1. Ph.D in Soil Science and Agricultural Chemistry from famous Banaras Hindu University, Varanasi, Uttar Pradesh, India.

2. Posse’s more than 11 years of experience as Principal Scientist. Currently working on SOIL FERTILITY AND CITRUS NUTRITION MANAGEMENT. Handled so far 15 research Projects completed with 7 Research Projects are in progress at present both as Principal Investigator as well as Associate in addition to 8 Research Projects externally funded (includes 3 international projects) and 1 Contract research Project as principal Investigator, apart from many in-house projects, mostly multi-disciplinary in nature. Salient findings are briefly highlighted: Characterization of Salt Affected Soil, Transformation and Availability of Nutrients, Nutrient Constraints Analysis of Citrus Orchards of India, Development of Soil-Plant Nutrient Diagnostics, Physiological Aspects of Citrus Nutrition, Modelling Orchard Efficiency vis-à-vis Soil Properties, Microirrigation and Fertigation scheduling, Integrated Nutrient Management, Site Specific Nutrient Management, Development of Soil Fertility Map as Decision Support Tool, Intercrop-based Yield Prediction Models, Microbial Consortium and Substrate Dynamics.

3. Authored 11 books(Including Advances in Citrus Nutrition, Springer-Verlag, Netherlands), 33 book chapters, 87 Research Papers in Indian Journals,32 Review Papers in Indian journal,252 Abstracts in Seminar/Symposium,36 Scientific/Popular Articles,53 Research Papers in Foreign Journal, 15 Policy Review Papers in Foreign Journal, 14 Technical Reports, 8 Technical Bulletins, 8 Extension Folders, 16 Extension Bulletins,1 Manual, 1 Status Paper, 17 Research Papers in Proceedings of Seminar/Symposia/Conference. Edited 13 Annual Reports, 41 Newsletters, and 15 Abstracts and Proceedings of National Seminar/Symposium.

1. Employment

Sr. No.Positions heldName of the Institution / Organisation
15.12.2006ContinuePrincipal ScientistNational Research Centre for Citrus, Nagpur, Maharashtra
25.12.19984.12.2006Sr. ScientistNational Research Centre for Citrus, Nagpur, Maharashtra
39.11.19944.12.1998Scientist `SS’
Soil Science
National Research Centre for Citrus, Nagpur, Maharashtra
Soil Science
National Bureau of Soil Survey and Land Use Planning, Nagpur, Maharashtra.
Soil Science
National Academy of Agricultural Research and Management, Hyderabad, Andhra Pradesh.

2. Experience in soil-plant management

Extensively pursued research work on different aspects of citrus nutrition like nutrient constraints analysis of citrus orchards by developing DRIS-based soil-plant nutrient diagnostics, orchard efficiency modelling, targeted yield-based site specific nutrient management exploiting spatial variability using geospatial tools, nutrient dynamics studies, transformation of soil microbial biomass nutrients within citrus rhizosphere and soil fertility map as decision support tool for fertilizer recommendation through 13 projects as Principal Investigator and 18 projects as Co-Principal Investigator. Authored the books like Citrus: Soil and Climate, Citrus Nutrition both published by IBDC, Lucknow and editor of book entitled “Advances in Citrus Nutrition” by Springer-Verlag, Netherlands, in addition to co-author of book on “Khatta Nimboo” published by ICAR, New Delhi, to cite few of them in soil fertility, citrus rhizosphere specific microbial consortium loaded INM module, and soil carbon loading as climate change mitigation option, fertigation scheduling, nutrient mapping.

3. Trainings

1. Foundation Course on Agricultural Research Project Management at National Academy of Agricultural Research and Management, Hyderabad during Dec., 05 1989 – Apr. 30,1990.

2. Subject Matter Training in Soil Science – Pedology at National Bureau of Soil Survey and Land Use Planning, Nagpur, during April 30 – Nov. 09, 1990.

3. Biodynamic and Organic Farming organized by Central Institute of Sub-Tropical Horticulture, Rehmankhera, Lucknow, Uttar Pradesh during April 18-20, 2002.

4. Winter School on Integrated Nutrient Management for Sustainable Agriculture sponsored by Indian Council of Agricultural Research, New Delhi and organized by Department of Agricultural Chemistry and Soil Science, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola during September 2-23, 2002. Adjudged to be the Best Trainee.

5. Personnel Management Information System Network (PERMISNET) training organised by IASRI, New Delhi during September 1-2, 2004.

6. Training program on Intellectual Property Right on August 31, 2006, at Intellectual Property Training Institute, Dept. of Industrial Policy & Promotion, Ministry of Commerce & Industry, Govt. of India, CGO Complex ‘C’ Block 3rd Floor, Seminary Hills, Nagpur 440 006 (Patent Information System).

7. Training program on Leadership for Innovation in Agriculture organized by National Institute of Agricultural Extension Management (MANAGE) at Hyderabad, Andhra Pradesh, during July 19-23, 2010

8. Training program on Leadership for Innovation in Agriculture at Indian Institute of Management, Lucknow, Uttar Pradesh, during Feb. 21-25, 2011

9. Sensitization-cum-Training workshop for the PME Cell Incharge (Nodal Officer) of HYPM, at CIFE, Mumbai on Feb. 2, 2012.

