Better Crops/Vol. 95 (2011, No. 1) 7 O/ 2 3.53 3.84 2.82 3.08 2.70 3.56 3.11 3.65 0.15 3.12 4.00 2.91 2.84 3.01 3.02 3.30 3.68 Mean 3.98 2.92 3.16 2.60 3.80 3.04 3.46 3.80 0.18 3.06 4.19 3.01 2.76 3.04 2.94 3.50 3.96 2008-09 3.70 2.72 3.00 2.80 3.32 3.18 3.60 3.50 0.12 3.18 3.91 2.81 2.92 2.98 3.10 3.10 3.40 - - - - - Bulb yield, t/ha - - - - - 2007-08 - onion bulb yield (fresh weight basis). weight onion bulb yield (fresh /ha by Bray’s method), and low available K (178 kg K kg (178 K available low and method), Bray’s by /ha 5 outlines 16 treatments that were replicated three replicated were that treatments 16 outlines 1 Table = 75% RDF + PSB = 50% RDF + 50% Vm = 50% RDF + Az = 50% RDF + Azr = 75% RDF + Az = 50% RDF + PSB = 75% RDF + Azr = Control = Current (RDF) recommendation (PiM) = Pig manure (Vm) = Vermicompost = 50% RDF + 50% PiM = FYM = Poultry (PM) manure = 50% RDF + 50% FYM = 50% RDF + 50% PM O 15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Response of different on the 1. Response INM-based treatments Table 2 T T T T Treatments T T T T CD (p = 0.05) T T T T T T T T ha, ammonium acetate extractable) (Sparks, 1996). and Black method), low available N (248 kg/ha by alkaline permanganate distillation method), low available P (11 P kg of inorganic fertilizersCombined application of inorganic offers manures organic with in India. in onion production results better -

nion (Allium cepa L) is a highly nutrient-responsive crop. Conventional methods of fertilization have un- doubtedly helped in improving both bulb yield and

The experiment was conducted during the kharif (mon- This field experiment was carried out with two major ob- Although the use of manures as nutrient sources for veg- Abbreviations: N = nitrogen; P = phosphorus; K recommended = RDF chloride; potassium = KCl superphosphate; single = potassium; SSP = = PM manure; pig = PiM manure; farmyard = FYM fertilization; of dose poultry manure; Vm = vermicompost; CD = critical difference, equiva- = 1 USD Note: rupee. Indian = INR Difference. Significant Least to lent approximately INR 44.1.

O Onion Production Systems ProductionOnion Systems source. nutrient either of application sole over manures and fertilizers inorganic of tion inoculant microbial any plus recommendation fertilizer the of 75% to 50 of Application viable alternative. a treatment failed to achieve Studies Studies evaluated straight versus combined applications of manures, fertilizers, and microbial biofertilizers with reference to onion bulb yield applica and combined soil nutrient the balances. favored observations manures, quality of supply good the Given By Ethel Ngullie, V.B. Singh, A.K. Singh, and Harmandeep Singh A.K. Singh, and Harmandeep Singh, V.B. By Ethel Ngullie, Fertilizing for SustainableFertilizing for INDIA soon) seasons between 2007-09 at theSchool the of longitude) E 93°53’04” - latitude N (25°45’43” experimental farm of Agricultural Sciences and Rural Development (SASRD), Nagaland Medziphema, University, Nagaland to study fertil- ization strategies for sustainable onion (var. Typic Agrifound Dark as classified was soil experimental The production. Red) 21% and silt, 20% sand, (58% texture loam a with Rhodustalf Walkley by g/kg (21.8 carbon organic high (1:2), 5.2 pH clay), jectives: 1) determine the magnitude and economic value of the assess 2) and treatments, INM-based to onion of responses nutrient uptake pattern to determine net changes in the soil nutrient balance sheet. etables is common, their effectiveness is potentially limited by by limited potentially is effectiveness their common, is etables distri nutrient release patterns that are often out field of synchrony with and quality source in variability large demand, crop to contributed have issues these of All safety. food and bution, from shift gradual A options. alternative with experimentation using purely organic sources to introducing some proportion has shift This acceptance. gaining is fertilization inorganic of formed the basis for INM, which could involve three nutrient sources: microbial inoculants or biofertilizers including azo- tobacter (Az), azospirillum (Azr), and phosphate solubilizing bacteria (PSB), inorganic fertilizers, and manures. However, INM further prescribes that selected nutrient inputs be used nutrients essential all of supply optimum ensure to judiciously for sustained crop production. Most INM studies required conducted components experimental the lacked have onion with to link soil nutrient budgeting with bulb yield response. quality. But lately, routine management practices in India ap- India in practices management routine lately, But quality. long-term. the over yields maintaining of incapable be to pear occurrence the and fertility soil native of depletion steady The the to led has fields onion in deficiencies nutrient multiple of limiting factor key a as management nutrient of identification Integrated 2003). al., et (Sharma production onion sustainable (Dimri strategy effective an offers (INM) management nutrient and Singh, 2005; Santhi et al., 2005). Table 2. Balance sheet for nutrient input and output for onion in response to INM treatments (mean of two seasons).

