Effect of organic nitrogen sources and biofertilizers on production potential and energy budgeting of rice (Oryza sativa)-based cropping systems
DOI:
https://doi.org/10.59797/ija.v58i4.4246Keywords:
----Abstract
A field experiment was conducted during 200506 and 200607 at Varanasi, Uttar Pradesh, to find out the ef- fect of organic nitrogen sources and biofertilizers on system productivity and energy budgeting of rice ( Oryza sa- . tiva L )-based cropping system. Ricepotato [ Solanum tubersoum (L.)]onion [ Allium cepa (L.)] system recorded significantly higher production efficiency (97.5 kg/ha/day), land-utilization efficiency (91.4%), economic efficiency ( 738/ha/day), energy input (61.08103MJ/ha) and energy output (187.09103MJ/ha). The lowest (39.4 103MJ/ ha) energy intensiveness was recorded in ricetable pea ( Pisum sativum var. hor tense)cowpea [ Vigna unguiculata (L.) Walp.] cropping system. However, the organic nutrition with biofertilizers ( Azotobacter and phos- phate-solubilizing bacteria) had the highest rice-equivalent grain yield (35.3 t/ha), production efficiency (96.7kg/ha/ day), land utilization efficiency (89.8%), economic efficiency (803 ha/day) and energy-use efficiency (3.15) of sys- tem, followed by organic nitrogen sources alone (3.0). Recommended dose of N @100% through organic nitrogen sources alone was the next best treatment resulting in higher productivity and system efficiency. Rice-potato-on- ion cropping system was found most productive, profitable and energy efficient with application of 100% recom- mended dose of nitrogen through organic sources along with biofertilizers.References
Indian Journal of Agronomy 58 (4): 459__464 (December 2013)
Research Paper
Effect of organic nitrogen sources and biofertilizers on production potential and energy budgeting of rice (Oryza sativa)-based cropping systems
S.K. YADAV1, SUBHASH BABU2, Y.SINGH3, G.S.YADAV4, KALYAN SINGH5, RAGHAVENDRA SINGH6 AND
HARVIR SINGH7 Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh 221 005
Received : January 2012; Revised accepted : October 2013
A field experiment was conducted during 200506 and 200607 at Varanasi, Uttar Pradesh, to find out the effect of organic nitrogen sources and biofertilizers on system productivity and energy budgeting of rice (Oryza sativa L.)-based cropping system. Ricepotato [Solanum tubersoum (L.)]onion [Allium cepa (L.)] system recorded significantly higher production efficiency (97.5 kg/ha/day), land-utilization efficiency (91.4%), economic efficiency (
/ha/day), energy input (61.08103MJ/ha) and energy output (187.09103MJ/ha). The lowest (39.4 103MJ/ ha) energy intensiveness was recorded in ricetable pea (Pisum sativum var. hortense)cowpea [Vigna unguiculata (L.) Walp.] cropping system. However, the organic nutrition with biofertilizers (Azotobacter and phosphate-solubilizing bacteria) had the highest rice-equivalent grain yield (35.3 t/ha), production efficiency (96.7kg/ha/ day), land utilization efficiency (89.8%), economic efficiency (803 ha/day) and energy-use efficiency (3.15) of system, followed by organic nitrogen sources alone (3.0). Recommended dose of N @100% through organic nitrogen sources alone was the next best treatment resulting in higher productivity and system efficiency. Rice-potato-onion cropping system was found most productive, profitable and energy efficient with application of 100% recommended dose of nitrogen through organic sources along with biofertilizers.
