Studies on evaluation of fertility status of soybean growing area of Latur and its adjacent tahsil

Introduction

Soil is a dynamic natural entity found in the upper layers of the Earth's surface, functioning as a crucial interface among the atmosphere, biosphere, hydrosphere, and geosphere. It serves as the foundation for most terrestrial life and is characterized by remarkable complexity. Soil quality encompasses a range of interrelated attributes, including physico-chemical properties such as pH, electrical conductivity, organic carbon, and calcium carbonate, all of which significantly influence the availability of vital nutrients for crop growth. By effectively managing these physico-chemical properties, the availability of essential nutrients in the soil can be enhanced. The presence of macro and micronutrients is critical for soil fertility and directly impacts crop yields. In any given area, crop health depends largely on the availability of soil nutrients and their profiles. These factors underscore the importance of thoroughly examining the physicochemical composition of agricultural soils. Assessing soil fertility involves measuring the accessible essential nutrients for plants and evaluating the soil's ability to provide a continuous supply of these nutrients to crops. Tissue tests offer an accurate representation of the nutritional status of plants, as leaf analysis indicates whether the soil can adequately meet the crop's nutrient demands. These tests should be conducted every two to five years, typically after nutrient levels in the leaves have stabilized. It's important to minimize interactions between crop levels in the plant and mineral contamination from sprays. When foliar fertilizers are applied, leaves from "control" plants that have not been treated should be thoroughly cleaned to eliminate any residue. Various factors affect the nutritional makeup of leaves, including soil moisture, texture, fertility, and fertilization techniques, which directly influence nutrient uptake. Additionally, leaf nutritional content can vary based on crop load, plant variety, rootstock, the presence of diseases and pests, weather conditions, and cultural practices such as weed control and pruning. These factors should be considered when analyzing leaf data. Leaf analysis aims to maintain nutrient levels within ideal ranges for optimal quality and yield, and appropriate corrective actions should be taken if any nutrient levels fall outside these ranges.

Materials and Methods

Nilanga taluka is one of the ten talukas (subdivisions) of Latur district in Maharashtra, India. It is located in the Marathwada region of the state. The taluka has 152 villages. Nilanga town, the administrative center of the taluka. The town is situated at an average elevation of 631 meters (2,070 ft) above sea level. Latur district, including Nilanga, lies on the Balaghat Plateau, with elevations ranging from 540 to 638 meters. To evaluate the soil fertility of Nilanga Tahsil surface soil samples (0-30 cm) were collected. The latitude and longitude of location were recorded at the time of soil sample collection, All the collected soil samples will be brought to the laboratory and dried under shade by spreading on white glazed sheets and covered with white coloured paper to avoid contamination with the extraneous material. After drying, a part of each sample meant for analysis were ground with wooden mortar and pestle, passed through a 0.5 mm sieve and preserved in paper bags with proper labeling for further estimation of primary nutrients. All necessary precautions were taken as outlined by (Jackson 1973) [8] was carefully followed to avoid contamination. The tissue samples were collected at flowering stage of soybean during August-September 2024. The collected leaf samples were brought to the laboratory. The samples were air dried on perfectly clean surface at room temperature for 2-3 days in dust free atmosphere free from any kind of contaminants. Samples were placed in oven at 60°C for 48 hrs. and grinded in an electric stainless steel mill using 0.5 mm sieve. Then the samples were placed in oven to dry for few hours more till constant weight and stored in well stopper plastic jars for analysis. pH, EC and OC were determined by standard procedure (Jackson, 1973) [8] . The Nutrient Index was calculated as per the formula suggested by (Ramamurthy and Bajaj, 1969) [20] . The nutrient status of the study area was estimated, delineated and categorized on the basis of the NIV. The secondary and micronutrient status of soybean growing area of Latur and its adjacent Tahsil depicted on a thematic map. A soil fertility map was prepared by using (Ramamurthy and Bajaj, 1969) [20] soil nutrient index.

