DYNAMICS OF MAGNESIUM, COPPER AND ZINC FROM SOIL TO FORAGES GROWN IN SEMIARID AREA IN SARGODHA, PAKIST

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1 Legume Res., 35 (4) : , 2012 AGRICULTURAL RESEARCH COMMUNICATION CENTRE ccjournals.com / indianjournals.com nals.com DYNAMICS OF MAGNESIUM, COPPER AND ZINC FROM SOIL TO FORAGES GROWN IN SEMIARID AREA IN SARGODHA, PAKIST AKISTAN AN Kafeel Ahmad, Zafar Iqbal Khan, Muneeba Shaheen, Alireza Seidavi 2 Department of Biological Sciences, University of Sargodha, Sargodha, Pakistan Received: Accepted: ABSTRACT This investigation was carried out to determine the concentrations of certain essential elements (Zn, Mg and Cu) in soil and forages from two different ent sites in the pasture in Sargodha, Pakistan during two consecutive seasons of the year.. The purpose of this study was to evaluate the concentrations of these essential elements (Zn, Mg and Cu) in soil and forages in relation to the needs of livestock grazing therein.the results showed that mean soil and forage values of these elements generally decreased from summer to winter seasons at both sites of the pastureland. Mean forage elements were found to be lower than the requirements of livestock consuming these forages in the studied pastureland. The Cu and Zn concentrations in soil were found to be closely related to required level for forage from the soil, but Mg was higher than the required level, indicating no need of soil amendment for enhancing the level of this element in soil for forage crops. Based on these findings, it was concluded the pasture soil should be amended with Cu and Zn containing fertilizers and the ruminants feeding on those forage species should also be continually supplemented with specifically tailored mineral mixture containing these elements to avoid diseases caused by deficiency of these mineral elements. Key words: Magnesium, Copper, Zinc, Soil, Forage. INTRODUCTION industrialization and urbanization. (Al-yemeni et al., Suitable amount of minerals is necessary for 2011a; Ahmad et al., 2008; McGrath et al., 1997). the growth, development and high yield of animals In grazing livestock, low level of Mg and high level of grazing in pastures (Underwood, 1981; Khan et al., K produced hypomagnesaemia disorders because of 2006, 2007a, b). Although, food containing high less amount of Mg assimilation in gastrointestinal amount of minerals does not make sure the cavity (Ram et al., 1998; Schonewille et al., 1999). availability to grazing livestock (Littledike and Goff, In spite all of these, for metabolic activities proper 1987). Grazing animals acquire minerals from the amount of minerals were necessary for ruminant and forages in normal browsing situations. On the other their uptake of minerals could be determined by the hand insufficient amount of minerals leads to less yield of animals (Minson et al., 1976; Khan et al., absorption of minerals in forages (McDowell, 2003; 2005a, b; Khan et al., 2007). The information Yusuf et al., 2003).To increase the animal productivity regarding the concentration of minerals in the animal magnesium supplementation was essential (Khan et body or blood plasma is commonly taken as a al., 2008). In Punjab mineral supplementation diagnostic tool to evaluate many ailments. Unusual can improve the production of livestock. In forms of feeding behavior have seen in goats and sheep with dietary allusion. Goats have a preference different regions of the world,very lower of browsing and sheep favor grazing. Different plant concentration of micro and trace minerals in species have different concentration of minerals due soil,forage and livestock have very intimate to marked seasonal variation (Tolsma et al., 1987; association (Grace et al., 1996; McDowell and Ben-Shahar and Coe, 1992; Khan, 2003; Khan et al., 2004). Therefore variation in seasons and feeding Arthigton, 2005). In Pakistan, investigations sites may have influence on the concentration of regarding mineral responsive conditions among minerals. Different type of disorder in animal have grazing ruminants are available but related survey been related to mineral imbalances in soil due to rapid from different agro-climatic zones are scanty. In this Corresponding author s E mail:zikhan11@gmail.com, 2 Department of Animal Science, Rasht Branch, Islamic Azad University, Rasht, Iran

