1

All India Coordinated Research Project On

Long -Term Fertilizer Experiments To Study Changes In Soil Quality, Crop Productivity And Sustainability

Introduction of high yielding varieties, irrigation and high analysis fertilizer accelerated the mining of nutrient other than supplied eternally from soil. To sustain the productivity it was essential to maintain the supply of nutrient. Since large amount of nutrient has to be applied to soil in chemical form which may have impact on soil properties and soil productivity in long term. Therefore, to study the impact of chemical fertilizer on productivity and soil quality, the Indian Council of Agricultural Research decided to launch the “All India Coordinated Research Project on Long-Term Fertilizer Experiments (AICRP-LTFE)” in September 1970 at 11 centres. The work carried out at different centers of LTFE was reviewed by QRT during 1997 and recommended to enlarge the mandate and objectives of the project and changed its title as AICRP on “Long-term fertilizer experiments to study changes in soil quality, crop productivity and sustainability”. The purpose of conducting long term fertilizer experiments at fixed sites in different agroecological zones (AEZ) with important cropping systems was not only to monitor the changes in soil properties and yield responses and soil environment due to continuous application of plant nutrient inputs through fertilizers and organic sources, but also to help in synthesizing the strategies and policies for rational use and management of fertilizers to improve soil quality and to minimize environment degradation. Thus the thrust of AICRP is on productivity, sustainability and environment safety

2

All India Coordinated Research Project On

Long -Term Fertilizer Experiments To Study Changes In Soil Quality, Crop Productivity And Sustainability

MISSION

Soil Fertility Management through Integrated Plant Nutrient Supply for Enhancing and Sustaining Crop Production and Maintaining Soil Quality

MANDATE

� To conduct coordinated long term fertilizer experiments in different soil types under diversified cropping systems

� To collate information on long term soil fertility trials.

OBJECTIVES

1. To study the effect of continuous application of plant nutrients, singly and in combination, in organic and inorganic forms including secondary and micronutrient elements (as per the need) on crop yield, nutrient composition and uptake in multiple cropping systems

2. To work out the amount of nutrient removal by the crops

3. To monitor the changes in soil properties as a result of continuous manuring and cropping with respect to the physical, chemical and microbiological characteristics of the soil in relation to its productivity

4. To investigate the effect of intensive use of biocidal chemicals (weedicides and pesticides) on the build up of residues and soil productivity

5. To make an assessment of the incidence of soil borne diseases and changes in pests and pathogens under the proposed manuring and cropping programme.

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10 TREATMENTS IN EACH EXPERIMENT

T1 50% optimal NPK dose

T2 100% optimal NPK dose

T3 150% optimal NPK dose

T4 100% optimal NPK dose + hand weeding

T5 100% optimal NPK dose + Zinc or lime

T6 100% optimal NP

T7 100% optimal N

T8 100% optimal NPK + FYM

T9 100% optimal NPK (Sulphur free source)

T10 Unmanured (Control)

LIST OF COORDINATING CENTRE/STATIONS:

Details of Centres of AICRP on LTFE

S.

No.

Location (State) Year

of

start

Taxonomic Class Cropping system

1. CRIJAF Barrackpore (W.B.) 1971 Typic Eutrochrept Rice-wheat-jute fibre

2. PAU Ludhiana (Punjab) 1971 Typic Ustochrept Maize-wheat

3. IARI New Delhi (Delhi) 1971 Typic Ustochrept Maize-wheat

4. TNAU Coimbatore (T.N.) 1971 Vertic Ustopept Fingermillet-maize

5. JNKVV Jabalpur (M.P.) 1972 Typic Chromustert Soybean-wheat

6. GKVK Bangalore (Karnataka) 1972 Kandic Paleustalf Fingermillet-maize

7. ANGRAU RRS Jagtial (AP) 2000 Typic Tropaquept Rice-rice

8. OUAT Bhubaneswar (Orissa) 2002 Aeric Haplustalf Rice - rice

9. BAU Ranchi (Jharkhand) 1972 Typic Haplustalf Soybean-wheat

10. CSKHPKV Palampur (H.P) 1972 Typic Hapludalf Maize-wheat

11. GBPUA&T Pantnagar (Uttaranchal) 1971 Typic Hapludoll Rice-wheat

12. JAU Junagadh (Gujarat) 1996 Vertic Ustochrept Groundnut-wheat

13. Dr. PDKV, Akola (Maharashtra) 1996 Typic Haplustert Soybean-wheat

14. KAU Pattambi (Kerala) 1996 Typic Haplustalf Rice-rice

15. IGKV Raipur (Chhatisgarh) 1996 Typic Haplusterts Rice-wheat

16. MPUA&T Udaipur (Rajasthan) 1996 Typic Ustochrept Maize-wheat

17. MPKV Parbhani (Maharashtra) 1996 Typic Chromustert Soybean -safflower

B

Voluntary centre

18. IASRI New Delhi 1972 - -

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SALIENT ACHIEVEMENTS

• Continuous application of N alone in Alfisol resulted drastic reduction in yield under upland situation. The application on N through ammonium sulphate had more adverse effect on crop yield. However, under submerged conditions the

adverse effect of application of N alone was not so harmful as was recorded in upland situation. Except finger millet at Bangalore and rice at Pattambi all crops

responded to lime. Incorporation of FYM either alone or with lime irrespective of crop and soil condition resulted in further increase in crop yields.

• The data generated under LTFE at different centre disproved the notion that

application of fertilizer and cultivation of soil reduced the SOC. The conjunctive use of chemical fertilizer and FYM always maintained relatively larger amount of

SOC compared to chemical nutrients use. This particular treatment even maintained SOC at Pantnagar also. Thus the use of chemical fertilizer should not

be blamed for decline in SOC. Decline in SOC was noticed only on application of chemical nutrients in either imbalanced form i.e. N or NP or in less quantity which did not return enough amount of crop residue to soil.

• The data on dynamics of available N clearly indicated that balanced application of nutrient invariably resulted increase in available status of N in soil irrespective

of cropping system and soil. However, legume cropping system facilitated the built up in available N in soil. Whereas high rainfall and porosity of soil adversely affected the available status of N in soil.

• Soil analysis indicated that the amount of P applied is always larger than the

uptake of P by the crop. The fertilizer P applied in excess to crop uptake resulted in built up in soil available P. The built up in soil P was again dependent on the

amount of P applied and the productivity of the crop. Application of organic manure facilitated build up in available soil P.

• The result of K status in soil recorded at various centres indicated that absence

of K in fertilizer schedule resulted decline in available K status irrespective soil type and cropping system. Application of NPK+FYM resulted in improvement in

available K status in soil at almost all the places. The decline in magnitude however, was dependent on productivity of crop and the K renewal capacity of the soil. Probably Pattambi and Bhubaneswar are the exceptions where in spite

of absence of K in nutrient supply schedule resulted in increase in soil K status. The increase in magnitude of K was of 5-7 kg ha-1 at Pattambi and 20-25 kg ha-1

at Bhubaneswar. • Micronutrient analyses of soil revealed hidden hunger of Zn in Mollisol of

Pantnagar and Inceptisol of Ludhiana. At these places Zn availability is growth limiting factor. The Other micronutrient cations are available in sufficient

quantity in soil.