10. International Workshop on Alternative Analytical Technology for Soil Nutrient Analysis a project supported by Department of Science and Technology, Govt. of India, New Delhi and Murugappa Group at Shri AMM Murugappa Chettiar Research Centre, Taramani, Chennai, Tamil Nadu during Nov. 25 to 27, 2011.

11. Innovative Teaching for Improved Learning, USAID, Cornell Univ. College of Agriculture and Life Sciences, University of Illinois at Urbana-Chapampaign College of Agricultural, Consumer and Environmental Science,New Delhi, India, during 16-18 July, 2012.

12. Management Development Programme on Leadership Development, at National Academy of Agricultural Research and Management, Hyderabad, during 8 – 19 Oct., 2012.

13. One day Training Programme on Indian Patenting Procedures: Commercialization of patents” (National Agriculture Innovation Fund, ICAR, New Delhi In collaboration with Rajiv Gandhi National Institute Of Intellectual Property Management ) held on 11-08-2016 and 26-03-2018 at ICAR-CCRI, Nagpur.

4. Inter-disciplinary/Inter institutional works

1. Extensively pursued research work on different aspects of citrus nutrition like nutrient constraints analysis of citrus orchards by developing DRIS-based soil-plant nutrient diagnostics, orchard efficiency modelling, targeted yield-based site specific nutrient management exploiting spatial variability using geospatial tools, nutrient dynamics studies, transformation of soil microbial biomass nutrients within citrus rhizosphere and soil fertility map as decision support tool for fertilizer recommendation through 13 projects as Principal Investigator and 18 projects as Co-Principal Investigator. Authored the books like Citrus: Soil and Climate, Citrus Nutrition both published by IBDC, Lucknow and editor of book entitled “Advances in Citrus Nutrition” by Springer-Verlag, Netherlands, in addition to co-author of book on “Khatta Nimboo” published by ICAR, New Delhi, to cite few of soil fertility, citrus rhizosphere specific microbial consortium loaded INM module, and soil carbon loading as climate change mitigation option, fertigation scheduling, nutrient mapping

2. Credited with 110 peer reviewed research papers (81 papers in Indian journals and 29 papers in foreign journals), 46 policy review papers (29 in Indian journals and 13 in foreign journals; 64 Invited lead papers). Received 12 awards inclusive of S.N. Ranade Award for Excellence in Micronutrient Research, FAI Silver Jubilee Award, International Plant Nutrition Institute-FAI Award, Netaji Subhash Chandra Bose Award for Excellence, etc. in addition to association with editorial board of 49 international (J Plant Nutrition, Commun. Soil Science and Pl.Anal., J.Afri. Agri. Res., Adv. Hort. Sci., Agrotechnology etc.) and 13 national journals

3. Life Member of 25 academic societies and honorary member of World Association of Soil and Water Conservationists. Fellow of 7 academic societies (Maharashtra Academy of Sciences, National Environmental Science Academy, Environmental Research Academy, Indian Society of Citriculture, Indian Society of Soil Science, Indian Society of Agricultural Chemists, Confederation of Horticultural Associations of India and National Academy of Biological Sciences). Evaluated 37 M.Sc. and 6 Ph.D. theses, and delivered 26 lectures in summer/winter schools/ refresher courses.

4. Initiated leaf analysis advisory service. Offered international training course on “INM in Citrus” as a part of ICAR international training curriculum and credited with NRCC Soil Science Lab as ICAR list of nationwide referral laboratories. Paper setter on advance courses on Soil Fertility and Soil Chemistry across 6 agricultural universities in India. Member of the Management Committee of two ICAR based organizations, NRC on Seed Spices, Ajmer (Rajasthan) and NRC on Pomegranate, Solapur (Maharashtra); Technical Advisory Committee, Central Institute of Horticulture, Nagaland from Ministry of Agriculture, New Delhi and Indian Institute of Vegetable Research, Varanasi, Uttar Pradesh.

5. Invited as Citrus Expert by Govt. of Nepal in 1999 under Indo-Nepal MOU and keynote speaker in World Citrus Congress held at Wuhan, (China) in 2008. Developed vision document for citrus development in Meghalaya and Andhra Pradesh as Team Leader and associated as Member of multi-disciplinary delegation for working out the roadmap for citrus development in Madhya Pradesh, Marathwada region of Maharashtra, Tripura and Mizoram. Acted as Coordinator of ICAR-sponsored Summer School on “Hi-tech Intervention on Citrus” and four Mini-Mission-I trainings for extension personnel of Mizoram, Manipur and Nagaland of northeast India.

5. Project Handled

(a) Major R & D initiatives launched including those relating to IPR/ Patent/WTO etc.
Multi-disciplinary projects:
Principal Investigator of 7 research projects (4 completed and 3 in progress)
Principal Investigator of 2 ICAR funded research projects (Completed)
Principal Investigator of 3 internationally funded projects (completed)
Principal Investigator of 1 Consultancy project (Completed)
Co-Principal Investigator in 18 projects
(15 completed and 4 in progress)

(b) Identification of suitable soil for sustained productivity of Nagpur mandarin (Citrus reticulata Blanco) –ICAR funded Relationship of soil properties with orchard efficiency and fruit quality, and identification of suitable soils by fixing the thresholds of soil properties.

