Background: Cement industry is one of the most polluting industry, that emits numerous pollutants as dust and heavy metals. Plants growing in the vicinity of cement industry are greatly affected by the pollutants emitted from this industry, so these plants could be used as air pollution monitoring. Materials and Methods: Cynanchum acutum plant was growing at the vicinity of studied factory and its growth, physiological and anatomical features investigated as biomonitoring for cement factory pollutants. Results: All plant growth attributes (shoot length, branches number, root length, leaf area and dry weight of shoot and root) at plant growing in the vicinity of the factory (polluted site) by 54.14, 61.16, 60, 60.01, 43.11 and 70%, respectively as compared to control site (250 m away from the factory). Chlorophyll a, b and carotenoids as well as total soluble sugars and carbohydrates were reduced by 39.69, 18.61 and 28.57% as well as 56.03 and 43.48%, respectively at polluted sites as compared to control site. Anatomical investigation revealed that there was a reduction in the palisade and spongy parenchyma, reduction in the xylem vessels and increases in the density of phloem tissues. The estimated heavy metals (zinc, nickel, cadmium and lead) in soil and plant leaves showed a significant increases at polluted site as compared to control site. The dust amount on the plant leaves showed the same trend of heavy metals. Conclusion: Cement dust pollution showed a significant alterations in growth, physiological and anatomical features of Cynanchum acutum plant, which qualify it to monitor the cement pollution. Plants growing in the vicinity of the pollution is a best tool for monitoring pollution, where these plants exposed enough to the emitted pollutants. On the contrary, the air around the factory move by wind and the pollutants concentrations become poor reprehensive for pollution.
How to cite this article:
Ghada Abd Allah EL-Sherbeny and Ahmed Abdullah Najm, 2016. Growth, Physiological and Anatomical Behaviour of Cynanchum acutum in Response to Cement Dust Pollution. Journal of Environmental Science and Technology, 9: 345-353.
Cement is one of the most widely used materials throughout the globe. Its persistent production plays a hazardous role in production of air pollutants as sulphur dioxide, nitrogen oxides and dust which disturb the environment. Cement industry is considered from the 17 most polluting industries listed by the Central Pollution Control Board (CPCB). The pollutants emitted from cement factories affect the whole ecosystem around the factories including settlement of the pollutants as visible clouds on the soil and vegetation1,2. Physiological disorders such as reduction of photosynthesis and respiration rates of leaves in addition to the reduction in growth rate and productivity were recorded as a result of the dust produced from cement industry3-5.
Environmental pollution with heavy metals is a major problem globally as they are stable and most of them are toxic to living organisms. The most recorded heavy metals with potential hazards and occurrences in soils are cadmium, chromium, lead, zinc, iron and copper6,7. Cement industry release such these heavy metals into the surrounding environment, so soils, plants and residents along the polluted areas are subjected to more contamination with heavy metals which could be carried on the dust particles8,9.
In Egypt, the problem of air pollution is of great concern. The huge increase in population accompanied by increase of urban expansion and industrialization as cement industry lead to substantial increase in air pollution10.
Assessment of plant behaviour and soil quality nearby the cement factories is a good tool to evaluate the impacts of this industry. This tool is more expressive than estimation of ambient air pollutants only which is transferred by wind to other places and directions, meanwhile vegetation and soil spend more time in the place. The behaviour and responses of plant to air pollution were used in the air pollution monitoring by some researches11,12. Several studies were reported on the impact of the cement dust on soil properties and plant9,13-17.
Cynanchum acutum L. is a climber shrub belonging to family Asclepiadaceae. It is widely distributed in Egypt in the Nile region, Mediterranean coastal region and oases18. The Aim of this study is to evaluate the changes in growth, physiological and anatomical features of Cynanchum acutum in response to cement dust pollution.
MATERIALS AND METHODS
Sampling: Plant and soil samples were taken at different distances from the factory located at Helwan city. The first distance was at the vicinity of the factory representing the highest degree of pollution (polluted site), the second was at about 100 m away from the factory and the third was at about 250 m away from the factory representing the lowest degree of pollution and called control site which is compared with the first distance.
