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1.
A 2-year field experiment was conducted to assess system productivity, nutrient use efficiency and apparent balances of phosphorus (P) and potassium (K) in diversified rice-based cropping systems at Gazipur, Bangladesh. Four cropping systems: wheat–fallow–rice, maize–fallow–rice, potato–fallow–rice and mustard–fallow–rice in main plots and four nutrient combinations: NPK, NK, NP and PK in sub-plots were arranged in a split-plot design with three replications. Receiving the NPK treatment, all the component crops gave the highest yield, and omission of N from fertilizer package gave the lowest yield. The maize–rice system removed the highest amount of N (217 kg ha?1), P (41 kg ha?1) and K (227 kg ha?1) followed by wheat–rice, potato–rice and the least in mustard–rice system. The wheat–rice and maize–rice system showed negative K balance of –35.5 and –60.4 kg ha?1 in NPK treatment, while potato–rice system showed a positive K balance of 31.0 kg ha–1 with NPK treatment. The N, P and K uptake and apparent recovery by the test crops may be used for site-specific nutrient management. The K rates for fertilizer recommendation in wheat and maize in Indo-Gangetic plain need to be revised to take account for the negative K balance in soil.  相似文献   

2.
In the present study, seven fertilizer treatments [T1, 50% NPK; T2, 100% NPK (Recommended dose of fertilizer, 200–65.4–124.5 kg N-P-K ha?1); T3, 150% NPK; T4, 100% PK; T5, 100% NK; T6, 100% NP and T7, control (zero NPK)] with four replications were assessed in the new alluvial soil zone (Entisols) of West Bengal, India. The objectives of the study were to generate information on potato productivity, profitability, indigenous nutrient supply and net gain/loss of NPK in post-harvest soil. Plants grown under higher NPK supply resulted in higher tuber yield and there were significant (p ≤ 0.05) reductions in total yield with nutrient omissions. Nutrient?limited yields were 19.78, 2.83 and 1.77 t ha?1 for N, P and K, considering total tuber yield (28.24 t ha?1) obtained under 100% NPK as targeted yield. Indigenous nutrient supply of N, P and K were estimated at 24.1, 22.34 and 110.22 kg ha?1, respectively that indicates higher K?supplying capacity of experimental soil as compared to N and P. Net income (US$1349 ha?1 year?1) and B:C ratio (1.91) was highest with 100% NPK, and further addition of NPK (150%) resulted in decrease on net return (US$1193 ha?1 year?1) and B:C ratio (1.73).  相似文献   

3.
Phospho-compost (PC) and poultry manure (PM) were evaluated in field experiments to diversify integrated nutrient management (INM) for rain-fed cotton. Seed cotton yield in the PC (2501–2579 kg ha?1) was similar to the recommended INM (2673 kg ha?1) treatment and was significantly better than nitrogen, phosphorus and potassium (100% NPK) (2130 kg ha?1) and farmers practice (FP) (1886 kg ha?1). Yield was lower in the PM (2476–2617 kg ha?1) than in the PC. Nutrient uptake was higher in all INM intervention plots due to an improvement in soil nutrient status compared with those receiving 100% NPK. Soil labile carbon values were higher in the INM treatments (333–452 mg kg?1), with a greater magnitude in the PC-amended plots (402–452 mg kg?1). Carbon management index (CMI) values were higher for the INM than treatments NPK and FP. Among INM interventions, PC plots had higher values than the PM.  相似文献   

4.
Abstract

The carbon (C) budget of managed grassland in a cool-temperate region of Japan was estimated using a combination of eddy covariance and the biometric method for five years, to evaluate the effect of manure application. Chemical fertilizer was applied to the fertilizer (F) plot at a rate of 79 ± 20 kg N ha?1 yr?1. In the manure (M) plot, dairy cattle manure was applied at a rate of 10 Mg fresh matter ha?1 yr?1 (1923 ± 407 kg C ha?1 yr?1, 159 ± 68 kg N ha?1 yr?1). There was no significant difference in seasonal gross primary production (GPP) and harvest between the treatment plots, indicating that both fertilizer and manure can increase the biomass production. Annual net ecosystem production (NEP) and ecosystem respiration (RE) was significantly different between the treatment plots. The difference in RE, and between M and F plots approximates heterotrophic respiration of manure (RHm), which ranged from 0.9 to 1.3 Mg C ha?1 yr?1. Average annual RHm was 1.1 ± 0.4 Mg C ha?1 yr?1, and accounted for 56% of the total amount of applied manure C. The annual net biome production (NBP) in the M plot (from 0.0 to 1.5 Mg C ha?1 yr?1) was significantly higher than in the F plot (?1.4 to 0.5 Mg C ha?1 yr?1). The long-term effect of manure application combined with chemical fertilizer did not reduce grass production compared with chemical fertilizer only; however, manure application decreased the NEP throughout manure decomposition, and long-term manure application enhanced the NBP.  相似文献   