2 Vol. 35, No. 4, investigation, difference of minerals digesting material on hot plate. When fumes concentration in soil and different forages were stop to evaporate, removed the beaker and investigated to check their effect on the livestock added 2ml of H 2 O 2. Again heat and the process grazing therein in relation to their requirements. were continued until the material became Experimental Procedure: The current investigation was carried out in the suburb of colourless. Then digested material was removed and after filtration made the volume up to 50ml Sargodha, Pakistan to evaluate the soil and with double distilled water, labeled and kept in forage magesium zinc and copper. Soil and a plastic bottle. Similarly forage samples were forage samples were collected during two wet digested for mineral determination.soil and seasons, each sampling was carried out three forage minerals were determined using the times in each season. The lowest and highest atomic absorption spectrophotometry. temperature during the investigation range from 7 0 C to 25 0 C respectively, with mean precipitation during this period was 200 mm. Statistical Analysis The data obtained was statistically Four species of wild forage plants were analyzed through a soft ware called SPSS.12 and selected for minerals investigation.the forage statistical significance was tested at 0.05, 0.01 species were those which mostly spread in that and levels of probability as suggested by pasture and the main source of water for Steel and Torrie (1986). irrigation for these forages was rain in this area RESULTS AND DISCUSSION of study. Magnesium (Mg) Preparation of samples for analytical work After samples were collected, soil was dried in an incubator at 60 o C for one week. 1g of soil sample was digested with 4ml conc. HNO 3 and 8ml H 2 O 2 in a beaker by placing the Soil: There was noticeable sampling periods consequence (P<0.001) on Mg concentration of soil (Table 1a).Soil Mg concentration speckled considerably with inconsistent trends in decrease or increase during different sampling times. The TABLE 1a: Analysis of variance for Mg concentrations in soil and forage at different sampling intervals. Source of variation (SOV) Degree of freedom Mean Squares (df) Soil Forages Site 1 Site 2 Species 1 Species 2 Species 3 Species 4 Sampling period(summer) *** *** 28.6*** 3.66ns 10.84ns 0.107ns Error Sampling period(winter) *** *** 9.436* 0.123ns ns 0.002ns Error , Data is expressed as mean squares significant at (P<0.05-P<0.001), vs. control where *=0.05, **=0.01, ***= ns= non significant Species 1= Dactyloctenium aegyptium Species 2= Calotropis procera Species 3= Parthenium hysterophorus Species 4= Eragrostis pilosa TABLE 1b: Variation of Mg level in summer and winter soil at two different sites (Site 1= contaminated site, Site 2=uncontaminated soil) Soil Sample period Site 1 Site 2 Oct ± ±0.188 Nov ± ±0.217 Dec ± ±0.055 Jan ± ±0.303 Feb ± ±0.153 Mar ± ±0.034s lowest level of soil Mg were observed in January at site 1 where as highest level of Mg concentration was found in November at site 1. Regular decrease was observed from 1 st period to last one period. The concentration of Mg ranged from mg/kg during all sampling times. Mean Mg ranged from mg/kg at site 1 while mg/kg at site 2.