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• The results of demonstrations trials conducted at farmers’ field clearly indicated

that the P dose can be reduced to half safely without any reduction in yield. But to enhance the productivity, K is needed in more quantity and part of that could

be supplemented through FYM. To harness greater nutrient utilization efficiency integrated use of chemical fertilizer with FYM is a better option.

• The results of yield experiment clearly indicated that application of P and Zn is essential to harness the potential productivity of crops. But to sustain the

productivity at higher level conjunctive use of chemical fertilizer and FYM is the only option. This supports the strategies developed out of LTFE results.

• The analysis of soil for physical conditions clearly demonstrated that continuous growing of crop with fertilizer resulted decline in bulk density and cone

penetration resistance. However, reverse was found true on hydraulic conductivity and mean weight diameter. The conjunctive use of fertilizer and organic manaure resulted in maximum effect on all the soil physical properties.

• The studies carried out on microbial population at Palampur indicated decline in populations of actinomycetes, bacteria and azotobacter with increase in fertilizer

nutrient application. But increase in the population of these microorganisms was recorded on incorporation of FYM even in presence of fertilizer. Whereas the

reverse was observed on population of fungi. • The yield data of rice-rice at Jagtial, Bhubaneswar and Pattambi clearly

demonstrated that to sustain the productivity of rice-rice system application of all three major nutrients are essential. Of course application of FYM would help

in sustaining the productivity at higher level. • The results of superimposition of treatment indicated that in Alfisols reduction in

P dose did not have any adverse effect on yield of finger millet and maize. Addition of K in 100% NP and superimposition of P and K in 100% N treatment

resulted in very large increase in yield of both finger millet and maize. Farm yard manure (FYM) was found better off amendment i.e. lime.

• The results at Ludhiana clearly showed that curtailment of P dose to half from optimal and super optimal doses did not have any adverse effect on yields of

both maize and wheat. However, to get potential yield of both maize and wheat Zn application is essential. The farmer must keep an eye on P status in soil to

get sustainable yield.

• The results confirmed that Zn and S are yield limiting nutrients at Pantnagar. To

sustain the yield of rice-wheat system at higher level over a period of time, application of Zn and S are essential in addition to NPK. In Alfisol K is the major

growth limiting nutrient.

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100% N is more deleterious in Alfisol than in

Inceptisol

100% N

Alfisol(Palampur)

100% N

100% NPK+FYM

Maize

Wheat

100% NPK+FYM

Inceptisol (Ludhiana)

Maize

100% N application led to no yield of maize and wheat in Alfisol of Palampur compared to relatively less adverse impact in Inceptisols of

Ludhiana

100% N+Lime

100% NPK+FYM

Integrated application of NPK either with lime or FYM sustain soybean productivity at Ranchi

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Impact of K- deficiency on growth and cob quality of hybrid maize at Bangalore

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RESULTS

Productivity of cropping systems in Alfisols

In Alfisols, there are 5 centres of LTFE having different cropping systems viz.: soybean-wheat at Ranchi, maize-wheat at Palampur, finger millet-maize at Bangalore and rice-rice at Bhubaneshwar and Pattambi (Kerala). The yield data (2004-05 & 2005-06) presented in Table 1 revealed that continuous application of nitrogen alone under aerobic (upland) condition resulted drastic reduction in productivity at Ranchi, Palampur and Bangalore. Since last few years at Palampur we could not harvest any grain either of maize or wheat. Though at Bangalore and Ranchi till date the situation of zero yield has not been encountered so far but yield levels are very low and the yields are approaching to zero level. The two years average yield of soybean at Ranchi was 296 kg ha-1 and wheat was 364 kg ha-1. Whereas at Bangalore, the average grain yields of finger millet and maize recorded in N alone treatment were 411 and 159 kg ha-1, respectively. Unlike very poor performance of crops on application of N alone continuously over the years under aerobic condition in Alfisol, the decline in yield of rice-rice under submergence in Alfisol (Pattambi and Bhubneswar) was not noticed. The average yields of kharif (Plate 3.4) and rabi rice on application of N alone at Pattambi were 2165 and 3050 kg ha-1, respectively. Similar trend was also noticed at Bhubaneswar.

Perusal of yield data further revealed that in all the alfisols absence of K from fertilizer schedule resulted reduction of yield in sufficiently large quantity except at Pattambi and Bhubaneswar. The magnitude of reduction in yield varied with site and the crop. Absence of response of rice to K at Patambi is probably due to addition of K through continuous flow of water from forest land situated at upper part of landscape. Whereas at Bhubneswar the river water which is used for irrigation purpose has got catchment of agricultural as well as forest land which might have added K in runoff water. The response of rice to K at Bhubneshwar during kharif indirectly confirms the hypothesis. Because during kharif rains are sufficient to grow rice. The incorporation of lime in Alfisols resulted increase in yield only under aerable situation irrespective of crops except at Bhubneshwar. However, at Bangalore, the finger millet did not show response to lime. The probable the finger millet prefer the acidic condition for its growth.

Sulfur was found to be another growth limiting factor at Bangalore and Palampur. At both the places crop responded to S significantly. Continuous application of N though ammonium sulphate even in presence of other nutrients (P and K) was found to be more harmful compared to application of N through urea. The application N through Ammonium sulphate even in presence of P and K resulted reduction in average yield of soybean from 1496 to 650 kg ha-1 and wheat from 2707 to 1570 kg ha-1 at Ranchi compared to N applied through urea along with P and K. Thus from the yield data of different crops under Alfisols, the following conclusions is drawn:

Continuous application of N nitrogen alone in Alfisol resulted drastic reduction in yield under upland situation. The application on N through ammonium sulphate had more adverse effect on crop yield. However, under submerged conditions the adverse effect of application of N alone was not so harmful as was recorded in upland situation. Except finger millet at Bangalore and rice at Pattambi all crops responded to lime. Incorporation of FYM either alone or with lime irrespective of crop and soil condition resulted in further increase in crop yields.

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Maize –wheat

Yield data of maize-wheat in Inceptisols of Ludhiana presented in Table 1 revealed response to applied P in both the crops. Application of P led to increase in maize and wheat yields to the extent 6 and 10 q ha-1, respectively. Till date crop did not show any response of K and S. like other places and cropping systems, incorporation of FYM over and above NPK sustained the productivity at highest level compared to all other treatments. The yields data of maize and wheat at Udaipur indicated the response to applied P in both the crops. Both maize and wheat also showed response to applied K but the increase in yield my not be statistically significant. It is interesting to note even after application of 25 t FYM, the yield of either maize or wheat are sustained. Significantly larger yields in 150% NPK treatment suggest to enhanced the recommended level of NPK.

Rice-wheat

Yield data of Rice-wheat at Barrackpore revealed that so far none of the crop responded to P. However, at Pantnagar, response to P application was seen only in wheat. So far rice did not response to applied P. Even after 35 years, the response of K was not recorded in the crops neither at Barrackpore nor at Pantnagar. At Pantnagar response of rice to applied Zn was seen but the subsequent wheat did not show response to Zn. At Pantnagar improvement in yield of both rice and was recorded on application of Sulfur. In Inceptisol at Raipur both rice and wheat started showing response to applied P. So far response of K was not observed neither in rice and nor in wheat. At Raipur application of BGA in rice did not increase the yield of rice and wheat also. However, practicing of green manuring resulted in increase in grain yield of rice as well subsequent wheat significantly. The yields of rice revealed that incorporation of 10 t FYM over and above of NPK resulted in significant increase in yield and an appreciable residual effect of FYM was also recorded subsequent wheat yield.