Soil analysis: Soil samples were collected from a depth of 0-20 cm. The samples were mixed well, spread over sheets of paper and left to dry in the air. Dried soils were passed through a 2 mm sieve and were then packed in paper bags analysis. Organic carbon (OC) was determined by Walkely and Black rapid titration assay. Calcium carbonates (CaCO3) was determined by titration with 0.5 M sodium hydroxide according to Jackson19.
Metal concentrations (zinc, nickel, cadmium and lead) in soil and plant leaves were estimated according to Allens20 as follow, the samples were dried at 60°C till constant dry weight. The dried samples were ground to fine powder and stored in a tightly closed paper bag until metals measurement. About 0.1 g of each dried powder was digested by using concentrated HNO3 and heated gently until the solution turned quite clear. The clear samples were made up to a known volume using distilled water. Then the samples measured by a flame atomic absorption spectrophotometer (A Perkin-Elmer, Model 2380, USA).
Photosynthetic pigment: About 1 g of fresh leaves was ground in a mortar with 10 mL of absolute acetone using a quartz sand pinch. A little volume of acetone was initially added to start grinding process and then more solvent added in small amounts while continuing to grind the leaves. The extract was centrifuged for 3-5 min using bench top centrifuge at 5000 rpm. The extract was transferred into a 10 mL graduated cylinder using Pasteur pipette. An aliquot of the supernatant was transferred to a 1 cm cuvette and the absorbance readings were recorded against a solvent blank using UV-visible spectrophotometer at wavelengths of 662, 645 and 470 nm for determination of the photosynthetic pigments concentrations like chlorophyll a, b and carotenoids using the formula described by Lichtenthaler21.
Pigments quantification (in case using 100% acetone):
|•||Chl-a (μg mL1) = 11.24 A662-2.04 A645|
|•||Chl-b (μg mL1) = 20.13 A645-4.19 A662|
|•||Carotenoids = (1000 A470-1.90 Ca-63.14 Cb)/214|
Estimation of total soluble sugars and total carbohydrates content: About 0.5 g of the air dried plant material was soaked in 10 mL of 80% (v/v) ethanol and left overnight at room temperature with periodic shaking. The mixture was filtered and the filtrate was kept in refrigerator for further analysis. For estimation of the non-soluble carbohydrates content, the residue was washed several times using 80% methanol to remove any soluble sugars. After that, 5 mL distilled water and 6.5 mL perchloric acid (52%) were added to the residue, then the mixture was centrifuged at 5000 rpm and the supernatant filtered using Whatman filter paper No. 5 m. These procedures were repeated several times and the resulted supernatant was completed up to 100 mL with distilled water22. About 0.1 mL of the ethanolic extract was mixed with 3 mL of the freshly prepared anthrone reagent (150 mg anthrone reagent+100 mL sulphuric acid (98%), boiling in water bath and cooling. The absorbance was measured at 625 nm using UV-vis. Spectrophotometer (Model 21 D). The total soluble sugars and total soluble carbohydrates were estimated using standard curve of glucose23.
Analysis of plants anatomical features: The anatomical description of the studied plants was done according to the methods described by Johansen24 and modified by Peacock and Bradbury25. Examination and photographing step as follow; perfect cross sections were selected for recording observation. The microscope used was a full automatic Olympus microscope. Sections were photographed at 40X, 100X and 400X.
Dust deposition: The plant leaves were washed then the water containing dust was filtered in a weighted filter paper (w1). The filter paper with dust was dried in oven until constant weight (w2). The dust amount equal the difference between w1 and w2 (gram per plant).
Statistical analysis: One way analysis of variance (ANOVA) was applied to assess the significance of variation between means by Turkeys HSD at p≤0.05 using SPSS version 20.
RESULTS AND DISCUSSION
Effect of cement dust pollution on plant growth attributes: The results in Table 1 showed the plant growth attributes of Cynanchum acutum at different distances from cement factories.
The highest shoot length of C. acutum was recorded at the control sites (67.60±7.44 cm), while the lowest value was recorded at the polluted sites (31.00±3.94 cm). The shoot length of C. acutum showed a significant reduction (p≤0.01) at the polluted sites by 54.14% of the control sites. The number of branches of C. acutum exhibited the highest value of 24.20±4.44 at the control sites, meanwhile the lowest number of branches was recorded at the polluted sites (9.4±1.67). Furthermore, there was a significant difference (p≤0.001) between the number of branches at polluted sites and control sites, where there was a reduction by 61.16% in the number of branches between polluted and control site. Concerning the root length, it recorded the highest value of 14.00±1.41 cm at control sites, whereas the plants growing at the polluted sites have the lowest root length of 5.60±0.89 cm. The root length was significantly (p≤0.05) reduced by 60% in plants nearest to the cement factory. Regarding the leaf area of C. acutum plant at polluted sites it was 5.18±1.33 cm2, while it was 9.30±3.24 cm2 at 100 m distance from polluted site and 12.97±2.94 cm2 at the control site. Also, it is observed that, there was a significant difference (p≤0.05) between the C. acutum plant growing in polluted sites and control site, where it reduced by 60.01% at the polluted sites.
In addition, the obtained data revealed that the dry weight of C. acutum shoot ranged from the maximum value of 5.08±0.26 g recorded at control sites to minimum value of 2.89±0.18 g at polluted site. It was observed that there was a significant reduction by 43.11% in polluted site from the control site (p≤0.05). On the other side, the highest dry weight of root was exhibited in control plants with a value of 2.06±0.23 g, while the lowest value of 0.60±0.25 g was recorded at the polluted sites.
|Table 1:||Growth attributes of Cynanchum acutum at different distances from the cement factory|
|**Significant at p≤0.01, ***Significant at p≤0.001, bars labelled with different letters are significantly different (Turkeys HSD, p≤0.05)|
It is clear that there was a significant difference (p≤0.05) between the studied sites where plant of the polluted site was reduced by 70% comparing to plant of control site.
The present results of studied growth attributes were confirmed by some researchers who studied effect of cement dust on growth and morphology of some pans as Prasad and Inamdar26 on Vigna mungo, Iqbal and Shafiq13 on Carissa carandas and Azadirachta indica and Chaurasia et al.17 on Arachis hypogaea. This may be attributed to alkaline properties of cement particles that deposits on the neighbouring soils changing its features which intern cause significant changes in vegetation growth13,27-29.
Effect of cement dust pollution on photosynthetic pigments: The illustrated data in Fig. 1 revealed that Chlorophyll a content in C. acutum plant recorded the highest value of 1.94±0.23 mg g1 fresh weight at the control sites, while it was 1.32±0.24 mg g1 at 100 m distance from factory site and 1.17±0.15 mg g1 fresh weight at the polluted sites. The Chl a content increases as the distance from industry increases, where there was a significant difference between the different distances and a significant reduction of 39.69% in chlorophyll a was recorded in the samples from the polluted sites in comparison to control.
The content of chlorophyll b was 0.70±0.05 mg g1 in the cement factories polluted sites, while it was 0.82±0.09 mg g1 at 100 m distance from polluted site and 0.86±0.12 mg g1 fresh weight at the control site. It is clear that there was a significant difference between the studied sites, whereas the distance increase the concentration of Chl b increase and a significant reduction of 18.61% in chlorophyll b in polluted sites from the control was observed.
The content of total carotenoids in C. acutum cement factory polluted sites was 0.30±0.01 mg g1 fresh weight while it was 0.34±0.05 mg g1 at 100 m distance from polluted site and 0.42±0.10 mg g1 fresh weight at the control site.
|Fig. 1:||Effect of cement dust pollution on photosynthetic pigments content of Cynanchum acutum at different distances|
Thus a significant reduction of 28.57% in carotenoids was estimated in the plants of the polluted sites from those of the control.
Total chlorophylls and carotenoids are considered as the main core of energy production in green plants and their amounts are significantly altered because of the environmental impacts on plant metabolism30. Air pollution is considered as one of the main factors that impose damaging effect on the photosynthetic pigments. Under environmental stress chlorophyll pigments might undergo several photochemical reactions such as oxidation, reduction and reversible bleaching31,32.