(c) Delineation of suitable soils for sustained productivity of Sweet orange (Citrus sinensis Osbeck) cultivar mosambi – ICAR funded Relationship of soil properties with orchard efficiency and fruit quality, thresholds of soil properties, and quantification of soil factors in relation to sweet orange decline

(d)Site specific nutrition management in Nagpur mandarin (Citrus reticulata Blanco) in central India – funded by IPNI, Gurgaon Soil fertility changes in relation to macronutrient fertilization with and without macronutrients, nutrient interaction versus fruit yield and quality; and site specific fertilizer response versus recommended doses of fertilizers

(e) Site specific nutrient management in mosambi sweet orange (Citrus sinensis Osbeck) – funded by IPNI, Gurgaon Comparison on behaviour of sweet orange on soil types varying in nutrient supplying capacity, response of N, P and K fertilization on growth, yield and quality of sweet orange with and without micronutrients, maximising yield efficiency in relation to soil types, soil fertility changes in relation to fruit yield and quality, changes in leaf nutrient composition in relation to fruit yield and quality

(f) Development of soil fertility map as decision support tool for fertilizer recommendation in citrus – Funded by IPNI, Gurgaon Assessment of soil fertility variation through spatial soil fertility variogram; Assessment of variation in leaf nutrient composition through spatial variogram; delineation of production zones and fertilizer rates vis-à-vis soil test value; development of temporal soil fertility variogram and changes in fertilizer recommendation; development of spatial soil fertility map as decision support tool for fertilizer recommendation.

(g) Network Project on Organic Horticulture: Organic production of Nagpur mandarin Funded by – ICAR Nutrients supplying capacity of various organic substrates; Changes in soil physico-chemical and microbiological properties; changes in insect pests and disease dynamics; and response of organic substrates on fruit yield, quality and post-harvest life.

(h) National network project on drip irrigation system in perennial horticultural crops – Citrus – ICAR funded
Identification of water requirement at different stages of growth and development; evaluation of crop water use at different stages of growth and weather conditions; development of irrigation schedule and interaction of soil moisture and nutrient through fertigation

(i) Automatic irrigation scheduling in fertigation through microjet irrigation system in Nagpur mandarin (Citrus reticulata Blanco)- ICAR funded K-fertigation through microjet irrigation; automatic irrigation scheduling with drip irrigation system; effect of different microjet irrigation system; soil moisture distribution pattern; and economic feasibility of various micro-irrigation systems

(j) Analysis of Citrus rhizosphere environment for climate resilience-based production management. A project under National initiative on climate resilent agriculture (NICRA) – Funded by ICAR Analysis of climate variability and extreme events vis-à-vis impacts on citrus flowering and production pattern across mandarin belts; impact of climate change on nutrient dynamics of rhizosphere, water use, flowering, fruiting, maturation, fruit quality, diversity and population dynamics of insect pests and their bioagents; and evaluating various adaptation strategies addressing various production constraints.

Technologies Developed

1. Balanced Fertilization:Citrus is considered highly nutrient responsive crop. Balanced fertilization is considered one of the effective ways of not only cutting the cost of production, but doubling the farmers income as well. In this regard, 4R Nutrient steward concept is considered by for the best strategy towards balanced fertilization.

1.1 Diagnosis of Nutrient Constraints:Research farm to farmers field the gap in productivity level of Asian is the major cause of concern, and the absence of adequate information on soil fertility and plant nutrition is frequently ascribed. The subject is further complicated by merely any reference values available with regard to diagnosis of nutrient constraints in different commercial citrus cultivars. The diagnostics available for other commercial cultivars have not provided the desired results when evaluated under varied citrus agro climates. Resultantly, the orchards continue to produce sub-optimally due to increasing gap between the amounts of nutrients added to that of annual demand with orchard age. Such emerging scenario simply goes un-noticed to the citrus growers, which is more worrying.

Many attempts on similar lines were earlier made to identify nutritional problems of citrus orchards in countries like China including other parts of India employing a variety of diagnostic methods, amounting to many discrepancies in the interpretation of results. The nutrient constraint diagnosis hence, seldom addresses the problems that originally exist in field and, therefore, not sufficed to inflict the desired response of fertilization. Such differences in outcome of diagnosis can be overcome by developing a suitable nutrient diagnostics very specific to a cultivar, soil type, and climate. These studies have confirmed that large amounts of fertilizers are not always essential for maximum yields. Many methods have been used to develop and diagnose nutritional problems, but none of them is considered serving the purpose in entirety. Once a suitable nutrient diagnostics are developed, their application in mapping the distribution of different kinds of nutrient deficiencies becomes next important issue at individual orchard level or at location level. Application of geospatial tools in precision mapping of nutrient constraints is envisaged. Any attempt of this kind, promise to ensure the sustainability in citrus production strongly level of low orchard productivity. The poor response of fertilization is largely attributed to non-redressal of nutritional problems originally existing in field in the absence of cultivar specific nutrient diagnostics. The premier citrus cultivars of India, namely Nagpur mandarin (Citrus reticulata Blanco), ‘Mosambi’ sweet orange (Citrus sinensis Osbeck), Malta sweet orange (Citrus sinensis Osbeck), (Citrus sinensis Osbeck),Khasi mandarin (Citrus reticulata Blanco), Acid lime (Citrus aurantifolia Swingle), Kinnow mandarin (Citrus deliciosia Lour. x Citrus nobilis Tanaka) were extensively surveyed. DRIS indices were developed based on leaf analysis data in relation to fruit yield and accordingly nutrient constraints were identified.