Results and Discussion

Physico-chemical properties of soils of Soybean growing area of Nilanga Tahsil

The data (Table 1) indicated that, pH of soils of Soybean growing area of Nilanga Tahsil ranged from 7.3 to 8.5 with mean value of 7.7, SE 0.06 and CV 4.08%. The soil sample NU-5, NA-2 and NP-5 collected from Ansarwada, Umerga and Palapur village showed the lowest pH (7.3) while, the highest value (8.5) was recorded in soil samples NH-5collected from Hadga village, respectively. The soils were neutral to alkaline in reaction. On the basis of categorization of soil samples, out of 25 samples, 7 were neutral (28%) and 18 samples were alkaline (72%) in reaction. (Table 2). The data revealed that the EC of soils of Soybean growing area varied between 0.4 to 2.6 dSm -1 with mean value of 1.2 dSm -1 , SE 0.14 and CV 56.01%. The soil sample NP-4 and NY-2 collected from Palapur, Yelamwadi villages showed the lowest EC (0.4 dSm -1 ) however, the highest value (2.6 dSm -1 ) was recorded in soil samples NU-3 and NU-5 which collected from Umerga village, respectively (Table 1). As per categorization of soils of Soybean growing areas, out of 25 samples 12 (48%) samples were shows No deleterious effect on crops, 9 (36%) Critical for germination and 4 (16%) found Critical for salt sensitive crops (Table 2). The organic carbon content in soils ranged from 0.15 to 0.78 per cent an average value of 0.49 per cent, SE 0.04 and CV 42.91%. The soil samples NU-5 collected from Umerga village, respectively showed the lowest organic carbon content (0.15%). While, the highest value (0.78%) was recorded in soil sample NY-3 from Yelamwadi village (Table 1). On the basis of categorization of organic carbon content of soils of Soybean growing area, out of 25 samples, 11 (44%) soil samples were categorized as low in organic carbon content, 14 (56%) were medium with respect to organic carbon content (Table 2). The calcium carbonate content in soils ranged from 2 to 8.3 per cent with mean value of 4.5 per cent, SE 0.31 and CV 35.27%. The lowest calcium carbonate content (2%) was recorded in soil sample NA-5 collected from Ansarwada village whereas, the highest calcium carbonate content (8.3%) was recorded in the soil sample NU-1 collected from Umerga village (Table 1). Out of 25 soil samples, 3 (12%) soil samples were No calcareous, 15 (60%) Calcarious and 7 (28%%) soil samples were rated as highly calcareous (Table 2). With respect to soils of Nilanga tehsil, Soil were shows pH range neutral to alkaline in reaction. The alkaline reaction is probably due to the presence of sufficient free lime content (Kaushal et al, 1986) [11] and basalt alluvial parent material rich in alluminosilcate alkaline earth from which these soils are derived. (Challa et al, 1998) [3] similar type of finding were reported by Waghmare et al. (2008) [27] recorded that the soils of Ausa tahsil ranged from 7.05 to 8.9 with an average value of 8.07. The values of EC obtained in analysis were found in desirable range as proposed by Richard and Cambell (1948) [22] , when EC exceed 4 dSm -1 , the salt present become harmful to the crop growth. Ajgaonkar and Patil (2017) [1] reported that the EC were ranged from 0.20 to 1.70 dSm -1 from the soils of Aurangabad district. These values of EC are safe for crop growth. Ushashri et al. (2019) [25] found that the EC ranged from 0.02 to 1.48 dSm -1 in soil samples collected from Bhudargad tahsil of Kolhapur district.

The data further revealed that overall soil samples were low to medium in organic carbon content. Reason behind the existence of variation in organic carbon content as Lower to medium range might be due to high temperature of Latur District (up to 41.5) and good aeration in the soil increased the rate of oxidation of organic matter resulting reduction of organic carbon content. Inadequate supply of organic manures and use of imbalanced chemical fertilizers along with poor agricultural management practices like soil tillage, mono or diversified cropping pattern, burning of trashes after harvesting etc. Kashiwar et al. (2019) [10] noticed that the organic carbon content ranged from 2.7 to 8.6 g kg -1 from the soils of Sakoli tahsil of Bhandara district.

According to categorization, it was observed that soils of Soybean growing area of selected villages were calcareous to highly calcareous in nature. It might be due to relatively more accumulation of CaCO 3 in soils and associated black soil may be partly associated with their recent origin with rich in alkali earth and partly due to calcification process prevalent in this region (Joshi, 2000) [9] . Similar finding of calcium carbonate (13.0 to 156.0 g kg -1 ) was recorded in swell shrink soils of Vidharbha region (Padole and Mahajan, 2003) [15] .

Status of primary nutrients in soils of Nilanga Tahsil.