Soybean wheat Yield data of soybean-wheat recorded at Jabalpur clearly indicated very high response of soybean and wheat to applied P. Though Vertisols are inherently rich in K but crop started showing response of K. Relatively larger response was observed in wheat compared to soybean. Both the crops also started showing response to applied S. Incorporation of FYM over and above 100% NPK resulted highest yield of both the crops. Thus results indicated that sustainability soybean-wheat in Vertisol is on stake of external supply of P, K, and S. It is interesting to note that there is no decline in wheat yield in control plot without application of any nutrients since last 35 years. Rather slight improvement in yield of wheat was recorded in last five years block. Improvement in wheat yield in last one decade is probably due to addition of biologically fixed by N soybean.

Rice-Rice

The grain yield of rice-rice in Inceptisol at Jagtial indicated that in general kharif rice yields are larger than the yields of rabi season. Phosphorus is recorded to be growth limiting nutrients and K is likely to be next nutrient which is required to be supplemented to sustain the productivity.

So far there is no response to S in both the seasons. Even after continuous application of FYM @ 10 t ha-1 in both during kharif and rabi could not sustained the yield either any of the rice crops. Probably amount of FYM applied is low. In contrary to Jagtial the yield levels of rice at Pattambi are larger in rabi season compared to kharif. The yield data of both the rice crops

10

revealed that there is no response of rice to even N, P and K. The effect of lime was also not seen on yield of rice. From the data it is clear that to sustain the yield at higher level application of FYM is essential. Here in presence of FYM the yield of rice-rice system could be sustained even at reduced doses of NPK. However, reduced doses of NPK under green manuring may not sustained the productivity. The reason for greater productivity during rabi at Pattambi could be due to larger sunshine hours whereas low productivity during rabi season at Jagtial is assigned to shortage of water. In Alfisol of Bhubaneswar, application of lime resulted improvement in yield of rice in both the season’s. Like in other cropping systems incorporation of FYM over and above 100% NPK sustained the yields of rice at a higher level. But there was no response of rice to any of the nutrients K, P, S, Zn and B. Probably application of river water as source of irrigation could be reason for no response of K and P in spite of being Alfisol. The river has got catchment area of agricultural field and forest land situated at higher elevation of topography. There is need to analyse the irrigation water which might be supplying K and P to soil.

Groundnut-wheat

Groundnut-wheat cropping system is only at Junagadh under LTFE. The yield data of Groundnut revealed response of K application whereas response of K was not recorded in wheat. However, reverse was recorded as far as response of wheat to P is concerned. The response of S was neither recorded in groundnut nor in wheat. It is interesting to note that exclusive application of FYM 25 t ha-1 yr-1 resulted in sustainability of system at par with 100% NPK.

Finger millet-Maize

Finger millet and maize as test cropping system is being used at Coimbatore (Inceptisol) and Bangalore (Alfisol). The yield data of finger millet recorded at Coimbatore indicated response of P in both finger millet and maize. However, finger millet did not show any response to applied K but good response to K was seen in maize. This indicates that it is not necessary that all the crop may show response to a particular nutrient even at same site. Response to a particular nutrient depends on root structure and the nutrient requirement of the crop. The larger yield in 150% NPK treatment compared to 100% NPK suggests that the nutrient doses being applied are not sufficient. Incorporation of 10 t FYM over and above NPK and yielded to all the treatment.

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Table 1. Average grain yield (kg ha-1) of crops during 2004-05 and 2005-06 at AICRP LTFE centres

Location Crop Control N NP 50%

NPK

100%

NPK

150%

NPK

NPK+Zn NPK+

FYM

NPK-

S/+S

NPK+

HW

NPK +

Lime

FYM /

BGA

Barrackpore Rice 983 1595 1525 1325 1688 1775 1169 1871 2025+S 1513 - -

Wheat 723 1533 1665 1340 1533 1863 1722 2097 1667+S 1579 - -

Pantnagar Rice 1935 4780 4990 4195 4655 4655 5310 5540 5015 –S 5270 2080BF -

Wheat 1315 3115 3465 3120 3600 3485 3950 4480 3650-S 3870 1530 BF -

Ludhiana Maize 2079 3202 3874 3219 3966 4599 4220 4840 4153-S 4160 - -

Wheat 1676 2962 3987 2842 3859 4499 4280 4765 4355-S 4195 - -

Palampur Maize 660 0 3005 3625 4605 4495 4525 6130 1995-S 4945 5395 -

Wheat 570 0 1790 1810 2405 2440 2320 3540 1555-S 2715 3395 -

Ranchi Soybean 617 296 861 1232 1496 1460 - 1832 650+S 1503 1766 -

Wheat 684 364 2360 1969 2707 2765 - 3235 1570+S 2756 3088 -

Bangalore F. millet 466 411 472 2039 4072 4769 - 4484 4186-S 3947 3907 -

H. Maize 237 154 492 1457 2628 2981 - 3123 2143-S 2681 2879 -

Pattambi Kharif Rice 1485 2165 2031 2085 2211 2357 - 2487 - - 1787 -

Rabi Rice 2069 3050 3093 2927 3153 3369 - 3913 - - 2730 -

Bhubaneswar Kharif Rice 1230 1980 2090 2250 2430 2210 1940 2470 - - 2410 -

Rabi Rice 1510 2840 2980 2730 2960 2500 3040 3120 - - 2870 -

Junagadh Groundnut 660 831 778 961 1053 1160 1041 1221F 984+S 993STCR 1019R 928F25

Wheat 1937 1706 2645 2369 2684 2801 2564 3562 F 2727+S 2863 STCR 2622R 3354F25

Udaipur Maize 1550 2135 2630 - 2960 3190 3105 3480 3025+S - 3350A 2230F20

Wheat 1780 2785 3355 - 3770 4250 3975 4435 3920+S - 3965A 2620F20

Raipur Rice 2873 4803 6245 5052 6392 6950 6356 6896 - - 5700GM 5192BGA

Wheat 677 1012 1951 1232 1842 2206 1913 2042 - - 1228GM 1155BGA

Jagtial Kharif Rice 3441 4289 5570 4760 5778 6091 5850 6116 5666-S 5878 - 4335F10

Rabi Rice 2746 3560 5163 4141 5314 6643 5476 5736 5176-S 5398 - 3718F10

Jabalpur Soybean 619 733 1403 1293 1533 1645 1373 1749 1398-S 1395 - -

Wheat 1448 2189 4239 3670 4602 5036 4466 5144 4352-S 4399 - -

Denotation

F= 50% NPK + 10 t ha-1 FYM at Junagadh, F10 = FYM 10 t ha-1 at Jagtial, F20 = FYM 20 t ha-1 at Udaipur, F25 = FYM 25 t ha-1 at Junagadh, BF= Biofertilizer alone, R= 50% NPK+ Rhizobium, A= 100% NPK+ Seed treatment with Azotobacter, GM= 50%NPK+ Green Manuring at Raipur, BGA= 50%NPK+ BGA at Raipur, +S= 100% NPK(+S) at , -S= 100% NPK(-S), STCR= NPK as per soil test.

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SOIL QUALITY

To sustain the productivity consistently over the year,s maintenance of soil health is most essential. In LTFE, the soil characteristics (chemical, physical and biological) are monitored regularly and the results obtained are discussed in this section.

Soil pH

Analysis of Alfisols of Banglore revealed that application nitrogenous fertilizer irrespective of combination of other nutrients resulted decline in soil pH. The magnitude of decline in soil pH increase with increase in rate of N application (Fig. 1). Application of N alone resulted in maximum decline in soil pH. But incorporation of FYM maintained the soil pH at same level as it was at onset of experiment However, addition of lime improved the soil pH. It is interesting to note an improvement in soil pH in control plot. The decline in soil pH on application of N is probably due to acidity created by urea and the sustaining soil pH on application of FYM is due to increase in buffering capacity of soil. Similar effect of fertilizer application on soil pH was also recorded at Palampur and Ranchi. However, magnitude of decline was largest at Palampur minimum at Pattambi and Bhubneshwar. Except Pantnagar decline in soil pH on application of fertilizer was noted but decline was of very low magnitude. However, at Pantnagar improvement is soil pH was recorded on application of fertilizer.

Electrical Conductivity

The electrical conductivity gives an idea about the salt content in soil solution. Though almost in all the soils, slight increase in EC (Fig. 2) with respect to initial level was recorded which is due to addition of fertilizers in the soils but the increase in EC is not to the extent which could have any adverse effect on soil health and plant growth

Soil Organic Carbon (SOC)

Soil Organic carbon (SOC) is the key soil property which indicates the fertility status of a soil. The data recorded (Fig. 3) on SOC from the experiments being conducted at different locations with various cropping system under LTFE revealed that balanced application of nutrients resulted increase in SOC at all the places except at Pantnagar, Barrackpur and Udaipur and to some extent at Ranchi. At Ranchi only in NPK+FYM treatment SOC was maintained at par with initial level and in all other treatments depletion in SOC was recorded in spite of being soybean wheat cropping system. In Alfisols of Palampur, Bangalore, Pattambi and Bhubneshwar the balanced application of nutrients (NPK, NPK+FYM) resulted in increase in soil organic carbon (Fig. 3).

Mollisols of Pantnagar and Inceptisols of Barrackpur are exceptions where application of fertilizer nutrients resulted decline in SOC compared to the initial SOC inspite of higher productivity and addition of relatively larger amount of biomass. The soils of Pantnagar were put into cultivation recently and the organic carbon was not in steady state of equilibrium. Cultivation of soil and application of fertilizer enhanced the rate of oxidation of easily oxidizable organic matter which has caused decline in SOC. Maintenance of SOC under FYM+NPK was obviously due to addition of additional amount of carbon though FYM. Almost similar situation existed at Barrackpore also.

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Thus, the data generated under LTFE at different centre disproved the notion that application of fertilizer and cultivation of soil reduced the SOC. The conjunctive use of chemical fertilizer and FYM always maintained relatively larger amount of SOC compared to only chemical nutrients use. This particular treatment even maintained SOC at Pantnagar also. Thus the use of chemical fertilizer should not be blamed for decline in SOC. Decline in SOC was noticed only on application of chemical nutrients in either imbalanced form i.e. N or NP or in less quantity which did not return enough amount of crop residue to soil.

0.0

2.0

4.0

6.0

8.0

10.0

Bangalore Jabalpur Barrackpore Ranchi Ludhiana Pantnagar

pH

Initial Control N NP

50% NPK NPK 150% NPK NPK+ FYM

NPK+ Lime / Zn NPK(-S) NPK+ HW/ STCR/ Azola

0.0

2.0

4.0

6.0

8.0

10.0

Palampur Junagadh Udaipur Raipur Jagtial Bhubanesw ar Pattambi

pH

Initial Control N NP

50% NPK NPK 150% NPK NPK+ FYMNPK+ Lime / Zn NPK(-S) NPK+ HW/ STCR/ Azola

Fig. 1 The soil pH under LTFE treatments as influenced by nutrient management at different centres

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0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

Bangalore Jabalpur Ludhiana Pantnagar Junagadh

EC

(d

S m

-1)

Initial Control N NP

50% NPK NPK 150% NPK NPK+ FYM

NPK+ Lime / Zn NPK(-S) NPK+ HW/ STCR/ Azola

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

Udaipur Raipur Jagtial Bhubanesw ar

EC

(d

S m

-1)

Initial Control N NP50% NPK NPK 150% NPK NPK+ FYMNPK+ Lime / Zn NPK(-S) NPK+ HW/ STCR/ Azola

Fig. 2 The soil EC (dSm-1

) under LTFE treatments as influenced by nutrient management at different centres

15

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

18.0

Bangalore Jabalpur Barrackpore Ranchi Ludhiana Pantnagar Palampur

SO

C (

g k

g s

oil

-1)

Initial Control N NP

50% NPK NPK 150% NPK NPK+ FYMNPK+ Lime / Zn NPK(-S) NPK+ HW/ STCR/ Azola

0.0

5.0

10.0

15.0

20.0

25.0

Junagadh Udaipur Raipur Jagtial Bhubanesw ar Pattambi Akola

SO

C (

g k

g s

oil

-1)

Initial Control N NP

50% NPK NPK 150% NPK NPK+ FYMNPK+ Lime / Zn NPK(-S) NPK+ HW/ STCR/ Azola

Fig. 3 The soil OC (g kg-1

) under LTFE treatments as influenced by nutrient management at different centres

In Inceptisols of Ludhiana, Raipur, New Delhi, Coimbatore, Jagtial, and Junagarh increase in SOC was recorded under balanced application of nutrient. The intensive cropping and the returning of more crops biomass through stuble, root and leaf to soil resulted in little larger increase in SOC. For example, at Jabalpur soybean-wheat system, in all the treatments including control increase in SOC was recorded compared to initial SOC. But at other places imbalanced use of nutrients or application of nutrients in less quantity (50% NPK) resulted decline in SOC. Incorporation of crop residue in less quantity as a result of low productivity under imbalanced nutrient application is the reason for decline in SOC.

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Soil Biological Properties

Soil microorganisms play important role in transformations of nutrient from unavailable to available form and vice-versa. Therefore, for maintaining equilibrium of nutrients in soil a good environment for the growth of microorganism is essential. The quality of environment is dependent on management practices, soil moisture and soil temperature, toxic element etc. The effect of management practices on biological properties of soil of different centres is given in this section.

1. Ranchi

The data depicted in Table 2 revealed that there is increase in soil respiration as we moved from imbalance use of nutrients (N) to balanced use of nutrient (NPK). It is interesting to note that application of lime resulted in sharp increase in soil respiration. Probably application of lime resulted in improvement in soil conditions which are conducive to growth of microbial biomass. The maximum rate of soil respiration in NPK+FYM treatment (after 35 years) is obviously and due to additional application of carbon, which helps in improving the soil conditions favorable to microbial growth. The data on soil microbial biomass N, P, K and S also followed almost similar trend. A trend similar to that of carbon of activities of three soil enzymes viz. dehydrogenase, phosphatase and urease were also observed. However, there was no definite pattern in case of phosphatase.

