Effect of a four-decade long application of fertilizers,farmyard manure and lime,on forms of soil acidity and their relationship with yield of wheat and maize in an acid Alfisol

The present investigation was undertaken in the on-going long-term fertilizer experiment initiated during 1972 at experimental farm of Department of Soil Science, Himachal Pradesh Agricultural University, Palampur, India. Continuous application of fertilizers either alone or in combination with farmyard manure (FYM)/lime affected different forms of soil acidity (total acidity, total potential acidity, pH dependent acidity, extractable acidity, exchangeable acidity, and non-exchangeable acidity) significantly, in surface and sub-surface layers. Continuous cropping with the application of lime and optimal doses of fertilizers decreased different forms of soil acidity at all the depths, significantly. Highest productivity of wheat and maize was recorded in 100% (nitrogen, phosphorus, potassium) NPK + FYM, which was at par with 100% NPK + lime. Different forms of soil acidity were found to be negatively correlated with wheat and maize yield. Grain and straw/stover yield of wheat and maize showed the highest negative correlation values with non-exchangeable acidity.     

Effect of 46 years' application of fertilizers,FYM and lime on physical,chemical and biological properties of soil under maize–wheat system in an acid Alfisol of northwest Himalayas

Imbalanced fertilizer use with intensive cropping has threatened the sustainability of agroecosystems, especially on acid soils. An understanding of the long-term effects of fertilizers and amendments on soil health is essential for sustaining high crop yields. The effects of application of fertilizers, and amendments for 46 years on soil properties and maize yield in an acid Alfisol were investigated in this study. Ten fertilizer treatments comprising different amounts of NPK fertilizers, farmyard manure (FYM) and lime, and one control, were replicated three times in a randomized block design. At 0–15 cm soil depth, bulk density was least (1.20 t/m³), porosity (49.8%) and water holding capacity (61.7%) were greatest in 100% NPK + FYM, corresponding to the largest organic carbon content (13.93 g/kg). Microbial biomass C and dehydrogenase activity in 100% NPK + FYM were 42% and 13.7% greater than 100% NPK, respectively. Available nutrients were significantly more with 100% NPK + FYM and 100% NPK + lime than control and other fertilizer treatments. At 15–30 cm depth, the effect of various treatments was comparable to the surface layer. Grain yield declined by 55% and 53% in 100% NPK(-S) and 100% NP, respectively, compared with 100% NPK, whereas 100% N as urea alone eventually led to crop failure. Soil porosity recorded the greatest positive correlation (r = .933**), whereas bulk density recorded a negative significant correlation (r = −.942**) with grain yield. The results suggest that integrated use of FYM/lime with chemical fertilizers is a sustainable practice in terms of crop yield and soil health, whereas continuous application of urea alone is detrimental to the soil health.     

Long-Term Effect of Fertilizers and Amendments on Depth-Wise Distribution of Available NPK,Micronutrient Cations,Productivity, and NPK Uptake by Maize-Wheat System in an Acid Alfisol of NorthWestern Himalayas

The present study was undertaken in the ongoing long-term fertilizer experiment initiated during 1972 at experimental farm of Department of Soil Science, Himachal Pradesh Agricultural University, Palampur (India). Soil samples collected from three depths (0–0.15, 0.15–0.30, and 0.30–0.45 m) were analyzed for pH; organic carbon; CEC; available N, P, and K; and micronutrients cations. Continuous use of optimal dose of fertilizers and FYM-influenced pH, organic carbon, CEC, available NPK, and DTPA extractable micronutrient cations significantly. The contents of organic carbon, available N, P, K, Fe, Mn, Zn, and Cu were higher in top soil layer (0–0.15 m) compared to lower depths (0.15–0.30 and 0.30–0.45 m). Highest productivity of wheat (89.89 q ha^?1) and maize (156.52 q ha^?1) was recorded under 100% NPK + FYM, which was at par with 100% NPK + lime. Application of 100% NPK along with amendments (FYM/lime) recorded significantly higher NPK uptake over other treatments.     

