (Mg/Kg) Plant Seed Cochorus olitorius I II III IV V VI VII Triticum aestivum I II III IV V VI VII Atriplex halimus I II III IV V VI VII Hordeum spontaneum I II III IV V VI VII diesel concentration represent treatment of seeds with distilled water I: Average number of germinated seeds; II: Average % of germinated seeds, III: % decrease in seed germination as compared with control (0.0 diesel), IV: Average length (mm) of plant sprout; V: % decrease in sprouts' length as compared with control (0.0 diesel); VI: Average fresh weight (mg) of plant sprout; VII: % decrease in sprouts' fresh weight as compared with control (0.0 diesel) Fig. : Growth of germinants of different plant seeds at at different diesel concentrations (mg/kg) as indicated by the length of the sprout. A: (Solid Horani Wheat, Triticum durum); B: B (Barley, Hordeum vulgare) The effect of different diesel concentrations showed < 5 % decline of both sprouts' length and was also reflected on the length and fresh weight of fersh weight (Table 3 and 4, Fig. ). It appears that sprouts of the tested plants with severe decline the local seed plants (Hordeum spontaneum, (> 50%) of Cochorus olitorius sprouts' length and Triticum aestivum and Atriplex halimus) have weight at 5000 mg/kg diesel as compared to the most the ability to germinate with 60% or more at resistant plant sprouts (Triticum aestivum) that 5000 mg kg diesel. 7

6 Am-Euras. J. Agric. & Environ. Sci., 8 (): 67-7, 00 Local seed plants (Hordeum spontaneum, 3. Radwan, S.S., H. Awadhu and I.M. El-Nemr, Triticum aestivum and Atriplex halimus) could 000. Cropping as a phytoremediation practice for tolerate high amounts of diesel. Based on the actual oily desert soil with reference to crop safety as food. soil and climate conditions and other characteristics Int. J. Phytoremed, : of a particular polluted site, selection of these plant 4. Siciliano, S.D. and C. Greer, 000. Plant-bacterial species to be used for soil remediation should be combinations to phytoremediate soil contaminated cautiously approached. with high concentrations of, 4, 6-Trinitrotolene. J. Environ. Quality, 9: ACKNOWLEDGMENTS 5. U.S. Army Corps of Engineers (USACOE), 997. Waterways Experiment Station. Appreciation is extended to University of Sharjah Phytoremediation: The Process. pp: 5. Online. and Jordan University of Science and Technology for Internet. July 998. Available: administrative support. el/phyto/ backgrnd.html. 6. Farrell, R.E., C.M. Frick and J.J. Germida, 000. REFERENCES PhytoPet : a Database of Plants That Play a Role in the Phytoremediation of Petroleum Hydrocarbons.. Glass, D.J., 005. Commercial use of genetically pp: in Proceedings of the Second modified organisms (GMOs) in bioremediation and Phytoremediation Technical Seminar, Environment phytoremediation. In: Bioremediation of Aquatic Canada, Ottawa. and Terrestrial Ecosystems, Eds., M. Fingerman, 7. Novak, J. and Z. AL-Ghazawi, 997. Plants-assisted R. Nagabhushanam, Science Publishers, Enfield Bioremediation of hydrocarbon contaminated soils, (NH), USA, pp: Proceedings of the mid-atlantic hazardous waste. Nedumuri, K.V., R.S. Govundaraju, M.K. Banks, conference, Blacksburg, Virginia. A.P. Schwab and Z. Chen, 000. Evaluation of 8. Al-Ghazawi, Z., I. Saadoun and A. Al-Shak ah, 005. phytoremediation for field scale degradation Selection of bacteria and plant seeds to grow on of total petroleum hydrocarbons. J. Environ. Eng., diesel fuel to be used in remediation of diesel 6: contaminated soils. J. Basic Microbiol., 45: