Dept of Soil Science and Agricultural Chemistry-Technologies Developed

Research

Technologies Developed/ Salient findings

1. STCR –IPNS Technologies

• Soil test and yield target based fertilizer prescriptions under Integrated Plant Nutrition System (STCR-IPNS) have been developed for 31 agricultural and horticultural crops and 10 major cropping sequences on 17 soil series covering six agroclimatic zones of Tamil Nadu. These fertilizer prescriptions can be adopted with recommended secondary and micronutrients  along with the entire improved package of practices for various crops in similar and allied soil types occurring in different agro climatic zones of  Tamil Nadu.

STCR –IPNS Technology for Various Crops and Soils of Tamil Nadu

Fertiliser Prescription Equations (with FYM)
Crop/Variety	Soil		Prescription Equation	Applicable Districts
1.Rice – Kharif (short duration varieties)	Sandy  loam to clay loam River alluvium (Noyyal series)		FN = 4.39 T – 0.52 SN – 0.80 ON FP2O5 = 2.22 T – 3.63 SP  – 0.98 OP FK2O = 2.44 T – 0.39 SK – 0.72 OK	Coimbatore, Tiruppur and Vellore
2.Rice – Rabi (medium & long duration varieties)	Sandy  loam to clay loam River alluvium (Noyyal series)		FN = 4.63 T – 0.56  SN – 0.90 ON FP2O5 = 1.98 T – 3.18  SP-  0.99  OP FK2O = 2.57 T – 0.42  SK – 0.67 OK	Coimbatore, Tiruppur and Vellore
3.Rice (SRI)-kharif  (short duration varieties)	Sandy  loam to clay loam River alluvium (Noyyal series)		FN = 4.33 T – 0.53 SN – 0.68 ON FP2O5 = 2.08 T – 3.18 SP – 0.70  OP FK2O = 2.78 T – 0.30 SK – 0.63 OK	Coimbatore, Tiruppur and Vellore
4.Rice(SRI)- Rabi (medium & Long duration varieties)	Sandy  loam to clay loam River alluvium (Noyyal series)		FN = 4.20 T – 0.45 SP – 0.68 ON FP2O5 = 2.05 T – 2.65 SP – 0.66 OP FK2O = 2.85 T – 0.29 SK – 0.59 OK	Coimbatore, Tiruppur and Vellore
5.Rice (SRI)-Rabi (var. White Ponni)	Sandy  loam to clay loam River alluvium (Noyyal series)		FN = 3.43T – 0.34 SN – 0.64 ON FP2O5 = 1.83T – 3.24 SP – 0.61  OP FK2O = 1.98T – 0.18 SK – 0.37 OK	Coimbatore, Tiruppur and Vellore
6.Rice – Kharif (short duration varieties)	Red sandy loam (Irugur series)		FN = 5.19 T – 0.89  SN -0.98 ON FP2O5 = 2.27 T – 4.50  SP -1.09  OP FK2O = 3.11 T –  0.59 SK -1.02 OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore and Thiruvallur.
7.Rice – Rabi (medium & long duration varieties)	Red sandy loam (Irugur series)		FN = 4.88 T – 0.68 SN – 0.72 ON FP2O5 = 2.06 T – 2.91 SP – 2.27 OP FK2O = 2.89 T – 0.47 SK – 0.59 OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore and Thiruvallur.
8.Rice – Rabi (medium & long duration varieties)	Clay loam Black alluvium (Adanur series)		FN = 2.80 T- 0.29 SN – 0.89 ON FP2O5 = 1.35 T – 1.28 SP – 1.78 OP FK2O = 2.50 T – 0.42 SK -1.14 OK	Thanjavur, Tiruvarur, Nagapattinam, Tiruchirappalli, Karur, and Cuddalore.
9.Rice – Kharif (short duration varieties)	Clay loam Black alluvium (Kalathur series)		FN = 5.29 T – 0.75 SN – 0.89 ON FP2O5 = 1.65 T – 1.76 SP – 0.78  OP FK2O = 2.73 T – 0.37 SK- 0.82  OK	Thanjavur, Tiruvarur, Nagapattinam, Tiruchirappalli,Madurai, Perambalur and Ariyalur.
10.Rice-Rabi (medium & long duration varieties)	Clay loam Black alluvium (Kalathur series)		FN = 5.34 T – 0.67  SN – 0.73 ON FP2O5 = 1.90 T – 1.86  SP – 0.70 OP FK2O = 2.81 T – 0.33  SK – 0.80 OK	Thanjavur, Tiruvarur, Nagapattinam, Tiruchirappalli, Madurai, Perambalur and Ariyalur.
11.Rice – Kharif (short duration varieties)	Sandy clay loam River alluvium (Manakkarai series)		FN = 4.25 T – 0.60 SN – 0.79 ON FP2O5 = 2.71 T – 4.39 SP – 0.89 OP FK2O = 3.83 T – 0.60 SK – 0.82 OK	Tirunelveli, Thoothukudi and Thiruvallur.
12.Rice – Rabi (medium & long duration varieties)	Sandy clay loam River alluvium (Manakkarai series)		FN = 4.47 T – 0.58 SN – 0.79 ON FP2O5 = 2.66 T – 3.68 SP – 0.89 OP FK2O = 4.08 T – 0.65 SK – 0.82 OK	Tirunelveli, Thoothukudi and Thiruvallur.