Effect of Mycorrhiza,Organic Sources,Lime, Secondary and Micro-nutrients on Soil Microbial Activities and Yield Performance of Yam Bean (Pachyrhizus erosus L.) in Alfisols

Effect of integrated use of mycorrhiza, lime, inorganic fertilizers, and organic manures on microbial activities and yield performance of yam bean (Pachyrhizus erosus L.) was studied for two consecutive kharif (rainy) seasons during 2013–14 and 2014–15 in an acid Alfisol. The experiment was laid out with 16 treatments consisting of graded doses of soil test–based nitrogen, phosphors, and potassium (NPK); lime; mycorrhiza; organic sources, that is, farmyard manure (FYM), vermicompost, and green manure; secondary magnesium sulfate (MgSO₄) and micronutrients zinc sulfate (ZnSO₄ and borax). Significantly highest mean tuber yield (29.61 t ha^?1) was recorded due to integrated application of lime + FYM + NPK + ZnSO₄. Graded doses of NPK showed a mean yield response of 65%, 134%, and 191% due to addition of 50%, 100%, and 150% of NPK over control, respectively. Inoculation of vesicular–arbuscular mycorrhiza (VAM) combined with NPK and FYM recorded a mean tuber yield of 25.14 t ha^?1. Highest mean dry matter (18.85%) was recorded due to application of 150% NPK, whereas highest starch content on fresh weight basis was recorded due to integrated use of lime + FYM + NPK + MgSO₄ (11.11%). Application of 150% NPK has recorded highest dehydrogenase activity (2.018 µg TPF h^?1 g^?1) and fluorescein diacetate hydrolysis assay (2.012 µg g^?1 h^?1). Fungal inoculation of VAM in combination with lime + FYM + NPK recorded highest acid and alkaline phosphatase activities (82.20 and 67.02 µg PNP g^?1 soil h^?1, respectively). Soil biological activities and phosphatase activities had highly significant relationship with tuber yield and biochemical constituents of yam bean. The study emphasized the conjunctive use of soil test–based inorganic fertilizers, lime, and organic manures to enhance the enzymatic activities and to realize higher crop yields of yam bean in acid Alfisols.     

Vertical Distribution of Sulfur Fractions in a Continuously Fertilized Acid Alfisol Under Maize​–Wheat Cropping System

Vertical distribution of sulfur fractions was studied in a long-term fertilizer experiment at the experimental farm of Department of Soil Science, Himachal Pradesh Agricultural University, Palampur (India), comprising various combinations of fertilizer and amendments. Initially, available nitrogen (N) was high, and phosphorus (P), potassium (K), organic carbon were optimum. Different forms, viz., available, water-soluble, heat-soluble, organic, and total sulfur were significantly affected by continuous cropping and decreased with depth. However at surface layer, 100% NPK(-S) resulted in 67%, 70%, 34%, 47%, and 48% reduction in these fractions, respectively, as compared to 100% NPK. Among all, organic sulfur was recorded highest. Hundred percent NPK + farmyard manure (at par with 100% NPK + lime) recorded highest maize and wheat yield. Hundred percent NPK(-S) recorded 39% and 44% reduction in grain yield of maize and wheat as compared to 100% NPK, respectively. Sulfur fractions were positively and significantly correlated with yield of maize?–wheat which shows the importance of sulfur fertilization.     

