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Fecir Elinç, Esin Güvercin, Ali Rıza Demirkıran Agriculture Faculty, Soil Science Section, Kahramanmaraş-Turkey ABSTRACT In this study the wheat leaf samples at the beginning of the heading stage and the soils samples from the 0-20 cm depth collected together from the 26 representative farmer fields. Some properties of the soil samples and the heavy metal contents of the leaf samples were determined. The results obtained showed that the DTPA+TEA extractable Fe, Mn and Cu contents of the soils were in the sufficient levels for the crops growth. Whereas the zinc contents of the soils were low. Therefore the total Fe, Mn and Cu contents of the wheat leaves were sufficient, but the zinc contents of all the leaf samples were in the deficient level. The DTPA+TEA extractable lead contents of the soils were in the acceptable level, however the nickel contents of the soils slightly high. The total nickel contents of the leaves might be considered slightly higher than the suggested critical tolerance level of nickel for plants. According to the linear correlation analysis results the zinc contents of the wheat leaves decreased significantly by the increasing available phosphorus level of the soils. Although the available zinc levels of the soils were low, the total nickel contents of the leaves decreased by the increasing zinc level of the soils. Considering the results of the study it is to be suggested that it will to be useful to avoid the usage of excess level of phosphorous fertilizer to control the zinc deficiency and the nickel accumulation in the plant tissue. In this way the quality and the quantity of the crop yields are to be increased in the point of view public health. INTRODUCTION The research results showed that chemical elements in plant or plant parts are related to dependent variables such as yield (Macy 1936, Tyner 1947). Shear et al. (1948), indicated that if all other factors were constant, plant growth was a function of two nutrition variables, intensity and balance. Thus, maximum growth and yield occur only with beeing of optimum intensity and balance of nutrients. Leaf composition represent a measure of all environmental factors both internal and external which influenced nutrient accumulation by the plant. The possibility of using minimum values of an inorganic nutrient as a basis for determining deficiencies has been recognized for many decades. In this manner it was found that growth decreases when the concentration of any element in the leaves fall below a minimum value for different crops. Peck et al. (1969), showed that regression analysis as independent variables revealed several significant relationships which indicated that critical level of any particular nutrient varies with leaf levels of other nutrients. Briefly the level of nutrients absorbed by plants is related to the amount of available nutrients in the soil. Therefore the purpose of this study was to determine heavy metal contents of the soils and the wheat leaves surrounds of the Center and Türkoğlu towns in Kahramanmaraş. MATERIAL and METHODS The soil samples from the 0-20 cm depth and the wheat leaf samples at the beginning of the heading stage were collected together from the 26 representative farmer fields. After collecting, the soils were air dried and sieved from a 2 mm screen. The soil pH was determined with a soil:solution ratio of 1:2.5 (w:v) with deionized water, organic matter was determined by a modified Walkley-Black method, exchangeable calcium, magnesium, potassium and sodium were determined by neutral ammonium acetate (Jackson, 1962), calcium carbonate was determined by Schleaber-Procedure (Hızalan and Ünal, 1966) and available phosphorus were determined by sodium bicarbonate extraction (Olsen, 1954). The heavy metal concentrations of the soils, such as Fe, Mn, Zn, Cu, Ni and Pb were determined by 0.005 M DTPA+0.01 M TEA+0.1 M CaCI2 (pH=7.3) extraction solution (Lindsay and Norvell, 1969) with AAS Perkin Elmer 3110. The leaf samples dried at 700 C for 48 hour and grinded. The total Fe, Mn, Zn, Cu, Ni and Pb contents of the leaf samples determined in the dry ashed solutions of the leaf samples (Kacar, 1972) by using AAS Perkin Elmer 3110. The simple correlation analysis were used between concentrations of heavy metals in the wheat leaves and soils variables (Steel and Torrie, 1960). RESULTS and DISCUSSIONS Some properties and heavy metal levels of the soils: The results of the soil analyses summarized in the Table 1 for the two locations. As shown in the Table 1, the soils were alkali in the soil reaction, high level in calcium carbonate, medium level in organic matter. The exchangeable calcium and magnesium contents of the soils were high. The exchangeable potassium contents of the soils were high, except two soils. The soils had not sodium and salinity problems. The available phosphorus contents of the soils were high than the need of the wheat plant, except four soils in the Türkoğlu town.  