1.1.1 Leaf Analysis- Based Diagnostics: The leaf nutrients norms were developed employing two diverse diagnostic methods (Field Response Studies and Survey/Modelling and Diagnosis) using different citrus cultivars. The difference in diagnostic methods apart from the agroclimate and nutrient uptake behavior of cultivar are the major contributory factors towards variation in reference values being recommended in relation to yield.
Nagpur mandarin: Optimum leaf nutrient standards for ‘Nagpur’ mandarin: 2.24-2.40% N, 0.07-0.110% P, 1.18-1.56% K, 1.32-1.55% Ca, 0.48-0.67% Mg, 110-132 ppm Fe, 29-43 ppm Mn, 8-14 ppm Cu and 19-30 ppm Zn.
Khasi mandarin : Optimum leaf nutrient standards for ‘Khasi’ mandarin: 2.23-2.49% N, 0.10-0.11% P, 1.86-2.12% K, 2.12-2.32% Ca, 0.28-0.38% Mg, and 148-180 ppm Fe, 72-85 ppm Mn, 10-19 ppm Cu and 24-39 ppm Zn.
Kinnow mandarin: Optimum leaf nutrient standards for ‘Kinnow’ mandarin: 2.28-2.53 % N, 0.10-0.13% P, 1.28-1.63% K, 2.12-3.12% Ca, 0.32-0.53% Mg, ppm Fe, 41.7-76.3 ppm Mn, 6.1-10.3 ppm Cu, 21.3-28.5 Zn.
Mosambi sweet orange: Optimum leaf nutrient standards for ‘Mosambi’ sweet orange: 1.98-2.57% N, 0.091-0.17% P, 1.33-1.72% K, 1.73-2.98% Ca, 0.32-0.69% Mg, 69.5-137.1 132 ppm Fe, 42.2-87.0 ppm Mn, 6.6-15.8 ppm Cu, 11.6-28.7 ppm Zn, 12.8-23.1ppm B, and 0.39-1.1 ppm Mo.
Sathgudi sweet orange : Optimum leaf nutrient standards for ‘Sathgudi’ sweet orange : 2.01-2.42 % N, 0.09-0.12 % P, 1.12-1.82 %K, 1.93-2.73 % Ca, 0.36-0.53 % Mg, 53.5-82.1 ppm Fe, 48.7-79.3 ppm Mn, 3.7-8.9 ppm Cu, 16.5-23.2 ppm Zn, 12.8-23.1ppm B, and 0.39-1.1 ppm Mo.
Malta sweet orange : Optimum leaf nutrient standards for ‘Malta’ sweet orange: 2.14-2.31 % N, 0.10-0.14 % P, 1.10-1.56 % K, 2.89-3.41 % Ca, 0.39-0.52 % Mg, 42.6 – 81.4 ppm Fe, 28.1 – 54.3 ppm Mn, 4.2-8.9 ppm Cu, 28.1-54.3 ppm Zn.
Acid lime : Optimum leaf nutrient standards for Acid lime: 1.80-2.12% N, 0.09-0.13% P, 0.79-1.43%K, 2.04-3.12% Ca, 0.28-0.46 % Mg, 38.4-98.3 ppm Fe, 28.1-58.4 ppm Mn, 6.1-9.9 ppm Cu, 16.9-21.4 ppm Zn.