Table 2. Effect of continuous cropping and fertilization on some of biological properties of soil at Ranchi

2. Bangalore

Microbial biomass C and N: The Microbial biomass carbon (MBC) and microbial biomass N (MBN) contents of soil are important to assess soil fertility status. Both biomass of C and N of soil are very good indicators of the microbial activity as well as mineralization of C, N and release of other nutrient elements in to the soil solution from the organic components of soil. In, 100% NPK + FYM and 100% NPK + FYM + lime treatments, biomass C content recorded was of the tune of

Treatments CO2 evolution

(mg per 100 g

-1 soil)

SBMC (ppm)

SBMN (ppm)

SBMP (ppm)

SBMS (ppm)

Dehydrogenase activity (µh

Formazon g-1

soil)

Phosphatase activity (µh phenol

g-1 soil h

-1)

Urease activity (µh urea N

hydrolysed g-1

soil h-1

Control 32.71 176.2 16.4 1.37 1.27 12.27 164.3 9.80

100% N 32.41 129.4 10.1 1.13 1.55 7.56 148.8 7.42

100%NP 38.82 153.4 13.8 4.79 3.5 13.90 194.3 12.19

100% NPK 39.87 189.6 18.5 7.05 4.5 12.05 185.3 12.58

100%NPK+Lime 48.48 213 21.8 8.44 3.4 18.70 162.5 13.56

100%NPK+FYM 60.11 231.3 24.0 10.21 6.8 23.73 308.0 16.98

CD (P=0.05) 7.39 12.2 2.8 0.84 0.61 1.87 10.13 2.38

17

265 and 271 mg g-1 and the biomass N was 30.9 and 31.6 mg g-1 soil, respectively. These values were significantly larger than those recorded under control treatment which were 174 and 20.3 mg g-1, respectively. (Table 4.5)

Enzyme activity: The activities of both enzymes studied, i.e., acid phosphatase and dehydrogenase were significantly influenced by the addition of FYM as well as fertilizers probably because of increase in the incorporation of crop residues as a result of larger yield. The highest

acid phosphatase activity was recorded in 100% NPK+FYM (91 5 µg PNP g-1day-1) whereas the

lowest activity was recorded in 100% N (80.8 µg PNP g-1day’). Application of lime did not significantly influence the acid phosphatase activity. However, incorporation of both FYM and lime resulted in enhancement of dehydrogenase activity of soil. The maximum dehydrogenase activity

(54.1 µg PNP/g 24 hrs) was recorded in 100% NPK+ FYM+ lime (superimposed) follwed by 100%

NPK + FYM. However, the lowest dehydrogenase activity was recorded in 100% N (34.5 µg PNP g-1 24 hrs-1).

Table 3. Effect of long-term fertilization and cropping on microbiological properties at Banglore

3. Palampur

The data on microbial population (Table 4) counts revealed that in all the treatments, except 100% N and 100% NP treatment resulted increase bacteria population. The largest population of bacteria was recorded in NPK+FYM treatment. But increase in nutrient application from 50 to 150% resulted decline in population whereas the reverse was noted in case of population of fungi. It is strange to note that application of FYM resulted in decline in fungi population. The population of Actinomycetes and Azotobacter were also adversely affected with increase in the amount of nutrients application whereas, incorporation of FYM along with fertilizer resulted in increase in Actinomycetes and Azotobacter.

Treatment Biomass C

(µg/g)

Biomass

N(µg/g)

Acid phosphatase

(µg/PNP/g/24h)

Dehydrogenase

(µg/PNP/g/24h) 50% NPK 206 26.4 85.0 40.7 100% NPK 212 24.7 87.3 42.7 150% NPK 200 23.3 88.3 45.9 100% NPK+HW 219 25.6 86.8 43.1 100% NPK +lime 208 24.3 81.6 44.6 100% NP 189 22.1 84.1 36.6 100% N 184 21.6 80.8 34.5 100% NPK+FYM 265 30.9 91.5 51.6 100% NPK(S- free) 205 23.9 84.4 43.3 100% NPK+FYM+lime 271 31.6 82.2 54.1 Control 174 20.3 82.5 40.6 C.D. at 5% 8.2 1.360 3.421 3.912

18

Table 4. Microbial counts as affected by different nutrient management options under LTFE at Palampur

Thus the results on microbial population studies at Palampur indicated decline in populations of actinomycetes, bacteria and azotobacter with increase in fertilizer nutrient application. But increase in the population of these microorganisms was recorded on incorporation of FYM even in presence of fertilizer whereas, reverse was observed for population of fungi.

Though application of FYM resulted in decline in fungi but incorporation of FYM resulted increase in phosphate solubilizers which are mostly fungi (Table 5). However, proportion of PSB is very meager only 3 to 7 percent compared to fungi. The balanced application of nutrients resulted increase in population of P solubilizing fungi also.

Table 5 Effect of different nutrient management options on activity of Phosphate Solubilizing Organisms

Percent Phosphate Solubilizing Microorganisms

Treatments Fungi Bacteria

50% NPK 11.06 3.73 100% NPK 19.70 6.06 150% NPK 34.96 7.96 100% NPK + HW 81.40 3.53 100% NPK + Zn 88.90 4.90 100% NP 35.70 7.00 100% N 46.93 3.50 100% NPK+FYM 62.63 4.16 100% NPK(-S) 39.63 3.66 100% NPK+ Lime 41.46 4.10 Control 22.73 2.20

Among the phosphatase enzymes, the largest activity recorded was of Acid phosphatase followed by Alkaline phosphatase and phosphodiesterase (Table 6). Perusal of data indicated that the maximum activities of all the three enzymes FYM+NPK treatment. Otherwise as such there is no visible effect of treatment on the activities of these enzymes.

Treatments No. of Bacteria

(CFU Χ 105/g soil)

No. of Fungi (CFU Χ 10

4/g soil)

No. of Actinomycetes (CFU Χ 10

3/g soil)

No. of Azotobacter (CFU Χ 10

3/g soil)

50% NPK 24.56 4.39 52.40 55.16 100% NPK 11.49 7.83 20.30 17.50 150% NPK 6.94 8.06 5.75 14.61 100% NPK + HW 9.21 5.75 12.10 68.53 100% NPK + Zn 18.23 2.61 8.86 15.93 100% NP 7.96 5.13 24.33 45.50 100% N 4.55 6.98 46.33 11.86 100% NPK+FYM 28.08 2.78 73.20 226.16 100% NPK(-S) 13.76 5.04 34.63 14.6 100% NPK+ Lime 18.88 0.45 87.86 92.66 Control 9.53 4.45 19.76 127.83

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Table 6. Effect of different nutrient management options on activities of Phosphatases at Palampur

Treatments Alkaline phosphatase

(µg p-nitrophenol g-¹ h

-¹)

Acid phosphatase (µg p-nitrophenol g

-¹ h

-¹)

Phosphodiesterase (µg p-nitrophenol g

-¹ h

-¹)

50% NPK 63.69 393.54 27.97 100% NPK 75.20 443.54 33.78 150% NPK 65.48 448.22 34.29 100% NPK + HW 76.63 424.84 38.08 100% NPK + Zn 61.17 482.03 36.56 100% NP 64.40 402.17 29.46 100% N 54.33 371.24 21.91 100% NPK+FYM 123.58 608.11 55.25 100% NPK(-S) 66.92 418.54 27.97 100% NPK+ Lime 81.67 447.86 46.91 Control 57.21 390.66 23.93

Superimposition of Treatments

Due to continuous application of P in excess to uptake of crop resulted built up in soil P. The build up of P though so far did not have any ill effect on crop growth but increased the cost of cultivation. In another situation application of K in inadequate quantity continuous absence of K in fertilizer schedule in some of the treatments resulted in decline in crop productivity. Under these situations full potential of crop is not harnessed. Therefore, to explore the possibility to utilize the build up P and to overcome the decline in yield due to inadequate supply of K or other nutrients like Zn and S, superimposition in some of the treatments was done at few centres. The results obtained are described in the following section.

