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1.
ABSTRACT

An experiment was replicated simultaneously at two sites of floodplain soils of Bangladesh to find out the optimum application rate of zinc and boron fertilizers for crops under cauliflower-maize-transplant aus rice pattern. Randomized complete block design with three replications was used in the experimentation. The first crop of the pattern received four zinc levels (0, 2.0, 4.0, and 6.0 kg ha?1), and three boron levels (0, 1.5, and 3.0 kg ha?1). In second crop, two additional treatments receiving 2.0 kg Zn ha?1 and 2.0 kg Zn ha?1 + 1.5 B ha?1 were added; in the third crop, another four treatments were added by further application of 2 kg Zn ha?1 in each. Other nutrients viz. N, P, K, and S were used equally at recommended rates for all plots. In such a 3-crop pattern, application of 4.0 kg Zn ha?1 and 1.5 kg B ha?1 at a time to the first crop or 2.0 kg Zn ha?1 to each of the first two crops along with 1.5 kg B ha?1 to the first crop was sufficient to achieve satisfactory yield of the crops. Considering system productivity, nutrient uptake, and protein and Zn concentrations of crops, the aforesaid doses were found promising.  相似文献   

2.
Field experiments were conducted to study the response of cotton genotypes (G. arboreum Bt cv. RCH 650 BGII; non-Bt cv. F 2228; G. herbaceum cv. FDK 124) and wheat and triticale genotypes (T. aestivum cv. PBW 622; T. durum cv. PDW 314; triticale cv. TL 2908) to direct and residual B application (0, 0.5, 1.0, and 2.0 kg B ha?1 as borax) using a Typic Ustrochrept, neutral, noncalcareous, loamy sand and B-deficient soil. A significant response of 218 and 231 kg ha?1 in seed cotton yield was recorded with an application of 1.0 kg B ha?1 to cotton and 2.0 kg B ha?1 to wheat. A significant response of 152 kg ha?1 grain yield of wheat was observed with the application of 0.5 kg B ha?1 to wheat, while no residual effect of B was observed when B was applied to cotton. On the basis of agronomic and B uptake efficiency, genotypes of cotton (RCH 650 BG II > FDK 124 > F 2228) and wheat (PDW 314> TL 2908> PBW 621) responded differentially to B application, thus indicating that yield of Bt cotton and durum wheat will be reduced more than the other cultivars under B deficiency.  相似文献   

3.
Abstract

Pot studies were conducted to study effect of the boron (B) levels (0, 0.12, 0.25, 0.50, 0.75, 1.0, 2.0 3.0, 4.0, 5.0 and 10?mg?B?kg?1) and calcium carbonate (CaCO3) (0, 1.25, 2.5 and 5.0%) on cotton and wheat crops in cropping system. In absence of CaCO3, reduced growth of cotton and wheat were observed when B was applied @ 2.0?mg?kg?1 soil. Necrosis of leaves in cotton and purple coloration of plumule in wheat was observed @ 10.0?mg?B?kg?1. Irrespective of CaCO3, 0.57 and 7.67?mg?kg?1 Hot Water Soluble B (HWS-B), 62 and 940?mg?kg?1 B dry matter (DM) of leaves, 45 and 210?mg?B?kg?1 DM of petioles and 20 and 51?mg?B?kg?1 DM of sticks, produced 90 and 50%of the maximum dry matter yield (DMY) of cotton, respectively. The values for wheat were 0.66 and 6.71?mg HWS-B kg?1, 7.94 and 27.0?mg?B?kg?1 grain and 15.3 and 170?mg?B?kg?1 straw, respectively.  相似文献   