5.
Cassava is an important subsidiary food in the tropics. In Tamil Nadu, India, microbial cultures were used to eradicate the tuberous root rot of cassava. Hence, an experiment was conducted for two consecutive years to test the effects of coinoculation of microbes on soil properties. The surface soil from the experimental site was analysed for soil available nutrients, soil enzyme activities and microbial biomass carbon. The treatment of Azospirillum with Trichoderma at the 50% recommended N:P2O5:K2O (NPK) rate (50:25:50 kg ha?1) significantly increased soil available nitrogen (142.81 kg ha?1) by 72.66% over uninoculated control. There was a significant increase in available phosphorus in soil by the inoculation of AM (arbuscular mycorrhizal) fungi with Trichoderma at the 50% recommended NPK rate (41.04 kg ha?1) compared to other treatments. The application of Pseudomonas fluorescens with Trichoderma at the 50% recommended NPK rate significantly increased available iron (19.34 µg g?1) in soil. The treatment of Azospirillum with Trichoderma increased urease enzyme activity at the recommended NPK rate (816.32 μg urea hydrolyzed g?1 soil h?1). Soil application of all cultures at the 50% recommended NPK rate significantly increased dehydrogenase activity (88.63 μg TPF g?1 soil) and β-glucosidase activity (48.82 μg PNP g?1 soil) in soil. Inoculation of Trichoderma alone at the 50% recommended NPK rate significantly increased microbial biomass carbon (3748.85 μg g?1 soil). Thus, the microbial inoculations significantly increased soil available nutrient contents, enzyme activities such as urease, dehydrogenase and β-glucosidase activity and microbial biomass carbon by reducing the amount of the required fertilizer.  相似文献   

6.
Excessive and inappropriate use of fertilizers is a key factor of low sugarcane yield and degradation of soil. A two-year (2013–14 and 2014–15) field study was conducted to assess the impact of combined application of organic and inorganic fertilizers on sugarcane at research farm of Shakarganj Sugar Research Institute, Jhang, Pakistan. Experiment was conducted under randomized complete block design with three replications. Treatments were used as control (no exogenous application), spent wash (160 t ha?1), (nitrogen, phosphorus and potassium) NPK (168:112:112 kg ha?1), spent wash (120 t ha?1) + NPK (42:28:28 kg ha?1), spent wash (80 t ha?1) + NPK (84:56:56 kg ha?1), spent wash (40 t ha?1) + NPK (126:84:84 kg ha?1), and spent wash (160 t ha?1) + NPK (42:28:28 kg ha?1). Application of spent wash @ 80 t ha?1 + NPK @ 84:56:56 kg ha?1 resulted maximum crop growth rate (11.35 g m?2 d?1), leaf area index (7.78), and net assimilation rate (2.53 g m?2 d?1). Maximum number of millable canes (14), weight per stripped cane (0.90 kg), stripped cane yield (117.60 t ha?1) and unstripped cane yield (141.25 t ha?1) were observed with spent wash @ 80 t ha?1 + NPK @ 84:56:56 kg ha?1, followed by sole fertilizer application @ 168:112:112 kg NPK ha?1 and spent wash @160 t ha?1 + NPK @ 42:28:28 kg ha?1. Similar trend was observed regarding quality parameters. The maximum benefit–cost ratio (1.80) was achieved with integrated application of spent wash @ 80 t ha?1 + NPK @ 84:56:56 kg ha?1.  相似文献   