1. Bangalore

At Bangalore 4 treatments were splitted as per the details given in Table 7. To explore the possibility of breaking yield plataue, 150% NPK treatment was supper imposed with 5 and 10 t FYM ha-1 additionally. The results indicated that application 5 t FYM over and above 150% NPK resulted in marginal increase in the yield of maize. Whereas reduction in P dose by half and superimposition of 5t FYM in 100% NPK resulted increase in yield from 3.97 t ha-1 to 4.1 t ha-1 and additional application of lime did not have significant improvement in yield compare to yield obtained in original NPK treatment.

In 100% NP treatment crop was suffering from inadequate supply of K and simultaneously there is built of soil P. The reduction in P dose by half and application of 100% K resulted nearly 10 fold increase in yield of finger millet from 0.42 t ha-1 to 3.59 t ha-1 and maize yield from 0.17 t ha-1 to 1.9 t ha-1. However, additional application of lime did not have any effect on yield of either finger millet or maize. Similarly on superimposition of FYM along with P and K in 100%N treatment resulted increase in yield of finger mille from 0.33 t ha-1 to 3.4 t ha-1 and maize yield from 0.07 t ha-

1 to 1.7 t ha-1. Here also additional application of lime did not increase yield of any crop significantly.

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Table 7. Grain and straw yield (q ha-1

) of finger millet (Kharif 2005-06) and maize (Rabi 2004-05) in superimposed treatments

Finger millet Hybrid Maize Treatments

Grain Straw Grain Straw T3 (2005 kharif onwards)

150% NPK 45.30 67.80 150% NPK, 5t/ha FYM 46.44 68.45 150% NPK, 10t/ha FYM 45.93 72.86

T4 (2002 kharif onwards) 100% NPK 39.78 61.60 20.33 39.83 100% N, 50%P, 100% K, FYM 41.28 64.26 20.76 39.62 100% N, 50%P, 100% K, FYM, lime 40.57 60.89 20.80 39.43

T6 (2002 kharif onwards) 100% NP 4.26 10.04 1.74 3.67 100% N, 50%P, 100% K, FYM 35.94 58.25 19.01 35.39 100% N, 50%P, 100% K, FYM, lime 35.98 55.97 19.06 37.09

T7 (2002 kharif onwards) 100% N 3.35 5.79 0.76 1.41 100% NPK, FYM 34.14 61.02 17.05 33.51 100% NPK, FYM, lime 35.81 66.00 17.27 33.88

Plate 3 Supperimposition in 100% N and 100% NPK in maize at Bangalore

100% N NPK+5 t FYM supperimposed in N

100% NP(1/2)K+5 t FYM supperimposed in 100% NPK

NPK+5 t FYM +lime supperimposed in N

21

2. Ranchi

At Ranchi superimposition of lime in NP treatment did not increase yield of soybean significantly (Table 8). However, incorporation of FYM resulted increase in yield of soybean from 3.33 q ha-1 (100%NP) to 18.2 q ha-1 Where as in wheat application of lime resulted significant increase in yield from 38.1 q ha-1to 45.2 q ha-1 and application of FYM further increased the wheat yield to 51.74 q ha-1. Superimposition of lime and FYM in 100%N treatment resulted in increase in yield of soybean from 0.85 to 7.75 and 15.9 q ha-1, respectively. Though increase in yield of wheat was also recorded but was of very low magnitude. Probably insufficient availability of P and K in wheat seems to be the reason for low productivity whatever increase in yield of wheat was recorded was due to little supply of these growth limiting nutrients (P and K) though FYM and moderation of soil condition due to lime or FYM. Table 8 Effect of lime/FYM on Average Grain Yield (q ha

-1) of wheat in superimposed treatment in 2002-03

and 2003-04 at Ranchi (2002-03 and 2003-04)

Average Grain Yield (q ha-1

) Treatments

Soybean Wheat

100% NP (Original) 3.33 38.1 100% NP + lime 4.18 45.2 100% NP + FYM 18.2 51.7 100% N (Original) 0.85 1.44 100% NP + lime 7.75 5.4 100% N + FYM 15.9 6.4 100% N (S) PK* (Original) 4.2 9.88 100% N (S) PK+ lime 16.5 27.2 100% N (S) PK+ FYM 16.1 25.1 C.D. 5% 17 3.1 *N was supplied through ammonium sulphate

At Ranchi LTFE has got one treatment in which N is supplied through ammonium sulphate which adversely affected the soil productivity. The application of both lime and FYM had tremendous positive effect on seed yield of soybean and grain yield of wheat (Table 7.2) as well. Since in this treatment P and K were available in adequate quantity as both were being supplied continuously and application of amendments made availability of both the limiting nutrients by moderating the soil conditions. At Ranchi though lime has resulted increase in yield but was effective only when P and K were applied whereas application of FYM is always effective amendment and proved to be better than lime under all situations. The results proved that FYM is better amendment in Alfisols compared to lime.

The results of superimposition of treatment indicated that in Alfisols reduction in P dose did not have any adverse effect on yield of finger millet and maize. Addition of K in N P and superimposition of P and K in 100%N treatment resulted in very large increase in yield of both F. millet and maize. Farm yard manure (FYM) was found better off amendment i.e. lime

3. Ludhiana

At Ludhiana increase in N to 100% and reduction of P to half in 50% NPK treatment resulted increase in yields of both maize and wheat and superimposition of Zn further led to increase in yields of both maize and wheat (Table 9). However, curtailment in dose of P to half in 100% NPK

22

and one third in 150% NPK resulted in decline in yield of maize but was non significant but did not have any adverse effect on wheat yield even after 10 years. This indicates that P stock build up in last 25 years is not sufficient to meet out P requirement for 10 years. To get the potential yield one has to keep on eye on P status and whenever soil P status goes down P must be applied.

The results at Ludhiana clearly showed that curtailment of P dose to half from optimal and super optimal doses did not have any adverse effect on yields of both maize and wheat. However, to get potential yield of both maize and wheat Zn application is essential and eye on P status in soil. The farmer must keep an eye on P status in soil to get sustainable yield.