4.
Abstract

A field experiment was conducted at Horticultural Experimental Farm, Assam Agricultural University, Jorhat during the year 2015–17 to assess the impact of boron fertilization on dynamics of boron fractions in soil and crop yields in cauliflower–cowpea–okra cropping sequence. Five levels of boron (0, 0.5, 1.0, 1.5 and 2.0?kg ha?1) along with the recommended dose of NPK fertilizer were applied in soil in cauliflower once in each 2 years (2015–17) of experimentation to assess the direct effect of boron fertilization, while cowpea and okra were grown as a suceeding test crop to study the residual effects of boron fertilization in the cropping sequence. Among the different levels of boron, the highest content of all the boron fractions in soil was recorded at rate of 2?kg B ha?1 at different crop growth stages for all the three crops. Progressive decrease in content of all the boron fractions with crop ageing was noticed. The content of different boron fractions in soil follows the order readily soluble boron (RSB)<oxide bound boron (OXB)<organic bound boron (ORBB)<specifically adsorbed boron (SAB) <residual boron, respectively. The boron level of 2?kg B ha?1 was found to prominent in increasing the yield in all the crops. In respect of contributions of different boron fractions to yield of crops, oxide bound boron(2.10) was found to be the highest contributor of cauliflower yield, while the residual boron (1.10), contributed the highest to cowpea yield and organic bound boron fraction (1.24) was found to be most prominent contributor of boron in leveraging okra yield.  相似文献   

5.
Abstract. Three successive crops of winter wheat were grown on a sandy loam to test the residual effect of long‐term annual incorporation of spring barley straw at rates of 0, 4, 8 and 12 t ha?1, and ryegrass catch crops with or without additions of pig slurry. Soil receiving 4, 8 and 12 t ha?1 of straw annually for 18 years contained 12, 21 and 30% more carbon (C), respectively, than soil with straw removal, and soil C and nitrogen (N) contents increased linearly with straw rate. The soil retained 14% of the straw C and 37% of the straw N. Ryegrass catch‐cropping for 10 years also increased soil C and N concentrations, whereas the effect of pig slurry was insignificant. Grain yield in the first wheat crop showed an average dry matter (DM) increase of 0.7 t ha?1 after treatment with 8 and 12 t straw ha?1. In the two subsequent wheat crops, grain yield increased by 0.2–0.3 t DM ha?1 after 8 and 12 t straw ha?1. No grain yield increases were found after 4 t straw ha?1 in any of the three years. Previous ryegrass catch crops increased yields of wheat grain, but effects in the third wheat crop were significant only where ryegrass had been combined with pig slurry. Straw incorporation increased the N offtake in the first wheat crop. In the second crop, only 8 and 12 t straw ha?1 improved wheat N offtake, while the N offtake in the third wheat crop was unaffected. Ryegrass catch crops increased N offtake in the first and second wheat crop. Again, a positive effect in the third crop was seen only when ryegrass was combined with slurry. Long‐term, annual incorporation of straw and ryegrass catch crops provided a clear and relatively persistent increase in soil organic matter levels, whereas the positive effects on the yield of subsequent wheat crops were modest and transient.  相似文献   

6.
Boron (B) is an essential microelement, which is necessary for reproductive organs including pollen tube formation in wheat (Triticum aestivum L.), and flowering and boll formation in cotton (Gossypium hirsutum L.) The study was associated with wheat-cotton rotation in 80 farm fields, belonging to different soil series, in four districts of cotton belt of Punjab, Pakistan to assess concentrations of extractable B in soils [0.05 M hydrochloric acid (HCl) extractable B], and added fertilizer B and their relationship to some soil physico-chemical properties [pH, organic matter (OM), calcium carbonate (CaCO3) and clay content], yields and total B concentrations in wheat and cotton plants. All soils had alkaline pH (7.45 to 8.55), high CaCO3 content (2.14 to 8.65%), less than 1.0% OM (0.33 to 0.99%), low plant available-P (Olsen P less than 8 mg kg?1 soil) and medium ammonium acetate extractable potassium (K) (< 200 mg K kg?1 soil). Of the 80 soil samples, 65 samples (81%) were low in available B (<0.45 mg B kg?1, ranging from 0.11 to 0.43 mg B kg?1) Of the corresponding 80 plant samples, leaves B concentrations were below critical levels (<10 mg B kg?1 for wheat; <30 mg B kg?1 for cotton) for all the tested samples for wheat and cotton. The regression analysis between plant total B concentrations and soil extractable B concentrations showed strong linear positive relationships for both wheat (R2 = 0.509***, significant at P <0.001) and cotton (R2 = 0.525***, significant at P <0.001). Further regression analysis between extractable soil B and wheat grain yield as well as between wheat leaves total B and wheat grain yield also depicted strong linear relationships (R2 = 0.76 and 0.42, respectively). Boron fertilizer demonstration plots laid out at farmers’ fields low in extractable B, in each district not only enhanced grain yields of wheat crop but also contributed a significant increase towards seed cotton yield of succeeding cotton crop through residual B effect. In conclusion, the findings suggest that many soils in the cotton belt of Punjab may be low in extractable B for wheat and cotton, especially when these crops are grown on low OM soils with high CaCO3 content.  相似文献   