Effects of 41 Years of Application of Inorganic Fertilizers and Farm Yard Manure on Crop Yields,Soil Quality,and Sustainable Yield Index under a Rice-Wheat Cropping System on Mollisols of North India

The present investigation was carried out to evaluate the effect of integrated nutrient management (INM) on crop yield sustainability and soil quality in a long-term trial initiated during the wet season of 1971 under a humid subtropical climate. Over 41 years of study, 100% nitrogen, phosphorus, and potassium (NPK) + farm yard manure (FYM) at 15 t ha^?1 recorded the most sustainable grain yields. Optimal and superoptimal NPK fertilizers gave quite similar crop yields to that of 100% NPK + FYM at 15 t ha^–1 up to two decades but thereafter yields declined sharply due to emergence of zinc (Zn) deficiency. The sustainable yield index (SYI) values indicated that wheat yields were more sustainable than rice. Soil organic carbon and available N, P, K, and Zn in the control plot decreased the most, whereas 100% NPK + FYM at 15 t ha^–1 improved available N, P and K, maintained soil organic carbon, and decreased Zn over initial levels. Grain yield and SYI were more significantly correlated with Soil Organic Carbon (SOC). Continuous application of FYM contributed the maximum Soil Quality Index (SQI) (0.94), followed by Zn.     

Effect of Effective Microorganism Application on Crop Growth,Yield, and Nutrition in Vigna radiata (L.) Wilczek in Different Soil Amendment Systems

A pot experiment was conducted in heat-sterilized soil to evaluate the effect of effective microorganism (EM) application on growth, yield, and nutrient uptake in Vigna radiata (L.) Wilczek var. NIAB Mung 98 in different soil amendment systems. Pot soil was amended with farmyard manure (FYM), Trifolium alexanrinum L. crop residues (TCR), and half (½NPK) and recommended dose (NPK) of chemical fertilizers. The EM application significantly enhanced shoot and root biomass in TCR-amended soil. However, grain yield was significantly enhanced in FYM, TCR, and NPK amendments by 24%, 15%, and 84%, respectively, as a result of EM application. Effect of EM application on nutrient uptake was variable with respect to soil amendment and plant growth stage. In general, EM application enhanced plant nitrogen (N), phosphorus (P), and potassium (K) nutrition in organic amendments while its effect was either negative or insignificant in chemical fertilizer amendments. Effects of EM application on plant nutrient uptake were more pronounced at maturity than at flowering stage.     

Relative effect of organic and conventional farming on growth,yield and grain quality of scented rice and soil fertility 1 : Relative wirkung von organischem und konventionellem ackerbau auf wachstum,ertrag und kornqualität von reis und auf die bodenqualität

A field experiment was conducted during the kharif season of the crop year 2001 at the Indian Agricultural Research Institute, New Delhi, to study the comparative effects of organic and conventional farming on scented rice. Grain yield of rice increased significantly with increasing rate of fertilizer application only up to 60?kg N?+?13?kg P?+?17?kg K ha^???1. The effect of 10 t ha^???1 farmyard manure (FYM) was found to be similar to 60?kg N?+?13?kg P?+?17?kg K ha^???1, whereas the effect of Sesbania green manuring (SGM) was similar to 120?kg N?+?26?kg P?+?34?kg K ha^???1. Inoculation of BGA (Blue green algae) with FYM or SGM had no additional advantage over FYM or SGM alone. The highest yield (5.2 t/ha) of rice was obtained when FYM?+?SGM?+?BGA?+?PSB (Pseudomonas striata) were applied together. The yield obtained with this combination was significantly more than that obtained with 180?kg N?+?39?kg P?+?51?kg K ha^???1. A similar trend was observed in N, P, and K uptake of rice. Inorganic nutrients had no significant effect on grain quality parameters like head rice recovery (HRR), kernel length (KL), kernel breadth (KB) and KL?:?KB ratio, whereas organic manures and biofertilizers resulted in an increase in HRR, KL and KL?:?KB ratio. A combination of FYM?+?SGM?+?BGA?+?PSB also resulted in highest organic C and available N content in soil and thus holds a promise for sustainable production.     