The significant reduction in chlorophyll a , chlorophyll b and carotenoids in C. acutum growing in the vicinity of cement factory comparing to that growing at control sites. be interpreted as follow: (1) In the deposition of fly ash and dust on the surface of plant leaves act as sunscreen and reduce interception of incident light as well as clogging the stomatal opening33, which cause gaseous exchange interfering Borka34. This might lead to increase in leaf temperatures that might retard the synthesis of chlorophyll35 and (2) The incorporation of cement dust into foliar tissue damages the chloroplast and consequently, reduced the chlorophyll "a" and "b" as well as total chlorophyll content in the plants nears the industry36,37. The same behaviour was observed by Pandey et al.38, Abdel-Rahman and Ibrahim39 and Kumar and Thambavani2. In addition, a reduction in carotenoid content of plants growing in polluted locations was reported by Joshi and Swami40, Joshi et al.41 and Giri et al.32.
Effect of cement dust pollution on total soluble sugars and total carbohydrates: The data in Fig. 2 showed that the total soluble sugars of C. acutum at the control site recorded the highest value of 184.54 mg g1 dry weight, while it was 131.24 mg g1 at 60 m distance from polluted site and the lowest value was 81.15 mg g1 dry weight at the polluted site.
|Fig. 2:||Effect of cement dust pollution on total soluble sugars and carbohydrates content of Cynanchum acutum at different distances|
It is clear from the results that, there was a significant reduction of 56.03% in total soluble sugars of C. acutum of the polluted sites comparing to that of the control site. On the other hand, the total carbohydrates content (Fig. 2) was 325 mg g1 dry weight in C. acutum of the polluted sites while it was 575 mg g1 dry weight at the control site . It is obvious from the obtained data that total carbohydrates content showed a significant reduction of 43.48% in the plant of the control site comparing to the polluted sites.
Soluble sugars play important roles in plants, where they are compartments of the plant structure and sources of energy in all organisms42-44. In this study the significant reduction in soluble sugars content of C. acutum plant at the polluted site may be due to the increase in respiration rate and decrease in fixation of CO2 due to chlorophyll deterioration, as well as pollutants from cement industry like sulphur oxides and nitrogen oxides might cause more depletion of total soluble sugars in plants grown in polluted areas45,32.
Effect of cement dust pollution on the anatomy of C. acutum: Anatomical characteristics of C. acutum leaf were investigated at polluted sites and control site. Leaf cross- section (Fig. 3a) is composed of adaxial and abaxial epidermis of cubical and some conical shaped cells. The lower epidermis of the midrib is projecting form the blade. This projection consists of a group of collenchymatic cells and represent characteristic feature of the leaf. The mesophyll is bifacial, differentiated into palisade and spongy parenchyma. The palisade tissue is bi-layered and lies beneath the upper epidermis, consists of vertically elongated cells and possesses relatively few intercellular spaces. Spongy tissue situated below the palisade parenchyma and is loosely arranged. The vascular bundle of the midrib composed of lignified radiating xylem vessels arranged in vertical rows.
Owing to cement dust emitted from cement factory, the cross-section in C. acutum leaf (Fig. 3b) showed that, there were collapsed cells appeared in the mesophyll tissues; reduction in the palisade and spongy parenchyma as well as in the size of chloroplasts. Concerning the vascular vessels, there was a reduction in the xylem vessels and increases in the density of phloem tissues. These results confirmed by those obtained by Gostin46, El-Khatib et al.47 and Sukumaran48.
Effect of cement dust pollution on soil properties and heavy metal content: Analysis of soil properties (Table 2) showed that the Organic Carbon (OC) content was increased by increase the distance from the factory which varied from 0.32% at the polluted sites to 0.55% at control sites. Meanwhile calcium carbonate (CaCO3) content showed the reverse trend of OC and ranged from 10.2% at the polluted site to 6.8% at control site. The pH was alkaline to slightly alkaline and fluctuated from 9.53% at the polluted site to 7.86 at control site. Electric Conductivity (EC) was increased at the polluted site and varied from 2190 μS cm1 at polluted site to 1590 μS cm1 at control site. Cement dust analysis indicated that it composed mainly of limestone (80%) and characterized by alkaline pH and elevated salinity16.