7.
Abstract

To study the response of inorganic and organic nitrogen (N) sources both alone and in conjunction and their influence on soil quality, a field experiment was conducted during kharif and rabi seasons using sunflower (MSFH‐8) as test crop. The experimental site soil was Typic Haplustalf situated at Hayatnagar Research Farm of Central Research Institute of Dryland Agriculture, Hyderabad, India, at 17° 18′ N latitude, 78° 36′ E longitude. The experiment design was a simple randomized block design with 11 treatments replicated four times. Among all the treatments, vermicompost (VC)+Fert at 25+25 kg N ha?1 recorded the highest grain yields of 1878 and 2160 kg ha?1 during both kharif and rabi seasons, respectively, which were 43.9 and 85.1% higher than their respective control plots. Apparent N recovery varied from as little as 38.30% (FYM at 50 kg N ha?1) to 62.16 (25 kg N ha?1) during kharif and 49.65 (75 kg ha?1) to 83.28% (VC+Fert at 25+25 kg N ha?1) during rabi season. Conjunctive nutrient treatments proved quite superior to other set of treatments in improving the uptake of N, phosphorus (P), potassium (K), sulfur (S), and micronutrients in sunflower and their buildup in the soil. Highest relative soil quality indexes (RSQI) were observed under VC+Fert at 25+25 kg N ha?1 (1.00) followed by VC+Gly at 25+25 kg N ha?1 (0.87). Considering the yield and relative soil quality indices (RSQI), conjunctive applications of VC with either inorganic fertilizer, FYM, or Gly at 25+25 kg N ha?1 could be a successful and sustainable soil nutrient management practice in semi‐arid tropical Alfisols. Besides this, the fertilizer N demand could be reduced up to 50%.  相似文献   

8.
A field experiment was conducted on an Alfisol (kandic paleustalf) in Abeokuta, Southwestern Nigeria, for two seasons to assess the influence of inorganic and organic fertilizers on nitrogen (N), phosphorus (P), potassium (K), nutrient uptake and maize yield. The treatments consisted of three rates of organic fertilizer 0, 5 and 10 t ha?1 in the form of poultry manure and NPK fertilizer (20:10:10) applied at 0 and 120 kg ha?1. Maize (Zea mays) was used as the test crop. The results showed that the combined application of 10 t ha?1 poultry manure and 120 kg ha?1 NPK fertilizer enhanced the uptake of N, P and K better than other treatment combinations. Application of 10 t ha?1 poultry manure alone gave the highest grain yield, which was 67.02% higher than the control in the first season. Complementary application of 5 t ha?1 poultry manure with 120 kg ha?1 NPK 20–10-10 was recommended for grain yield.  相似文献   

9.
The growth and yield performance of green maize (Zea mays), followed by a late-season vegetable cowpea (Vigna unguiculata), was assessed with two rates of three different types of organic-based fertilizers (OBFs) fortified with an inorganic nutrient source. There was also an inorganic fertilizer treatment of NPK 20–10–10 applied at 300 kg ha?1 and a no-fertilizer control treatment. Maize growth was affected by fertilizer type and rate. Organic fertilizer, applied at 5 t ha?1, 3 weeks before maize released enough nutrients to have comparable growth as inorganic fertilizer. Applying the OBF at 2.5 t ha?1 was inadequate to give comparable growth. Application of fortified OBF with total nitrogen content higher than 2.4% N at 5.0 t ha?1 gave maize grain yields comparable with NPK fertilizer. Cowpea yields following early-season maize were highest with DPW + NPK. They were significantly lower with 2.5 t ha?1 of the OBFs. Application of the IAR&T-OBF (OBF made by Institute of Agricultural Research and Training) and decomposed poultry waste (DPW) + NPK at 5.0 t ha?1 gave comparable seed yields significantly higher than OYO-OBF (OBF made by Oyo State Government of Nigeria). NPK fertilizer application supported early-season maize cultivation, but it was not adequate to support the following cowpea. OBF should have nitrogen content up to 2.4% and applied at 5.0 t ha?1 to support an early-season maize cultivation with a late-season cowpea.  相似文献   