1.1.2 Soil Fertility Norms: The soil test method rests on the assumptions that roots would extract nutrients from the soil in a manner comparable to chemical soil extractants, and that there is a simple direct relation between the extractable concentration of nutrients in the soil and uptake by plants. This is based on the concept that an ideal soil is one where the cations are present in ideal proportions. One serious defect of this approach, is that it has to be significantly modified in relation to soil type, in particular as between calcareous and non-calcareous soils. Besides adjusting the recommendations in relation to targetted yield. Otherwise, soil nutrient depletion has grave implications in terms of : i. more acute nutrient deficiencies, ii. two wide spread nutrient deficiencies, iii. fall in fertilizer use efficiencies and in returns from fertilization, iv. weakening the foundation of sustainable high yield and v. very high remedial cost involved in building up the depleted soils. Differential soil fertility norms were obtained in relation to commercial citrus cultivars are briefly summarised below
:Nagpur mandarin : Optimum soil fertility limit was observed as : Alkaline KMNO4- N 118.4-1321.2 mgkg-1, Olsen-P 9.2-10.3 mg kg-1, NH4OAc-K 178.4-232.5 mg kg-1, DTPA-Fe 12.4-16.2 mg kg-1, DTPA-Mn 8.6-12.2 mg kg-1, DTPA-Cu 2.1-2.3 mg kg-1 and DTPA-Zn 0.98-1.1 mg kg-1 in relation to fruit yield of 39.7-54.1 kg tree-1.
Khasi mandarin : Optimum soil fertility limit was observed as : Alkaline KMnO4-N 220.8-240.6 mg kg-1, Bray-P 6.2-7.8 mg kg-1, NH4OAc-K 252.2-300.8 mg kg-1, DTPA-Fe 82.2-114.6 mg kg-1, DTPA-Mn 21.4-32.8 mg kg-1, DTPA-Cu 0.82-1.62 mg kg-1, and DTPA-Zn 2.18-4.22 mg kg-1 for an optimum fruit yield of 25.0-32.0 kg tree-1.
Kinnow mandarin : Optimum soil fertility limit was observed as : Alkaline KMnO4 -N 118.2-128.4 mg kg-1, Olsen-P 9.4-16.3 kg-1, NH4OAc- K 158.3-208.2 mg kg-1, DTPA-Fe 3.1-9.3 mg kg-1, DTPA-Mn 4.8-7.3 mg kg-1, DTPA-Cu 0.58-1.25 mg kg-1, DTPA-Zn 0.64- 0.98 mg kg-1 for the fruit yield of 61.8-140.3 kg tree-1.
Mosambi sweet orange : Optimum soil fertility limit was observed as : Alkaline KMnO4 -N 130.1-142.2 mg kg-1, Olsen-P 9.8-11.4 kg-1, NH4OAc- K 182.4-210.3 mg kg-1, DTPA-Fe 13.2-18.6 mg kg-1, DTPA-Mn 14.6-22.6 mg kg-1, DTPA-Cu 2.16-2.42 mg kg-1, DTPA-Zn 0.98-1.21 mg kg-1, hot water soluble-B 0.28-0.48 mg kg-1, and (NH4)2 C2O4-Mo 0.08-0.10 mg kg-1 for the fruit yield of 79.4-93.9 kg tree-1.
Sathgudi sweet orange : Optimum soil fertility limit was observed as : Alkaline KMnO4 -N 120.1-152.2 mg kg-1, Olsen-P 10.1-12.3 mgkg-1, NH4OAc- K 162.3-206.4, DTPA-Fe 11.2-16.4 mg kg-1, DTPA-Mn 10.1-18.3 mg kg-1, DTPA-Cu 2.2-3.6 mg kg-1, DTPA-Zn 0.54-1.10 mg kg-1.
Malta sweet orange: Optimum soil fertility limit was observed as : Alkaline KMnO4 -N 110.5-124.6 mg kg-1, Olsen-P 9.2-14.6 mgkg-1, NH4OAc- K 131.6-181.2, DTPA-Fe 9.8-14.2 mg kg-1, DTPA-Mn 6.9-9.2 mg kg-1, DTPA-Cu 0.82-1.10 mg kg-1, DTPA-Zn 0.81-0.96 mg kg-1 for fruit yield of 23.1-38.9 kg tree-1.
Acid lime: Optimum soil fertility limit was observed as : Alkaline KMnO4 -N 106.3-118.2 mg kg-1, Olsen-P 9.2-14.6 mgkg-1, NH4OAc- K 102.4-146.6, DTPA-Fe 4.6-12.3 mg kg-1, DTPA-Mn 3.2-10.1 mg kg-1, DTPA-Cu 0.80-1.40 mg kg-1, DTPA-Zn 0.78-0.89 mg kg-1 for fruit yield of 22.0-41.2 kg tree-1.

1.1.3 Dicision Support For Soil Test-Based Fertilizers Recommendations:Nutrient mining- induced multiple nutrient deficiencies is a common feature of commercial citrus belt of India. Nutrient constraints in citrus orchards are conventionally diagnosed using a variety of diagnostic tools viz., leaf analysis, soil analysis, biochemical analysis, juice analysis and of late flower analysis, with certain merits and demerits of each of the diagnostic tools. However, none of these diagnostic tools, alone is capable in indentifying the nutrient constraints precisely. Leaf analysis is widely used in indentifying the aoccurrence of different nutrient constraints of late, these has been renewed efforts to refined soil fertility testing for fertilizers recommendations for variety of annual as well perennial crops, with citrus no exception . unfortunately ,there is hardly soil test – crop response model have been developed in any of the fruit crops , which can precisely recommend fertilizers application based on given soil test value and in anticipation with large yield this is first attempt of this kind in any of the fruit crops grown in India, by exploiting the Diagnosis and Recommendation Inintegrated system and geospatae tools (GEO- referenced grand based soil sampling and geographical information system.

1.1.4 Soil Suitability Criteria: Ideally, there are three basic requirements for successful cultivation of any horticultural crop, namely, climate relatively free from frost, good quality of irrigation water and a reasonably deep uniform fertile soil with good internal drainage. Consequences of poor soil type can often be tailored through efficient use of irrigation, drainage and soil amendments. More often than not, such modifications of the soil and its environment are made to assist crop growth and survival in addition to increased nutrient uptake efficiency, a secondary consideration. Horticulture crops over the years, have displayed some extraordinary success on great variety of soils.