|Fig. 3(a-b):||Cross section in leaf of Cynanchum acutum growing at (a) Control site and (b) Polluted site|
|Table 2:||Properties of soil samples at different distances from the cement factory|
|***Significant at p≤0.001, ns: Not significant (p>0.05)|
The obtained results in Fig. 4a showed that the levels of Zn, Ni, Cd and Pb in the soil in the vicinity of cement factory at various distances exhibited a significant variation. The lowest values of heavy metals concentrations were recorded at the control site (27.45, 18.52, 0.15 and 8.56 μg g1, respectively); while the highest ones were recorded at the polluted cement factories site (84.09, 39.81, 0.42 and 18.5 μg g1, respectively). The heavy metals content in the soil significantly decreases as the distance from industry increases.
Effect of cement dust pollution on the heavy metals content of C. acutum: The average heavy metals content in C. acutum leaves at the control sites exhibited the lowest levels of Zn, Ni, Cd and Pb (9.44, 12.81, 0.09 and 0.94 μg g1, respectively), meanwhile at the polluted site attained the highest values were recorded (30.65, 35.7, 0.26 and 3.02 μg g1, respectively). It is obvious from the obtained data that, there were significant differences in the heavy metals content in the leaves of the studied plants at control and polluted site (Fig. 4b).
The cement dust contain mixture of metals that impose many impacts on the plants includes yield reduction and adversely affect leaf area, seed germination and water content50-52. These metals cause several effects including reduction in plant growth, seed yield, pollen fertility and total protein levels in addition to other cytogenetic effects39,50-55. Wild plants can be used as biomonitors for the metals in the air due to their ability for heavy metals accumulation11,12,56-58.
Dust deposits: It is clear from the illustrated results in Fig. 5 that there was a highly significant difference (p≤0.001) in the amount of dust on the C. acutum leaves. Where, the highest amount of dust was on plant leaves of polluted site (1.48 g per plant), meanwhile the lowest amount was recorded on the plant leaves of control site (0.45 g per plant).
In this study, the estimated amount of dust on C. acutum leaf surface showed significant increase with decrease of the distances from the cement factory. Van Jaarsveld59 reported that the atmosphere gained approximately 30 million tons of dust each year. The most widespread sources of dust are cement and brick factories, power plants, agricultural activities and heavy vehicles60. Dust particles have harmful effects on plants where as mentioned before it act as sun screen which intern cause reduction in photosynthesis and decline in plant growth61.
|Fig. 4(a-b):||Effect of cement dust pollution on heavy metals content (μg g1) of (a) Soil and (b) Cynanchum acutum leaves at different distances|
|Fig. 5:||Effect of cement dust pollution on the dust amount on Cynanchum acutum leaves at different distances|
In addition Farmer62 revealed that dust deposition on the plant leaf increase their temperature which, in turn, increase the susceptibility of plant to drought.
Cement dust pollution showed a significant alterations in growth, physiological and anatomical features of Cynanchum acutum plant which qualify it to monitor the cement pollution. The soil properties in the vicinity of cement factories were changed and acquired the properties of cement dust which intern change the plant features. In addition, the heavy metals concentrations increased in plant leaves and soil nearby the cement factories.
Abdel-Rahman, A.M. and M.M. Ibrahim, 2012. Effect of cement dust deposition on physiological behaviors of some halophytes in the salt marshes of Red Sea. Egypt. Acad. J. Boil. Sci., 3: 1-11.
Ade-Ademilua, O.E. and C.E. Umebese, 2007. The growth of Phaseolus vulgaris L. cv. Ife Brown (Leguminosae) in a cement site rich in heavy metals. Pak. J. Biol. Sci., 10: 182-185.
Akoto, O., J.H. Ephraim and G. Darko, 2008. Heavy metals pollution in surface soils in the vicinity of abundant railway servicing workshop in Kumasi, Ghana. Int. J. Environ. Res., 2: 359-364.
Al-Khashman, O.A. and R.A. Shawabkeh, 2006. Metals distribution in soils around the cement factory in Southern Jordan. Environ. Pollut., 140: 387-394.
Al-Omran, A.M., S.E. El-Maghraby, M.E.A. Nadeem, A.M. El-Eter and S.M.I. Al-Qahtani, 2011. Impact of Cement Dust on Some Soil Properties Around the Cement Factory in Al-Hasa Oasis, Saudi Arabia. Am.-Eurasian J. Agric. Environ. Sci., 11: 840-846.