Key word : Biofertilizers, Crop production, Energy, Rice-based cropping systems, Organic N sources
In India agriculture not only provides food for all, but also gives employment to 50% of the total workforce. The production systems developed and adopted during green revolution were explorative and natural resources like soil and water were subjected to immense pressure beyond carrying capacity. This has led to degradation of not only crop system but also the life-supporting system as a whole Mahapatra et al. (2012). Generally, Indian soils are poor in organic carbon due to tropical climate. Moreover, continuous imbalanced use of fertilizers also deteriorates the soil health. This situation warrants opting to organic nutrient management for sustaining productivity of cropping system. Ultimately, energy productivity is decreasing as a consequence of escalating of inputs cost without propor
Corresponding author Email: [email protected] 1Scientist, Central Potato Research Station, (ICAR) Shillong, Meghalaya, 793 009; 2Scientist; 6Senior Scientist, ICAR-RC-NEH-Sikkim Centre, Tadong, Gangtok, Sikkim 737102; 3Senior Scientist, NIASM, Baramati, Pune, Maharashtra 413 115; 4Scientist, Division of NRM, ICAR-RC-NEH Region, Tripura Centre; 5Former Professor and Dean Institute of Agricultural Sciences, BHU, Varanasi, Uttar Pradesh 221 005; 7Senior Research Fellow, Environmental Science, IARI, Pusa New Delhi 110 012
tionate improvement in output of particular crops. The organic sources of nutrient management offer most potential measures to minimize the dependency on non-renewable energy leading to increased share of renewable energy, which will pave the way for sustainability. Organic manure influence soil productivity through correction of deficiency of secondary and micro-nutrient and their effect on soil physical, chemical and biological properties. Biofertilizers, on the other hand are cost-effective and renewable source of plant nutrients to supplement the parts of chemical fertilizers. Keeping these points in view, an investigation was undertaken to study the effect of organic nitrogen sources and biofertilizers on production potential and energy budgeting of rice-based cropping sequence.
MATERIALS AND METHODS
A field experiment was conducted during 200506 and 200607 at Campus Research Farm, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi (25o18' N and 83o3' E and 129.93 m above mean sea-level). The soil was sandy clay loam with pH 7.4, moderately fertile, being low in organic carbon (0.45%), available nitrogen (185 kg/ha), and medium in available P (19.27 kg/ha) and K (208.4 kg/ha). The amount of total rainfall received during the period of investigation was 721.5 mm, major part of which was received in the month of August during experimentation. The maximum temperature of 44.1oC during the experimentation was recorded in June, whereas the lowest temperature remained at 7.4oC in December. The highest maximum relative humidity was 92% in July and the minimum relative humidity remained 14% in April. The average duration of bright sunshine day during the course of investigation was 7.5 hours. The range of maximum and minimum mean weekly bright sunshine duration was 9.5 to 1.9 hours during the period of investigation. The experiment on rice-based cropping systems with organic N nutrition treatments was laid out in split-plot design with 3 replications. Seven rice-based cropping sequences ricepotato (Solanum tuberosum L.)onion (Allium cepa L.); ricegreen pea (Pisum sativum var. hortense)onion; ricepotatocowpea (Vigna unguiculata subsp. sesquipedalis); ricegreen peacowpea; ricerajma (Phaseolus vulgaris L.)onion; ricerajmacowpea and ricemaize (Zea mays L.)cowpea were assigned to main plots and three treatments, viz. control (no application of any source of nutrients), recommended dose of nitrogen (RDN) through organic manure (1/3 farmyard manure + 1/ 3 vermicompost + 1/3 poultry manure) alone and RDN through organic manure [(1/3 FYM + 1/3 vermicompost + 1/ 3 poultry manure) along with biofertilizer (Azotobacter + phosphate-solubilizing bacteria)] were allocated to sub plots.