Mandarins (Citrus reticulata Blanco)Sweet oranges(Citrus sinensis Osbeck)
Acid lime
NutrientsNagpur mandarinKinnow* mandarinKhasi mandarinMosambi
sweet orange
Malta sweet orange(Citrus aurantifolia Swingle)
Soil test- based diagnostics
N (mg kg-1)94.8 –154.8114.3-121.2161.0- 418.7107.4-197.2120.1-152.2110.5-124.6106.3-118.2
P (mg kg-1)6.6 – 15.97.8-12.34.5 – 8.78.6-15.810.1-12.39.2-14.69.2-14.6
K (mg kg-1)146.8 –311.996.4-131.382.3 -287.5186.4-389.2162.3-206.4131.6-181.2102.4-146.6
Ca (mg kg-1)408.1 616.089.4-248.6148.8- 285.4512.1-728.4582.3-812.2210.6-294.3210.3-318.7
Mg (mg kg-1)85.2-163.272.3-89.631.3 – 84.4119.4-182.3123.8-198.772.9-94.689.6-106.3
Fe (mg kg-1)10.9-25.25.8-11.139.5 – 180.91.76-4.7011.2-16.49.8-14.24.6-12.3
Mn (mg kg-1)7.5- 23.24.3-6.927.0 – 80.30.44-1.0310.1-18.36.9-9.23.2-10.1
Cu (mg kg-1)2.5 – 5.10.45-0.690.67 – 2.900.31-0.572.2-3.60.82-1.100.80-1.40
Zn (mg kg-1)0.59 – 1.260.62-0.782.84 – 5.140.09-0.160.54-1.100.81-0.960.78-0.89
Yield (kg tree-1)47.7 –117.232.8-56.231.6 – 56.376.6-137.982.9-158.223.1-38.922.0-41.2
Leaf analysis-based diagnostics
N (%)1.70 – 2.812.22-2.321.97 –2.561.98-2.572.01-2.422.14-2.311.53-2.10
P (%)0.09 – 0.150.11-0.150.09 – 0.100.091-0.171.12-1.820.10-0.140.10-0.15
K (%)1.02 – 2.591.10-1.410.99 – 1.931.33-1.721.93-2.731.10-1.560.96-1.66
Ca (%)1.80 – 3.282.32-2.791.97 – 2.491.73-2.980.36-0.532.89-3.413.05-3.43
Mg (%)0.43 – 0.920.38-0.610.24 – 0.480.32-0.6953.5-82.10.39-0.520.40-0.60
Fe (ppm)74.9 – 113.422.4-58.384.6 – 249.069.5-137.148.7-79.342.6-81.40.25-0.29
Mn (ppm)54.8 – 84.626.3 -56.241.6 – 87.642.2-87.03.7-8.928.1-54.3117-194
Cu (ppm)9.8 – 17.64.2-7.22.13 – 14.46.6-15.816.5-23.24.2-8.921-63
Zn (ppm)13.6 – 29.621.3-26.916.3 – 26.611.6-28.712.8-23.121.3-26.98.68-14.8
Yield(kg/tree)47.7 – 117.232.4-56.131.6 – 56.376.6-137.982.9-158.223.1-38.956.4-70.0

Soil N
(kg ha-1)
P- Recommendation
Soil P
(kg ha-1)
K – Recommendation
Soil K
(kg ha-1)

Ready reckoner for soil test-based fertilizer recommendation at various targeted fruit yield levels of Nagpur mandarinAnd resultantly, development of distinct commercial belts (Production epicenters) of mango, grapes, citrus, pomegranate, banana, litchi, apple, seed spices/spices, coconut, tea/coffee, pineapple, potato, onion have emerged as major success stories of Indian Horticulture. Their huge success along these commercial belts needs to be analysed from the perceptive of role of nature and properties of different soils in order to ensure their continued sustenance.


Soil suitability criteria for Nagpur mandarin (Citrus reticulate Blanco) and sweet orange cultivar Mosambi grown in Marathwada region of Maharashtra

SoilNagpur MandarinMosambi Sweet orange
Soil pH7.6-7.87.9-8.07.4-7.97.6-8.1
Soil EC (dS m-1)0.12-0.240.21-0.280.22-0.340.26-0.44
Free CaCO3 (%)11.4-12.815.6-18.211.2-14.912.6-16.8
Particle size distribution (%)
Water soluble cations (mg l-1)
Exchangeable cations [cmol(p+) kg-1]
Fertility status (mg kg-1)
Available N118.4-121.292.8-110.2130.1-142.2120.4-128.6
Available P9.2-10.37.2-8.09.8-11.49.2-10.8
Available K178.4-232.5204.2-228.1182.4-210.3192.2-222.2
Available Fe12.4-16.210.6-12.313.2-18.611.2-18.9
Available Mn8.6-12.27.2-9.114.6-22.615.2-21.8
Available Cu2.1-2.31.0-1.22.16-2.422.10-2.56
Available Zn0.98-1.100.72-0.780.98-1.210.81-0.92
Yield (Tons ha‑1)11-157-1024.1-26.211.8-12.3