10.
Abstract

Effective soil diagnostic criteria for exchangeable potassium (Ex-K) combined with inorganic potassium (K) application rates were developed to lower K input in forage corn (Zea mays L.) production using experimental fields with different application rates and histories of cattle manure compost. Two corn varieties, ‘Cecilia’ as a low K uptake variety and ‘Yumechikara’ as a high K uptake variety, were selected from among 20 varieties and tested to make diagnostic criteria for K fertilization applicable to varieties with different K uptakes. The K uptakes increased from 96 to 303 kg K ha?1 for ‘Cecilia’ and from 123 to 411 kg K ha?1 for ‘Yumechikara’ with increasing Ex-K content on a dry soil basis from 0.11 to 0.92 g kg?1 with no inorganic K fertilizer application. The K uptake by corn for achieving the target dry matter yield of 18 Mg ha?1 was estimated to be approximately 200 kg K ha?1 in common between the two varieties. Yields of both varieties achieved the target yield at an Ex-K content of approximately 0.30 g kg?1 with no K fertilization, although ‘Yumechikara’ reached the target yield at a lower Ex-K content. At the low Ex-K content of 0.1 g kg?1, inorganic K fertilizer application at 83 kg K ha?1 was needed to gain the target yield, and apparent K recovery rate for K fertilizer was calculated to be 70% for both varieties. The K uptakes for gaining the target yield by the K fertilization were lower than that by soil K supply. Based on these results, diagnostic criteria of Ex-K and inorganic K application rates were set up as follows: at an Ex-K content of < 0.15 g kg?1, inorganic K fertilizer is applied at 83 kg K ha?1 (100 kg ha?1 as potassium oxide (K2O) equivalent); at an Ex-K content of 0.15–0.30 g kg?1, the application rate is reduced to 33 kg K ha?1 (40 kg K2O ha?1); at an Ex-K content of ≥ 0.30 g kg?1, inorganic K fertilizer is not applied because of sufficient K in the soil. Additionally, we propose that cattle manure compost be used to supplement soil K fertility.  相似文献   

11.
Soil-test crop-response experiments on rice were conducted in the Bastar Plateau Agroclimatic Zone of Chhattisgarh during 2009–2011 to assess yield, soil, plant, and fertilizer nitrogen (N), phosphorus (P), and potassium (K) nutrient relationships and calibrate optimum fertilizer doses for attaining yield targets. Soil fertility status was poor to medium for N (194–283 kg ha?1) and P (7.53–19.66 kg ha?1), and medium to good for K (226–320 kg ha?1). Based on nutrient requirements (NR, kg q?1) and contributions from soil (CS, %), fertilizer (CF, %), and farmyard manure (CFYM, %), optimum fertilizer doses were derived. The fertilizer doses were validated for attaining yield targets of 5000 and 6000 kg ha?1 in farmer’s fields. Rice yield within 10% deviation was attained, which indicated that soil-test-based fertilizer dose was superior. This approach could be adopted for regions with similar soil and agroclimatic conditions in other parts of the world to increase rice yields.  相似文献   

12.
Data from a 49-year-long organic–mineral fertilization field experiment with a potato–maize–maize–wheat–wheat crop rotation were used to analyse the impact of different fertilizer variations on yield ability, soil organic carbon content (SOC), N and C balances, as well as on some characteristic energy balance parameters. Among the treatments, the fertilization variant with 87 kg ha?1 year?1 N proved to be economically optimal (94% of the maximum). Approximately 40 years after initiation of the experiment, supposed steady-state SOC content has been reached, with a value of 0.81% in the upper soil layer of the unfertilized control plot. Farmyard manure (FYM) treatments resulted in 10% higher SOC content compared with equivalent NPK fertilizer doses. The best C balances were obtained with exclusive mineral fertilization variants (?3.8 and ?3.7 t ha?1 year?1, respectively). N uptake in the unfertilized control plot suggested an airborne N input of 48 kg ha?1 year?1. The optimum fertilizer variant (70 t ha?1 FYM-equivalent NPK) proved favourable with a view to energy. The energy gain by exclusive FYM treatments was lower than with sole NPK fertilization. Best energy intensity values were obtained with lower mineral fertilization and FYM variants. The order of energy conversion according to the different crops was maize, wheat and potato.  相似文献   

13.
Abstract

Field experiments were designed to quantify N2O emissions from corn fields after the application of different types of nitrogen fertilizers. Plots were established in South Kalimantan, Indonesia, and given either urea (200 kg ha?1), urea (170 kg ha?1) + dicyandiamide ([DCD] 20 kg ha?1) or controlled-release fertilizer LP-30 (214 kg ha?1) prior to the plantation of corn seeds (variety BISI 2). Each fertilizer treatment was equivalent to 90 kg N ha?1. Plots without chemical N fertilizer were also prepared as a control. The field was designed to have three replicates for each treatment with a randomized block design. Nitrous oxide fluxes were measured at 4, 8, 12, 21, 31, 41, 51, 72 and 92 days after fertilizer application (DAFA). Total N2O emission was the highest from the urea plots, followed by the LP-30 plots. The emissions from the urea + DCD plots did not differ from those from the control plots. The N2O emission from the urea + DCD plots was approximately one thirtieth of that from the urea treatment. However, fertilizer type had no effect on grain yield. Thus, the use of urea + DCD is considered to be the best mitigation option among the tested fertilizer applications for N2O emission from corn fields in Kalimantan, Indonesia.  相似文献   