7.
A long-term field experiment was conducted for 8 years on a Vertisol in central India to assess quantitatively the direct and residual N effects of soybean inoculation with Bradyrhizobium and wheat inoculation with Azotobacter in a soybean–wheat rotation. After cultivation of soybean each year, its aerial residues were removed before growing wheat in the same plots using four N levels (120, 90, 60 and 30 kg ha?1) and Azotobacter inoculation. Inoculation of soybean increased grain yield by 10.1% (180 kg ha?1), but the increase in wheat yields with inoculation was only marginal (5.6%; 278 kg ha?1). There was always a positive balance of soil N after soybean harvest; an average of +28 kg N ha?1 yr?1 in control (nodulated by native rhizobia) plots compared with +41 kg N ha?1 yr?1 in Rhizobium-inoculated plots. Residual and direct effects of Rhizobium and Azotobacter inoculants caused a fertilizer N credit of 30 kg ha?1 in wheat. Application of fertilizers or microbial inoculation favoured the proliferation of rhizobia in crop rhizosphere due to better plant growth. Additional N uptake by inoculation was 14.9 kg N ha?1 by soybean and 20.9 kg N ha?1 by wheat crop, and a gain of +38.0 kg N ha?1 yr?1 to the 0–15 cm soil layer was measured after harvest of wheat. So, total N contribution to crops and soil due to the inoculants was 73.8 kg N ha?1 yr?1 after one soybean–wheat rotation. There was a total N benefit of 13.8 kg N ha?1 yr?1 to the soil due to regular long-term use of microbial inoculants in soybean–wheat rotation.  相似文献   

8.
Abstract

As part of a project to stimulate Norwegian seed production of common bent (syn. browntop, US: colonial bentgrass, Agrostis capillaris L. syn. A.tenuis Sibth.) field trials comparing sowing rates of 2.5, 5.0, 7.5 or 10 kg ha?1 were conducted at Landvik, south-east Norway, (58°N) from 1989 to 1994. Three trials were laid out of the forage cultivar ‘Leikvin’ and three trials of the lawn cultivar ‘Nor’, each trial being harvested for three consecutive years. While the average per cent ground cover in spring increased from 87% at 2.5 kg ha?1 to 94–96% at 7.5 kg ha?1, seed yields decreased with increasing sowing rate in both cultivars. On average for all harvests, quadrupling the sowing rate from 2.5 to 10 kg ha?1 reduced seed yield by 9% in ‘Leikvin’ and 15% in ‘Nor’, the stronger effect probably being associated with a greater competition between tillers in the lawn cultivar. Seed yield reductions with increasing sowing rate showed no relationship with crop age, but were less accentuated for crops undersown in spring wheat in a dry year than for crops established without cover crop in years with ample rainfall in early summer. Increasing sowing rates reduced plant height and panicle number in ‘Nor’, but had no effect on seed weight or germination in any of the cultivars. It is concluded that seed crops of common bent should be established with a sowing rate of 2–5 kg ha?1, with the lowest rate in lawn cultivars, under ideal seedbed conditions and when seed crops are sown without cover crop.  相似文献   