1.1.5 Deficiency Symptoms
Like any other perennial fruit crop, citrus is a heavy forager of nutrients and, therefore, highly responsive to applied fertilizers. Nutrient mining emerging due to widening gap between the amounts of nutrients applied and to those removed, amount to occurrence of large scale nutrient deficiencies. A variety of nutrient constraints diagnostic methods are used in citrus orchards. Those comprise of leaf analysis, soil analysis, juice analysis, sap analysis, biochemical analysis, and morphological symptoms-linked deficiency symptoms. Of them, use of morphological symptoms acts as a field manual for citrus growers who can easily identify the nutritional problems in their orchards and adapt the corrective measures accordingly.The nutrient deficiency symptoms appear on different plant parts, most frequently on leaves, fruits and roots, in addition to types of leaves depending upon nature and properties of different nutrient elements. The symptoms on fruits are noticed for very immobile nutrients like B and Ca. Development of visible symptoms is accountable to metabolic disorders which cause changes in micro-morphology of plants before these symptoms are identifiable. The way in which the symptoms develop and manifest on younger or older leaves or the fruits, gives a reliable indication about the cause of nutritional disorders. Both deficiency and excess of nutrients can lead to reduction in crop yield coupled with inferior fruit quality. Mild visible leaf symptoms of some of the essential element deficiencies can be tolerated without a reduction in yield in some citrus varieties, but not in others. For example, sweet orange trees can withstand the mild foliage symptoms of Zn-deficiency without a loss in yield, while the lemon trees suffer the heavy yield loss.

1.2 Management of Nutrient Constraints: Nutrient management-based production system of citrus like any other fruit crop is inherently complex to understand due to large variation in nutrient-use-efficiency. Citrus is considered evergreen in nature, blessed with nutrient conservation mechanism, to facilitate an increased carbon return per unit of invested nutrient due to comparatively longer duration of photosynthesis eventually leading to higher nutrient-use-efficiency. 4R-nutrient management concept, exploiting criteria of right choice of fertilizers at right dose at right stage of right crop has been the most pivotal driving force towards improved nutrient-use-efficiency. However, citrus by the virtue of their perennial nature of woody framework (Nutrients locked therein), extended physiological stages of growth, differential root distribution pattern (root volume distribution), growth stages from the point of view of nutrient requirement and preferential requirement of some nutrients by specific fruit crop, collectively make them nutritionally more efficient than the annual crops. This is the reason, it is considered as such a wholesome concept.

1.2.1 Inorganic Fertilizer Scheduling: Soil provides nearly all the nutrients essential to complete the life cycle of a plant. Different soil properties primarily determine the extent of a fertilizer response and the crop rotation on some recently published review articles changes in physico-chemical and biological properties of soil. One of the major obstacles of conventional practices of addressing nutritional requirements of citrus either through soil fertilization or through foliar feeding, is the precise diagnosis if the nutrient constraint type, their doses as per crop age and soil type, with the result more often such practices have not been able to facilitate the realisation of potential productivity of citrus. Neither any due consideration is given to exploit the nutrient reserve of the plant’s rhizosphere (native nutrient supplying capacity of soil) while formulating the fertilizer doses. And most importantly in perennial fruit crops, nutrient doses need to be recommended in tandem with level of fruit yield targeted, a nutrient dose optimum for one fruit yield target will become suboptimum for higher targeted fruit yield level in couple in subsequent years. Where is such nutrient monitoring tool to keep vigil on nutrient input and output relationship, a kind of nutrient budgeting.

1.2.2 Citrus-based Microbial Consortium for Better Nutrient-Use-Efficiency vis-a-vis Carbon Sequestration :Exploiting microbial synergisms is one of the popular methods of substrate dynamics and associated changes in nutrient environment of rhizosphere as a part of rhizosphere engineering. Formation of associations with other organisms to promote protection from potentially inhibitory environmental factors where such associations reflect synergistic lifestyles facilitating more effective and efficient growth and biogeochemical cycles than individual populations as a community. Such associations are often called microbial consortium in which members of the consortium maintain metabolic and ecological compatibility for individual niches to exist in the close proximity in soil. Such microbial consortium is more resistant to environmental changes, and can compete much better than single micro-organism. When different microbial strains are made into an inoculum consortium, each of the constituent stains of the consortium not only out-compete with others for rhizosphere establishments, but complement functionally for plant growth promotion.Different microbial components in a microbial consortium should possess: i. high rhizosphere competence, ii. high competitive saprophytic ability, iii. ease for mass multiplication, iv. safe to environment, v. broad spectrum of action, vi. excellent and reliable efficacy, vii. compatible with other rhizosphere microbes, and in able to tolerate other abiotic stresses, viii. strong compatibility with inorganic fertilizers and different organic manures.Very limited efforts have been made in citrus using these directions, which is so important from nutrient conservation point of view (Safeguarding both indigenously available and externally applied) to have complete stock of nutrient budgeting in an orchard. Such attempts will serve dual purpose, improve soil and plant resilience and offer ecological service through effective orchard floor management.
The microbial diversity existing within rhizosphere soil from high yielding citrus orchards was characterized and isolated the promising microbes viz., Micrococcus yunnanensis (Asymbiotic N-fixer), Bacillus pseudomycoides (Silicate-solubilizer), Paenibacillus alvei (P-solubilizer), Acinetobacter radioresistens (P-solubilizer) , Aspergillus flavus (P-solubilizer). Pure culture of these microbes in value added form (108-1010 cfu mL-1) was developed in broth, and prepared a mixture called microbial consortium. The microbial activity of all the five component microbes was further followed as 15 days interval upto 60 days of storage to find out the shelf life of such microbial consortium. Microbial activity of consortium remained active upto 60 days.
Biometric Response of Microbial Consortium : The response of microbial consortium on rough lemon seedlings showed a significant increase in various growth parameters (9.59 g root weight, 24.86 g shoot weight, and 11.9 mm stem diameter) over control (2.99 g root weight, 9.08 g shoot weight, and 8.6 mm stem diameter) on per plant basis. Similar observations were made on buddlings also. There was a significantly higher growth with microbial consortium treated buddlings (11.76 g root weight, 26.41 g shoot weight, and 28.51 mm stem diameter on per plant basis) compared to untreated control (4.10 g root weight, 10.72 g shoot weight, and 20.20 mm stem diameter). Same microbial consortium in combination of 50% inorganic fertilizers + 50% vermicompost) produced a much better quantitative as well as qualitative response compared to treatment without microbial consortium in bearing Nagpur mandarin orchard. Such an attempt has an excellent potential for carbon accreditation as a climate resilient option, against potential soil health deterioration.