To avoid the mixing of manure and soil in different treatments, individual plots were thoroughly prepared by power tiller in each season. The farmyard manure, vermicompost and poultry manure contained viz. 0.50,
30 and 2.80% N; 0.09, 0.33 and 0.98% P and 0.42, 1.03 and 1.08% K respectively. Cultivation practices were followed as per standard recommendation for each crop. Variety HUBR 2-1 of rice, Kufri Badshah of potato, Early Apoorva of green pea, Pioneer Hybrid ( 3342) of maize, HUR 137 of rajma Agrifound Light Red of onion and Tokito Hybrid of cowpea were used in this experiment. Properly decomposed organic manures were applied 15 days before sowing the crops. The seed was inoculated with biofertilizers (Azotobacter + phosphatesolubilizing bacteria) and sown as per treatment. Rice grain equivalent yield and economics were calculated considering the prevailing market prices: rice grain (10,780/ t), potato (8,800/t), green pea (13,200/t), rajma (15,400/t), maize (6,600/t), onion (8,800/t) and cowpea (17,600/t). The system productivity was calculated by dividing the total rice-equivalent yield of the system by 365. Profitability in /ha/day was worked out by dividing the average net return over years by 365. The various practices involved in crop production and economic yield of component crops in the systems were converted into equivalent value of chemical energy (MJ/ha) for these conversions, standard values as given by Sriram et al. (1999) were used.
RESULTS AND DISCUSSION
Crops and system productivity
Productivity of rice did not differ significantly among different cropping systems; however, higher yield was observed in the system where legumes were included. Application of 100% recommended dose of nitrogen (RDN) through manure + biofertilizers recorded the highest productivity of rice (4.43t/ha) followed by organic manure alone (4.34 t/ha) (Table 1). Rice productivity was increased by 28% due to application of RDN through organic manure along with biofertilizers over control. Similarly, 100% RDN through organic manure alone enhanced the productivity of rice by 25.6% over the control. This might be owing to better availability of nutrients from organic manure. These results are in conformity with the findings of Gaur (2006). Further improvement in the yield of rice owing to combined use of organic manure along with biofertilizers might be because of sufficient release of N by mineralization at a desired rate, which resulted in better crop growth and improvement in various yield components of rice Babu et al. (2002); Chettri et al. (2002).
The maximum potato-equivalent yield (PEY) during winter season was recorded under system ricepotato cowpea, which was significantly more than other cropping systems except ricepotatoonion. It may be pointed out that potato equivalent yield of crops is a function of market price and the yield of particular crop. The potato gave higher economic yield and this accompanied with better market price resulted in higher PEY. Prasad et al. (2011) also observed higher productivity of ricepotatocowpea sequence over others. Among the manurial treatments, nitrogen application through organic manures alone or along with bio-fertilizers significantly improved PEY over the control. Enhancement in PEY was about 159% higher with application of nitrogen through organic manure along with biofertilizers compared with organic manure alone (126%) over the control. More than 33% increase in PEY of the winter season crop was recorded with biofertilizers. Increase in PEY might be owing to the continuous raising of organic potato bio-dynamically on the same site, which improved tuber production by enrichment of soil fertility.
The highest onion equivalent yield was recorded under ricegreen peaonion system, being significantly higher than that under all the other cropping systems and was followed by ricerajmaonion and ricepotatoonion systems, which were statistically at par and significantly superior to the other cropping systems. The onion itself gave higher economic yield with the inclusion of pea (a legume) as the preceding crop and this accompanied with better market value resulted in higher onion-equivalent yield compared with other cropping systems. Onion-equivalent yield of summer season crops was increased by about 219% with application of 100% RDN through organic manures along with biofertilizers, followed by 197% through organic manures without biofertilizers over the control. Therefore, about 21.9% improvement in productivity was recorded with the application of biofertilizers. Both the organic treatments along with biofertilizers or without biofertilizers brought about significant improvement in onion-equivalent yield over the control. This was owing to greater availability of nutrients in soil, improved soil physical condition and higher total uptake of nutrients because of better root penetration leading to better absorption of nutrients and moisture Meena et al. (2010).