Table 9 Effect of different levels of fertilizers on crop yield (t ha-1

) of maize (2003) & wheat (2003-04) at Ludhiana

Treatment

Maize Wheat

NPK(Original) S1 50% NPK 2.41 3.66 S2 100% N 50% PK 3.26 4.21 S3 100% N 50% PK + Zn 3.31 4.48 100% NPK (Original) S1 100% NPK 3.77 4.25 S2 100% N 50% P 100% K 3.37 4.20 S3 100% N 50% P 100% K + Zn 3.46 4.33 150% NPK S1 150% NPK 3.76 4.85 S2 150% N 50% P 150% K 3.13 4.98 S3 150% N 50% P 150% K + Zn 3.46 4.97 100% NPK- S S1 100% NPK(S) 3.24 4.78 S2 100% NK 3.69 3.97 S3 100% N + Zn 3.71 4.89

4. Pantnagar

From the LTFE data of Pantnagar it was learnt that Zn and S are the yield limiting nutrients in addition to N. To sustain the yield at high level, 100% NPK and 150% NPK treatments were superimposed with Zn, S, S+ Zn and FYM. Data presented in Table 10 revealed that application of both Zn and S either singly or conjunctively resulted increase in yield of rice. Though superimposition of both Zn and S did not increase the rice yield significantly during 2004 but there has been significantly increase in yield of rice on combined application of S and Zn. Additional application of FYM further resulted increase in yield of rice to the tune of 2-3 q ha-1 over the S + Zn.

Perusal of yield data of wheat (2004-05 and 2005-06) recorded on superimposition of S, Zn and FYM revealed that in both the years application of S over and above 100 or 150% NPK did not show any effects on wheat yield. But application of Zn during kharif resulted significant increase in yield of wheat. Data further revealed that incorporation of FYM over and above 100% NPK+ Zn + S resulted increase in yield of wheat in both the years. Though increase in yield is not be significant statistically may be because of less number of replications.

23

Thus the results confirmed that Zn and S are yield limiting nutrients at Pantnagar. To sustain the yield of rice-wheat system at higher level over a period of time, application of Zn and S are essential in additional to NPK.

Table 10. Rice and Wheat yield as affected by superimposition of Zn & S at Pantnagar

2004-05 2005-06

100% NPK 150% NPK 100% NPK 150% NPK

Treatment

RICE

S1 100% NPK 49.75 52.75 44.60 42.90 S2 100% NPK+S 53.00 55.50 46.00 43.60 S3100% NPK-S+Zn 55.50 58.00 49.20 50.40 S4 100% NPK+S+Zn 58.75 60.50 51.00 53.40 S5100% NPK+S+Zn+FYM 60.25 61.75 53.70 56.20 CD (5%) 9.61 2.95

WHEAT S1 100% NPK 34.25 34.00 34.00 34.90 S2 100% NPK+S 36.50 34.75 35.50 35.80 S3100% NPK-S +Zn 37.75 35.25 43.50 45.502 S4 100% NPK + S +Zn 38.50 36.25 45.35 47.30 S5100% NPK+ S+ Zn+FYM 39.75 38.00 48.00 48.70 CD (5%) 3.97 3.16

Demonstration of Technology: Satellite Experiments

To evaluate technologies generated from LTFE and to develop the strategy for enhancing the productivity of the region by intervening the management practices few centres have conducted experiments on farmer’s field. The purpose of conducting the demonstrations experiment was to educate the farmer about judicious and balance use of nutrients. Survey conducted by the centres revealed that majority of the farmers are using N alone and some of the farmers are using N and P through external source of nutrients. Due to continuous use of phosphatic fertilizer there has been built up in soil P like in LTFE plots. To exploit the built up P in soil, experiments were conducted.

1. Bangalore

The results of the experiment conducted at Verammanahally village on maize revealed that reduction of P doses to half did not have adverse effect on yield whereas increase in K dose to double resulted increase in yield of maize from 37.9 q ha-1 (100% NPK) 48.6 q ha-1 (Table 11). Incorporation of lime did not show any improvement in productivity. However, incorporation of 5 t FYM resulted in increase in maize yield significantly. The similar trend was also recorded on grain yield of finger millet. Contrary to the effect lime in maize, a positive effect of lime on grain yield of finger millet was not seen. This suggests that phosphorus dose can be reduced safely and the diversion of the money saved equivalent to half dose of P to K would fetch more benefit to farmers.

24

Table 11. Evaluation of alternate strategies of fertilizer use on their impact on nutrient management

Maize Finger millet Treatments

Grain yield (q ha-1)

FRR (yield /kg fertilizer)

Grain yield (q ha-1)

FRR (yield /kg fertilizer)

Control (NPK) 37.92 6.84 34.00 6.13 N ½ P K 37.44 9.86 34.60 9.74 N ½ P 2K 48.61 7.54 35.00 8.22 N ½ P K + lime 48.61 6.23 36.00 11.18 N ½ P K + 5 t FYM 51.33 10.67 39.80 10.14 FRR= Fertilizer response ratio

To evaluate the nutrient response ratio in most sustainable nutrient management option of LTFE and to compare with the farmer’s practice field experiments were conducted on farmer’s field in Kolar, Tumkur and Madenahalli districts of Karnataka. The results obtained (Table 8.1) revealed that though the maximum yields of maize (45.2 q ha-1) was recorded on application of 150% NPK but the response ratio was least (Table 12). The largest nutrient response ratio (kg grain/kg nutrient) was obtained on application of 100% NPK+ 15 t FYM in both the crops. Though the second largest yield of finger millet was recorded under farmer practice but the response ratio was poorest. The largest yield in 150% NPK indicated that to sustain the productivity at higher level K should be added in larger quantity.

This results at farmers field clearly indicated that the P dose can be reduced to half safely without any reduction in yield. But to enhance the productivity, K is needed in more quantity and part of that could be supplemented through FYM. To harness greater nutrient utilization efficiency integrated use of chemical fertilizer with FYM is a better option.

Table 12: Evaluation of efficiency of most sustainable fertilizer use practices

Maize Finger millet Treatments

Grain yield (q ha

-1)

FRR (yield /kg fertilizer)

Grain yield (q ha

-1)

FRR (yield /kg fertilizer)

150% NPK 45.20 14.08 37.00 15.04 100% NPK + FYM@ 15 t/ha 42.10 19.67 27.50 16.77 Package of practice 37.72 17.46 25.50 15.55 Farmers practice 40.83 18.77 22.00 8.76 Control 100% NPK 37.92 17.72 26.00 15.85 Package of practice = 100% NPK+ 10t FYM, Farmers practice = 64 kg N + 46 kg P FYM (15-20 t ha

-1) ; FRR= Fertilizer

response ratio

2. Ludhiana

To assess the soil fertility status of farmers fields of nearby district and to compare and simulate with the management options of LTFE, soil sample from Ludhiana, Bathindia and Gurdaspur districts of Punjab were collected and analysed for fertility status. To evaluate the nutrients management strategies developed out of LTFE results, farmer’s field were selected for conducting field. Field experiments were conducted with 9 Treatments as per the details given in Table 13 with maize-wheat system in three villages. The results obtained indicated that reduction

25

in P dose to half resulted decline in yield significantly at some of sites compared to 100% P. However, application of Zn resulted increase in yield of both maize and wheat at all the sites. Critical evaluation of data further indicated that conjunctive use of chemical fertilizer and FYM resulted in highest productivity at all the site. The yield obtained was even larger than the yields obtained on application of nutrient on soil test basis. Decline in yield (may not be statistically significant) of maize and wheat on reduction in dose of P indicated that still the built up P is not sufficient enough to curtail the P dose at farmers field.