9.
Abstract

A two-year field experiment was conducted to investigate the impact of short crop rotation and organic amendments on rapeseed yield under weed competition conditions. The primary experimental plots consisted of either triticale or pea as a prior crop, consisting of four subplots with either 25 tons of composted cattle manure (CCM), 150?kg urea N ha?1 (N), 25 tons composted cattle manure + 75?kg urea N ha?1 (CCM?+?N), or no urea N or manure added as the control (C0). Rapeseed seed yield was not significantly affected by previous crops, except for rapeseed grown after pea which had slightly higher seed yield (2058?kg ha?1) than those grown after triticale (1942?kg ha?1). Plants that received CCM?+?N produced the highest amount of seed yield (2447?kg ha?1), but were not significantly different from plants that received just urea N (2218?kg ha?1). Weeds gained more biomass when the previous crop was pea compared to those whose previous crop was triticale. Weeds in plots that received CCM?+?N produced the greatest biomass, followed by N, and CCM plots, respectively.  相似文献   

10.
ABSTRACT

Field experiments were carried out for three consecutive years (2003–2006) at Bangladesh Sugarcane Research Institute farm soil on plant (first crop after planting) and subsequent two ratoon crops of sugarcane. The main objectives of the study were to assess the direct and residual effects of organic and inorganic fertilizer on growth, yield, and juice quality of plant and ratoon crops. The plant crop consisted of four treatments. After harvesting of plant crop to evaluate the residual effects on ratoon crop the plots were subdivided except the control plot. Thus, there were seven treatments in the ratoon crop. Application of recommended fertilizer [nitrogen (N150), phosphorus (P52), potassium (K90), sulfur (S35), and zinc (Zn3) kg ha? 1] singly or 25% less of it either with press mud or farmyard manure (FYM) at 15 t ha? 1 produced statistically identical yield ranged from 67.5 to 69.0 t ha? 1 in plant crop. In the ratoon experiment when the recommended fertilizer was applied alone or 25% less of its either with press mud or FYM at 15 or even 7.5 t ha? 1 again produced better yield; it ranged from 64.8 to 69.2 in first ratoon and 68.2 to 76.5 t ha? 1 in second ratoon crops. Results showed that N, P, K, and S content in leaf progressively decreased in ratoon crops over plant crop. Juice quality parameters viz. brix, pol, and purity % remained unchanged both in plant and ratoon crops. Furthermore, organic carbon (C), available N, P, K, and S were higher in post harvest soils that received inorganic fertilizer in combination with organic manure than control and inorganic fertilizer treated soil. It may be concluded that the application of 25% less of recommended fertilizer (N112, P40, K68, S26, and Zn2.2.5 kg ha? 1) either with press mud or FYM at 15 t ha? 1 was adequate for optimum yield of plant crop. Results also suggest that additional N (50% extra dosage) keeping all other fertilizers at the same level like plant crop i.e. N168, P40, K68, S26, and Zn2.25 kg ha? 1 either with press mud or FYM at 7.5 t ha? 1 may be recommended for subsequent ratoon crops to obtain good yield without deterioration in soil fertility.  相似文献   

11.
Abstract

Quantitative assessment of soil nitrogen (N) that will become available is important for determining fertilizer needs of crops. Nitrogen‐supplying capacity of soil to rice and wheat was quantified by establishing zero‐N plots at on‐farm locations to which all nutrients except N were adequately supplied. Nitrogen uptake in zero‐N plots ranged from 41.4 to 110.3 kg N ha?1 for rice and 33.7 to 123.4 kg N ha?1 for wheat. Availability of soil N was also studied using oxidative, hydrolytic, and autoclaving indices, salt‐extraction indices, light‐absorption indices, and aerobic and anaerobic incubation indices. These were correlated with yield and N uptake by rice and wheat in zero‐N plots. Nitrogen extracted by alkaline KMnO4 and phosphate borate buffer and nitrogen mineralized under aerobic incubation were satisfactory indices of soil N supply. For rice, 2 M KCl and alkaline KMnO4 were the best N‐availability indices. Thus, alkaline KMnO4 should prove a quick and reliable indicator of indigenous soil N supply in soils under a rice–wheat cropping system.  相似文献   