The maximum rice grain equivalent yield was recorded under rice-potato-onion system, followed by ricepotato cowpea and ricerajmaonion systems, which remained statistically at par among themselves and significantly superior to others in this respect. Besides higher production potential of potato as well as onion and better market price were instrumental for attaining higher rice-grain equivalent yield by these systems Yadav et al. (2005). Application of nitrogen through organic manures along with biofertilizers brought about significant improvement in rice-grain equivalent yield (35.31 t/ha) over the remaining treatments. Rice-grain equivalent yield is directly associated with the yield of respective crops in the systems (Table 1) and so organic manure alone or along with biofertilizers enhanced the yield potential of crops which ultimately increased the rice-equivalent yield of the systems Debjani et al. (2009).
System efficiency indicators and net returns
Pooled data on system efficiency indicators as affected by different cropping systems revealed that ricepotato onion cropping system recorded significantly maximum production efficiency, land-use efficiency economic efficiency and net return over rest of the treatments (Table 2). However, next highest production efficiency, land-use efficiency, economic efficiency and net returns were observed under ricepotatocowpea cropping system. The maximum production, economic efficiency and net return were associated with higher production potential of potato and onion owing to the highest moisture content of their fresh produce (Singh and Bohra, 2009). The highest land-use efficiency was owing to higher duration occupied by the onion from nursery to maturity compared to the other crop in the system. Sharma et al. (2004) also observed higher production potential of potato accompanied with good monetary return from onion.
Among the organic treatment, application of 100% RDN through organic manures along with biofertilizers recorded significantly higher production efficiency, land-use efficiency, economic efficiency and net returns of the system, followed by 100 % RDN through organic manure alone over the control (Table 2). Consequently, increased in system indicator through application of organic ma-
Table 1. Effect of cropping sequence and organic treatment on equivalent yield (EY) of crops and system during rainy, winter and summer seasons
Treatment Rice grain yield Potato EY of rabi Onion EY of zaid Rice equivalent yield
(t/ha) crops (t/ha) crops (t/ha) of system (t/ha)
200607 200506 200607 200506 200607 200506 200607
Cropping sequence
Ricepotatoonion 3.98 3.92 19.47 19.77 18.94 19.30 35.34 35.81
Ricegreen peaonion 3.99 3.97 5.73 5.90 19.35 19.66 24.47 24.83
Ricepotatocowpea 4.07 4.01 20.32 20.58 13.81 14.20 31.93 32.40
Ricegreen peacowpea 4.08 4.03 5.20 5.35 13.30 13.70 19.18 19.59
Ricerajmaonion 4.16 4.14 11.94 12.26 19.17 19.49 29.56 30.06
Ricerajmacowpea 4.18 4.15 11.61 11.96 13.57 13.96 24.73 25.30
Ricemaizecowpea 4.21 4.16 10.25 10.60 13.82 14.19 23.85 24.39
SEm 0.12 0.11 0.63 0.62 0.41 0.41 0.47 0.51
CD (P=0.05) NS NS 1.94 1.92 1.26 1.26 1.43 1.57
Organic treatment
Control 3.47 3.44 6.25 6.27 6.75 6.82 14.09 14.13
% RDN through OM 4.37 4.32 13.99 14.30 19.90 20.36 32.02 32.62
% RDN through OM+ Biof. 4.45 4.40 15.98 16.46 21.34 21.89 34.91 35.71
SEm 0.05 0.05 0.28 0.27 0.20 0.22 0.29 0.28
CD (P=0.05) 0.16 0.15 0.82 0.79 0.57 0.64 0.84 0.80
nures, enhancing the nutrient availability in soil by improving their fertility status (might be favourable improvement in soil physical, chemical and biological properties) responsible for augmentation of crop productivity as well as efficiency of system. Similarly, enhancement in production efficiency, land-use efficiency, economic efficiency and net return were observed with the application of 100% RDN through organic manures along with biofertilizers over 100% RDN through organic manures (Table 2). This was mainly because of higher productivity through biofertilizers without proportionate increase in cost of cultivation.