Effect of organic and inorganic sources of nutrients on yield,economics, and energetics of pepper and soil properties in naturally ventilated polyhouse

A field experiment was conducted during the summer season of 2009 and 2010 at Vivekananda Parvatiya Krishi Anusandhan Sansthan, Hawalbagh, Almora, Uttarakhand, under the mid-hills of north-western Himalaya, to study the effect of farmyard manure and fertilizers on fruit yield, economics, energetics of pepper (Capsicum annuum L.) and on soil chemical properties. The highest level of farmyard manure (20 t ha^?1) along with 125% of recommended NPK (125, 27.5, and 52.1 kg N, P and K ha^?1) resulted in significantly higher fruit yield (33.9 t ha^?1) over other combinations. Both farmyard manure and inorganic fertilizers significantly increased fruits/plant, average fruit weight, plant height, fruit length, and fruit diameter. The maximum net returns (4520 $ ha^?1) was achieved at 20 t of FYM along with 125% of recommended NPK. Energy ratio of 1.29 and 1.13 was the highest under 20 t FYM ha^?1 and 125% of recommended NPK, respectively. Available nutrients (N, P, and K) improved the status of the soil significantly due to 20 t ha^?1 of FYM and 125% of recommended NPK over other treatments.     

Co-application of sugarcane bagasse biochar,farmyard manure and mineral nitrogen improved growth indices of corn grown in alkaline calcareous soil

Abstract

Soil quality and crop productivity can be improved by the combined soil application of organic amendments and synthetic fertilizers. We evaluated the sole and combined effects of sugarcane-bagasse biochar (SBB), farmyard manure (FYM) and nitrogen (N) fertilizer on soil properties and corn yield traits. Three N fertilizer rates (0, 50 and 100% of recommended) were used with or without the organic amendments. We observed significant increases in soil nitrate-N (at vegetative and reproductive phases), ammonical-N and microbial-biomass-N contents in responses to a co-application of 0.5% SBB, 0.5% FYM and 100% N fertilizer (p?≤?0.05). While the same co-application also resulted in the most significant soil organic carbon value, the maximum soil microbial biomass carbon was observed when 0.5% SBB and 0.5% FYM combination was applied along with 50% N fertilizer (p?≤?0.05). Plant growth indices—shoot length and, fresh and dry weights of shoot and root were also recorded to be the highest where the same organic amendments were applied in addition to a 50% or 100% mineral N fertilizer (p?≤?0.05). Combined application of the organic amendments effectively improved soil CEC compared to those in responses to individual applications of SBB and FYM (p?≤?0.05). Conclusively, for increasing the corn yield and improving the soil quality, the co-application of 0.5% SBB and 0.5% FYM was more effective than any of the individual 1% applications; Additions of 50% and 100% mineral N to the organic combination were equally useful for increasing the grain yield.     

Depth dynamics of soil N contents and natural abundances of 15N after 43 years of long-term fertilization and liming in sub-tropical Alfisol

The aim of this study was to understand impacts of long-term (43 years) fertilization on soil aggregation, N accumulation rates and δ¹⁵N in surface and deep layers in an Alfisol. Soil samples from seven treatments were analysed for N stocks, aggregate-associated N in 0–30 cm and the changes in δ¹⁵N in 0–90 cm depths. The treatments were: unfertilized control (control); recommended N dose (N); recommended N and phosphorus doses (NP); recommended N, P and potassium doses (NPK); 150% of recommended N, P and K doses (150% NPK); NPK + 10 Mg FYM ha^?1 (NPK + FYM) and NPK + 0.4 Mg lime ha^?1 (NPK + L). Results revealed that plots under NPK + FYM had ~39% higher total N concentrations than NPK + L in 0–30 cm soil layers. In NPK + L, macro-aggregates had 35 and 11% and microaggregates had 20 and 9% lower δ¹⁵N values than NPK + FYM in 0–15 and 15–30 cm soil layers, respectively. However, plots receiving NPK + FYM had ~39% greater deep soil (30–90 cm) N accumulation than NPK + L. These results would help understanding N supplying capacity by long-term fertilization and assist devising N management strategies in sub-tropical acidic Alfisols.     