12.
ABSTRACT

In sorghum and mungbean – lentil cropping system, field experiments were conducted for three successive years to assess the effect of mung bean residue incorporation on sorghum and succeeding lentil productivity along with different doses of phosphorus (P; 0, 30, 60 kg ha? 1) applied to these crops. The level of soil fertility was also tested with or without incorporation of mung bean residue. The interaction of phosphorus to mungbean residue incorporation was thus studied in relation to improve crop productivity with balancing fertilizer requirements through an eco-friendly approach. Sorghum grain yield increased significantly when 60 kg P2O5 ha? 1 was applied and mungbean residue incorporated. The response was reduced to 30 kg P2O5 ha? 1 when mungbean residue was not incorporated. The succeeding lentil crop responded up to 60 kg P2O5 ha? 1 only when preceding sorghum crop received 0 or 30 kg P2O5 ha? 1. Response to applied P2O5 to lentil reduced to 30 kg ha? 1 when preceding sorghum crop received 60 kg P2O5 ha? 1 and mungbean residue incorporated. Available soil nitrogen, phosphorus, and organic carbon content increased when mungbean residue was incorporated; however, available potassium (K) of the soil decreased from its initial value.  相似文献   

13.
Agricultural productivity is increasingly becoming dependent upon soil fertility, which is generally thought to be supplemented through the application of nutrients mainly through inorganic fertilizers. The present study aims to characterize the soil physical environment in relation to long-term application of farmyard manure (FYM) and inorganic fertilizers in a maize–wheat cropping system. The treatments in both the maize and wheat systems included a control (without any fertilizer or FYM), FYM (farmyard manure at 20 t ha?1), N100 (nitrogen at 100 kg ha?1), N100P50 (nitrogen and phosphorus at 100 and 50 kg ha?1), and N100P50K50 (nitrogen, phosphorus, and potash at 100, 50, and 50 kg ha?1). The treatments were replicated four times in a randomized complete block design in sandy loam soil. The root mass density in surface layers of both the crops was lower in FYM and higher in inorganic fertilizer plots. The root length density was found to be highest in FYM-treated plots and lowest in control plots. The periodic soil matric suction during wheat following maize remained highest in FYM plots followed by that in N100 plots in all the layers. The soil water storage of wheat at harvest (rice–wheat) was highest (21.1 cm) in control and lowest (17.8 cm) in FYM-treated plots. The soil water status, root growth, and crop performance improved with balanced fertilization.  相似文献   