The data (Table 3) revealed that there was wide range of variation in the available nitrogen in these soils. It ranged from 175 to 314 kg ha Thus based on Soils of Nilanga Tahsil. Nitrogen shows Low to high in range. The lower content of available nitrogen in these soils are associated with, Low content of organic matter and low total nitrogen reserve and in term C:N ratio of immobilized form of nitrogen (Malewar, 1995) [12] . These results are in confarmatory with results reported by Waghmare and Takhankar (2007) [26] in soils of Ausa and Nilanga tahsil of Latur district where N content ranged from 102.22 to 385.72 kg ha -1 and 100.3 to 366.91 kg ha -1 , respectively. It was infered from the value that all soil samples were low to medium in available phosphorus. The low available phosphorus might be due to the higher phosphorus fixing capacity of black cotton soils of Latur district that prevent the soil phosphorus to come in soil solution. The swell -shrink soils of Maharashtra were very low to high in available phosphorus content as reported by Patil and Sonar (1994) (17) . Similarly, available P ranged from 10.0 to 19.1 kg ha -1 in soils of Marathwada region (Waikar et. al. 2004) [28] . Further data revealed that the potassium content in soils of Soybean growing area categorized as Medium to high. The high content of K is due do presence of potassium rich mineral in soil and associated black soils (Gajbe et al. 1976) [5] . Chaudhari and Kadu (2007) [4] reported that the available K of soil with an average value of 428.2 kg ha -1 was recorded in soils of Dhule tahsil of Dhule district.

Status of secondary nutrients in soils of Nilanga Tahsil.

The available Sulphur content of soils ranged from 9.12 to 38.05 kg ha -1 with an average value of 20.94 kg ha -1 , SE 1.56 and CV 37.23%. The lowest content (9.12 kg ha -1 ) of available Sulphur was recorded in sample NU-2 collected from Umerga village whereas, the highest content (38.05 kg ha -1 ) was recorded in soil sample NP-5 collected from Palapur village (Table 5). Out of 25 soil samples, 2 (8%) samples were found low while, 9 (36%) samples were found medium and 14 (56%) high in available Sulphur content (Table 6). The exchangeable calcium varied from 8.1-54.8 cmol kg -1 with a mean value of 39.67 cmol kg -1 , SE 3.07 and CV 38.79%. The lowest exchangeable calcium (8.1 cmol kg -1 ) was found in the village of Hadga (sample no. NH-1), while the highest exchangeable calcium (54.8 cmol kg -1 ) was found in the villages of Palapur and Yelamwadi (sample no.NP-5 and NY-1) (Table 5). Out of 25 soil samples from, all 25 samples (100%) had a high exchangeable calcium content (Table 6).

The status of exchangeable magnesium in the soils of studied area was ranged from 9.45-38 cmol (p + ) kg -1 with the mean value of 20.09 cmol (p + ) kg -1 , SE 1.49 and CV 37.29%. The minimum exchangeable magnesium (9.45 cmol (p + ) kg -1 ) was observed in the village of Hadga (sample no NH-4) whereas maximum exchangeable magnesium (38 cmol (p + ) kg -1 ) was observed in Palapur village (sample no NP-1) (Table 5). Among the 25 soil samples, all 25 samples (100%) were in the high category. (Table 6). Based on Nilanga data, The available sulphur shows low to high in range. This might be expected due to the presence of Fe and Al oxides in surface soils. Similar results were also reported by Medhe et al. (2012) [13] and Kashiwar et al. (2019) [10] . The high status of exchangeable calcium and Magnesium in these soils may be a result of the dry and semidry environments causing an accumulation of metallic cations in calcareous soil.

Calcium is the main cation on the soil exchange complex and in the soil solution because limestone, calcite is the parent material. Ravte (2008) [21] reported that the exchangeable calcium and magnesium content from Ausa tahsil of Latur district were ranged from 11.05 to 50.7 and 2.6 to 28.9 cmol (P+) kg -1 , with a mean value of 31.67 and 18.2 cmol (P+) kg -1 . Similar findings were also reported by Bacchewar and Gajbhiye (2011) [2] .

DTPA-Micronutrient status in soils of Nilanga Tahsil

The DTPA-Zn content in soils was varied from 0.12 to 0.98 mg kg -1 with an average value 0.64 mg kg -1 , SE 0.05 and CV 46.08%. The minimum Zn content (0.12 mg kg -1 ) was recorded in soil samples NH-1 and NH-4 collected from Hadga village, respectively, Whereas, the maximum content (0.98 mg kg -1 ) was recorded in samples NA-1 collected from Ansarwada village (Table 7). The data (Table 8) further revealed that among 25 samples, 7 (28%) samples were low, 18 (72%) were medium in zinc content.