14.
A long-term experiment was conducted at the Central Research Institute for Dryland Agriculture for 13 years to evaluate the effect of low tillage cum cheaper conjunctive nutrient management practices in terms of productivity, soil fertility, and nitrogen chemical pools of soil under sorghum–mung bean system in Alfisol soils. The results of the study clearly revealed that sorghum and mung bean grain yield as influenced by low tillage and conjunctive nutrient management practices varied from 764 to 1792 and 603 to 1008 kg ha?1 with an average yield of 1458 and 805 kg ha?1 over a period of 13 years, respectively. Of the tillage practices, conventional tillage (CT) maintained 11.0% higher yields (1534 kg ha?1) over the minimum tillage (MT) (1382 kg ha?1) practice. Among the conjunctive nutrient management treatments, the application of 2 t Gliricidia loppings + 20 kg nitrogen (N) through urea to sorghum crop recorded significantly highest grain yield of 1712 kg ha?1 followed by application of 4 t compost + 20 kg N through urea (1650 kg ha?1) as well as 40 kg N through urea alone (1594 kg ha?1). Similar to sorghum, in case of mung bean also, CT exhibited a significant influence on mung bean grain yields (888 kg ha?1) which was 6.7% higher compared to MT (832 kg ha?1). Among all the conjunctive nutrient management treatments, 2 t compost + 10 kg N through urea and 2 t compost + 1 t Gliricidia loppings performed significantly well and recorded similar mung bean grain yields of 960 kg ha?1 followed by 1 t Gliricidia loppings + 10 kg N through urea (930 kg ha?1). The soil nitrogen chemical fractions (SNCFs) were also found to be significantly influenced by tillage and conjunctive nutrient management treatments. Further, a significant correlation of SNCF with total soil nitrogen was observed. In the correlation study, it was also observed that N fraction dynamically played an important role in enhancing the availability pool of N in soil and significantly influenced the yield of sorghum grain and mung bean.  相似文献   

15.
A comprehensive long-term study (2006–2010) was undertaken to develop a balanced and integrated nutrient supply system for sunflower-based cropping sequence considering the efficient utilization of residual and cumulative soil nutrient balance along with added fertilizers by the crops grown in rotation. The fertilizer application was done in potato and sunflower while greengram was raised as such on their residual effect. Significant response in yield was observed with 150% of the recommended nitrogen, phosphorus and potassium (NPK) or inclusion of farmyard manure (FYM) with the recommended NPK in the cropping sequence indicating 6.2–7.0% gain in system productivity over the existing recommendations. Each additional unit of P and K nutrition prompted system productivity by 18.9 and 11.0 kg kg?1 of applied nutrient, respectively. Apparent yield decline was observed in K and PK omission plots to the extent of 15.8 and 27.4% in potato, 10.5 and 23.9% in sunflower and 4.2 and 8.3% in greengram, respectively, compared to the recommended fertilization. The superiority of the FYM along with the recommended NPK (potato/sunflower) was evident on the overall profitability and sustainability of the system, highlighted by the significantly higher productivity (7.16 t SFEY ha?1), sustainability yield index (SYI; 0.76), production efficiency (PE; 27.85 kg SFEY ha?1 day?1) and net returns (2520 USD ha?1) with a B:C ratio of 2.91. Apparent change in potassium permanganate (KMnO4)-N was negative in all the treatments while N and P balance was positive with 150% NPK fertilization. Nutrient uptake exceeded the replenishment with 100% NPK application and maintained net negative soil nutrient stock for all the primary nutrients, indicating the need for revalidation of the existing recommendations in the system perspective. Conspicuous improvement in residual soil fertility in terms of maximum buildup of soil organic carbon (14%) and enhancement in soil KMnO4-N (4.2%), Olsen-P (19.4%), ammonium acetate (NH4OAc)-K (5.8%) and dehydrogenase enzyme activity (44.4%) was observed in FYM-treated plots over the initial values. The study suggested that the inclusion of legumes and FYM application with the recommended NPK in potato-sunflower cropping sequence will sustain the system’s productivity through the efficient use of nutrients, enhanced microbial activity and improved soil health while combating escalating prices of fertilizers as well as environmental issues in the Indo-Gangetic plains of India and similar environments.  相似文献   