14.
Long-term effects of the different combinations of nutrient-management treatments were studied on crop yields of sorghum + cowpea in rotation with cotton + black gram. The effects of rainfall, soil temperature, and evaporation on the status of soil fertility and productivity of crops were also modeled and evaluated using a multivariate regression technique. The study was conducted on a permanent experimental site of rain-fed semi-arid Vertisol at the All-India Coordinated Research Project on Dryland Agriculture, Kovilpatti Centre, India, during 1995 to 2007 using 13 combinations of nutrient-management treatments. Application of 20 kg nitrogen (N) (urea) + 20 kg N [farmyard manure (FYM)] + 20 kg phosphorus (P) ha?1 gave the greatest mean grain yield (2146 kg ha?1) of sorghum and the fourth greatest mean yield (76 kg ha?1) of cowpea under sorghum + cowpea system. The same treatment maintained the greatest mean yield of cotton (546 kg ha?1) and black gram (236 kg ha?1) under a cotton + cowpea system. When soil fertility was monitored, this treatment maintained the greatest mean soil organic carbon (4.4 g kg?1), available soil P (10.9 kg ha?1), and available soil potassium (K) (411 kg ha?1), and the second greatest level of mean available soil N (135 kg ha?1) after the 13-year study. The treatments differed significantly from each other in influencing soil organic carbon (C); available soil N, P, and K; and yield of crops attained under sorghum + cowpea and cotton + black gram rotations. Soil temperature at different soil depths at 07:20 h and rainfall had a significant influence on the status of soil organic C. Based on the prediction models developed between long-term yield and soil fertility variables, 20 kg N (urea) + 20 kg N (FYM) + 20 kg P ha?1 could be prescribed for sorghum + cowpea, and 20 kg N (urea) + 20 kg N (FYM) could be prescribed for cotton + black gram. These combinations of treatments would provide a sustainable yield in the range of 1681 to 2146 kg ha?1 of sorghum, 74 to 76 kg ha?1 of cowpea, 486 to 546 kg ha?1 of cotton, and 180 to 236 kg ha?1 of black gram over the years. Beside assuring greater yields, these soil and nutrient management options would also help in maintaining maximum soil organic C of 3.8 to 4.4 g kg?1 soil, available N of 126 to 135 kg ha?1, available soil P of 8.9 to 10.9 kg ha?1, and available soil K of 392 to 411 kg ha?1 over the years. These prediction models for crop yields and fertility status can help us to understand the quantitative relationships between crop yields and nutrients status in soil. Because black gram is unsustainable, as an alternative, sorghum + cowpea could be rotated with cotton for attaining maximum productivity, assuring sustainability, and maintaining soil fertility on rain-fed semi-arid Vertisol soils.  相似文献   

15.
A study was conducted to assess fertilizer effect on pearl millet–wheat yield and plant-soil nutrients with the following treatments: T1, control; T2, 100% nitrogen (N); T3, 100% nitrogen and phosphorus (NP); T4, 100% nitrogen, phosphorus and potassium (NPK); T5, 100% NPK + zinc sulfate (ZnSO4) at 25 kg ha?1; T6, 100% NPK + farmyard manure (FYM) at 10 t ha?1; T7, 100% NPK+ verimcompost (VC) at 2.5 tha?1; T8, 100% NPK + sulfur (S) at 25 kg ha?1; T9, FYM at 10 t ha?1; T10, VC at 2.5 t ha?1; T11, 100% NPK + FYM at 10 t ha?1 + 25 kg S ha?1 + ZnSO4 at 25 kg ha?1; and T12, 150% NPK treatments. Treatments differed significantly in influencing soil-plant nutrients and grain and straw yields of both crops. Grain yield had significant correlation with soil-plant N, P, K, S, and zinc (Zn) nutrients. The study indicated superiority of T11 for attaining maximum pearl millet grain yield (2885 kg ha?1) and straw yield (7185 kg ha?1); amounts of N (48.9 kg ha?1), P (8.8 kg ha?1), K (26.3 kg ha?1), S (20.6 kg ha?1), and Zn (0.09 kg ha?1) taken up; and amounts of soil N (187.7 kg ha?1), P (13.7 kg ha?1), K (242.5 kg ha?1), S (10.1 kg ha?1), and Zn (0.70 kg ha?1). It was superior for wheat with grain yield (5215 kg ha?1) and straw yield (7220 kg ha?1); amounts of N (120.7 kg ha?1), P (13.8 kg ha?1), K (30 kg ha?1), S (14.6 kg ha?1), and Zn (0.18 kg ha?1) taken up; and maintaining soil N (185.7 kg ha?1), P (14.5 kg ha?1), K (250.5 kg ha?1), S (10.6 kg ha?1), and Zn (0.73 kg ha?1). Based on the study, 100% NPK + FYM at 10 tha?1 + Zn at 25 kg ha?1 + S at 25 kg ha?1 could be recommended for attaining maximum returns of pearl millet–wheat under semi-arid Inceptisols.  相似文献   