Energy budgeting of system
In general, systems involving rice, winter crops or intensification by inclusion of summer crops resulted in higher energy input. Accordingly, the maximum energy input (61.08 103MJ/ha) was recorded under ricepotato onion systems. The other systems that recorded higher energy input in descending order were ricepotatocowpea, ricerajmaonion, ricemaizecowpea, ricegreen peaonion, ricerajmacowpea and ricegreen peacowpea systems. It is evident from the Table 2 that those systems having either potato or onion recorded higher energy because of intensive input on seed in potato and irrigation in onion attributed more energy compared to the other vegetable in winter and cowpea in summer respectively. Amongst various nitrogen substitutions, application of 100% RDN through organic manures along with biofertilizers recorded the maximum (56.89 103MJ/ha) pooled energy input, followed by same dose of nitrogen application through organic manure (55.30 103MJ/ha) alone over the control (34.99 103MJ/ha). Further, the data also revealed that energy consumption was higher through organic manure (100% RDN) with biofertilizers (62.59%), followed by without biofertilizers (58.05%) over the control treatment.
Pooled data pertaining to energy output and net energy return under different cropping systems revealed marked variation in energy output and net energy return of different cropping systems (Table 2). In general, energy output and net energy return of the system remained comparatively higher during the second year than that of the first year owing to improvement in system productivity during the second year because of the improvement in soil fertility. The maximum energy output (187.1103MJ/ha) and net energy return (126.00103MJ/ha) was recorded in ricepotatoonion system, and proved significantly superior to all the other systems except ricepotatocowpea
(177.8 103MJ/ha and 122.99103MJ/ha) and rice maizecowpea (165.0 103MJ/ha and 117.1 103MJ/ha) systems, which were statistically at par among them. The energy output and net energy return, however, are dependent on grain as well as straw yields under different cropping systems and higher yields associated to register greater output and net energy return. Nevertheless, the lowest energy (110.4 103MJ/ha) output and net energy return (71.0 103MJ/ha) was found through ricegreen peacowpea system during both the years. Application of recommended (100%) dose of nitrogen through organic manures along with biofertilizers recorded the maximum average energy output (180.2 103MJ/ha) and net energy
Table 2. Effect of different cropping sequence and organic treatment on system efficiency, net returns and energy budgeting (pooled data of 2 years).
Treatment Production Land use Economic Net returns Energy Energy Net energy Energy use
efficiency efficiency efficiency (103 /ha) input output returns efficiency
(kg/ha/day) (%) ( /ha/day) (103MJ/ha) (103MJ/ha) (103MJ/ha)
Cropping sequence
Ricepotatoonion 97.5 91.4 738 268.7 61.1 187.1 126.0 3.06
Ricegreen peaonion 67.5 85.8 502 182.2 45.6 123.8 78.2 2.66
Ricepotatocowpea 88.1 90.7 691 251.9 54.8 177.8 123.0 3.17
Ricegreen peacowpea 53.1 83.3 387 141.3 39.4 110.4 71.0 2.77
Ricerajmaonion 81.7 90.7 579 211.2 50.4 136.8 86.4 2.69
Ricerajmacowpea 68.5 89.5 507 185.2 44.2 124.4 80.2 2.80
Ricemaizecowpea 66.09 85.4 487 177.9 47.9 165.0 117.12 3.46
SEm 1.32 2.59 4 1.52 N A 7.20 7.02 0.15
CD (P=0.05) 4.09 7.98 13 4.69 N A 22.19 21.63 0.46
Organic treatment 0.00
Control 38.7 86.4 154 55.9 35.0 92.2 57.2 2.64
% RDN through OM 88.5 88.2 711 259.5 55.3 167.0 111.8 3.01
% RDN through OM + BF 96.7 89.8 803 292.4 56.9 180.2 123.3 3.15
SEm 0.77 0.40 2 1.04 N A 2.73 2.72 0.05
CD (P=0.05) 2.23 1.15 7 3.02 N A 7.91 7.89 0.15