16.
Field experiments were conducted on cotton to evaluate the different cotton-based intercropping system along with balanced nutrient management practices on enhancing cotton productivity. Cropping systems have been considered as main plots and nutrient management practices have been considered as subplots. The results showed that cotton + onion system recorded the highest cotton equivalent yield (CEY) of 2052 and 1895 kg ha?1 which was on par with cotton intercropped with dhaincha, which recorded 2010 and 1894 kg of CEY ha?1 in both the seasons. Combined application of 100% recommended NPK with bioinoculants (S5) registered highest CEY in both the seasons. Cotton intercropped with dhaincha (M2) recorded highest uptake of N, P, and K. Among the nutrient management practices, application of 100% recommended NPK with bioinoculants (S5) showed highest uptake of N, P, and K. A similar trend was noticed in the post-harvest soil fertility too and it is significantly higher under cotton + dhaincha and application of 100% recommended NPK with bioinoculants treatment compared to 100% recommend NPK alone. It could be concluded from these results that crop productivity can be improved and soil fertility status can be sustained with integrated plant nutrient management practices.  相似文献   

17.
Abstract

Nitrogen (N) and potassium (K) fertility management of maize (Zea mays L.) in the humid subtropical Mississippi Delta may differ from a temperate climate because of its use in rotation with cotton (Gossypium hirsutum L.), soil temperatures rarely falling to 0°C, and heavy winter rains that facilitate nutrient losses. An experiment to determine the [N] (concentration=[ ]), phosphorus [P], [K], calcium [Ca], magnesium [Mg], iron [Fe], manganese [Mn], zinc [Zn], and copper [Cu] and their total contents plant?1 of maize grown in rotation with cotton, using N fertility levels of (134, 179, 224, 269, and 314 kg N ha?1) in combination with K fertility levels of (0, 45, 90, and 134 kg K ha?1) was conducted in 2000 and 2001 at Tribbett, MS. Ear leaves, immature ears, and husks collected at growth stage R2 and grain and stover collected 21 days after R6 were dried, weighed, and analyzed for nutrient concentration. Plots were also harvested for yield, kernel weight, grain bulk density, and harvest index (HI). Increased [N] values of about 1.3 mg g?1 occurred in all organs except the stover between 134 and 314 kg N ha?1 N fertility. Stover [N] increased approximately 3.0 mg g?1 within the same N fertility range. Total N content of ear leaves, grain, and stover increased by about 11.0, 550.0, and 730.0 mg plant?1, respectively, with N fertility increased from 134 to 314 kg N ha?1. Yields, kernel weights, grain bulk densities, and harvest indices also increased with added N fertility. Several micronutrient concentrations and contents increased as N fertility increased. Increased K fertility had only limited influence on concentrations of most nutrient elements. The nutrient contents of most elements in the stover increased with added K fertility compared with plots that received no supplemental K fertilizer. These data showed between 139 and 265 kg N ha?1 was permanently removed by grain harvest and suggest that N fertility recommendations for the Mississippi Delta may be low for maize yield goals above 10 Mg ha?1. Added K fertilizer has minimal benefit to maize when soil test levels are adequate but are important to succeeding cotton crops where K uptake during fruiting can exceed the soil's ability to release K for uptake.  相似文献   