3 296 LEGUME RESEARCH FIG 1a: Magnesium level fluctuations in soil at different sampling periods TABLE 2a: Analysis of variance for Cu concentrations in soil and forage at different sampling intervals. Source of variation (SOV) Degree of freedom Mean Squares (df) Soil Forages Site 1 Site 2 Species 1 Species 2 Species 3 Species 4 Sampling period(summer) ns 0.466* 0.781ns 2.33*** 0.267* 0.627ns Error Sampling period(winter) *** 0.141*** 0.595ns 0.123* 0.083* 0.000ns Error Data is expressed as mean squares significant at (P<0.05-P<0.001), vs. control where *=0.05, **=0.01, ***= ns=non significant Species 1= Dactyloctenium aegyptium Species 2= Calotropis procera Species 3= Parthenium hysterophorus Species 4= Eragrostis pilosa TABLE 2b: Variation of Cu level in summer and winter soil at two different sites (Site 1= contaminated site, Site 2=uncontaminated soil) Soil Sample period Site 1 Site 2 Oct ± ±0.043 Nov ± ±0.098 Dec ± ±0.136 Jan ± ±0.083 Feb ± ±0.007 Mar ± ±0.005 In the current investigation the soil Mg level was parallel to those standards reported previously by different researchers (Cuesta et al., 1993; Tiffany et al., 2001). All the soil samples of summer season analyzed were above the critical level of 30 mg/kg for Mg concentration (Rhue and Kidder, 1983). It was appropriate for the necessities of grazing ruminants. Likewise our values were in contrast to the values as reported by Hanlon et al. (1990). The concentration of Mg was below in winter season so in winter there was need of fertilizers application. They need no fertilizers for pastures imminent. Forage Analysis of variance shows that Mg concentration was affected (P<0.05, P<0.001)) significantly by the sampling periods of only one forage while non-significantly affected on all other

4 Vol. 35, No. 4, FIG 1b: Magnesium level fluctuations in forage at different sampling periods FIG 2a: Copper level fluctuations in soil at different sampling periods

5 298 LEGUME RESEARCH FIG 2b: Copper level fluctuations in forage at different sampling periods. TABLE 3a: Analysis of variance for Zn concentrations in soil and forage at different sampling intervals. Source of variation (SOV) Degree of freedom Mean Squares (df) Soil Forages Site 1 Site 2 Species 1 Species 2 Species 3 Species 4 Sampling period(summer) *** 0.573*** 10.12ns 7.945ns 16.66ns 6.92ns Error Sampling period(winter) *** 0.001ns 1.172ns 12.50ns 0.055ns 0.232ns Error Data is expressed as mean squares significant at (P<0.05-P<0.001), vs. control where *=0.05, **=0.01, ***= Species 1= Dactyloctenium aegyptium Species 2= Calotropis procera Species 3= Parthenium hysterophorus Species 4= Eragrostis pilosa TABLE 3b: Variation of Zn level in summer and winter soil at two different sites (Site 1= contaminated site, Site 2=uncontaminated soil) Soil Sample period Site 1 Site 2 Oct ± ±0.156 Nov ± ±0.068 Dec ± ±0.123 Jan ± ±0.005 Feb ± ±0.014 Mar ± ±0.020 sampling periods (Table 1a). The mean values ranged from mg/kg in Dactyloctenium aegyptium in summer and mg/kg in winter, mg/ kg in Calotropis procera in summer and mg/kg, mg/kg in Parthenium hysterophorus in summer and mg/kg in winter, mg/kg in Eragrostis pilosa in summer and mg/kg in winter. Lowest Mg concentration was found during winter and highest Mg concentration was observed in summer. Our values were below the critical limit reported by McDowell et al., (1984) as 0.20%. The values of present study is higher than the values reported by Prabowo et al. (1990) and below from the values already established by Fujihara et al. (1992) and Khan et al. (2009). The present study showed that the level of Mg were in the safe limit. Copper (Cu) Soil: Soil Cu concentration data was affected significantly (P<0.05) by sampling periods at site 1