13.Rice (SRI)- Rabi (medium & long duration varieties)	Sandy clay River alluvium (Ambasamudram series)		FN = 3.54 T- 0.30 SN – 0.94 ON FP2O5 = 1.37 T-  0.41 SP – 0.80 OP FK2O = 2.61 T- 0.64 SK – 0.61 OK	Tirunelveli,Thoothukudi Virudhunagar  and Kanyakumari
14.Rice (SRI)- Rabi (medium & long duration varieties)	Red sandy loam (Vannapatti series)		FN = 3.49 T- 0.36 SN – 0.74 ON FP2O5 = 1.66 T- 2.76 SP – 0.69 OP FK2O = 2.19 T-0.66 SK – 0.52 OK	Krishnagiri, Dharmapuri Erode  and Karur
15.Wheat   (Hills)	Sandy clay loamLaterite (Ooty Series)		FN = 7.60T – 0.55 SN – 0.92 ON FP2O5 = 3.59T – 0.26 SP  – 0.54 OP FK2O = 3.88T – 0.45SK  –  0.51 OK	Nilgiris, Salem and foot hills of Tamil Nadu.
16.Wheat   (Plains)	Clay loam Mixed black calcareous (Perianaicken-palayam series)		FN = 8.83 T – 0.71 SN – 0.88 ON FP2O5 = 4.52T –  1.75 SP  – 0.95 OP FK2O = 6.05T –  0.20SK  – 0.83 OK	Coimbatore,Tiruppur, Dindigul, Salem, Tiruchirappalli, Ariyalur, Dharmapuri, Krishnagiri, Villupuram and Vellore.
17.Maize – Kharif (varieties)	Clay loam Mixed black calcareous (Perianaicken- palayam   series)		FN = 4.60 T – 0.55 SN FP2O5 = 2.25T –  1.80 SP FK2O = 5.16T –  0.49 SK	Coimbatore, Tiruppur, Dindigul,Salem, Tiruchirappalli, Ariyalur, Dharmapuri, Krishnagiri,Villupuram and Vellore.
18.Maize – Rabi (varieties)	Clay loam Mixed black calcareous (Perianaicken-palayam series)		FN = 5.29 T – 0.38 SN- 0.78 ON FP2O5 = 2.08 T – 1.29 SP- 0.89 OP FK2O = 5.20 T – 0.45 SK- 0.78 OK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirappalli, Ariyalur,  Dharmapuri,  Krishnagiri, Villupuram and Vellore.
19.Hybrid Maize	Red sandy loam (Palaviduthi series)		FN = 3.96 T – 0.62 SN – 0.69 ON FP2O5 = 1.56 T – 1.93 SP – 0.60 OP FK2O = 1.66 T – 0.27 SK – 0.49 OK	Dindigul, Coimbatore, Tiruchirappalli, Madurai, Karur, Theni, Ariyalur and Thiruvallur.
20.Hybrid Maize	Clay loam Mixed black calcareous (Perianaicken-palayam series)		FN = 4.01 T – 0.76 SN – 0.83 ON FP2O5 = 1.57 T –  2.71 SP – 0.61OP FK2O = 2.09 T – 0.26 SK – 0.65 OK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirappalli, Ariyalur, Dharmapuri, Krishnagiri, Villupuram and Vellore.
21.Hybrid Maize	Sandy clay  to clay Black calcareous (Pilamedu series)		FN = 3.78 T – 0.78 SN – 0.89 ON FP2O5 = 1.47 T – 2.02 SP – 0.91 OP FK2O = 1.79 T – 0.14 SK – 0.62 OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Perambalur, Ariyalur, Dharmapuri and Virudhunagar.
22.Rainfed maize	Red sandy loam (Irugur series)		FN = 3.23 T- 0.42 SN – 0.52 ON FP2O5 = 1.51 T – 1.98 SP – 0.94 OP FK2O = 1.73 T – 0.21 SK – 0.48 OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore and Thiruvallur.
23.Sorghum     (Hybrids)	Red sandy loam (Irugur series)		FN = 4.86T-0.53 SN-0.98 ON FP2O5 = 1.63T-0.87 SP-0.90  OP FK2O = 4.56T-0.59SK-0.76  OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri,Krishnagiri, Vellore and Thiruvallur.
24.Sorghum       (varieties)	Clay loam Mixed black calcareous (Perianaicken-palayam series)		FN = 6.06T – 0.81 SN – 0.53 ON FP2O5 = 2.06T – 3.14 SP – 0.72 OP FK2O = 5.03T – 0.47 SK- 0.66 OK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirappalli, Ariyalur, Dharmapuri, Krishnagiri, Villupuram and Vellore.
25.Ragi	Clay loam Mixed black calcareous (Perianaicken-palayam series)		FN = 4.35T-0.37 SN-0.98 ON FP2O5 = 1.18T-1.03 SP-0.80 OP FK2O = 2.68T-0.14 SK-0.40 OK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirapalli, Ariyalur, Dharmapuri,  Krishnagiri, Villupuram and Vellore.
26.Ragi	Red Sandy  clayloam (Somayanur series)		FN = 4.94 T-0.55 SN FP2O5 = 1.36T-0.96 SP FK2O = 4.20T-0.46 SK	Coimbatore, Tiruppur, Salem, Namakkal, Madurai, Dindigul, Theni  and Villupuram.
27.Pearl millet	Clay loam Mixed black calcareous (Perianaickenpa- layam series)		FN = 6.04T-0.49 SN-0.80 ON FP2O5 = 2.78T-1.65SP-0.97   OP FK2O = 3.29T-0.17 SK-0.58 OK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirapalli, Ariyalur, Dharmapuri, Krishnagiri, Villupuram and Vellore.