Nutrient addition, kg/ha Nutrient removal, kg/ha Net balance, kg/ha N P O K O N P O K O N P O K O Treatments 2 5 2 2 5 2 2 5 2 1 T1 = Control - - - 45 (1.68) 25.2 (0.40) 32.4 (0.98) -45 -25 -32

T2 = Current recommendation (RDF) 100 60 60 79 (2.22) 45.8 (0.57) 52.8 (1.24) 21 14 7

T3 = FYM 104 23 162 56 (1.86) 29.8 (0.44) 37.2 (1.02) 48 -7 125

T4 = Pig manure (PiM) 109 18 95 61 (1.96) 36.6 (0.50) 44.4 (1.20) 48 -19 51

T5 = Poultry manure (PM) 107 25 91 63 (1.90) 34.3 (0.44) 49.2 (1.12) 44 -9 42

T6 = Vermicompost (Vm) 102 18 74 75 (2.12) 41.2 (0.50) 48.0 (1.14) 27 -23 26

T7 = 50% RDF + 50% FYM 106 72 141 74 (1.92) 41.2 (0.46) 50.4 (1.10) 32 31 91

T8 = 50% RDF + 50% PiM 105 70 108 74 (2.02) 43.5 (0.51) 54.0 (1.24) 31 26 54

T9 = 50% RDF + 50% PM 104 69 97 73 (1.98) 41.2 (0.48) 51.6 (1.16) 31 27 46

T10 = 50% RDF + 50% Vm 101 73 106 96 (2.40) 52.7 (0.58) 64.8 (1.34) 5 20 41

T11 = 50% RDF + Az 70 69 36 51 (1.76) 29.8 (0.44) 36.0 (1.02) 19 39 0

T12 = 50% RDF + Azr 75 69 36 49 (1.72) 27.5 (0.43) 50.4 (1.88) 26 42 -14

T13 = 50% RDF + PSB 50 114 36 50 (1.78) 29.8 (0.46) 37.2 (1.11) 0 84 -1

T14 = 75% RDF + Az 95 69 36 55 (1.82) 32.1 (0.46) 40.8 (1.14) 40 37 -5

T15 = 75% RDF + Azr 100 69 36 56 (1.83) 34.3 (0.48) 43.2 (1.18) 44 35 -7

T16 = 75% RDF + PSB 75 114 36 57 (1.84) 34.3 (0.49) 67.2 (0.18) 18 80 -31 CD (p = 0.05) - - - 5.4 (0.12) 2.5 (0.03) 4.6 (0.16) - - - 1Figures in parentheses represent nutrient concentration in % (expressed on elemental basis). times and tested in a randomized complete block design. Full color method, and K by flame photometer (Page et al., 1982). rates for the FYM (0.8% N, 0.08% P, 1.04% K), PiM (1.82% Nutrient budgets were calculated on the basis of nutrient inputs N, 0.14% P, 1.32% K), PM (2.14% N, 0.22% P, 1.52% K), minus nutrient removal by onion bulbs. and Vm (2.04% N, 0.15% P, 1.24% K) were designed to sup- Treatments supplying inorganic fertilizers and organic ma- ply approximately the same N (100 kg N/ha) provided by the nures, either alone or in combination, generated a significant RDF treatment and were calculated to be 13 t, 6 t, 5 t, and 5 t/ bulb yield response in both seasons over the control (Table ha, respectively. The combined manure + fertilizer treatments were also designed to supply approximately 100 kg N/ha. In- organic fertilizers sources were urea, single superphosphate (SSP), and potassium chloride (KCl). The anticipated nutrient to be added through the Az, Azr, and PSB biofertilizers was credited to the different treatments as 20 kg N, 25 kg N, and