The DTPA+TEA extractable heavy metal contents of the soils summarized in the Table 2. As shown in the Table 2, the extractable iron contents of the soils were ranged from 4.52 mg kg-1 to 16.54 mg kg-1 that were higher than the sufficient level of 4.5 mg kg-1 of the method. The extractable manganese contents of the soils were ranged from 0.61 mg kg-1 to 44.23 mg kg-1 that were higher than the sufficient level of 1 mg kg-1 of the method, except one soil. The extractable copper contents of the soils were ranged from 1.40 mg kg-1 to 3.07 mg kg-1 that were more than the 0.2 mg kg-1 sufficient level of the method. The zinc contents of the soils were ranged from 0.09 mg kg-1 to 1.23 mg kg-1 that were lover than the sufficient level of 1 mg kg-1 of the method, excepts two soils. The nickel contents of the soils were ranged from 1.09 mg kg-1 to 21.53 mg kg-1. Considering the maximum cumulative levels of 4.48-26.88 mg kg-1 nickel in soils given by Risser and Backer (1991) and the critical concentrations of nickel in the soils from 6 mg kg-1 to 112 mg kg-1 for different plants given by Ascher (1991) the nickel contents of the some soils were slightly high. The lead levels of the soils were ranged from 0.82 mg kg-1 to 1.61 mg kg-1. Considering the maximum cumulative levels of 44.8-268.8 mg kg-1 lead in soils (Risser and Backer, 1991) the lead contents of the soils were in the acceptable level.  The heavy metal contents of the wheat leaves: The heavy metal contents of the leaf samples presented in the Table 3. As shown in the Table 3, the average iron and manganese contents of the leaf samples taken from Center were higher than that of Türkoğlu. The five leaf samples had less than 50 mg kg-1 total iron, but according to the sufficient level of total iron 10-300 mg kg-1 for winter wheat given by Jones et al. (1991), the total iron contents of the leaves were sufficient for the yield. However this explanation, it is to be recommended to run researches on the iron status of the soils and on the iron contents of the other crops on the area for the quality and quantity of the crop yields.  The total manganese and copper contents of the leaves were in the sufficient ranges, except one sample for manganese, give by Lones et al., (1991) 16-200 mg kg-1 and 5-50 mg kg-1 for manganese and copper, respectively. The total zinc contents of the all leaf samples were in the deficiency level compared to the suggested sufficient ranges of zinc 21-70 mg kg-1 for the winter wheat given by Lones et al. (1991). In addition this the total zinc contents of the leaves were lover than the level of zinc crops need, for this reason it is to be recommended to pay attention on the zinc contents of the plants and available zinc contents of the soils on this region considering the public nourishment and the yields of crops. The total nickel levels in the leaves were high than the suggested tolerance level of 3 mg kg-1 for plants given by Risser and Backer (1990), but it was discussible according to the critical nickel concentrations in the different plants given by Asher (1991), which changed up to the plant space from 7 mg kg-1 to 56 mg kg-1 of total nickel in the tissue for bermuda grass and pangola grass, respectively. Although the two leaf samples contained 11.97 mg kg-1 and the three leaf samples contained 5.99 mg kg-1 total lead, the twenty one leaf samples had not contained the total lead. The relationships between the soil variables: The linear correlation coefficient analysis results of the soil variables given in the Table 4. As shown in the Table 4, the soil pH increased significantly by the rising calcium carbonate (r= 0.488*) and exchangeable calcium (r= 0.438*). The soil salinity increased by the rising exchangeable magnesium (r= 0.654***) and sodium (r= 0.407*). The exchangeable calcium was in relation with the percent calcium carbonate (r= 0.583**). The increasing of the percent organic matter contents of the soils increased the exchangeable sodium (r= 0.432*), available phosphorus (r= 0.450*) and nickel extraction (r= 0.434*). Whereas the rising of soil pH decreased the extraction of the available phosphorus and the rising of organic matter contents decreased the copper extraction (r= -0.529**). The lead extraction increased by the exchangeable calcium (r= 0.506**). There was a significant positive correlation between the exchangeable magnesium and exchangeable sodium (r= 0.545*).  The results of this study in agreement with the others findings such as Agboola and Corey (1973), found significantly positive correlations between the soil pH and exchangeable calcium and between the soil organic matter and available phosphorus. The decrease effect of rising of soil pH on the available phosphorus has been a well known effect of soil reaction on soil phosphorus. The relationships between the heavy metal contents of the leaves and the soil variables: The linear correlation coefficient analysis results between the heavy metal contents of the wheat leaves and the soil variables given in the Table 5. As shown in the Table 5, the heavy metal contents of the leaves were not effected by the soil reaction. The total iron contents of the leaves decreased significantly by the increasing levels of the organic matter (r= -0.363*), exchangeable calcium (r= 0.483*) and extractable lead (r= -0.410*). Although the extractable lead level of the soils were low it decreased significantly the iron contents of the leaves. The decrease effect of the rising exchangeable calcium on the iron uptake of the plants or reducing of iron function in the plant metabolism was a well known effect of the soil calcium, calcium carbonate, carbonate or bicarbonate. This event occurred in this study because of the high exchangeable calcium contents of the soils. The arid climate conditions of