28.Little millet	Red sandy loam (Irugur series)		FN = 8.83T – 0.41 SN – 0.55 ON FP2O5 = 3.75T – 1.10 SP  – 0.62 OP FK2O = == 4.57T – 0.15 SK – 0.48 OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore and Thiruvallur.
29.Blackgram	Clay loam Mixed black calcareous (Perianacken- palayam series)		FN = 10.84T-0.39 SN FP2O5 = 7.23T-1.00   SP FK2O = 5.20T-0.04   SK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirappalli , Ariyalur, Dharmapuri, Krishnagiri, Villupuram  and Vellore.
30.Greengram	Red sandy loam      (Irugur series)		FN = 25.07 T – 0.71 SN FP2O5 = 15.44 T – 5.48 SP FK2O = 11.00 T – 0.19 SK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore  and Thiruvallur.
31.Groundnut	Red sandy loam (Irugur series)		FN = 6.54T-0.56 SN-0.69 ON FP2O5 = 3.80T-3.32 SP-0.77  OP FK2O = 8.35T-0.65SK-0.87   OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore and Thiruvallur.
32.Groundnut	Red sandy clay loam (Somayanur series)		FN = 6.54 T – 0.51 SN -1.10 ON FP2O5 = 4.19 T – 2.95 SP – 0.77 OP FK2O = 5.47 T – 0.33SK – 0.87 OK	Coimbatore, Tiruppur, Salem, Namakkal, Madurai, Dindigul, Theni and Villupuram.
33.Groundnut	Low level Laterite		FN = 5.97 T – 0.45 SN FP2O5 = 3.80 T – 3.32 SP FK2O = 7.08 T – 0.58 SK	Cuddalore, Villupuram, Pudukottai, Sivagangai, Tiruvannamalai  and Thanjavur.
34.Rainfed groundnut	Red Sandy clay loam (Somayanur series)		FN = 7.50 T – 0.33 SN – 0.45ON FP2O5 = 3.50 T – 1.67 SP – 0.55 OP FK2O = 6.78 T – 0.31 SK – 0.43 OK	Coimbatore, Tiruppur, Salem, Namakkal, Madurai, Dindigul, Theni and Villupura
35.Sunflower	Clay loam Mixed black calcareous (Perianaicken-palayam series)		FN = 9.60T-0.49 SN-0.68 ON FP2O5 = 4.20T-1.87 SP-0.80 OP FK2O = 9.24T-0.45SK-0.64 OK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirappalli, Ariyalur, Dharmapuri, Krishnagiri, Villupuram and Vellore.
36.Gingelly	Clay loam Black alluvium      (Adanur series)		FN = 13.07 T-0.46 SN FP2O5 = 6.30   T-1.79 SP FK2O = 12.8   T-0.47 SK	Erode, Thanjavur, Tiruvarur, Nagapattinam, Tiruchirappalli, Karur  and Cuddalore.
37.Sugarcane	Clay loam Mixed black calcareous (Perianaickenpal-ayam series)		FN = 4.17 T – 1.09 SN – 1.11ON FP2O5 = 1.01 T – 2.56 SP – 1.01 OP FK2O = 3.44 T – 0.84 SK – 1.03  OK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirappalli, Ariyalur, Dharmapuri, Krishnagiri, Villupuram and Vellore.
38.Sugarcane	Clay loam Red coastal alluvium (Gadillum series)		FN = 4.06T – 0.74 SN – 0.87ON FP2O5 = 0.71T – 1.09 SP  – 0.72OP FK2O = 2.67T-  0.57 SK – 1.33 OK	Cuddalore and Villupuram.
39.Sugarcane	Red sandy loam (Irugur series)		FN = 3.42 T – 0.56 SN -0.93 ON FP2O5 = 1.15 T – 1.94 SP – 0.98 OP FK2O = 3.16 T – 0.73 SK- 0.99 OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore and Thiruvallur.
40.Cotton          (varieties)	Clay loam Mixed black calcareous Perianaicken- palayam series)		FN = 8.81 T – 0.62 SN FP2O5 = 2.53 T – 1.36 SP FK2O = 4.92 T – 0.25 SK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirappalli, Ariyalur, Dharmapuri, Krishnagiri, Villupuram, Ramanathapuram and Vellore.
41.Cotton (varieties)	Red sandy loam (Irugur series)		FN = 7.66T – 0.43 SN – 0.71 ON FP2O5 = 3.22T – 3.27 SP – 0.87 OP FK2O = 5.97T – 0.50 SK – 0.66  OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore and Thiruvallur.
42.Cotton under  Drip fertigation (Hybrid )	Clay loam Mixed black calcareous (Perianaicken- palayam series)		FN = 8.51T – 0.40 SN – 0.73 ON FP2O5 = 4.41T- 2.25 SP – 0.75  OP FK2O = 6.59T- 0.18 SK – 0.66 OK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirappalli, Ariyalur, Dharmapuri, Krishnagiri, Villupuram and Vellore.
43.Hybrid cotton (Rainfed)	Sandy clay  to clay Black calcareous (Pilamedu series)		FN = 5.35T – 0.24 SN – 0.53ON FP2O5 = 3.67T – 1.99 SP – 0.84 OP FK2O = 3.83T – 0.13 SK – 0.55 OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Perambalur, Ariyalur, Dharmapuri and Virudhunagar.