Allens, S.E., 1989. Chemical Analysis of Ecological Materials. 2nd Edn., Blackwell Scientific Publications, Oxford, UK., ISBN: 9780632017423, Pages: 368.
Alloway, J.B., 1995. Soil Pollution and Land Contamination. In: Pollution: Causes, Effects and Control, Harrison, R.M. (Ed.). The Royal Society of Chemistry, Cambridge, pp: 352-376.
Amal, M.F. and M.M. Migahid, 2011. Effect of cement-kiln dust pollution on the vegetation in the Western Mediterranean Desert of Egypt. Int. Scholarly Sci. Res. Innov., 5: 480-486.
Asubiojo, O.I., P.O. Aina, A.F. Oluwole, W. Arshed, O.A. Akande and N.M. Spyrou, 1991. Effects of cement production on the elemental composition of soils in the neighborhood of two cement factories. Water Air Soil Pollut., 57: 819-828.
Borka, G., 1980. The effect of cement dust pollution on growth and metabolism of Helianthus annuus. Environ. Pollut. Series A Ecol. Biol., 22: 75-79.
Chaturvedi, R.K., S. Prasad, S. Rana, S.M. Obaidullah, V. Pandey and H. Singh, 2013. Effect of dust load on the leaf attributes of the tree species growing along the roadside. Environ. Monit. Assess., 185: 383-391.
Chauhan, A. and P.C. Joshi, 2010. Effect of ambient air pollutants on wheat and mustard crops growing in the vicinity of urban and industrial areas. N. Y. Sci. J., 3: 52-60.
Chaurasia, S., A. Karwariya and A.D. Gupta, 2013. Effect of cement industry pollution on chlorophyll content of some crops at Kodinar, Gujarat, India. Proc. Int. Acad. Ecol. Environ. Sci., 3: 288-295.
Cipurkovic, A., I. Trumic, Z. Hodzic, V. Selimbasic and A. Djozic, 2014. Distribution of heavy metals in Portland cement production process. Adv. Applied Sci. Res., 5: 252-259.
Davison, A.W. and J. Blakemore, 1976. Factors Determining Fluoride Accumulation in Forage. In: Effects of Air Pollutions on Plants, Mansfield, T.A. (Ed.)., Cambridge University Press, Cambridge, pp: 17-30.
De Paula Filho, F.J., R.V. Marins, L.D. de Lacerda, J.E. Aguiar and T.F. Peres, 2015. Background values for evaluation of heavy metal contamination in sediments in the Parnaiba River Delta estuary, NE/Brazil. Mar. Pollut. Bull., 91: 424-428.
El-Katony, T.M., M.A. El-Bemerdash and S.R. Dawoud, 2006. Impact of air pollution on accumulation of heavy metals in leaves of the plants Eucalyptus camaldulensis (Dehnhardt.) and Ficus retusa (L.). Egypt. J. Bot., 46: 47-64.
El-Khatib, A., K.N. Al-Sayed and N. Youssef, 2011. Bio-monitoring of airborne dust particles pollutants by Morpho-anatomical reactions of urban tree leaves under dry climate. Egypt. J. Bot., 51: 1-12.
Farmer, A.M., 1993. The effects of dust on vegetation-a review. Environ. Pollut., 79: 63-75.
Ghrefat, H. and N. Yusuf, 2006. Assessing Mn, Fe, Cu, Zn and Cd pollution in bottom sediments of Wadi Al-Arab Dam, Jordan. Chemosphere, 65: 2114-2121.
Giri, S., D. Shrivastava, K. Deshmukh and P. Dubey, 2013. Effect of air pollution on chlorophyll content of leaves. Curr. Agric. Res. J., 1: 93-98.
Gordon, C., E.O. Darko, M.A. Addo and B.J.B. Nyarko, 2013. Contamination of soils and loss of productivity of Cowpea (Vigna unguiculata L.) caused by cement dust pollution. Int. J. Res. Chem. Environ., 3: 272-282.