the area was caused of the accumulation of the basic cation such as calcium. Elinç (1988), found a significantly negative relation between the iron contents of plant and soil organic matter. The total manganese levels of the leaves decreased significantly by the increasing calcium carbonate (r= -0.469*). Agboola and Corey (1973), found a significantly negative relation between the manganese contents of plant and soil calcium. The total zinc contents of the leaves decreased significantly by the increasing of organic matter (r= -0.370*) and the increasing of available phosphorus (r= -0.418*) levels in the soils. Whereas there were synergetic effects of the extractable iron and manganese on the zinc contents of the leaves. It is well known that phosphorus has an antagonistic effect on the zinc uptake or zinc contents of plants, which effect of the phosphorus occurred in this study. It is to be recommended that to use of the phosphorus fertilizer has to be taken under control and to avoid excess usage of the phosphorus fertilizer. Elinç (1987), found a significantly negative relation between the soil organic matter and zinc contents of plant. The total copper contents of the leaves decreased significantly by the increasing calcium carbonate (r= -0.426*) and exchangeable calcium (r= 0.538*). Whereas there was a synergetic effect of the exchangeable magnesium on the copper contents of the leaves. The total nickel contents of the leaves decreased significantly by the increasing soil zinc (r= -0.409*). The antagonist effects of the divalent cations is a well known relations. That antagonistic effect of the soil zinc on the nickel contents of the leaves gained importance considering the slightly high level nickel contents of the leaves. It is to be said zinc fertilization would be recommended on the area in the point of view to increase zinc contents and decreased the nickel contents of the crops. In this way the quality and the quantity of the crop yields are to be increased.  CONCLUSIONS The results obtained indicated that the zinc contents of the wheat leaves decreased significantly by the increasing available phosphorus level of the soils. Although the available zinc levels of the soils were low, the total nickel contents of the leaves decreased by the increasing zinc level of the soils. Considering the results of the study it is to be suggested that it will to be useful to avoid the usage of excess level of phosphorous fertilizer to control the zinc deficiency and the nickel accumulation in the plant tissue. In this way the quality and the quantity of the crop yields are to be increased in the point of view human and animals nourishment and public health. REFERENCES Agboola A.A., and Corey R.B. (1973) The relationship between soil pH, organic matter, available phosphorus, exchangeable potassium, calcium, and nine elements in the maize tissue. Soil Sci., No: 5, Vol: 115, p. 367-375. Ascher C. J. (1991) Beneficial elements, functional nutrients , and possible new essential elements. Chapter, 18, p. 713. In J.J. Mortvedt, F.R. Cox, L.M. Shuman and R.M. Welch, eds. Micronutrients in Agriculture, SSSP Book Series: 4, Second Edition, Madison, Wisconsin, USA. Elinç F. (1987) Meriç Havzası Vertisol ve Kireçsiz Kahverengi Topraklarda II. Yarayışlı Zn, Fe, Mn, Cu ve B düzeyleri ile bazı toprak özellikleri arasındaki ilişkiler, I. Trakya Toprak ve Gübre Sempozyumu, Trakya Üniversitesi, Tekirdağ, say. 253-256. Hızalan E., ve Ünal H. (1966) Topraklarda Önemli Kimyasal Analizler. A.Ü. Ziraat Fakültesi Yayınları, 278, Yardımcı Ders Kitabı, 97, A.Ü. Basımevi, Ankara. Jackson M. L. (1962) Soil Chemical Analysis. Printice-Hall, Inc., 183. Jones J.B.Jr., Wolf B., and Mills H.A. (1991) Plant Analysis Handbook. I. Methods of Plant Analysis and Interpretation. Micro-Macro Publishing Inc., USA. Kacar B. (1972) Bitki ve Toprağın Kimyasal Analizleri: II. Bitki Analizleri. A:ü: Ziraat Fakültesi Yayınları, 453, Uygulama Klavuzu, 155. A.Ü. Basımevi, Ankara. Lindsay W. L., and Norvell W.A. (1969) Development of DTPA micronutrient soil test. Agron. Abstr. 84. Macy P. (1939) The quantitative mineral nutrient requirement of plants. Plant Physiol. 11:749-764. Olsen S.R., Cole V., Watanabe F.S., and Dean L.A. (1954) Estimation of available phosphorus in soils by extraction with sodium bicarbonate. U.S. Dept. of Agr. Cir. 939, Washington, D.C. Peck T.R., Walker W.M., and Borne L.V. (1969) Relationship between corn (Zea mays L.) yield and leaf levels of ten elements. Agron. J. 61:299-301. Risser J.A., and Becker D.E. (1991) Testing soils for toxic metals. Chapter, 11, p. 284. In R.L. Westerman, J.V. Baird, N.W. Christensen, P.E. Fixen, and D.A. Whitney, eds. Soil Testing and Plant Analysis, SSSP Book Series: 3, Third Edition, Madison, Wisconsin, USA. Sims J.T. (1986) Soil pH effects on the distribution and plant availability of manganese, copper, and zinc. Soil Sci. Soc. Am. J. Vol. 50, No. 2, p. 367-373. Shear C.B., Crane H.L., and Myers A.T. (1948) Nutrient element balance. Application of the concept to the interpretation of foliar analysis. Proc. Am. Soc. Hort. Sci. 5:319-326. Steel R.G.D., and Torrie J.H. (1960) Principles and Procedures of Statistics with Special References to The Biological Sciences. McGraw-Hill Book Company, Inc. New York. Tyner E.H. (1947) The relationship of corn yield to leaf phosphorus, and potassium content. Soil Sci. Soc. Am. Proc. 11:317-323. |