Soil Quality for Rice Productivity and Yield Sustainability under Long-term Fertilizer and Manure Application

Productivity and sustainability of rice-rice cropping system depend upon the soil quality which is primarily governed by application of fertilizers and manures. However, such information is limited and hence, the present investigation was carried out in a 9-year-old long-term fertilizer experiment at Bhubaneswar, India. There were seven treatments (control, application of 100% NPK, 150% NPK, 100% NPK + Zn, 100% NPK + FYM, 100% NPK + Zn + B, and 100% NPK + Zn + S) laid out in randomized block design with four replications. Indicators of soil quality (physical, chemical, and biological) were diagnosed from 30 numbers of soil properties measured on the post-wet season soil and soil quality was assessed taking productivity and sustainability of dry season rice as goal functions. Results revealed that the highest productivity and sustainability of dry season rice was found with application of 100% NPK + FYM. This treatment, in general, showed better physical, chemical, and biological properties than rest of the treatments. The highest soil quality index (SQI) was recorded in 100% NPK + FYM (0.941) treatment followed by 150% NPK (0.826) with CEC diagnosed as the only key indicator for rice productivity. For yield sustainability in dry season, reserve K and total N were important contributing 89% and 11%, respectively to the SQI. Therefore, these soil properties could be used to monitor soil quality in wet season. Application of FYM along with 100% NPK could sustain the productivity of dry season rice by improving soil properties under subtropical rice-rice system.     

Effect of nutrient‐management practices on growth,fruiting pattern,and yield of Asiatic cotton (Gossypium arboreum L.)

Asiatic cotton (Gossypium arboreum) is mostly grown in the rainfed regions of India. However, little is known about the effects of nutrient‐management practices on plant growth and fruiting pattern of Asiatic cotton. Therefore, plant growth and fruiting pattern under four nutrient‐management treatments, N, NPK, FYM (10 Mg ha^–1), and INM (integrated nutrient management: a combination of NPK and FYM) were quantified during 2000–01 to 2002–03 (years 16 to 18 of a long‐term field experiment). Plants of the INM and FYM treatments were taller (68.4–149.5 cm) and had more main stem nodes per plant (30.5–44.5) as compared to N and NPK treatments. In treatment N, the shortest plants (50.9–83.6 cm) and the least number of fruiting structures were produced. Plants of the INM and FYM treatments accumulated more squares and bolls. Maximum boll production was 10–19 days earlier with the manure‐amended than the N and NPK treatments. Treatment N had the lowest seed cotton yield (639–790 kg ha^–1), because of small boll size (1.48–1.73 g) and few open bolls. Seed cotton yield followed the trend: NPK (815–1278 kg ha^–1) < INM (776–1551 kg ha^–1) < FYM (902–1593 kg ha^–1). Water stress and nutrient deficiencies (P and Zn in the N and Zn in the NPK treatments) as a consequence of nutrient depletion over the years may have decreased seed cotton yields in treatments that received mineral fertilizer alone in comparison with manure‐amended treatments. On a long‐term basis, FYM application should therefore form an integral part of nutrient recommendation.     

Dynamics of zinc under long-term application of chemical fertilizers and amendments by maize–wheat cropping sequence in Typic Hapludalfs

This present investigation took place on a continuing long-term fertilizer experiment, initiated in 1972 at the experimental farm of the College of Agriculture CSK HPKV, Palampur, aimed at studying nutrient dynamics of micronutrients, especially Zn, after continuous use of chemical fertilizers and amendments over the previous 36 years in an acid Alfisol under a maize–wheat system. Treatments investigated were as follows: T₁: Control; 100% N; 100% NP; 100% NPK (optimal application - 120:26:33(maize)/25(wheat)); 100% NPK + FYM (10 t ha⁻¹ to the maize crop); T₆: 100% NPK + lime (900 kg ha⁻¹); T₇: 100% NPK + Zn (25 kg ha⁻¹ as ZnSO₄); T₈: 100% NPK + Hand weeding; T₉: 100% NPK (-S); T₁₀: 150% NPK (super-optimal application); and T₁₁: 50% NPK (sub-optimal application). Different forms of zinc in soil were determined through a sequential extraction method. Results revealed that previous applications of high-analysis fertilizers and amendments caused a marked depletion in the pools of Zn as compared to buffer plots. All pools of Zn as well as crop productivity and Zn uptake were noticeably greater in farmyard manure (FYM)-amended plots compared with plots not receiving fertilizer. The residual fraction was the dominant form but organically bound and exchangeable forms were found to play major role in nutrient supply, crop productivity and nutrient uptake. Correlation and regression analysis studies showed that organic forms constituted the most important pool contributing towards variation in yield and uptake by maize and wheat crops. Exchangeable and organically bound forms contributed significantly towards the availability of DTPA-extractable Zn in soil.     