18.
A field study conducted for three crop years (June?–?July) from 1995?–?96 to 1997?–?98 at the Indian Agricultural Research Institute, New Delhi involving five rice-based cropping systems and six nutrient combinations indicated that rice?–?wheat?–?mungbean (RWM), rice?–?potato?–?mungbean (RPM), rice?–?rapeseed?–?mungbean (RRsM) and rice?–?clover (RC) cropping systems gave 0.7?–?1.0, 3.2?–?5.9, 0.2?–?2.2 and 1.5?–?3.6 t ha?1 yr?1, respectively, higher productivity and removed 7.9?–?22.6, 38.0?–?64.5, 53.0?–?61.8 and 51.4?–?66.1?kg ha?1 yr?1, respectively, more nitrogen, 2.3?–?7.1, 14.5?–?22.8, 3.8?–?7.2 and 17.3?–?21.7?kg ha?1 yr?1, respectively, more phosphorus and 1.6?–?11.4, 15.3?–?42.3, 8.2?–?22.7 and 40.8?–?57.8?kg ha?1 yr?1, respectively, more potassium than the rice?–?wheat (RW) cropping system which led to a net balance of +?151, +?58, ??153 and ??167?kg ha?1 of nitrogen, +?13, ??27, ??8 and ??59?kg ha?1 of phosphorus and ??549, ??551, ??558 and ??691?kg ha?1 of potassium after three cycles of RWM, RPM, RRsM and RC cropping systems, respectively against a net balance of +?201, +?26 and ??533?kg ha?1 of N, P and K, respectively in the RW cropping system. Application of FYM along with NPK in these cropping systems changed the negative balance of nitrogen and phosphorus into positive balance and reduced the negative balance of potassium by 151?–?378?kg ha?1. Application of P and K fertilizers along with nitrogen also helped in arresting the negative balance of P and K under different rice based cropping systems. These results thus indicate that balanced use of NPK and FYM plays a major role for sustaining the productivity of a cropping system.  相似文献   

19.
Long-term effects of chemical fertilizers and farmyard manure (FYM) in rice (Oryza sativa)–wheat (Triticum aestivum) cropping system were monitored for two consecutive years after 38 and 39 years on productivity and soil biological properties of Mollisols. The study encompasses varying chemical fertilizer levels of optimum fertilizer rate (120, 26 and 37 kg ha?1 N, P and K, respectively) for both the crops. The treatments were application of 50% NPK, 100% NPK, 150% NPK, 100% NPK + hand weeding (HW), 100% NPK + Zn, 100% NP, 100% N, 100% NPK + 15 t FYM ha?1, 100% NPK(-S) and unfertilized control. The rice and wheat yields were highest with 100% NPK + 15 t FYM ha?1. This treatment also gave maximum and significantly more counts of bacteria, fungi and actinomycetes in soil than all the other treatments after crop harvest. The soil microbial biomass C (410.0 and 407.5 µg g?1) and N (44.53 and 48.30 µg g?1) after rice and wheat, respectively, were highest with 100% NPK + 15 t FYM ha?1, which were significantly higher over all the other treatments. The activities of soil enzymes like dehydrogenase, acid and alkaline phosphatase, arylsulphatase and urease and CO2 evolution rate with 100% NPK + 15 t FYM ha?1 were also found significantly higher over the other treatments. Fertilizer treatments with 100% NPK and 150% NPK were comparable and significantly better than application of 50% NPK, 100% N, 100% NP and 100% NPK(-S) in various studied soil biological properties. Integrated use of 100% NPK with FYM sustained the higher yields and soil biological properties under rice–wheat cropping system in Mollisols. Application of Zn and hand weeding with 100% NPK were found better over 100% NPK alone in rice and wheat productivity. Imbalanced use of chemical fertilizers had the harmful effect on soil biological health.  相似文献   

20.
Experiments were conducted to test the superiority of treatment combinations of nitrogen (N; 0, 50, 100, 150, 200 kg ha?1), phosphorus (0, 30, 60, 90 kg ha?1) and potassium (0, 30, 60 kg ha?1) for finger millet during 2005–2007. Application of 200-90-60 kg ha?1 gave maximum yield of 1666, 1426 and 1640 kg ha?1 in 3 years, respectively. The yield regression model through soil and fertilizer nutrients gave predictability of 0.98, 0.97 and 0.98, with sustainability yield index (SYI) of 50.4, 49.4 and 52.5 in 2005, 2006 and 2007, respectively. Optimum nitrogen, phosphorus and potassium (NPK) doses for attaining yields of 800 and 1200 kg ha?1 were derived at soil nitrogen, phosphorus and potassium of 75–400, 10–70 and 150–750 kg ha?1. Fertilizer nitrogen, phosphorus and potassium ranged from 30–128, 3–19, 13–25 kg ha?1 and 105–203, 4–32, 27–39 kg ha?1 for attaining 800 and 1200 kg ha?1 yield, respectively. The doses could be adopted for attaining sustainable yields under semiarid Alfisols.  相似文献   

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