44.Aggregatum (small) Onion	Red sandy loam (Irugur series)		FN = 0.99T-0.37 SN-0.58 ON FP2O5 = 0.58T-1.43 SP-0.69  OP FK2O = 0.67T-0.25SK-0.44  OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri,Vellore and Thiruvallur.
45.Big onion	Red sandy loam (Irugur series)		FN = 0.80T- 0.60 SN – 0.84 ON FP2O5 = 0.58T – 2.10 SP – 0.87 OP FK2O = 0.61T – 0.33 SK – 0.70 OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore and Thiruvallur.
46.Bhendi	Clay loam Mixed black calcareous (Perianaicken- palayam series)		FN = 1.15T-0.46 SN – 0.81ON FP2O5 = 0.52T-1.31 SP – 0.87 OP FK2O = 1.77T-0.64SK – 0.91 OK	Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirappalli, Ariyalur, Dharmapuri, Krishnagiri, Villupuram and Vellore.
47.Cabbage	Red sandy loam (Irugur series)		FN = 0.55T-0.89 SN – 0.76 ON FP2O5 = 0.29T-2.75 SP – 0.86 OP FK2O = 0.36T-0.31SK – 0.56 OK	Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore and Thiruvallur.
48.Tomato	Red sandy loam (Palaviduthi series)		FN = 0.45T- 0.63 SN – 0.72 ON FP2O5 = 0.42T – 4.18 SP- 0.73 OP FK2O = 0.40T – 0.48 SK- 0.66 OK	Dindigul, Coimbatore, Tiruchirappalli,Madurai, Karur, Theni, Ariyalur and Thiruvallur.
49.Brinjal	Red sandy loam (Palaviduthi series)		FN = 0.69T- 0.72 SN – 0.64 ON FP2O5 = 0.41T – 3.57 SP-  0.72 OP FK2O = 0.65T – 0.34 SK – 0.52 OK	Dindigul, Coimbatore, Tiruchirappalli,Madurai, Karur,Theni, Ariyalur and Thiruvallur.
50.Beetroot	Red sandy clay loam (Palathurai series)		FN = 0.64T-0.65 SN -0.96 ON* FP2O5 = 0.52T-1.58 SP -0.92 OP FK2O = 0.61T-0.27SK -0.92  OK	Coimbatore, Tiruppur, Erode, Karur, Namakkal, Tiruchirappalli,  Perambalur, Dindigul, Theni, Ariyalur, Krishnagiri,  Virudhunagar and Vellore
51.Radish	Red sandy clay loam (Palathurai series)		FN = 0.69T – 0.74SN-1.03 ON FP2O5 = 0.28T – 1.35 SP-1.15 OP FK2O = 0.43T – 0.21SK-0.64 OK	Coimbatore, Tiruppur, Erode, Karur, Namakkal, Tiruchirappalli, Perambalur, Dindigul, Theni,Ariyalur, Krishnagiri, Virudhunagar and Vellore
52.Potato	Laterite  (Ooty Series)		FN = 0.70T- 0.24SN – 0.41 ON FP2O5 = 1.44T-0.55 SP – 0.95 OP FK2O = 0.72T-0.25SK – 0.39 OK	Nilgiris and Dindigul
53.Cauliflower	Red sandy loam (Irugur series)	FN = 0.93T-0.79SN – 0.63 ON FP2O5 = 0.44T-1.74 SP – 0.85 OP FK2O = 0.44T-0.18SK – 0.46 OK		Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri, Krishnagiri, Vellore and Thiruvallur
54.Carrot	Laterite (Ooty series)	FN = 0.48T-0.17 SN-0.33ON FP2O5 = 1.11T-1.17 SP-0.31 OP FK2O = 0.83T-0.40SK-0.43OK		Nilgiris,Salem and Dindigul.
55.Tapioca	Red Sandy loam (Thulukkanur series)	FN = 0.56T-0.61 SN-0.81 ON FP2O5 = 0.35T-1.80 SP-0.53 OP FK2O = 0.94T-0.67SK-0.70 OK		Erode, Karur, Salem, Namakkal, Tiruchirappalli, Ariyalur, Madurai,Theni and Dharmapuri
56.Chilli	Red sandy loam (Irugur series)	FN = 8.29 T – 0.32 SN FP2O5 = 7.13 T – 5.24 SP FK2O = 5.86 T – 0.15 SK		Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri and Krishnagiri.
57.Turmeric	Red sandy loam (Irugur series)	FN = 1.11T – 0.83 SN-0.98 ON FP2O5 = 0.57T-5.21SP-1.02OP FK2O = 0.83T-0.50 SK-0.61OK		Coimbatore, Tiruppur, Erode, Salem, Namakkal, Tiruchirappalli, Madurai, Dindigul, Theni, Karur, Ariyalur, Dharmapuri and Krishnagiri.
58. Ashwagandha	Clay loam Mixed black calcareous (Perianaickenpal-ayam series)	FN = 24.77T-0.61SN-0.74 ON FP2O5 = 18.33T-2.68 SP-0.84 OP FK2O = 18.12T-0.21SK-0.59 OK		Coimbatore, Tiruppur, Dindigul, Salem, Tiruchirappalli, Ariyalur, Dharmapuri, Krishnagiri, Villupuram and Vellore.
59.Glory Lily	Red sandy loam (Palaviduthi series)	FN = 41.45 T – 0.53 SN – 0.71 ON FP2O5 = 23.08 T – 1.92 SP – 0.88 OP FK2O = 30.45 T – 0.21 SK-0.64 OK		Dindigul, Coimbatore, Tiruchirappalli, Madurai, Karur, Theni, Ariyalur and Thiruvallur.
60.Chrysanthemum	Red sandy clay loam (Somayanur series)	FN = 2.01 T – 1.14 SN – 0.67 ON FP2O5 = 1.08 T – 2.56 SP – 0.69 OP FK2O = 1.57 T – 0.74 SK – 0.62 OK		Coimbatore, Tiruppur, Salem, Namakkal, Madurai, Dindigul, Theni and Villupuram.

