Effect of organic and inorganic nutrient sources on available sulphur, aryl sulfatase activity and yield of ashwagandha

An Asian Journal of Soil Science Volume 8 Issue 1 June, 2013 Research Article Effect of organic and inorganic nutrient sources on available sulphur, aryl sulfatase activity and yield of ashwagandha MEMBERS OF RESEARCH FORUM : Corresponding author : B. VAJANTHA, Department of Soil Science, Agricultural Research Station, Perumallapalle, TIRUPATHI (A.P.) INDIA Co-authors : M. UMADEVI, M.C. PATNAIK AND M. RAJKUMAR, Department of Soil Science and Agricultural Chemistry, College of Agriculture, Rajendranagar (ANGRAU) HYDERABAD (A.P.) INDIA Received : 15.12.2012; Revised : 08.02.2013; Accepted : 10.03.2013 Summary The field experiments were conducted to study the effect of organic and inorganic fertilisers on available S, aryl sulfatase activity and root yield of Ashwagandha and it revealed that combined effect of organic and inorganic sources of nutrients proved better than effect of their individual use. Among the various combinations studied performanance of 150% RDF+castor cake @2.5 t ha -1 + bio fertilisers recorded the highest available S (13.62 and 10.73 kg ha -1 at harvest in Rabi 2007-08 and Kharif 2008, respectively)), aryl sulfatase activity (51.21 and 45.12 µg of p-nitro phenol released g -1 soil h -1 ) and dry root yield (348 and 333 kg ha -1 at harvest in Rabi 2007-08 and Kharif 2008, respectively). Key words : Ashwagandha, Castor cake, Vermicompost, Panchagavya, Available S, Enzyme activity, Dry root yield How to cite this article : Vajantha, B., Umadevi, M., Patnaik, M.C. and Rajkumar, M. (2013). Effect of organic and inorganic nutrient sources on available sulphur, aryl sulfatase activity and yield of ashwagandha. Asian J. Soil Sci., 8(1):. Introduction India is one of the 12 mega biodiversity centres and could be termed as botanical garden of the world with a wealth of 8000 species of medicinal plants. Ashwagandha is an important medicinal plant grown in different states of India. The roots of Ashwagandha contains several alkaloids namely withasomnine, steroidal, withaferin A, withaferin B and withanolides.withaferin is a bacteriostatic and antitumerous agent. Organic are main source of nutrients and they have considerable effect on soil enzymes. The enzyme activity is considered as an index of microbial activity. Enzymes in soil are biologically significant as they participate in the transformation, cycling of mineral nutrients and influence their availability to plants. The activity of soil enzymes are influenced by the nature, age of crop, addition of fertilisers and. The present investigation was undertaken to asses the effect of combined use of organic and inorganic nutrient sources on available S, aryl sulfatase activity and dry root yield of ashwagandha. Resource and Research Methods Two field experiments were conducted to study the effect of organic and inorganic sources of nutrients on available sulphur, aryl sulfatase activity and dry root yield of Ashwagandha at College of Agriculture, Rajendranagar, ANGRAU at Hyderabad on a sandy clay loam soil during Rabi 2007-08 (I year) and Kharif 2008 (II year). A composite soil sample was collected in both the years from the experimental site (0-20 cm) before the experiment and analysed. The experimental site during both the years was sandy clay loam in texture, slightly alkaline in reaction (7.60 and 7.54) and non-saline (0.16 and 0.18 ds m -1 ) in nature. It was low in organic carbon (0.40 and 0.40 per cent) and low in available nitrogen (203 and 200 kg ha -1 ) and medium in available phosphorus (17.08 and 17.12 kg ha -1 ) and high in available potassium (287 and 263 kg ha -1 ). The chemical composition of castor cake, vermicompost, Panchagavya was presented in Table A. The experiment was laid out in split plot design with three replications. There were totally 16 treatment combinations consisting of 4 main and 4 sub treatments. The main treatments were levels of NPK viz., 0%, 50%, 100% and 150% NPK and HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE

Table A : Chemacal composition of castor cake, vermin-compost and Panchagavya Nutrient composition Costor cake Vermi-compost Panchagavya N (%) 5 1.5 0.44 P (%) 2.2 1 0.41 K (%) 2 0.5 1.02 S (mg kg-1) 23 33 30 Zn (mg kg-1) 76 64 28 Fe (mg kg-1) 92 52 87 Mn (mg kg-1) 45 39 20 Cu (mg kg-1) 40 57 17 Yeast (CFU/ml) - - 38x10 4 Actinomycetes (CFU/ml) - - 4x10 2 Lactic acid bacteria (CFU/ml) - - 26x10 6 the sub treatments were no, castor cake@ 2.5 t ha - 1 +, vermincompost@ 1 t ha -1 +, Panchagavya @5% at 30,, 60 and 90 days after sowing+. Preparation of Panchagavya : Panchagavya is an organic product prepared by mixing five products obtained from cow viz., cow dung (5 kg), cow urine (3 litres), cow milk (2 litres), cow curd (2 litres) and cow ghee (1 litre). In addition to the above products, sugarcane juice (3 litres), tender coconut water (3 litres) and riped banana (1 kg) was also added to get 20 litres of Panchagavya stock solution. The mixture is placed in a wide mouthed mud pot and kept under shade. The contents were stirred twice a day for about 20 minutes, both in the morning and in the evening to facilitate aerobic microbial activity. About 10 days after fermentation, it was used for spraying (Natarajan, 2003). Recommended dose of NPK (60-50-40 kg ha -1 ) were applied through urea, single super phosphate and muriate of potash, respectively. Organic were applied one week before sowing in the field. Representative soil samples were collected from each plot at flowering and harvest in both the years for chemical analysis. The soil samples were analysed for nutrient status by adopting the standard procedures as outlined by Chesnin and Yien (1951). Aryl sulfatase was analysed as per the procedure given by Tabatabai and Bremner (1970). The dry root yield was recorded at harvest. Research Findings and Discussion The results of the present study as well as relevant discussions have been presented under following sub heads: Available S : The available S increased significantly with application of inorganic fertilisers, organic and bio fertilisers. The available S increased with graded levels of NPK. It was conformed with the findings of Kumar et al.(2002). The treatment castor cake + showed the highest available S followed by vermicompost @ 1 t ha -1 + and Panchagavya @ 5% + at both the stges in both years. Conjunctive application of 150% RDF+ castor cake + recorded the highest available S ( 13.62 and 10.73 kg ha -1 at harvest during Rabi 2007-08 and Kharif 2008, respectively) at both stages during both the years (Table 1 and 2). In general the available S in soil was decreased (0.16 to 0.84 during Rabi 2007-08 and 0.16-1.35 kg ha -1 during Kharif 2008) at harvest when compared with flowering. Except control all the treatments resulted in build up of available S when compared to the initial available S. In Rabi 2007-08 at harvest, the % increase in soil available S over control was 3.38, 6.41 and 7.49% with 50%, 100% and 150% of NPK, respectively. Application of 100% NPK increased the available soil S over 50% NPK by 2.93%, while application of 150% NPK increased the available soil S over 100% by 0.97 %. Application of Panchagavya+, vermicompost + and castor cake + recorded 7.17, 22.09 and 25.38%, respectively increase over no. The control plot and 50% NPK showed depletion (- 4.53% and -2.45%, respectively) of available S when compared with initial available S (10.60 kg ha -1 ). However, all other plots resulted build up of available S. The highest build up was noticed with 150% NPK + castor cake + (28.49%). The increased application of SSP resulted in significantly higher available S as it is also indirect source of sulphur (Kumar and Yadav, 2005). During Kharif 2008 at harvest, the soil available S was increased 2.61, 4.31 and 4.91% with 50% NPK, 100% NPK and 150% NPK, respectively over no fertilisers. The 100% NPK noticed 0.57% increased over 50% NPK and application of 150% NPK increased 1.66% soil available S than 100% NPK. The % increased with castor cake +, vermicompost + and Panchagavya+ was 6.91, 5.48 and 4.57%, respectively over no. Aryl sulfatase activity : Aryl sulfatase is the enzyme that catalyses the hydrolysis HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 20 Asian J. Soil Sci., (June, 2013) 8 (1) :