16.
《Journal of plant nutrition》2013,36(8):1561-1580
Abstract

The Magruder plots are the oldest continuous soil fertility wheat research plots in the Great Plains region, and are one of the oldest continuous soil fertility wheat plots in the world. They were initiated in 1892 by Alexander C. Magruder who was interested in the productivity of native prairie soils when sown continuously to winter wheat. This study reports on a simple estimate of nitrogen (N) balance in the Magruder plots, accounting for N applied, N removed in the grain, plant N loss, denitrification, non‐symbiotic N fixation, nitrate (NO3 ?) leaching, N applied in the rainfall, estimated total soil N (0–30 cm) at the beginning of the experiment and that measured in 2001. In the Manure plots, total soil N decreased from 6890 kg N ha?1 in the surface 0–30 cm in 1892, to 3198 kg N ha?1 in 2002. In the Check plots (no nutrients applied for 109 years) only 2411 kg N ha?1 or 35% of the original total soil organic N remains. Nitrogen removed in the grain averaged 38.4 kg N ha?1 yr?1 and N additions (manure, N in rainfall, N via symbiotic N fixation) averaged 44.5 kg N ha?1 yr?1 in the Manure plots. Following 109 years, unaccounted N ranged from 229 to 1395 kg N ha?1. On a by year basis, this would translate into 2–13 kg N ha?1 yr?1 that were unaccounted for, increasing with increased N application. For the Manure plots, the estimate of nitrogen use efficiency (NUE) (N removed in the grain, minus N removed in the grain of the Check plots, divided by the rate of N applied) was 32.8%, similar to the 33% NUE for world cereal production reported in 1999.  相似文献   

17.
Swine lagoon sludge is commonly applied to soil as a source of nitrogen (N) for crop production but the fate of applied N not recovered from the soil by the receiver crop has received little attention. The objectives of this study were to (1) assess the yield and N accumulation responses of corn (Zea mays L.) and wheat (Triticum aestivum) to different levels of N applied as swine lagoon sludge, (2) quantify recovery of residual N accumulation by the second and third crops after sludge application, and (3) evaluate the effect of different sludge N rates on nitrate (NO3-N) concentrations in the soil. Sludge N trials were conducted with wheat on two swine farms and with corn on one swine farm in the coastal plain of North Carolina. Agronomic optimum N rates for wheat grown at two locations was 360 kg total sludge N ha?1 and the optimum N rate for corn at one location was 327 kg total sludge N ha?1. Residual N recovered by subsequent wheat and corn crops following the corn crop that received lagoon sludge was 3 and 12 kg N ha?1, respectively, on a whole-plant basis and 2 and 10 kg N ha?1, respectively, on a grain basis at the agronomic optimum N rate for corn (327 kg sludge N ha?1). From the 327 kg ha?1 of sludge N applied to corn, 249 kg N ha?1 were not recovered after harvest of three crops for grain. Accumulation in recalcitrant soil organic N pools, ammonia (NH3) volatilization during sludge application, return of N in stover/straw to the soil, and leaching of NO3 from the root zone probably account for much of the nonutilized N. At the agronomic sludge N rate for corn (327 kg N ha?1), downward movement of NO3-N through the soil was similar to that for the 168 kg N ha?1 urea ammonium nitrate (UAN) treatment. Thus, potential N pollution of groundwater by land application of lagoon sludge would not exceed that caused by UAN application.  相似文献   