Gostin, I.N., 2009. Air pollution effects on the leaf structure of some Fabaceae species. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, 37: 57-63.
Hassan, M.M., M.G. Osman, M.M.M. Ahmed, K.G. Abdalaleem, M.E. Abdelgain and A.G.T. Babiker, 2011. Tissue culture technique as new approach to combat Striga hermonthica. Adv. Environ. Biol., 5: 2122-2128.
Iqbal, M.Z. and M. Shafiq, 2001. Periodical effect of cement dust pollution on the growth of some plant species. Turk. J. Bot., 25: 19-24.
Jackson, M.L., 1962. Soil Chemical Analysis. Constable Co. Ltd., London, Pages: 296.
Johansen, D.A., 1940. Plant Microtechnique. McGraw-Hill, New York, USA., Pages: 523.
Joshi, N., A. Chauhan and P.C. Joshi, 2009. Impact of industrial air pollutants on some biochemical parameters and yield in wheat and mustard plants. Environmentalist, 29: 398-404.
Joshi, P.C. and A. Swami, 2007. Physiological responses of some tree species under roadside automobile pollution stress around city of Haridwar, India. Environmentalist, 27: 365-374.
Khamparia, A., S.K. Chattergee and G.D. Sharma, 2012. Assessment on effect of cement dust pollution on soil health. J. Environ. Res. Dev., 7: 368-374.
Kumar, R.S. and D.S. Thambavani, 2012. Effect of cement dust deposition on physiological behaviors of some selected plant species. Int. J. Sci. Technol. Res., 1: 98-105.
Kumar, S.S., N.A. Singh, V. Kumar, B. Sunisha, S. Preeti, S. Deepali and S.R. Nath, 2008. Impact of dust emission on plant vegetation in the vicinity of cement plant. Environ. Eng. Manage. J., 7: 31-35.
Lichtenthaler, H.K., 1987. Chlorophylls and carotenoids: Pigments of photosynthetic biomembranes. Methods Enzymol., 148: 350-382.
Mishra, S. and S.B. Agrawal, 2006. Interactive effects between supplemental ultraviolet-B radiation and heavy metals on the growth and biochemical characteristics of Spinacia oleracea L. Braz. J. Plant Physiol., 18: 307-314.
Morghom, L.O., N.A. Darid, H.A. Sreiweel and A. Soliman, 2000. Effect of volatile cement dust on the soil properties surrounding the area around cement factories. Proceedings of the 11th International Cement Conference, November 13-16, 2000, Hammamet, Tunis, pp: 800-.
Naya, L., R. Ladrera, J. Ramos, E.M. Gonzalez, C. Arrese-Igor, F.R. Minchin and M. Becana, 2007. The response of carbon metabolism and antioxidant defenses of alfalfa nodules to drought stress and to the subsequent recovery of plants. Plant Physiol., 144: 1104-1114.
Ogunbileje, J.O., V.M. Sadagoparamanujam, J.I. Anetor, E.O. Farombi, O.M. Akinosun and A.O. Okorodudu, 2013. Lead, mercury, cadmium, chromium, nickel, copper, zinc, calcium, iron, manganese and chromium (VI) levels in Nigeria and United States of America cement dust. Chemosphere, 90: 2743-2749.
Pandey, D.D., A.K. Sinha and P. Kumar, 1998. Impact of stone crusher dust pollution on Cicer arietinum. Bio J., 10: 105-110.
Peacock, P. and S. Bradbury, 1973. Peacock's Elementary Micro-Technique. 4th Edn., Edward Arnold Publishers, London, UK.
Petrova, S., L. Yurukova and I. Velcheva, 2013. Taraxacum officinale as a biomonitor of metals and toxic elements (Plovdiv, Bulgaria). Bulgarian J. Agric. Sci., 19: 241-247.
Prajapati, S.K. and B.D. Tripathi, 2008. Seasonal variation of leaf dust accumulation and pigment content in plant species exposed to urban particulates pollution. J. Environ. Qual., 37: 865-870.
Prasad, M.S.V. and J.A. Inamdar, 1991. Effect of cement kiln dust pollution on growth and yield of Vigna spp. Indian J. Ecol., 18: 91-94.