The data pertaining to Fe varied from 1.7 to 9.1 mg kg -1 with an average value of 5.5 mg kg -1 , SE 0.58 and CV 53.06%. in soils of selected villages of Latur district. The lowest value (1.7 mg kg -1 ) was observed in soil sample NH-1 collected from Hadga village. Whereas, the highest value (9.1 mg kg -1 ) was recorded in soil sample NU-3, NP-2, NP-5 and NY-3 collected from Umerga, Palapur and Yelamwadi villages (Table 7). As per the categorization of soil samples, out of 25 samples, 9 (36%) were low, 3 (12%) were medium and 13 (52%) were high in available Fe content (Table 8). DTPA-Cu varied from 8.1 to 20.32 mg kg -1 with an average value 14.52 mg kg -1 , SE 0.70 and CV 24.16%. The lowest available Cu content (8.1 mg kg -1 ) was noted in soil sample NH-5 collected from Hadga village. Whereas, the highest available Cu content (20.32 mg kg -1 ) was noted in soil sample NH-1 collected from Hadga village (Table 7), respectively. All 25 (100%) soil samples were high in copper content (Table 8).

The data on DTPA-Mn showed that, it was varied from 1.1 to 9.6 mg kg -1 with an average value 2.92 mg kg -1 , SE 0.51 and CV 88.96% in soils of Soybean growing of Latur district. The lowest content (1.1 mg kg -1 ) of Mn was observed in orchard soil NH-4 and NP-3 collected from Hadga and Palapur villages while, the highest value (9.6 mg kg -1 ) was recorded in soil sample NU-2 collected from Umerga village (Table 7). According to categorization of soil samples, out of 25 samples, 13 (52%) Low, 8 (32%) soil samples were medium in manganese content and 4 (16 per cent) were found to be high with respect to manganese content. (Table 8). Zinc shows low to Medium range in soils of Nilanga tahsil. Low content of zinc, might be because the zinc cations are heavily charged to their oxides or hydroxides in an alkaline environment, which reduces the zinc's availability. Similar findings were also found to be confirmatory with Meena et al.

(2006) [14] , Gosavi and Chaudhari (2016) [7] . It is seen from the result that soil samples were low to high in Fe content. High content of Fe due to the presence of Fe in the octahedral layer of silicate clays, especially those with clay minerals with a 2:1 composition (Smectite). Fertilizer applications with Fe content cause the release of Fe from the clay under specific soil conditions, increasing the concentration of Fe in the soil solution. Similar results were reported by Kashiwar et al. (2019) [10] . DTPA Copper shows high in soils. High copper concentrations may result from the presence of chalcocite and cuprite minerals in soils and basaltic parent materials. Shinde (2007) [23] reported that the DTPA-extractable copper content was ranged from 0.32 to 17.5 mg kg-1 and 0.74 to 9.42 mg kg-1 from Udgir and Deoni tahsils in Latur district. Similar findings were also reported by Meena et al. (2006) [14] .

Mostly Mn shows medium to high in range. The high Mn status in these soils might be due to the, these soils have higher ferromagnesium mineral concentrations than soils derived from basaltic parent minerals, or it might be because these soils have more magnetic mineral pressure. Waghmare and Takankhar (2007) [26] found that the DTPA extractable manganese content ranged from 1.23 to 13.57 mg kg-1 with an average value of 7.57 mg kg-1 from soils in Ausa tahsil of Latur district. Similar results were also reported by Pradeep et al. (2006) [18] .