18.
ABSTRACT

Crop production in arid regions is characterized with high temperature, drought and salinity which decrease water and nutrient use efficiency. This study was conducted to investigate the effect of wheat residue mulch in relation to N fertilizer application rates for cotton productivity under dryland condition of Uzbekistan. Main plots were control of no mulch addition and a 5 t ha?1 mulch treatment. These plots were split into 5 N rate plots of 0, 70, 140, 210 or 280 kg of N ha?1. The results showed that mulching pattern decreased soil temperature by 0.7–1.5°C as compared to conventional treatment (CT), regardless of N fertilization rates. The soil water storage increased by 41.8, 17.3, 48.0 mm in the flowering, boll formation and ripening stages of cotton, respectively under mulching treatment. Soil available N concentration and nutrients uptake by plants consistently increased with the increase of N fertilization rates with positive correlations. At flowering period, the plant height, chlorophyll content, stem diameter, and a number of fruit branches in plants were higher by 32.3%, 46.8%, 26.7% and 55.3%, respectively at 210 kg N ha?1 under mulching treatment as compared to the non-fertilized control. The highest cotton yield was obtained at 210 kg N ha?1 application under mulching treatment. The correlation difference between mulch and N application rates was higher (R2 = 0.97) than the difference in CTs and N application rates (R2 = 0.89). This study showed that mulching had a greater impact to preserve nutrients and water resources in the soil, thereby improved cotton growth and yield.  相似文献   

19.
Abstract

Efficient nutrient and water use are two important considerations to obtain good harvests of wheat. This necessitates the development of an effective nutrient management technique that not only increases yield, but simultaneously can save nutrient and water use. In this context, a field experiment was conducted at Indian Agricultural Research Institute, New Delhi, India to evaluate the residual effect of sesbania and rice bean (in-situ), subabul (ex-situ) green manuring and Zinc (Zn) fertilization, using chelated Zn-ethylenediaminetetraacetic acid (Zn-EDTA) on nutrient use, yields and water productivity of wheat under rice–wheat cropping system. Among residual effects of green manure crops and Zn fertilization, sesbania and foliar spray of 0.5% chelated Zn-EDTA at 20, 40, 60 and 80 days after sowing (DAS) recorded significantly higher nutrient content and uptake and yields than other green manure crops and Zn treatments. Residual effect of sesbania saved about 46.5?×?103 and 30.5?×?103 L irrigation water per tonne of wheat over subabul and rice bean, respectively. Foliar spray of 0.5% chelated Zn-EDTA at 20, 40, 60 and 80 DAS saved about 55.5?×?103, 47?×?103 and 13?×?103 L irrigation water per tonne wheat over residual effect of 5?kg Zn ha?1 through chelated Zn-EDTA as soil application, 2.5?kg Zn ha?1 through chelated Zn-EDTA as soil application + 1 foliar spray of 0.5% chelated Zn-EDTA at flowering and foliar spray of 0.5% chelated Zn-EDTA at active tillering?+?flowering?+?grain filling, respectively. Correlation analysis showed positive correlation between Zn uptake and grain yield.  相似文献   

20.
ABSTRACT

Field experiments were conducted for 2 years in sandy loam soil, to study the direct effect of organic manures i.e. sewage sludge (SS), vermicompost (VC) and sesbania (SB) and chemical fertilizers on rice (Oryza sativa) and their residual effect on wheat (Triticum aestivum) grown in sequence in winter (Rabi) and summer (Kharif) season during 2015–2016 to 2016–2017 at Varanasi, Uttar Pradesh. Residual effect of organic sources of nutrients as SS, VC and SB were monitored up to fourth crop (II wheat) in sequence applied in conjunction with 75% recommended dose of fertilize (RDF). Among the nutrient sources, the maximum grain yield in I rice (4.89 t ha?1), II rice (4.95 t ha?1), was recorded in treatment T3 (100% RDF with S, Zn, B) whereas in I wheat (4.68 t ha?1) and II wheat (4.59 t ha?1), it was recorded in T4 (customized fertilizer). The maximum straw yield during all four crops was recorded in T3 (100% RDF with S, Zn, B) in rice and T4 (customized fertilizer) in wheat crop, which showed 25, 32, 23 and 28% increase over 100% RDF (T2). Application of 100% RDF along with S, Zn, B and customized fertilizer increased the total uptake of N, P, K, S and B and also in net returns and B:C ratio followed by organic treatments.  相似文献   

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