Thus, results clearly indicated that application of P and Zn is essential to harness the potential productivity of crops. But to sustain the productivity at higher level conjunctive use of chemical fertilizer and FYM is the only option. This supports the strategies developed out of LTFE results.

Table 13. Effect of organic and inorganic fertilizer on grain yield (t ha-1

) in maize-wheat cropping system in different agro-ecological zones

Farmers’ practice = 150 kg N + 45 kg P2O5 + 0 kg K2O to Maize and 150 kg N + 60 kg P2O5 + 0 kg K2O to Wheat

3. Akola

To evaluate the strategies developed out of the results of LTFE were evaluated by conducting field experiment at 6 farmer’s fields in 5 villages using soybean-wheat as test cropping system. The results recorded revealed that Zn and S are essential to harness the potential yield in addition to N, P and K. Application Zn + S over and above NPK resulted increase in soybean yield from 11.1 q ha-1 to 14.12 q ha-1 and wheat yield from 27.6 q ha-1 to 33.1 q ha-1 (Table 14). The result further revealed that the conjunctive use of NPK+FYM resulted in highest productivity of both soybean and wheat. The decline in yield under farmer’s practices was obviously due to imbalance use of nutrients and P application in less quantity in both soybean and wheat as well.

Thus from field experiment it is concluded that to sustain the productivity of soybean-wheat Zn and S are essential in Akola region of Maharashtra. But to sustain the productivity at higher level and sustain over a long period of time integrated use of fertilizer and FYM is essential.

Jhaloa Ramgarh Rajewal Treatment

Maize Wheat Maize Wheat Maize Wheat

100%N 50%PK 3.65 4.70 3.83 4.07 3.67 4.42 100%NPK 50%Zn 4.06 5.28 4.47 4.53 4.63 4.73 100%NPK 4.00 5.50 4.40 4.55 4.36 4.95 100%NPK+FYM 4.53 5.97 5.00 5.19 5.33 5.41 Farmers’ practice 3.72 5.05 4.13 4.11 4.10 4.41 Soil Test basis 4.12 5.30 4.43 4.69 4.57 4.80 Control 1.99 3.12 2.01 2.59 1.76 2.67 CD 5% 0.39 0.42 0.47 0.45 0.42 0.44

26

Table 14. Yield of soybean and wheat at Akola as influenced by various treatment (q/ha) 2005-06

Av.6 Expts.)

Soybean Wheat Treatment

Grain Straw Grain Straw

RD NP 11.17 14.20 27.69 36.22 RD NPK + Zn 12.19 15.37 29.66 38.82 RD NPK + S + Zn 14.12 17.80 33.15 43.36 RD NPK + 10 t FYM ha

-1 + Zn 16.79 21.18 37.61 48.77

Farmers practice 50:25 9.35 11.79 24.49 32.07 SE (m) ± 0.24 0.33 0.73 0.92 CD at 5% 0.67 0.94 2.06 2.60 RD for soybean N-30, P-75, K-0, Wheat N-120, P-60, K-60, Zn 2.5 kg ha

-1, S-40

YIELD SUSTAINABILITY As discussed earlier, a drastic decline in crop productivity has been observed since few years after the inception of the experiment in Alfisol due to continuous imbalance nutrient use, either N alone or NP. The superimposition of P, K and FYM in 100% N treatment (original) resulted in quantum jump in yield from 5 to 31.06 q ha-1 in finger millet and 0.8 to 16.8 q ha-1 in maize at Bangalore (Table 15). However, application of lime over and above 100% NPK + FYM did not have any additional beneficial effect on yield of both the crops. Similarly, in 100% NP treatment, reduction in P dose and addition of K and FYM also increased the productivity of both the crops. Here, in this treatment also application of lime over and above 100% NK + 50% P + FYM did not show any beneficial effect on yield. Thus, results of superimposed treatment clearly brought out that for sustaining the productivity application of K, P, S and FYM is must. An eye on P status must be kept to avoid unnecessary built up of P. This would not only curtail expenditure on P but also minimize water pollution. The grater sustainability yield index (SYI) of all the crops (Table 2) in NPK+FYM/lime treatment is again supports the finding that to enhance and to sustain the productivity application of FYM/lime is essential along with balanced nutrition. FYM not only act as ameliorating agent but also rule out the possibility of hidden hunger of micro- and secondary nutrients. Whereas, application of lime also acts as an amendment and creates a conducive environment in root zone which facilitate plant root growth and availability of nutrients by controlling the soil pH. Table 15. Sustainable Yield Index (SYI) for various treatments in Alfisols of Bangalore and Ranchi in

long-term experiments

Location / Crops Control N NP NPK NPK+FYM NPK+ Lime

Bangalore

Fingermillet 0.06 0.07 0.09 0.53 0.62 0.53

Maize 0.00 0.00 0.00 0.41 0.55 0.51

Ranchi

Soybean 0.14 0.02 0.21 0.47 0.62 0.61

Wheat 0.05 0.02 0.21 0.31 0.37 0.35

27

TECHNOLOGY GENERATED

• In Alfisols (acid soils) the K was found to be most limiting nutrients and to sustain productivity K application along with FYM/Lime is essential

• Phosphorus dose can be reduced safely and the diversion of the money saved equivalent to half dose of P to K or other input would fetch more benefit to farmers.

• To get potential yield in Indo-gangatic Plains (IGP) S and Zn are essential in addition to major nutrient application

• To sustain the productivity of soybean-wheat Zn and S are essential in Akola region of Maharastra.

FUTURE THRUST Since monitoring of soil quality and sustainability is the major objective of the project. Unlike air and water we do not have definite key soil quality attributes for assessing the soil quality. Therefore future thrust would be on

• Identification of soil indicators sensitive to management practices and responsible for sustainability.

• Assessment of soil quality index (SQI) under different management practices and cropping systems.

• Organic pools and dynamics of carbon, nitrogen, phosphorus, potassium and micronutrients in soil needs investigations to understand their contribution on soil quality and crop productivity.

• Investigation on effect of long-term use of organic and inorganic fertilizers on carbon sequestration in soils for improving soil quality and environment

28

AWARD

29

WORKSHOP ORGANIZED

IISS BHOPAL (JANUARY 17-18, 2007)

PAU LUDHIANA (NOVEMBER 6-8, 2004)

30

PUBLICATIONS RELEASED

Publications Released by Honourable DDG, Dr JS Samra, Dr PD Sharma (ADG, Soils) and Vice Chancellor PAU Dr KS Aulakh at Workshop held at PAU Ludhiana

(November 6-8, 2004)

31

LANDMARK PUBLICATIONS (AICRP LTFE)

*********

NOTE

DATE : JULY 04, 2009 Please find enclosed herewith the salient findings of LTFE (Including data) for display on the Institute website.

(Muneshwar Singh) Project Coordinator (LTFE)

IISS, Bhopal The Director, IISS, Bhopal

NOTE

DATE : JULY 04, 2009 Please find enclosed herewith the salient findings of LTFE (Including data) for display on the Institute website.

(Muneshwar Singh) Project Coordinator (LTFE)

IISS, Bhopal The Director, IISS, Bhopal