Potential of sawdust and corn cobs derived biochar to improve soil aggregate stability,water retention,and crop yield of degraded sandy loam soil

Abstract

Poor soil structure is the main cause of soil degradation; however, biochar the solid carbon-rich production of pyrolysis biomass could improve the soil structure. Biochar from the feed stock sawdust (SD) and corn cobs (CC) was pyrolyzed at 450?°C. Wheat was grown as a test crop and treatments were control, NPK, SDB1% (sawdust biochar), CCB1% (corn cobs biochar), SDB0.5%+CCB0.5%, SDB1%?+?½ NPK, CCB1%?+?½ NPK. The higher growth, higher grain and dry matter yield were displayed by biochar?+?NPK. The lowest pH, the higher organic matter, available P and available K were observed in SDB0.5%+CCB0.5%. However, the highest total N (1.43?g kg^?1) was by NPK treatment. The biochar increased plant available water contents, water contents at field capacity and permanent wilting point, soil porosity and decreased bulk density. The highest stable aggregates were in SDB0.5%+CCB0.5%. Biochar application was found as a useful practice for soil sustainability     

Soil boron status: impact of lime and fertilizers in an Indian long-term field experiment on a Typic Paleustalf

In Indian agriculture, nitrogen (N) and phosphorus (P) fertilizers are predominantly used by the farmers, often ignoring secondary and micronutrients. Significance of boron (B) in nutrient management studies has been increasingly underlined under intensive cropping systems particularly in acid soils. In order to understand the distribution of soil native B in different fractions and their contribution to plant B uptake as influenced by nutrient management, soil samples collected after wheat (2009–2010) from a long-term experiment (LTE) continuing since 1972–1973 on Typic Paleustalf of Ranchi were subjected to sequential fractionation of soil B. Treatments included N alone, NP, NPK, 150% of recommended NPK, NPK + farmyard manure (FYM), NPK + lime, and an unfertilized-control. Five soil B fractions were determined along with hot CaCl₂-extractable (available) B. Averaged across the treatments, the soil had low organic carbon (C), pH and cation exchange capacity (CEC), and high free sesquioxides. Total B content was 21.7 mg kg^?1. Among different B fractions, residual B was the major contributor to total B and other fractions collectively shared 7% of total B only. Application of N alone depleted readily soluble, specifically adsorbed and organically bound B bringing the contents even below unfertilized-control. Conjoint use of lime or FYM with NPK increased significantly these fractions, whereas a decrease in oxide bound B was noticed under these treatments. Available B was positively correlated with these fractions indicating their significance in controlling B availability in the soil. The study revealed that use of lime or FYM helped modifying the distribution of soil B in different fractions by way of changing soil pH and organic C content, resulting in enrichment of plant available pool. A drastically low available B content in different treatments receiving fertilizers alone, however, suggested the necessity of B fertilization at prescribed rates for maintaining soil B fertility as also high crop yields.     