EFFECT OF ORGANIC & INORGANIC NUTRIENT SOURCES ON AVAILABLE SULPHUR, ARYL SULFATASE ACTIVITY & YIELD OF ASHWAGANDHA Table 1: Effect of inorganic fertilisers, organic, Panchagvya and bio fertilisers on soil available sulphur (kg ha -1 ) at flowering and harvest of shwagandha during Rabi 2007-08 (I year) castor cake vermicomp ost @ 1 t ha - 1 + Panchakavya @ 5% foliar spray + castor cake vermicompost @ 1 t ha -1 + Panchakavya spray + M 1 10.73 13.16 12.84 11.06 11.95 10.12 12.84 12.42 10.78 11.54 fertilizers (1.23) (24.15) (21.13) (4.34) (12.74) (-4.53) (21.13) (17.17) (1.70) (8.87) M 2 11.15 13.88 13.17 11.50 12.43 10.34 13.12 12.90 11.34 11.93 50% NPK (5.19) (30.94) (24.25) (8.49) (17.26) (-2.45) (23.77) (21.70) (6.98) (12.55) M 3 11.62 14.16 13.42 12.08 12.80 10.84 13.50 13.18 11.62 12.28 100% NPK** (9.62) (33.58) (26.60) (13.96) (20.75) (2.26) (27.36) (24.34) (9.62) (15.85) M 4 11.90 14.33 13.50 12.26 13.00 11.08 13.62 13.23 11.70 12.40 150% NPK (12.26) (35.19) (27.36) (15.66) (22.64) (4.53) (28.49) (24.81) (10.38) (16.98) 11.35 13.88 13.23 11.73 10.59 13.27 12.93 11.35 (7.08) (30.94) (24.81) (10.66) (-0.09) (25.19) (21.98) (7.08) 0.48 0.17 0.40 0.16 0.34 0.11 0.37 0.14 at same or different levels of sub 0.78 0.25 0.71 0.27 Values in the paranthasis indicate the per cent build up or depletion over initial available potassium, Initial available sulphur --- 10.60 kg ha -1, * - Bio -1 Table 2: Effect of inorganic fertilizers, organic and Panchagavya on soil available sulphur (kg ha -1 ) at flowering and harvest of Ashwagandha during Kharif 2008 (II year) S 1 S 3 S 4 S 1 S 3 S 4 Castor cake Vermicomp Panchagavya Castor cake Vermicompost ost @ 1 t @ 1 t ha -1 + ha -1 + spray + Panchagavya @ 5% foliar spray + M 1 10.02 11.32 11.04 10.26 10.66 9.35 10.92 10.18 10.08 9.96 fertilizers (-0.99) (11.86) (9.09) (1.38) (5.34) (-7.61) (7.91) (0.59) (-0.40) (-1.58) M 2 10.67 11.64 11.52 10.97 11.20 9.95 10.44 10.30 10.22 10.22 50% NPK (5.43) (15.02) (13.83) (8.40) (10.67) (-1.68) (3.16) (1.78) (0.99) (0.99) M 3 10.18 11.92 11.60 11.32 11.20 10.02 10.67 10.48 10.40 10.39 100% NPK** (0.59) (17.79) (14.62) (11.86) (10.67) (-0.99) (5.43) (3.56) (2.77) (2.67) M 4 10.25 12.08 11.78 11.38 11.37 10.08 10.73 10.55 10.46 10.39 150% NPK (1.28) (19.37) (16.40) (12.45) (12.35) (-0.40) (6.03) (4.25) (3.36) (2.67) 10.13 11.74 11.48 10.98 9.84 10.53 10.38 10.29 (0.10) (16.01) (13.44) (8.50) (-2.77) (4.05) (2.57) (1.68) 0.24 0.09 0.18 0.05 0.22 0.08 0.08 0.03 at same or different levels of sub 0.42 0.15 0.19 0.07 Values in the paranthasis indicate the per cent build up or depletion over initial available potassium, Initial available sulphur --- 10.12 kg ha -1 * -, Bio fertilizers (Azospirillum + Phosphorous Solubilizing Bacteria), 100% NPK** = 60-50 - 40 kg NPK ha -1 HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 21 Asian J. Soil Sci., (June, 2013) 8 (1) :