1.2.3 Integrated Nutrient Management: Citrus, by its avid nutrient absorbing capacity is considered highly nutrient responsive perennial fruit crop. Differential efficacy of two conventional methods of fertilization (soil versus foliar application) has, although helped in improving the quality citrus, but of late, continuous fertilization has failed to sustain the same yield expectancy on a long term basis due to depletion of soil carbon stock and consequently, emerged multiple nutrient deficiencies, irrespective of soil type. The menace of multiple nutrient deficiencies would be further triggered through increase in air temperature via changes in microbial communities and activities within the rhizosphere in the light of climate change. Such changes will dictate adversely on the orchard’s productive life in long run. Gradual shift from purely inorganic to organic fertilizers started gaining wide scale use for enhanced biogeochemical nutrient cycling. Long term data accrued on response of organic manuring versus inorganic fertilizers demonstrated that important soil quality indices like soil microbial diversity, soil microbial biomass nutrient (Cmic, Pmic, and Nmic) and organic carbon partitioning displayed significant changes, but without much difference in quantum of fruit yield. The other approaches involving multiple microbial inoculation along with enrichment of organic manures through inorganic fertilizers known as substrate have further been highlighted as a part of INM module to provide an understanding on mechanism involved in C stabilization in soils for regulating soil C sequestration and associated nutrient dynamics under INM–based production system in citrus orchards. Integration of such microbial consortium with organic manures and chemical fertilizers (basis for INM–based nutrient management) in addition to concepts like sensor based–programmable fertigation and precision oriented site specific nutrient management exploiting spatial variation in soil fertility and leaf nutrient composition could further provide the much desired niche in the production sustainability through engineering nutrient dynamics within the rhizosphere under changing climatic scenario.
INM- Schedule recommended for Ambia and Mrig crop of Nagpur mandarin

Components of INMAmbia cropMrig crop
Soil application
Vermicompost (kg)
Inorganic fertilizers (g/tree)300g urea300g urea
260g SSP260g SSP
110g MOP110g MOP
Microbial consortium (ml/plant)
Foliar spray Month of spray
0.50% FeSO4+ 0.50% MnSO4******
0.50% ZnSO4******
0.25% Borax******

FeSO4 (0.50%) to be prepared by dissolving 500g FeSO4 in 100 L water;MnSO4 (0.50%) to be prepared by dissolving 500g MnSO4 in 100 L water;ZnSO4 (0.50%) to be prepared by dissolving 500g ZnSO4 in 100 L water;Borax (0.25%) to be prepared by dissolving 250g borax in 100 L water.
1.3 Organic Management Module in Nagpur Mandarin
The application of vermicompost loaded with microbial consortium (100% N- equivalent basis) + IPM2 ( foliar application of Horticulture Minieral oil (2%) followed by Beauveria bassiana @ 5g/1 and Azadirachtin (1%) @ 4 ml/1) + IDM1 – Bordeaux paste (CuSO4 : Lime: Water = 1:1:10) as pre monsoon /post monsoon trunk application along with Trichoderma harzianum native antagonistic strain , NRCfBA29 (100g/ plant) with carrier material of FYM (1kg) as soil application at root zone recorded maximum production and productivity coupled with soil health. the comparative economics of conventional and oraganic production of Nagpur mandarin further demonstrated an additional income of Rs 1,57,954/- hectare through organic production of Nagpur mandarin.
Comparison of cost of cultivation of conventional versus organic production of Nagpur Mandarin (Input cost calculated on a hectare basis in Indian rupees)
Conventional ManagementOrganic Management
Nutrient Management (Fertilizers)Nutrient Management (vermicomposting loaded with microbial consortium)
Insect pests Management (Insecticides)Insect pests Management (Botanicals)
Disease Management (Fungicides)Disease Management (Trichoderma / Bordeaux paste)
Bamboo StakesBamboo Stakes
Drip IrrigationDrip Irrigation
Total costTotal cost
Gross Return through yield 17.0 tons/ha, 2,89,000=00Gross Return through yield 23.4 tons/ha, 4,45,680=00
Net return/ haNet return/ ha

Higher net return by organic cultivation over conventional production was observed as 1, 57,954=00/ ha.