Quesada-Moraga, E., B.B. Landa, F.J. Munoz-Ledesma, R.M. Jimenez-Diaz and C. Santiago-Alvarez, 2006. Endophytic colonisation of opium poppy, Papaver somniferum, by an entomopathogenic Beauveria bassiana strain. Mycopathologia, 161: 323-329.
Raajasubramanian, D., P. Sundaramoorthy, L. Baskaran, K.S. Ganesh, Al.A. Chidambaram and M. Jeganathan, 2011. Cement dust pollution on growth and yield attributes of groundnut (Arachis hypogaea L.). Int. Multidisciplin. Res. J., 1: 31-36.
Rai, P.K., 2009. Heavy metal phytoremediation from aquatic ecosystems with special reference to macrophytes. Crit. Rev. Environ. Sci. Technol., 39: 697-753.
Sandelius, A., K. Naslund, A.S. Carlsson, H. Pleijel and G. Sellden, 1995. Exposure of spring wheat (Triticum aestivum) to ozone in open-top chambers. Effects on acyl lipid composition and chlorophyll content of flag leaves. New Phytol., 131: 231-239.
Schutzki, R.E. and B. Cregg, 2007. Abiotic plant disorders: Symptoms, signs and solutions: A diagnostic guide to problem solving. Extension Bulletin No. E-2996, Michigan State University Extension.
Shukla, J., V. Pandey, S.N. Singh, M. Yunus, N. Singh and K.J. Ahmad, 1990. Effect of cement dust on the growth and yield of Brassica campestris L. Environ. Pollut., 66: 81-88.
Shvaleva, A.L., F.C.E. Silva, E. Breia, L. Jouve and J.F. Hausman et al., 2006. Metabolic responses to water deficit in two Eucalyptus globulus clones with contrasting drought sensitivity. Tree Physiol., 26: 239-248.
Singh, S.N. and D.N. Rao, 1978. Effect of cement dust pollution on soil properties and on wheat plants. Indian J. Environ. Health, 20: 258-267.
Singh, S.N. and D.N. Rao, 1981. Certain responses of wheat plants to cement dust pollution. Environ. Pollut. Ser. A: Ecol. Biol., 24: 75-81.
Southgate, D.A.T., 1991. Determination of Food Carbohydrates. 2nd Edn., Elsevier Applied Science, London, pp: 136.
Sukumaran, D., 2014. Effect of air pollution on the anatomy some tropical plants. Applied Ecol. Environ. Sci., 2: 32-36.
Tackholm, V., 1974. Students Flora of Egypt. 2nd Edn., Anglo Egyptian Bookshop, Cairo, Egypt, Pages: 888.
Thayumanavan, B. and S. Sadasivam, 1984. Physicohemical basis for the preferential uses of certain rice varieties. Plant Foods Hum. Nutr., 34: 253-259.
Tripathi, A.K. and M. Gautam, 2007. Biochemical parameters of plants as indicators of air pollution. J. Environ. Biol., 28: 127-132.
Tripathi, R. and K. Girjesh, 2010. Genetic loss through heavy metal induced chromosomal stickiness in Grass pea. Caryologia: Int. J. Cytol. Cytosyst. Cytogen., 63: 223-228.
Van Jaarsveld, F., 2008. Characterising and mapping of wind transported sediment associated with opencast gypsum mining. M.Sc. Thesis, University of Stellenbosch, South Africa.
WHO., 2010. Quantifying Environmental Health Impacts. World Health Organization, Geneva, Switzerland.
Wagh, N.D., P.V. Shukla, S.B. Tambe and S.T. Ingle, 2006. Biological monitoring of roadside plants exposed to vehicular pollution in Jalgaon city. J. Environ. Biol., 27: 419-421.
Yahaya, T., J. Okpuzor and O.O. Esther, 2012. Investigation of cytotoxicity and mutagenicity of cement dust using Allium cepa test. Res. J. Mutagen., 2: 10-18.
Zerrouqi, Z., M. Sbaa, M. Oujidi, M. Elkharmouz, S. Bengamra and A. Zerrouqi, 2008. Assessment of cement's dust impact on the soil using principal component analysis and GIS. Int. J. Environ. Sci. Technol., 5: 125-134.