of organic sulphate esters. Aryl sulfatase is believed to be partly responsible for S cycling in soils as it participate in mineralisation of organic S to SO 4 2- for plant uptake. The data on aryl sulfatase activity in soil at flowering and harvest during Rabi 2007 2008 and Kharif 2008 was presented in Table 2 and 5, respectively. In both the years it was decreased at harvest Table 3: Effect of inorganic fertilizers, organic, Panchagavya and bio fertilizers on aryl sulfatase activity (µg of p-nitrophenol released g -1 soil h -1 ) at flowering and harvest during Rabi 2007-08 (I year) Castor cake @ 2.5 t ha -1 + * Vermicompost @ 1 t ha -1 + Panchagavya @ 5% foliar spray + Castor cake @ 2.5 t ha -1 + * Vermicomp ost @ 1 t ha -1 + Panchagavya spray + M 1 52.20 58.55 57.46 55.44 55.91 7.42 41.87 39.02 38.80 39.06 fertilizers (26.89) (29.42) (27.01) (22.55) (23.59) (-19.23) (-7.44) (-13.74) (-14.23) (-13.66) M 2 55.16 64.82 60.00 58.35 59.58 38.64 44.98 43.04 42.14 42.20 50% NPK (21.93) (43.28) (32.63) (28.98) (31.70) (-14.58) (-0.57) (-4.86) (-6.85) (-6.71) M 3 57.66 69.78 66.34 63.08 64.22 41.22 48.23 46.43 42.65 44.63 100% NPK** (27.45) (54.24) (46.64) (39.43) (-2.25) (-8.88) (6.60) (2.63) (-.72) (-1.35) M 4 60.22 75.34 70.12 66.45 68.03 44.32 51.21 49.24 46.65 47.54 150% NPK (33.11) (66.53) (55.00) (46.88) (50.38) (-2.03) (13.39) (8.84) (3.12) (5.08) 56.31 67.12 63.48 60.83 39.87 46.57 44.43 42.56 (24.47) (48.36) (63.48) (60.83) (-11.87) (2.94) (-1.79) (-5.92) 1.38 0.38 2.08 0.97 1.30 0.36 1.96 0.85 at same or djfferent levels of sub 2.56 0.78 3.87 1.67 Initial aryl sulfatase activity ---- 45.24 µg of p-nitrophenol released g -1 soil h -1, Values in the parenthesis indicates the % increase or decrease over intial aryl sulfatase activity, * - Bio fertilizers (Azospirillum + Phosphorus Solubilizing Bacteria), 100% NPK** = 60-50 - 40 kg NPK ha -1 Table 4: Effect of inorganic fertilizers, organic, Panchagavya and bio fertilizers on aryl sulfatase activity (µg of p-nitrophenol released g -1 soil h -1 ) at flowering and harvest during Kharif 2008 (II year) Castor cake Vermicompost @ 1 t ha -1 + Panchagavya spray + Castor cake HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 22 Asian J. Soil Sci., (June, 2013) 8 (1) : Vermicompost @ 1 t ha -1 + Panchagavya spray + M 1 48.02 55.08 53.87 52.34 52.33 34.12 38.68 36.44 35.32 36.14 fertilizers (4.58) (19.95) (17.31) (13.98) (13.96) (-25.67) (-15.76) (-20.63) (-23.08) (-21.29) M 2 50.74 61.09 55.2 53.682 55.18 37.13 40.78 40.19 38.36 39.12 50% NPK (10.51) (33.04) (20.21) (16.90) (20.17) (-19.14) (-11.19) (-12.45) (-16.46) (-14.80) M 3 53.04 64.19 61.03 57.16 58.86 38.49 42.56 40.92 39.83 40.45 100% NPK** (15.52) (39.80) (32.91) (24.48) (28.18) (-16.15) (-7.31) (-10.88) (-13.25) (-11.91) M 4 54.8 69.31 65.5 59.94 62.39 41.39 47.83 43.54 42.09 43.42 150% NPK (19.34) (50.94) (42.64) (30.53) (35.87) (-9.85) (4.15) (-5.18) (-8.34) (-5.44) 51.65 62.42 58.9 55.78 37.49 42.46 40.28 38.9 (12.48) (35.93) (28.27) (21.47) (-18.35) (-7.53) (-12.28) (-15.28) 1.41 0.56 1.08 0.40 1,26 0.41 1.02 0.36 at same or djfferent levels of sub 2.48 0.92 N.S 0.72 Initial aryl sulfatase activity --- 45.92 µg of p-nitrophenol released g -1 soil h -1,Values in the parenthesis indicates the % increase or decrease over intial aryl sulfatase activity, * - Bio fertilizers (Azospirillum + Phosphorus Solubilizing Bacteria), 100% NPK** = 60-50 - 40 kg NPK ha -1

EFFECT OF ORGANIC & INORGANIC NUTRIENT SOURCES ON AVAILABLE SULFUR, ARYL SULFATASE ACTIVITY & YIELD OF ASHWAGANDHA than flowering. The aryl sulfatase activity of soil at flowering differed significantly with fertiliser levels,, Panchagavya and as well as with their interaction except at harvest in Kharif 2008. In both the years, in between fertilizer levels significantly the highest aryl sulfatase activity was recorded with 150% NPK followed by 100% NPK and 50% NPK with significant disparity between any two of four levels while the lowest was noticed with no fertilisers except at harvest in Rabi 2007-2008 where application of 100% NPK was at par with 50%NPK. Among organic, Panchagavya and, the castor cake + recorded the highest aryl sulfatase activity which was significantly superior to all other sources. The lowest was noticed with no in both years. Integrated use of 150% NPK +castor cake + (M 4 ) recorded significantly the highest aryl sulfatase activity (75.34, 51.21 and 69.31, 47.83 µg of p-nitro phenol released g -1 soil h - 1 at