Total nutrient content in Soybean plant of Nilanga

Tahsil (N, P, K, S, Fe and Zn) Total nitrogen content of Soybean leaves varied from 2.23 to 4.6 per cent with an average of 3.08 per cent, SE 0.17 and CV 27.88%. The lowest amount of total nitrogen (2.23%) was recorded in leaves samples NP-5 collected from Palapur village whereas, the highest amount (4.6%) was recorded in leaves sample NY-3 collected from Yelamwadi village (Table 9). On the basis of categorization (Table 10), among 25 samples, 13 (52%) leaves samples was Low in total N content and 12 (48%) medium in total N content. Total phosphorus content of Soybean leaves ranged from 0.11 to 0.47 per cent with an average of 0.22 per cent, SE 0.02 and CV 47.87%. The less amount of total P (0.11 per cent) was noted in leaves sample NH-5 collected from Hadga village, respectively. However, the high amount of total P (0.47%) was recorded in leaves NP-5 collected from Palapur village (Table 9). The data further revealed that Out of 25 leaves samples (Table 10), 14 (56%) samples were categorized as low and 11 (44%) samples medium in total phosphorus content in Soybean leaves. Total potassium content of Soybean leaves varied from 2.1 to 6.4 per cent with a mean value 4.89 per cent, SE 0.24 and CV 25.11%. The minimum content of total K (2.1%) was recorded in leaves samples NU-2 collected from Umerga village. Whereas, maximum content (6.4%) was recorded in leaves samples NP-5 collected from Palapur village (Table 9). Out of 25 leaves samples 18 (72%) leaves samples were low and 7 (28%) Medium in total potassium content (Table 10). Total Sulphur content in leaves ranged from 0.12 to 3.8% with a mean value of 2.69%, SE 0.26 and CV 49.72%. The less amount of total S (0.12%) was noted in leaves sample NU-2 collected from Umerga village. However, the high amount of total S (3.8%) was noted in leaves sample (NU-1, NA-1, NA-3 and NP-5) collected from Umerga, Ansarwada and Palapur villages (Table 9). Out of, 25 soybean leaves samples, 3 (12%) samples low, 5 (20%) leaves samples were medium, while 17 (68%) leaves samples high in Sulphur content ( 9). Out of, 25 soybean leaves samples, 4 (16%) samples low and 21 (84%) leaves samples were medium in zinc content (Table 10). Thus, based on overall data of study area. It indicating that majority of Soybean plant samples showed low to medium in Nitrogen, Phosphorus and Zinc content. These results confirm the findings reported by Ghatala et al (2004) [6] studied the nutrient concentration in pomegranate Plant of Jaipur district, Rajasthan and reported that nitrogen concentration in leaves ranged from 0.65 2.35 per cent. Singh and Kumar (2012) [24] found that P contents ranged from 0.184 to 0.276 per cent in Pomegranate leaves. (Parwe 2013) [16] who found that Zn in plant was 50.0 to 90.2 mg kg -1 in pomegranate orchards of Beed district.

Total Potassium content of Soybean leaves mostly categorized medium to high in range. These results are in resemblance with the findings of (Raghupati and Bhargava 1998) [19] . (Parwe 2013) [16] found that K contents ranged from 1.02 to 9.71per cent.

The total Sulphur content in Soybean leaves showed low to high in range. These results are in resemblance with the findings of (Raghupati and Bhargava 1998) [19] . Total Iron content of Soybean leaves mostly categorized low to high in range. (Parwe 2013) [16] observed the range of iron in leaves was 124.0 to 3.10.0 mg kg -1 in pomegranate plant leaves of Beed district.

Soil nutrient index in soils of Nilanga tahsil.