20 kg P2O5/ha, respectively. Each treatment received its entire dose (rate) of manure each year at the time of land preparation. The full dose of P, K, and half dose of N were applied each year at the time of planting and the remaining half dose of N was applied 30 days after planting. For the biofertilizers, the bulblets were dipped in treatment slurries at the rate of 10 g/kg bulblets and then dried under shade before planting. Experimental plots were treated with Trichoderma to minimize the incidence of damping-off disease. The bulblets were planted on raised beds during the first week of September and harvested in first week of January in both the seasons. The bulbs were harvested after more than 50% of leaves dropped down, and bulb fresh weight was measured. The bulbs were dried in shade, then chopped off and dried at 63 °C ± 2 °C, finely ground, and samples were digested in a 3:1 di-acid

mixture of H2SO4 and HClO4. In these acid extracts, nutrients were determined as per standard procedures including N by steam distillation using the micro-Kjeldahl method, P by Scene at the National Research Center for Onion and Garlic in Pune,

Better Crops/Vol. 95 (2011, No. 1) Crops/Vol. Better colorimeter using the vanadomolybdophosphoric acid yellow India. 8 Better Crops/Vol. 95 (2011, No. 1) 9

47.76 60.92 59.60 55.36 51.50 37.20 64.86 52.44 50.06 48.66 62.96 61.66 46.00 40.40 52.14 50.56 Net return, Net 000’ INR/ha 5,000/ha 8/kg, KCl KCl 8/kg, INR INR 56.40 54.00 71.20 70.60 73.00 62.20 80.00 62.40 58.20 56.80 73.60 76.80 66.00 60.40 61.60 60.02 Benefit, 2 1/kg, Azr and Azo at 1/kg, 000’ INR/ha 20/kg. INR INR 5/kg, SSP at 5/kg, INR Cost, 1 10.28 11.00 17.64 25.00 15.94 10.64 15.14 20.00 20.00 9.96 9.46 8.64 2.50 9.46 8.14 8.14 000’ INR/ha 2/kg, FYM at 2/kg, 100/kg. It also includes operational charges charges It also includes operational 100/kg. INR BC INR 225-227. Society of America. Part Part 2: Chemical and Microbiological Properties. American USA. Society Madison, Wisconsin, Agronomy, of 39(3):213-216. 44.41). production (In order of highest net return). of highest order (In net production INR of considering the sustainability of onion productivity as well as productivity onion of sustainability the considering of regional on dependence strong a maintain to preference the as sources like FYM. Singh, R.P., N.K. Jain, and B.L. Poonia. 2001. Indian J. Agric. Sci. 71(5):310-312. Sci. Agric. J. Indian 2001. Poonia. B.L. and Jain, N.K. R.P., Singh, Sparks, D.L. 1996. Methods of soil analysis: Chemical methods. Soil Science Ms. Ngullie is Horticulture Consultant, Central Institute of Horticul- of Institute Central Consultant, Horticulture is Ngullie Ms. Rural and Sciences Agricultural of School University, Nagaland ture, kaka_ngl@ e-mail: Nagaland; Medziphema, (SASRD), Development Lecturer, Singh yahoo.com. is V.B. is Department Dr. Professor, of Horticulture, Singh A.K. Dr. Medziphema. University, Nagaland SASRD, Department of Agril. Chemistry & Soil Science, SASRD, Nagaland Harmandeep Medziphema. Singh Dr. is University, Deputy Director, Region; e-mail: [email protected]. West IPNI South Asia Program, References Hort. 37(1):185-187. Singh. 2005. Prog. and V.P. Dimri, D.C. of Analysis. Methods Soil 1982. (eds). Keeney D.R. and Miller, R.H. A.L., Page, Santhi, R., R. Natesan, and G. Selvakumari. 