Note:(i)FN, FP₂O₅ and FK₂O respectively are fertiliser N, P₂O₅ and K₂O in kg ha^-1;T is the yield target in q ha^-1 (except for Sugarcane T is in t ha^-1)   and SN, SP  and SK respectively are alkaline KMnO₄-N, Olsen-P and NH₄OAc-K in kg ha^-1; ON, OP and OK are the quantities of N, P and K in kg ha^-1 supplied through FYM

(ii) Based on the contribution of nutrients from organic manures and biofertilizers,the quanttity of fertilizerN, P₂O₅ and  K₂O to be deducted from the total quantity of  fertilizer N, P₂O₅ and  K₂O.

Long term STCR-IPNS demonstration on rice-rice sequence in wetland farm, TNAU is in progress since 1998 and it is a standing evidence for demonstrating the benefits of adoption of STCR-IPNS technology interms of sustained yield and soil fertility.

To popularize the STCR-IPNS technology among the tribal farmers totally 285 Front Line Demonstrations on various crops viz., rice, maize, finger Millet, black gram, green gram, groundnut, gingelly, sunflower, sugarcane, cotton, onion, carrot,  radish, tomato, chilli, bhendi, brinjal, tapioca and turmeric were conducted at  farmers holdings of Coimbatore, Salem, Tiruppur and Dindigul. Also eleven  numbers of field day cum trainings, one no. of exposure visit and twelve numbers of exhibitions were organized for the benefit of tribal farmers. Irrespective of the crops, STCR-IPNS based prescription excelled blanket fertilizer recommendation and farmers practice in terms of yield, nutrient use efficiency and benefit cost ratio.

 

• DSSIFER 2010 (Decision Support System for Integrated Fertiliser Recommendation)

DSSIFER A user friendly computer software has been developed for providing STCR-IPNS based fertilizer recommendations for various crops and soils of Tamil Nadu.  It also provides quality appraisal of  irrigation water and reclamation  measures for problem soil management. It is being used in Soil Testing and Technology Advisory Centre (SOTAC) of TNAU, STLs of KVKs, block level Mini STLs, NGOs, private entrepreneurs, progressive farmers etc.,

• GPS and GIS based Soil Fertility Maps

Under the DAC, New Delhi sponsored project through ISSS, Bhopal GPS and GIS based taluk wise soil fertility maps  for  macro and micro nutrients  indicating low, medium and high nutrient status were prepared for eleven  selected districts of Tamil Nadu viz., Thanjavur, Nagapattinam, Thiruvarur, Cuddalore, Villupuram, Salem, Tiruchirappalli, Erode, Coimbatore., Dindigul and Tiruppur.

 

• Twenty different medicinal plants were screened and grouped for different EC levels of irrigation water. 19 sp. viz., Adathoda vasica, Aloe vera, Andrographis paniculata, Cassia angustifolia, Catharanthus roseus, Coleus forskholii, Datura metel, Eclipta alba, Gloriosa superba, Gymnema sylvestre, Lucas aspera, Ocimum sanctum, Phyllanthus amarus, Plantago ovata, Rauvolfia serpentina, Solanum viarum, Solanum nigrum, Solanum trilobatum and Withania somnifera (Except Stevia sp) can be cultivated upto 4 EC; 9 sp. viz.,Adathoda vasica, Aloe vera, Cassia angustifolia, Datura metel, Gloriosa superba, Ocimum sanctum, Solanum viarum, Solanum trilobatum and Solanum nigrum can be cultivated upto 6 EC; 4 sp.viz., Adathoda vasica, Aloe vera, Gloriosa superba and Solanum trilobatum can be cultivated upto 8 EC; 3 sp.viz.,Adathoda vasica, Aloe vera and Gloriosa superba can be cultivated upto 10 EC.

 

2. Radioisotope (Tracer) Research Findings

 

• Sulphur use efficiency of the applied fertilizer as elemental sulphur in groundnut ranged from 5.45 – 15.89 %.