flowering, harvest during Rabi 2007-2008 and Kharif 2008, respectively) followed by 150% NPK +vermicompost + (M 4 S 3 ) which was at par with 100% NPK +castor cake + (M 3 ) at flowering in Rabi 2007-2008 and at both stages in Kharif 2008. However,at harvest in Rabi 2007-2008 conjunctive use of 150% NPK + castor cake + was at par with 150% NPK + vermicompost + (M 4 S 3 ). The lowest was noticed with control (M 1 S 1 ). The Aryl sulfatase activity in Rabi 2007-08 at harvest showed 22.67, 13.95 and 8.03% increase over no fertilisers with application of 150%, 100% and 50% NPK, respectively. But the % increase from 50% NPK to 100% NPK was 5.75% and from 100% NPK to 150% NPK was 6.52%. The % increase with castor cake + was 16.80%, vermicompost + was 11.68% and Panchagavya + was 6.44% over no. When compared to initial aryl sulfatase activity (45.24 µg p- nitro phenol released g -1 soil h -1 ), the highest percentage of increase was noticed with 150% NPK + castor cake + (13.20%). In Kharif 2008 at harvest, the % increase was 8.24, 11.62 and 20.14% with 50%NPK, 100%NPK and 150%NPK, respectively over no fertilisers. The % increase from 50% NPK to 100% NPK and 100% NPK to 150% NPK was 11.94% and 7.63%, respectively. The % increase with Panchagavya+, vermicompost+ and castor cake + was 3.76, 7.44 and 13.25%, respectively over no. These were increased up to flowering and later showed decrease. The increase in enzymatic activity with different organic may be attributed to the increasing population of micro organisms like bacteria etc, due to increased availability of substrate through which helps to releasing of these enzymes of extra cellular origin. Similar findings were reported by Rao and Raman (1996) for acid and alkaline phosphatases and Singaram and Kamalakumari (1996). Increase in enzyme activities at flowering stage enhanced root activity and the release of extra cellular enzymes like aryl sulfatase in to soil solutions during the active growth phase which resulted in higher rate of mineralization of nutrients in to soil. The results are in conformity with the findings of Sriramachandrasekharan et al.(1997). The correlation between different soil enzymes and soil available nutrient status was found to be positively significant. Dry root yield : There was significant difference observed with fertilizer levels, organic, Panchagavya and as well as with their interaction on dry root yield. Dry root yield was increased from 273 kg ha -1 to 315 kg ha -1 and 271 to 311 kg ha -1 with increased levels of application of fertilizers from 0% to 150% NPK. The highest dry root yield was observed in 150% NPK (315 and 311 kg ha -1 ) which significantly differed from any fertilizer level (Table 5). Among organic / Table 5: Effect of inorganic fertilizers, organic, Panchagavya and bio fertilizers on dry root yield (kg ha -1 ) of Ashwagandha at harvest during Rabi 2007-08 (I year) and Kharif 2008 (I year) Rabi 2007-08 (I year) Kharif 2008 (II year) Treatments Flowering Harvest Vermicompos Panchagavya Castor cake Vermicompos Panchagavya @ Castor cake @ 2.5 t ha -1 t @ 1 t ha -1 + @ 2.5 t ha - t @ 1 t ha -1 + 5% foliar spray spray + 1 + M 1-0% NPK 248 298 280 267 273 242 285 279 277 271 M 2-50% NPK 265 320 294 277 289 269 308 294 283 289 M 3-100% NPK** 279 344 315 289 307 281 325 310 300 304 M 4-150% NPK 287 348 317 305 315 287 333 318 308 311 273 328 302 285 272 313 301 292 5.47 2.79 3.92 2.00 5.03 2.56 4.50 2.30 at same or different level of sub 10.73 5.47 8.14 4.15 * - Bio fertilisers (Azospirillum + Phosphorus Solubilizing Bacteria), 100% NPK** = 60-50 - 40 kg NPK ha -1 HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 23 Asian J. Soil Sci., (June, 2013) 8 (1) :