6 Vol. 35, No. 4, FIG 3a: Zinc level fluctuations in soil at different sampling periods but more significant (P<0.001) at site 2 (Table 2a). The value of soil Cu content ranged from 0.21 to 3.47 mg/kg at site 1 while 0.17 to 3.79 at site 2. The concentration of Cu in soil decreased continuously during summer to winter but a sudden increase in March at site 1 (Fig 2a). The standards found all through at hand study were elevated than the critical value of 0.3 mg/kg by (Rhue and kidder, 1983; McDowell, 1984; Rojas, 1993). And also lower than the values already observed by Jerez et al. (1984) in Florida. The values were similar to the critical level studied by Khan et al. (2008). Forage: The analysis of variance for Cu concentration in case of forage indicated significant effect (P< 0.05) during summer but significant (P<0.001) during winter (Table 2a). The mean values ranged from mg/kg in Dactyloctenium aegyptium in summer and mg/kg in winter, mg/kg in Calotropis procera in summer and mg/kg, mg/kg in Parthenium hysterophorus in summer and mg/kg in winter, mg/kg in Eragrostis pilosa in summer and mg/kg in winter. The values were lower than critical value suggested as 8 mg/kg and 10 mg/kg by (Merkel et al., 1990; Anon, 1996, 2006; Rhue and kidder, 1983). The variation in Cu forage concentration from 1 st to last sampling period illustrates inconsistent pattern. Low concentration of Cu in forages grazed by ruminants in the study area was indicative of quantity and availability of this element in soil (Reid and Horvath, 1980). Data seemed to demonstrate that the Cu concentration of forage species were affected by the soil, where they were grown. This finding corroborate with findings of Norton and Poppi (1995) that they reported trace mineral values of forages were more indicative of the soil types than any other factor. High Mo (molybdenum) intake depressed Cu availability and may produce physiological changes in ruminants (Underwood and Suttle, 1999). The values was almost similar to the values observed by (Dey et al., 1996) when he was working on the plants under polluted area of industry in India. He examined mean concentrations of metals like lead, copper and cadmium as 46, and mg/kg respectively. Zinc (Zn) Soil: Analysis of variance for soil exhibited significant effect (P<0.001) of sampling periods (Table 3a). Soil Zn amounts were different at all sampling periods. This variation was mainly the result of leeching of Zn with water. Total content of Zn metal in soil was determined by wet digestion of concentrated acid

7 300 LEGUME RESEARCH FIG 3b: Zinc level fluctuations in forage at different sampling periods and measured on Atomic Absorption Spectrophotometer. Mean content in soil ranged from at site 1 and from mg/kg at site 2. The highest soil Zn was found at site 2 in summer season. Critical level for Zn is 0.5 mg/kg by (Sanchez, 1976; Anon, 1980). The values of winter season were similar to this investigation but in summer slightly above values were found. Zn level in summer was similar to values given by Rhue and Kidder, So there is no need of any fertilizer for Zn level balance. According to Dabkowsca Naskret et al. (2004), low level of available Zn because in neutral soil is due to the form of Zn bound to Iron oxide (FeO) making it unavailable to plants, but in our study sufficient amount of Zn was found than the normal requirement for plant growth. Forage: The forage Zn concentration rendered non significant effect during different sampling intervals (Table 3a). Zn content in forage was highest during summer season rather than winter. However, zinc showed inconsistent trend in increase or decrease at different sampling times. Its values varied from mg/kg in Dactyloctenium aegyptium, mg/kg in Calotropis procera, mg/kg in Parthenium hysterophorus and mg/kg in Eragrostis pilosa in winter season. All the forage values were deficient than the critical level established for ruminants by NRC (1996). Zn content of forage was fairly lower than the standard. Similar forage Zn concentration in forage had been reported by Fujihara et al. (1992) in China and Espinoza et al. (1991) in Florida. Its values varied from mg/kg in Dactyloctenium aegyptium, mg/kg in Calotropis procera, mg/kg in Parthenium hysterophorus and mg/kg in Eragrostis pilosa in winter season. Zn values were lower than reported by (McDowell et al., 1982). These values for forage Zn were lower than those had already being reported by (Tiffany et al., 2001) in Florida. All the forage values were deficient than the critical level established for ruminants by NRC (1996). Zn content of forage was fairly lower than the standard. Similar forage Zn concentration in forage had been reported by Fujihara et al. (1992) in China and Espinoza et al. (1991) in Florida. Zn concentration may be occasionally as high as 30 ppm. But this can decline rapidly as plant matures (McDowell et al., 1982). Contrary to present findings various workers has reported higher values of Zn in forages (Khan et al., 2007; Prabowo et al., 1990). Zn concentration was comparatively less in broad leaved plants as compared to grasses (Malik et al., 2010).

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