2005. Indian J. Agric. Datt, N. and Res. Pritam Sharma, Sharma. R.P., 2003. Agric.Indian J. Sci. 73(4): 40/kg, PiM, PM and Vm at 40/kg, 50/kg, and PSB cultures at and PSB cultures 50/kg, - - INR = 50% RDF + 50% Vm = 50% RDF = 75% RDF + PSB = 75% RDF + Az = 50% RDF + Az = 50% RDF + Azr = 75% RDF + Azr = 50% RDF + PSB = Current (RDF) recommendation (Vm) = Vermicompost = 50% RDF + 50% PiM = Control (PiM) = Pig manure = 50% RDF + 50% PM = 50% RDF = 50% RDF + 50% FYM = Poultry (PM) manure = FYM 10 9 7 2 6 8 16 15 1 14 11 12 13 5 3 4 Economics of different of 3. Economics Kharif for treatments INM-based onion Table Benefit of onion at based on minimum farm rate Cost based on price of treatments at of urea T at (USD 1 ≈ INR 2 T 1 T T T T T T T T covering labor charges for land preparation and two weedings at weedings and two land preparation for labor charges covering T T T T T T Treatments - . All 2). (Table 0.01), P (r = 0.612, p = 0.01), = p 0.612, = (r P 0.01), = . A comparison of the effect of O/ha. 2 -K 5 O 2 (Table 2) Nutrient removal under the RDF treatment was hard hard was treatment RDF the under removal Nutrient Economic analysis highlighted that sole reliance on ma- Onion growers in this region often prefer organic manur Considering the net nutrient balances presented, the to distinguish from that measured under any manure treatment their versus manures with fertilizers inorganic combining signifi- found biofertilizers selected with co-application compared former the with uptake nutrient higher cantly to the As latter. little as 25% of the RDF could not be replaced through biofertilizer supplementation, but up to 50% of the RDF could be effectively replaced with selected manures. The treatment with 50% RDF+Vm observed the highest average nutrient removal of 96- 53-65 kg N-P and K (r = 0.405, p = 0.05). Data averaged over the two the over averaged Data 0.05). = p 0.405, = (r K and able source manure only the be to VM revealed seasons to produce, by itself, bulb yields that were equivalent The best to bulb those yield under responses the RDF. were achieved with 50% RDF+Vm followed by 50% unable were biofertilizers contrary, the On RDF+FYM. inorganic of rates application reduced for 75% compensate to or 50% with along biofertilizers of use The fertilizer. RDF resulted in bulb yield averages that were at best and sources manure performing poorer the to equivalent in some cases were indistinguishable inorganic from the control. of rate reduced the of performance positive The fertilization plus either Vm or FYM does highlight the value of good manure sources as a supplement to inor ganic fertilizers. Mineralization of manures aids in soil nutrient improved to leads turn in that buildup nutrient al., 2001). availability to growing crop (Singh et ing over inorganic fertilization. As is the for indicated concern of cause major above, a be to suggested thisis preference supply good the Given imbalances. nutrient multiple of spread of quality manures, our observations favored the combined ap- sole over manures and fertilizers inorganic of application plication of either nutrient source. This is a strategy capable 1). Bulb yields were significantly correlated withbulb p 0.732, = (r N of uptake nures is not a cost-cutting measure, but favorable changes in hectare per costs additional for compensate likely quality soil through improved long-term nutrient turnover due to the or current inorganic fertilization recommendation maintained a study of years 2 over nutrients of stock surplus treatments the while deficits, P developed treatments manure with 50 to 75% RDF treatments used in combination biofertilizers with generated small to moderate K deficits.Treat- ments providing inorganic fertilizers and manure resulted in nutrients. no deficit for any of the three primary further treatment per returns net However, amendments. ganic fertilizer/manure combined any of superiority the substantiated application compared to a fertilizer or manure application at . 3) the rates examined (Table