• P acquisition characteristics of cotton and maize with radiotracer P (³²P) showed that maize was able to utilize the sparingly soluble forms of P namely Ca-P and Fe- P in soil.
• Organics were found to be equally effective as SSP in phosphorus contribution to the main crop of maize and performed better in the residual crop, sunflower
•  The genotypes Co5, APK 1 and VBN 2 were identified as efficient genotypes in Pigeon pea for utilizing the Fe-bound (fixed)  phosphorus
•  Surface application of phosphate to paddy soils was found to be  more efficient over deep placement
•  Calcium and sulphur utilisation efficiencies in groundnut were higher from gypsum than from calcium chloride or potassium sulphate
•  The utilization efficiency of applied  zinc   seldom exceeded 1% in rice
•  The utilization of applied iron  in Crossandra was  5.1 to 6.9%
•  Root distribution pattern of cereals and tree crops

 

 

 

 

3. Micro and Secondary nutrients and Pollutant elements in soils and plants Findings

 

• Delineated the soils of Tamil Nadu for secondary and micronutrients status and developed thematic soil fertility maps

 

Collected and analyzed the soils samples (46,180) from all 31 districts in Tamil Nadu at village level for secondary and micronutrients status and found predominant Zn deficiency (45.2%) followed by B (19.9%) and Cu (16.7%). The deficiency of S, Fe and Mn was 10 -15 per cent in the soils.

 

Agro climatic Zone	Sample size	Zn	Fe	Mn	Cu	B	S
North Eastern Zone	13,741	46.0	9.25	11.7	17.0	17.0	6.39
North western zone	5,392	48.2	6.81	3.96	4.15	20.1	13.0
Western zone	3,389	38.8	15.9	11.8	21.4	52.7	5.45
Cauvery Delta zone	8,991	33.8	7.64	2.84	13.9	14.1	7.68
Southern zone	13,898	56.8	13.4	4.36	24.6	15.7	19.2
High rainfall zone	617	18.3	6.36	0.43	15.9	18.9	7.25
Hilly zone	152	51.1	0.00	0.00	0.37	18.4	5.83
State Overall	46,180	45.2	10.0	5.84	16.7	19.9	11.2

 

• Evaluation of soil test methods for micronutrients assessment
• Evaluation of AB – DTPA with other standard extractants for multi-nutrient extraction in soils revealed the feasibility of using AB-DTPA for extracting K and micronutrients only however it is not a reliable method for determining P and S in acid soils.
• Hot water is the most suitable extractant for the determination of available B in all soils (r = 0.574**), however, 0.1 M salicylic acid in acid soils (r = 0.530**) and 0.05 M mannitol – 0.01 M CaCl₂ (r = 0.368*) in alkaline soils were also found equally effective hence can be a used as an alternative to hot water.
• Fixing critical limit for micronutrients in soils

The critical limit for various soil types were fixed to make fertilizer recommendations which were also redefined for Zn and Cu recently.

Nutrients	Test crops	Soils	Critical limit in soil (mg kg-1)
			Deficient	Medium	High
Zinc*	Rice, Maize, Sorghum,  Groundnut	All  soils	< 0.85	0.85 – 1.60	>1.60
Iron*	Sorghum	Calcareous	< 6.40	6.40 – 8.00	>8.00
		Non calcareous	< 3.70	3.70 – 8.00	>8.0
Manganese*		All  soils	< 2.00	2.00 – 4.00	> 4.00
Copper*	Sorghum, Finger millet, Maize, Onion	All  soils	< 0.63	0.63 – 1.00	> 1.00
Boron**	Groundnut	All  soils	< 0.46	0.46 – 1.00	> 1.00
Sulphur***	Pulses	All  soils	< 10.0	10.0 -15.0	> 15.0
	Extractants used	* 0.005 M DTPA         ** Hot water     *** 0.15% CaCl2

 

• Screening crop varieties for micronutrients efficiency

Crop varieties for micronutrient efficiency were screened to enrich crop produces through bio-fortification and recommended to micronutrient deficient soils. The following crop varieties were found to be efficient, in-efficient and moderately susceptible to micronutrient deficiencies.

 

Crops	Elements	Susceptible	Moderately susceptible	Tolerant
Rice	Zn	ADT 27, IR 20, ADT 36, ADT 37,  IR 64 ,  IR 62 , ASD 18, ASD 19, ADT 39,  CO 43, CO 40, Improved White Ponni, ADT 44	GEB 24, ASD 5, Karuna, IR 24, TKM 6, CO 25, Vaigai, Bhavani, ADT 34, ADT 35, ASD 15	Kanchi ,CO 36, CO42,  IET 3280, IR 50, ASD 16, Kannagi,  CO 44, CO 47, ADT 43,  ADT (RH) 1, CO 47, CO 51, ADT 37, ADT 47
	Fe	Bhavani, CO 34	–	–
	Fe toxicity	ADT 42, IR 50, MGR 1 and ADT 36	–	TPS 1, ASD 16, ASD 18, IR 64, JJ 92, TKM 9, CO 37, CO 41
	Mn	CO 34, CO 36	–	CO 33, CO 37, CO 38, CO 39, CO 40, CO 41, CO 42, Bhavani
Bajra	Mn	KM 2, VCH 4, KM 1 ,	–	K 2, CO 6
Sorghum	Zn	CO 26, COH 4	–	CO 25, CSV13, SPV 881
	Fe	USV 5, CSH 1, CO21,CO 24, SPU 881, CO 4 , CO 23, TNSH 239, CS 3541	IS 3541, CSH5, CO22, USV 3 TNS 294, CO 25	K tall, SPV 86, CSH6, TNSH 136, TNS 30, TNS 265, CO 26
Maize	Zn			CP18, Nidhi 33,NK 30, NK21,907Z
	Fe	CO 9	CO 7, CO 10	CO 6, CO8,
Greengram	Zn	TM 96-2,LGG 407	VBN 2, VRM GG 1, Pusa bold, KM1, KM 2, ADT 3, Rajendran, LGG 460, LGG 450, LGG 486, LGG 410, CO5, K 851, CO 4, Paiyur 1	CO7, CO 6, VBN 1
	Fe	T.K.Local	TMV 1, CTU 17-4	ADT3, CO6,TMV 1
Blackgram	Fe	T.K.Local	TMV 1, CTU 17-4	ADT3, CO6,TMV 1
Groundnut	Zn	TMV 7, TMV 2, CO1	–	POL1, POL2, TMV 9, TMV 11, TMV12,
	Fe	VRI 2, CO1, JL 24, ALR 320, CO 4, TMV 2, ALR 2	VRI 6, ALR1	TNAU- 28, CO 7,  CO 2, ALR 3, VRI 8 TMV 13
	S	Local, VRI4, CO3, VRI 2, VRI7, TMV2, ALR3, and BSR 1	CO1, VRI 8, TMV 10	VRI 6, CO 7, TMV 7, TMV 13, VRI 5, VRI 3, CO2, CO6
Soybean	Zn	GPM – IC – 15750	–	GPM – EC – 2581
	Mn	UGM 20, UGM 21, Punjab 1	–	M2, M3, Davis
	Mo	UGM 20, UGM 21	–	M2, Davis