Table 3. Effect of cropping system and organic treatment on fertility balance of soil
Treatment Soil organic Soil available Soil available Soil available
carbon (%) nitrogen (kg/ha) phosphorus (kg/ha) potassium (kg/ha)
A B C A B C A B C A B C
Cropping sequence
Ricepotatoonion 0.50 0.51 0.01 185.5 185.8 0.3 20.4 19.9 -0.4 210.3 205.1 -5.2
Ricegreen peaonion 0.50 0.52 0.02 185.5 193.3 7.8 20.4 21.7 1.4 210.3 218.4 8.1
Ricepotatocowpea 0.50 0.52 0.02 185.5 190.3 4.8 20.4 21.1 0.8 210.3 212.8 2.5
Ricegreen peacowpea 0.50 0.53 0.03 185.5 192.6 7.1 20.4 21.6 1.2 210.3 216.6 6.3
Ricerajmaonion 0.50 0.52 0.02 185.5 191.1 5.6 20.4 21.0 0.6 210.3 212.8 2.5
Ricerajmacowpea 0.50 0.53 0.03 185.5 192.8 7.3 20.4 22.0 1.7 210.3 220.5 10.2
Ricemaizecowpea 0.50 0.51 0.01 185.5 189.1 3.6 20.4 21.8 1.5 210.3 210.9 0.6
Organic treatment
Control 0.50 0.48 -0.02 185.5 177.2 -8.3 20.4 19.7 -0.7 210.3 201.4 -9.0
% RDN through OM 0.50 0.54 0.04 185.5 197.0 11.5 20.4 22.1 1.7 210.3 219.5 9.1
% RDN through OM + 0.50 0.54 0.04 185.5 197.9 12.4 20.4 22.2 1.8 210.3 220.8 10.5
Biofertilizer
A, Initial available nutrient; B, Final value of available nutrient after harvest of crop; C, Actual gain/loss (B-A)
return (123.3 103MJ/ha) followed by equal dose of nitrogen through organic manure (167.0 103MJ/ha and 111.8 103MJ/ha) alone. Both the manurial treatments were found significantly superior to the control.
In general, higher energy input resulted in lower energy-use efficiency while higher energy output is directly proportional to energy-use efficiency (ratio of energy output of total biomass and energy input). This result corroborates the findings of Billore et al. (1994). Analysis (Table 2) of the data revealed that among the various cropping systems, ricemaizecowpea systems recorded significantly highest energy-use efficiency than the other systems during both the years except ricepotatocowpea systems, which was statistically at par with each other. This was owing to higher stover yield of maize than that of other crops responsible for highest energy-use efficiency. However, among organic manure treatments, application of 100% recommended dose of nitrogen through organic manures along with biofertilizers recorded higher energy use efficiency about 4.65% and 19.32% over organic manure alone and control treatment, respectively, which was significantly superior to the control but at par with organic manure alone.
Soil fertility balance
Data pertaining to balance sheet of organic carbon and available NPK 2 years after experiment showed that all the cropping systems recorded marginal but positive increase in soil organic carbon, available N, P and K over the initial values except for a little negative balance for P and K under ricepotatoonion cropping system (Table 3). This was might be owing to nutrient mining from the same depth of soil because of shallow root system of potato and onion, as well as their high requirement of phosphorus and potassium. Similar results were reported by Yadav et al. (2013a).
Application of either organic manure alone or with biofertilizers improved the soil status with respect to soil organic carbon and available NPK. This increase may be attributed to higher microbial activity in the manurial treatments which favoured the conversion of the organically bound nitrogen to inorganic form Yadav et al. (2013b) also reported similar increase in available nutrients in soil owing to addition of organic manure and biofertilizers.
It was concluded that ricepotatoonion cropping system was found more productive, profitable and energy efficient than the other cropping system with application of 100% recommended dose of nitrogen through organic sources along with biofertilizers.
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