Panchagavya and, application of castor cake + recorded significantly the highest dry root yield (328 and 313 kg ha -1 ). The highest dry root yield was observed with 150% NPK along with castor cake + (348 and 333 kg ha -1 ) (M 4 ) which was at par with 100% NPK + castor cake + (344 and 325 kg ha -1 ) (M 3 ). The lowest was noticed with control (248 and 242 kg ha -1 ) (M 1 S 1 ). Higher yields with 150% NPK might be due to high nitrogen, phosphorus, potassium and sulphur supply leads to increased number of branches, leaves and leaf area which might have helped in the efficient synthesis and translocation of photosynthates from the source to sink (Nigam et al., 1984; Praveen, 2000). The C:N ratio of castor cake was lower indicated rapid mineralization of nitrogen from castor cake. The higher yield due to integration of inorganic fertilizers and organic could be due to the higher yield attributing characters like root length and girth, higher dry matter production, higher supply of nutrients, favourable physical and biological environment in the soil leading to better root activity and nutrient absorption (Joy et al.,2005 and Mazumdar et al., 2002). As Ashwagandha is a root crop, improvement of soil physical environment might be helped in better development of roots. Conclusion : This study leads to the conclusion that the available S, aryl sulfatase adry root yield was increased with graded levels of NPK. Application of casto cake + showed superior results than other. Conjunctive use of 150% RDF+ castor cake + recorded the higher available S, aryl sulfatase activity and root yield. All the treatments showed build up of available S at harvest except control. Literature Cited Chesnin, L. and Yein, C.H. (1951). Turbidimetric method of sulphate sulphur in plant materials. Proc. Soil Sci. Soc. America., 15: 149-151. Joy, P.P., Savithri, K.E., Samuel Mathew, Thomas, J. and Abraham, C.T. (2005). Effect of mulch and sources of nutrients on growth yield and quality of black muslin (Curculigo archioides). J. Med. & Aromatic Plant Sci., 27: 646-656. Kumar, Alok, Dwivedi, A.K. and Dikshit, P.R. (2002). Long term influence of organic and inorganic fertilization on soil fertility and productivity of soybean-wheat system in a Vertisol. J.Indian Soc. Soil Sci., 50 (4): 472-475. Kumar, Alok and Yadav, D.S. (2005). Influence of continuous cropping and fertilization on nutrient availability and productivity of an alluvial soil. J. Indian Soc.Soil Sci., 53 (2): 194-198. Mazumdar, B., Venkatesh, M.S. and Kumar, K. (2002). Effect of nitrogen and FYM on yield and nutrient uptake of turmeric and different forms of inorganic buildup in an acidic Alfisol of Meghalaya. Indian J. Agric. Sci., 72 (9): 528-532. Natarajan, S. (2003). Studies of different organic and nitrogen fertilizers on soil fertility and sustained productivityin rice based cropping system. Ph. D Thesis, Tamil Nadu Agricultural University, Coimbatore, T.N. (INDIA). Nigam, K.B., Rawat, G.S. and Prasad, B. (1984). Effect of methods of sowing, plant density and fertility level on ashwagandha (Withania somnifera Dunal). South Indian Hort., 32(3): 329. Praveen, Y. (2000). Conjustive use of castor cake and nitrogenous fertilizers on the performance of carrot (Daucus carota L.). M.Sc Thesis, Acharya N.G. Ranga Agriculture University, Hyderabad, A.P. (INDIA). Rao, P.C. and Raman, S. (1996). Influence of plant cover and stage of crop growth on the activity of soil enzymes. Paper presented in 61st Annual Convention of the Indian Society of Soil Science held at Gujarat Agricultural University, GUJARAT, INDIA October 28th vember 1st. Singaram, P. and Kamalakumari, K. (1995). Long term effect of FYM and fertilizers on enzyme dynamics of soil. J. Indian Soc. Soil Sci., 43(3): 378-381. Sriramachandrasekharan, M.V., Ramanathan, G. and Ravichandran, M. (1997). Effect of different organic on enzyme activities in a flooded rice soil. Oryza, 34: 39-42. Tabatabai, M.A. and Bremner, J.M. (1970). Arylsulfatase activity in soil. Soil Sci. Soc. American Proc., 34: 225-229. ******** ****** **** HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 24 Asian J. Soil Sci., (June, 2013) 8 (1) :