 

• Bio-fortification of micronutrients in crops

Bio-fortification studies were carried out to enrich the grains of major crops such as rice and pulses and the following varieties were suitable for bio-fortification of Zn.

 

Zn efficient	Rice- short duration	CO 51, CO 47, ADT 36, ADT 37
	Rice- Medium duration	CO 50, TRY 1, DRRH 5,CORH 4, ADT 46
	Greengram	CO 6,CO7, Paiyur 1,VBN 2
Fe efficient	Greengram	CO 6
	Blackgram	CO 6, ADT 3, TMV 1

 

The following technologies were identified for bio-fortification of micronutrients

1. Foliar spraying of 0.25 % of each CuSO₄, ZnSO₄, FeSO_4, MnSO₄ + 0.10 % Boric acid + 0.01 % Sodium molybdate at active tillering, panicle initiation and flowering stages
2. Basal soil application of 50 kg ZnSO₄ ha^-1 + 0.5 % ZnSO₄ foliar spray thrice at flowering, milk and dough stages in rice, twice in greengram (30 and 45 DAS) and maize (40 & 55 DAS).

• Optimizing the rate of soil and foliar application of secondary and micronutrients for crops and cropping systems

The following recommendations were evolved for improving the soil health and yield of various agricultural and horticultural crops. Soil application of these recommendations can be followed for the soils having the particular element deficiencies. Foliar spraying of the specific recommendations for the micronutrients can be adopted if the plants show deficiency symptoms at an interval of 7-10 days for short duration crops and 15 days for long duration crops.

1. Crops

Nutrients	Crops	Technologies (kg ha-1)
		Soil application	Foliar spray
Zn (ZnSO4)	Rice, Sorghum, Maize, Cumbu, Ragi, Pulses, Groundnut, Sunflower, Sesame  Beetroot, Radish, Carrot, Garlic, Onion	25.0	0.50 %
	Turmeric, Cotton, Tobacco, Grapes	50.0
	Sugarcane, Maize, Wheat, Cabbage, Cauliflower	37.5
Fe (FeSO4)	Semi dry and rainfed  Rice, Sorghum, Maize, Groundnut	50	1% + 0.1% Citric acid
	Sugarcane, Tobacco, Turmeric	100
B (Borax)	Maize, Groundnut, Cowpea, Horsegram, Lablab, Pulses, Beetroot, Radish, Carrot, Garlic, Brinjal, Coriander, Beans, Knol-Khol, Tapioca, Banana, Vegetable Cowpea	10	0.20 %
Cu (CuSO4)	Rice, Tomato, Cabbage, Onion	5-10	0.20 %
Mn  (MnSO4)	Onion, Sesame	10	0.50 %
Mo (Sodium/ Amm. Molybdate)	Pulses, Fodder Cowpea, Cauliflower, Cabbage	0.50/ 0.25	0.05%
Sulphur (SSP, Gypsum)	Rice, Wheat, Groundnut, Oilseeds, Pulses, Tapioca, Onion	20 – 40	–
Magnesium (MgSO4)	Potato, Cotton	50	2.0%

 

 

 

1. Cropping systems

Nutrients	Cropping systems	Technologies developed (Basal soil application ha-1)
Zn	Rice- Rice	25 kg ZnSO4 for every crop  or 50 kg ZnSO4 once in three crops or 100 kg ZnSO4 once in six crops
		12.5 kg ZnSO4 for every rice or 37.5 kg ZnSO4 once in a year
	Rice- Pulse	37.5 kg ZnSO4 to first crop rice
	Sorghum- Cotton	25 kg ZnSO4 to Sorghum crop and 12.5 kg ZnSO4 to cotton
	Sunflower-Maize	37.5 kg ZnSO4 to 1st sunflower and 12.5 kg ZnSO4 for subsequent crops in the sequence
	Maize – black gram	50 kg ZnSO4 + 10 kg Borax to main crop  alone or individual application of 37.5 kg ZnSO4 + 10 kg borax for maize and 25.0 kg ZnSO4 +10 kg Borax for blackgram
S	Rice- Cotton	30 kg S as gypsum or SSP or Ammonium sulphate to the first crop
B	Sunflower-Greengram	10 kg borax to sunflower
	Groundnut – Sorghum	20 kg borax to first crop and later 5 kg Borax to 2nd, 4th and 6th crop in the sequence
	Maize- sunflower	5 kg Borax to every crop or 10 kg Borax to first crop in the sequence