Influence of Soil and Fertilizer Nutrients on Sustainability of Rainfed Finger Millet Yield and Soil Fertility in Semi-arid Alfisols

Productivity of rainfed finger millet in semiarid tropical Alfisols is predominantly constrained by erratic rainfall, limited soil moisture, low soil fertility, and less fertilizer use by the poor farmers. In order to identify the efficient nutrient use treatment for ensuring higher yield, higher sustainability, and improved soil fertility, long term field experiments were conducted during 1984 to 2008 in a permanent site under rainfed semi-arid tropical Alfisol at Bangalore in Southern India. The experiment had two blocks—Farm Yard Manure (FYM) and Maize Residue (MR) with 5 fertilizer treatments, namely: control, FYM at 10 t ha^?1, FYM at 10 t ha^?1 + 50% NPK [nitrogen (N), phosphorus (P), potassium (K)], FYM at 10 t ha^?1 + 100% NPK (50 kg N + 50 kg P + 25 kg K ha^?1) and 100% NPK in FYM block; and control, MR at 5 t ha^?1, MR at 5 t ha^?1 + 50% NPK, MR at 5 t ha^?1 + 100% NPK and 100% NPK in MR block. The treatments differed significantly from each other at p < 0.01 level of probability in influencing finger millet grain yield, soil N, P, and K in different years. Application of FYM at 10 t ha^?1 + 100% NPK gave a significantly higher yield ranging from 1821 to 4552 kg ha^?1 with a mean of 3167 kg ha^?1 and variation of 22.7%, while application of maize residue at 5 t ha^?1 + 100% NPK gave a yield of 593 to 4591 kg ha^?1 with a mean of 2518 kg ha^?1 and variation of 39.3% over years. In FYM block, FYM at 10 t ha^?1 + 100% NPK gave a significantly higher organic carbon (0.45%), available N (204 kg ha^?1), available P (68.6 kg ha^?1), and available K (107 kg ha^?1) over years. In maize residue block, application of MR at 5 t ha^?1 + 100% NPK gave a significantly higher organic carbon (0.39%), available soil N (190 kg ha^?1), available soil P (47.5 kg ha^?1), and available soil K (86 kg ha^?1). The regression model (1) of yield as a function of seasonal rainfall, organic carbon, and soil P and K nutrients gave a predictability in the range of 0.19 under FYM at 10 t ha^?1 to 0.51 under 100% NPK in FYM block compared to 0.30 under 100% NPK to 0.67 under MR at 5 t ha^?1 application in MR block. The regression model (2) of yield as a function of seasonal rainfall, soil N, P, and K nutrients gave a predictability in the range of 0.11 under FYM at 10 t ha^?1 to 0.52 under 100% NPK in FYM block compared to 0.18 under MR at 5 t ha^?1 + 50% NPK to 0.60 under MR at 5 t ha^?1 application in MR block. An assessment of yield sustainability under different crop seasonal rainfall situations indicated that FYM at 10 t ha^?1 + 100% NPK was efficient in FYM block with a maximum Sustainability Yield Index (SYI) of 41.4% in <500 mm, 64.7% in 500–750 mm, 60.2% in 750–1000 mm and 60.4% in 1000–1250 mm rainfall, while MR at 5 t ha^?1 + 100% NPK was efficient with SYI of 29.6% in <500 mm, 50.2% in 500–750 mm, 40.6% in 750–1000 mm, and 39.7% in 1000–1250 mm rainfall in semi-arid Alfisols. Thus, the results obtained from these long term studies incurring huge expenditure provide very good conjunctive nutrient use options with good conformity for different rainfall situations of rainfed semiarid tropical Alfisol soils for ensuring higher finger millet yield, maintaining higher SYI, and maintaining improved soil fertility.     

Effects of Continuous Use of Chemical Fertilizers and Manure on Soil Fertility and Productivity of Maize–Wheat under Rainfed Conditions of the Western Himalayas