On the basis (Table 11and Fig

References

1. Ajgaonkar SS, Patil SS. Soil health of soils in Aurangabad district (Maharashtra), India. An Asian Journal of Soil Science. 2017;12(1):121-127.
2. Bacchewar GK, Gajbhiye BR. Correlation studies on secondary nutrients and soil properties in soils of Latur district of Maharashtra. Research Journal of Agricultural Science. 2011;2(1):91-94.
3. Challa O, Vadivelu S, Sehgal JL. Soils of Maharashtra for optimizing land use. NBSS Pub: 54 (soils of India series) NBSS and Land Use Planing Nagpur, India; 1998. p. 112.
4. Chaudhari RD, Kadu PP. Assessment of fertility status of the soils of Dhule tehsil of Dhule district. Paper presented at: state level seminar on soil health enhancement for food and environmental security; October 12-13, 2007; Marathwada Agril. Univ. Parbhani.
5. Gajbe MV, Londe MG, Varade SB. Soils of Marathwada. Journal of Maharashtra Agricultural University. 1976;(26):55-59.
6. Gathala MK, Yadav BV, Singh SD. Mineral nutrient status of pomegranate orchards in Jaipur district of Rajasthan. J. Indian Soc. Soil. Set. 2004;52(2):206-208.
7. Gosavi NI, Chaudhari RD. Micronutrient status in soils of Shirpur Tahsil of Dhule district (M. S.), India. An Asian Journal of Soil Science. 2016;11(2):353-357.
8. Jackson ML. Soil Chemical Analysis. Prentice Hall of India Pvt. Ltd; 1973. p. 498.
9. Joshi SV. Morphology, Genesis and Classification of Black Soil. Series A, seminars No 42. 2000;179-185.
10. Kashiwar SR, Kundu MC, Dongarwar UR. Assessment and mapping of soil nutrient status of Sakoli tahsil of Bhandara district of Maharashtra using GIS techniques. Journal of Pharmacognosy and Phytochemistry. 2019;8(5):1900-1905.
11. Kaushal GS, Tembare BR, Sinha SB. Morphology and taxonomy of black soil under bargi irrigation project in Madhya Pradesh. J. Indian Soc. Soil Sci. 1986;34(2):329333.
12. Malewar GU. Micronutrient availability as influenced by cropping pattern in Marathwada region of Maharashtra. J. Maharashtra Agric. Univ. 1995;20(2):330-333.
13. Medhe SR, Takankhar VG, Salve AN. Correlation of chemical properties, secondary nutrient and micronutrient anion from the soils of Chakur tahsil of Latur district, Maharashtra. An International Peer-Reviewed Journal. 2012;1(2):2318-5037.
14. Meena HB, Sharma RP, Rawat US. Status of Macro-and Micronutrients in Some Soils of Tonk District of Rajasthan. Journal of the Indian Society of Soil Science. 2006;54(4):508-512.
15. Padole VR, Mahajan SB. Status and release behavior of potassium in swell-shrink soils of Vidharbha region of Maharashtra. J. Maharashtra Agric. Univ. 2003;28(1):3-7.
16. Parwe SK. Nutritional evaluation of pomegranate orchards of south east region Beed district by soil and leaf analysis. VNMKV; 2013.
17. Patil YM, Sonar KR. Status of major and micronutrient of swell-shrink soils of Maharashtra. J. Maharashtra Agric.Univ. 1994;19(2):169-172.
18. Pradeep RG, Dasog S, Kuligod VS. Nutrient status of some groundnut growing soils of upper Krishna command area, Karnataka. Karnataka Journal of Agricultural Science. 2006;19(1):131-133.
19. Raghupathi HB, Bhargava BS. Leaf and soil nutrient diagnostic norms for pomegranate. J. Indian Soc. Soil Sci. 1998;46(3):412-416.
20. Ramamoorthy B, Bajaj JC. Available N, P and K status of the Indian soils. Fertilizer News. 1969;14(8):24-26.
21. Ravte SS. Studies on status of available secondary nutrient and micronutrient anions in Ausa and Nilanga tahsils of Latur district. Vasantrao Naik Marathwada Krishi Vidyapeeth; 2008.
22. Richard H, Cambell P. In diagnosis and improvement of saline and alkali soils. Hand book, US. Dept. Agri; 1948. p. 60.
23. Shinde YR. Physio-chemical properties and nutrient availability of soils of Udgir and Deoni tahsils of Latur district. Vasantrao Naik Marathwada Krishi Vidyapeeth; 2007.
24. Singh J, Kumar R. Influence of soil nutrient status on yield and qualitative attributes of pomegranate (Punica granatum L.) and ber (Zizyphus mauritiana L.). Hort. Flora Res Spectrum. 2012;1(1):5-12.
25. Ushasri B, Kumar CM, Patil DS, Pawar RB. GPS and GIS based soil fertility maps of micronutrient status of Bhudargad tahsil of Kolhapur district (M.S.). International journal of Chemical Studies. 2019;7(6):6-10.
26. Waghmare MS, Takankhar VG. Status of available nutrients in soils of Ausa tahsil of Latur district. Paper presented at: state level seminar on soil health enhancement for food and environmental security; October 12-13, 2007; Vasantrao Naik Marathwada Agricultural University Parbhani.
27. Waghmare MS, Indulkar BS, Bavalgave VG, Mali CV, Takankhar VG. Chemical properties and micronutrient status of some soils of Ausa tahsil of Latur, Maharashtra. An Asian Journal of Soil Science. 2008;3(2):236-241.
28. Waikar SL, Malewar GU, More SD. Elemental composition of humic acid fulvic acid in soils of Marathwada region of Maharashtra. J. Maharashtra Agric. Univ. 2004;29(2):127129