 

• Bio-transfer of micronutrients and heavy metals in soil-plant-animal-continuum

 

1. Studies on bio-transfer of Zn in soil-plant-animal continuum conducted by feeding Zn enriched fodder to milch animals, heifers and cows revealed considerable increase in Hemoglobin (1.64 to 6.56%) and  Zn content in milk and serum (10-20%).
2.  Feeding heavy metal contaminated Cumbu Napier grass to Jersey cross animals at 30 kg per day for 28 days showed toxic level of Cd and Ni in milk and seven fold increased accumulation of Ni and Cr in blood. Continuous feeding of metal contaminated fodder increased the metal accumulation as : Cow dung > Blood > Milk samples.

 

 

• Pollution studies

Investigations carried out to identify the metal specific hyper accumulators lead to the following recommendations to remediate the contaminated sites in various districts of Tamil Nadu

Extent of metal pollution

City Classification	Districts	Polluted metal	Recommended hyper accumulators
Highly populated	Coimbatore, Madurai, Trichy	Zn, Pb,Cd, Cr, Ni, Cu	Eucalyptus, Casuarina, Acacia
Medium populated	Salem, Erode	Zn, Cu, Cd, Cr	Phyllanthus
		Ni	Castor
Low populated	Karur, Pudukottai	All Metals	No non-food crop is available

 

1. Hyper accumulators for phyto-remediation of contaminated soils

Elements	Tree sp.	Grasses	Vegetables	Greens	Flower crops
Zn	Eucalyptus sp. Moringa	Guinea grass	–	Ponnanganni	Marigold
Cu	Acasia		–	Ponnanganni	Globe Amaranth, Aster
Pb	Eucalyptus sp. Moringa	Cyprus	Cluster bean	Amaranthus	Marigold, Zinnia, Blossam, Aster, Globe Amaranth
Cd	Casurina	Water grass	Lab lab	–	Marigold
Cr	Casurina	Bajra Napier	Lab lab	Sirukeerai	–
Ni	Casurina	Water grass	Lab lab	Sirukeerai	Globe Amaranth, Marigold, Zinnia

 

Threshold toxicity limit for Ni and Cd

Crops	Red soil		Black soil		Red soil		Black soil
	Cd	Cd +FYM	Cd	Cd +FYM	Ni	Ni+FYM	Ni	Ni+FYM
Amaranthus	2.5	20.0	5.00	80.0	5.0	80.0	10.0	40.0
Bhendi	5.0	80.0	10.0	80.0	10.0	40.0	20.0	40.0

 

1. Sewage biosolid compost or sewage coir pith pellets at 2.50 to 5.0 t ha^-1 is recommended to increase the yield of crops.

 

2. Application of 100 mg EDTA kg^-1 along with either 5 t FYM or Green leaf manure ha^-1 was found to be the best in remediating Pb contaminated soils.

 

• Interactive Visual Diagnostic Kit (VDK) for identifying plant nutrient deficiencies and their management was released during 2007. Hands on training and demonstrations on the technology was given to various stakeholders of the State regularly

• 11 crop specific micronutrient mixtures for various crops (rice, sugarcane, cotton, groundnut, sunflower, sesame, castor, pulses, millets, coconut) were developed and released as technology during 2007.

4. ¹⁵ N studies and Long Term Fertilizer Experiment Findings

• N use efficiencies quantified in rice (26 %), millets (25 %), cotton (39%) and oilseeds (16%).
• Atmospheric N fixation in rice (22 kg ha^-1), sorghum (18 kg ha^-1), maize (12 kg ha^-1) and forest trees (1.5 % of DMP)
• Developed slow release fertilizer pellets for rice, banana and sugarcane
• Nutriseed pack techniques for enhancing FUE and yield in rice and maize
• Lessons learnt from Long Term Experiments ten decades revealed that, INM Practices could improve the yield of finger millet and maize under intensive cropping system. Also, application of 100 % NPK + FYM consistently improved the soil health by sustained soil physcio-chemical, biological prosperities and soil organic carbon stocks in soil over 10 decades in continuous fertilizers experiment.

 

• Crop Production by Nutriseed Pack Technique

Crop Production by Nutriseed Pack Technique is a simplest way of raising crop by placing Nutriseed Pack in soil. Each Nutriseed Pack contains seed at top, enriched manure in the middle and encapsulated fertilizer at bottom. By placing a Nutriseed Pack vertically or horizontally in soil, each plant can be established. Nutriseed Pack gives support for each plant in the root zone in terms of optimum nutrient supply, biological activity, etc. and consequently enables the fullest utilization of nutrients by plants. There is no wastage of fertilizer nutrients with Nutriseed Packs.

Nutriseed Pack (NSP)

NSP for Maize crop

Prototype machine for fabrication of fertilizer pellet

Manure pelleting Machine

5. Soil Physics Research Findings

• Chisel technology for sub soil hard pans.
• Compaction Technology for excessive permeable soils.
• Drum Roller compaction technology for fluffy paddy soils.
• Technology for soil surface crusting.

Delineation of soil physical constraints of Tamil Nadu