Long-term effects of continuous use of chemical fertilizers and manure on soil fertility and productivity of a maize–wheat system were investigated in the ongoing long-term fertilizer experiment, during rabi (2007–2008) and kharif (2008) seasons at the research farm of Chaudhary Sarwan Kumar Himachal Pradesh Agricultural University–Hill Agricultural Research and Extension Centre, Dhaulakuan. After 16 cropping cycles, bulk density decreased in plots where farmyard manure (FYM) was applied, whereas pH decreased in all the treatments. The organic carbon content of the soil increased in all the treatments except 100% nitrogen (N). Cation exchange capacity (CEC) increased in all the treatments over the initial status of the soil. Available N showed buildup over the initial status in most of the treatments. Available phosphorus (P) declined from initial status in treatments where only N was applied alone or with FYM. There was reduction in available potassium (K) status in all the treatments except 100% NPK. Continuous addition of FYM with balanced application of inorganic fertilizers improved content of exchangeable calcium (Ca) and magnesium (Mg) over initial status compared to imbalanced application of fertilizers. Continuous use of imbalanced inorganic fertilizers resulted in lesser crop yields and nutrient uptake compared to that with the application of balanced dose of inorganic fertilizers with FYM.     

Effect of short-term supply of farmyard manure on maize growth and soil parameters in pot culture

Farmyard manure (FYM) improves various soil parameters and to a large extent, the availability of water and nutrient to crops when it is applied to the soil. This study aims to further investigate the short-term effects of different levels of FYM on maize plants and soil parameters. Maize plants grown in pot culture were treated with no FYM (control), recommended NPK (inorganic fertilizers), and FYM at 2, 4, 6, 8, and 10 t ha^?1 along with recommended NPK, and the cultures were analyzed 8 weeks after germination. Soil bulk density and soil pH decreased with the increasing levels of FYM, whereas soil porosity, soil organic matter (SOM), soil water content, plant height, root and shoot yield, and NPK uptake of maize were increased compared with the control or recommended NPK, respectively. The present results indicate that short-term application of higher FYM levels improves soil properties. Furthermore, the application of FYM at only higher rates significantly increases the nutrient uptake of maize plants due to improved soil properties. The supply of different amounts of nutrients increases biomass and nutrient uptake in plants.     

Effects of combined organic manure and mineral fertilization on soil aggregation and aggregate-associated organic carbon in two agricultural soils

Abstract

The effect of organic manure and inorganic fertilizer on soil aggregate size distribution and stability, and associated carbon (C) within aggregates varies greatly in previous studies because of the differences in soil conditions, cropping systems, and management practices. This study was conducted as two field fertilization experiments, with different cropping systems, under a subtropical climate in China. The two field experiment sites were located in Jinhua (established in April 2011) in the Jinqu basin in Zhejiang province and Jintan (established in October 2010) in the low-middle Yangtze River plain in Jiangsu province. Both experiments consisted of four treatments, including unfertilized (CK), mineral fertilizer nitrogen (N)–phosphorus (P)–potassium (K) (NPK), NPK plus straw (NPK?+?SR), and NPK plus cattle manure (NPK?+?FYM) or half NPK plus cattle manure (1/2NPK?+?FYM). Water stable aggregate size classes (>5, 2–5, 1–2, 0.5–1, 0.25–0.5, and <0.25?mm) and associated soil organic C (SOC) at 0–15?cm depth were measured. The mean weight diameter (MWD), geometric mean diameter (GMD), and water stable aggregates (WSA)?>?0.25?mm were also determined. The results showed that aggregate-size distribution varied with soil types. Combined application of NPK and organic matter (straw residue or cattle manure), unlike the CK and NPK treatments, significantly increased the WSA >0.25?mm, MWD, and GMD, while obviously reducing the proportion of <0.25?mm aggregates. However, no differences in WSA >0.25?mm, MWD, GMD, and associated C were observed between CK and NPK at both sites. The addition of FYM to the NPK treatment yielded the highest SOC contents in bulk soil, and showed significantly higher associations of C within all size aggregates at both sites. In contrast, NPK?+?SR significantly increased SOC within aggregate classes (2–5?mm, 0.5–1?mm, 0.25–0.5?mm, and <0.25?mm) at Jinhua and (>5?mm and 1–2?mm) at Jintan compared to the CK and NPK treatments. Overall, the combined application of FYM and mineral NPK was the best sustainable management practice for the improvement of aggregate stability and SOC sequestration.