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1.
Abstract

A wide range of synthetic and natural materials can act as amendments to enhance soil physical properties. Novel materials purporting to be conditioners need to be agronomically evaluated prior to adoption for general use. Of particular concern in semi‐arid regions are those that influence water relations in sandy soils. A polyacrylamid hydrogel, “Aquastock”, was tested in the laboratory for moisture retention under varying environments to simulate field conditions, and in relation to soil properties. A companion greenhouse study considered the influence of both rate and method of application on cucumber yield, and on irrigation frequency. The material increased available water and reduced permeability, especially in the sandy soil. Moisture release under varying soil pressure or matric potential was favorably influenced by the conditioner. The material significantly increased fruit yield and related crop parameters as well as reducing the number of irrigations required; complete mixing with the soil volume was more effective than partial mixing. “Aquastock” appears to have potential in semi‐arid areas and with protected high value cropping. Commercial and economic evaluation is warranted.  相似文献   

2.
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.  相似文献   

3.
Abstract

Natural zeolite (clinoptilolite containing tuff) can be used as an adsorbent of strontium (Sr) from phosphogypsum when applied as a solonetzic soil amendment. This study investigated the influence of the zeolite on biological yield, content of water‐soluble Sr in soil, its availability, and plant uptake. A field experiment was conducted from 1993 to 1995 in the Volgogradskaya region of Russia. Two methods of phosphogypsum and zeolite application were used: “separate” and “as a mixture” (10 tons ha‐1 of phosphogypsum and 0.5 ton ha‐1 of zeolite in both cases). After the application of the amendments, barley (Hordeum vulgare) and grass sorghum (Sorghum sudanensis) were grown on the ameliorated sites in 1994 and 1995, respectively. Our results suggest that zeolite, being applied with phosphogypsum as a mixture, decreased by 15 to 75% the content of water‐soluble Sr in the soil, minimizing the risk of soil pollution. The uptake of Sr by plants depended on the biological character of the crop grown. Barley was found to be a “strong‐anticoncentrative” type of plant. However, grass sorghum was found to be more sensitive to the rise of Sr content in the soil. The highest biomass production of barley and grass sorghum was obtained with the application of zeolite and zeolite plus phosphogypsum. Plants grown on a single phosphogypsum‐treated sites had a declining tendency in biological yield. Our results suggest a positive influence of zeolite applied with phosphogypsum for the amelioration of solonetzic soils on the growth and uptake of Sr by plants.  相似文献   

4.
Abstract

Silicon (Si) is a beneficial nutrient for sugarcane (Saccharum spp.) and yield responses to Si amendment have been determined on soils with low soluble Si. Because a soil test Si calibration has not been published for sugarcane grown on Florida mineral soils, the objectives were to determine sugarcane yield response to silicon soil amendment on two mineral soils (Entisol and Spodosol) and to relate sucrose yield to soil-extractable Si. Calcium silicate application rates were 0, 3.4, and 6.7?Mg ha?1 (Site 1) and 0, 2.2, 4.5, and 6.7?Mg ha?1 (Site 2) in small-plot (120 m2 plot?1) experiments, with Si application resulting in significant increases in biomass and sucrose ha?1. Calcium silicate requirements of 6.7 and 4.3?Mg ha?1 were determined with initial acetic acid-extractable Si of 21 and 46?g m?3, respectively. Nonlinear models indicated that Si amendments will be required with acetic acid-extractable Si <105?g m?3.  相似文献   

5.
Rice production and cyanobacterial N in acid soil can be improved by liming. There is evidence that the organic amendments can increase the soil pH. The aim of this study was to find appropriate combination of soil amendments and cyanobacteria capable for enhancing nutrient uptake and improving rice yield in acidic paddy soil. Three soil amendments (rice straw, sewage‐sludge composts, NPK) with and without inoculation of cyanobacteria were studied for rice plants (Oryza sativa L.) in a pot experiment. The sludge compost had significantly reduced soil acidity from 5.44 to 6.67. The plant N and K uptake increased significantly with sludge and cyanobacteria application. The yield components increased significantly with sludge, but decreased thereafter, an exception was the number of panicles, with straw compost. These characters were also significantly affected by inoculation with cyanobacteria except 100‐grain weight, filled‐grain percentage, and harvest index. The combination of sludge compost and cyanobacteria improved the yield components and consequently grain yield (138 g pot–1) compared with sludge treatment only (132 g pot–1). The amount of cyanobacterial N absorbed (N‐difference method) by rice plant under sludge compost was higher than that of soils amended with either rice straw or NPK treatments. Therefore, the addition of sewage sludge to acid paddy soil not only amended the soil properties but also activated the cyanobacteria and consequently improved rice plant nutrition and grain yield.  相似文献   

6.

Background

Soil aggregation and organic carbon (OC) content are important indicators of soil quality that can be improved with plant residue amendments. The extent of the effects of plant residue amendments on soil aggregation and OC content across different plant residue and soil types is not fully understood.

Aim

In this meta-analysis, we evaluated the effects of plant residue amendments on soil aggregation and OC content for different plant residues (fresh, charred) and soil types varying in clay content, initial OC content, and pH.

Methods

Our meta-analysis included 50 published studies (total of 299 paired observations). We estimated the response ratios of mean weight diameter (MWD) and separate aggregate size classes, total soil OC (TSC), and aggregate-associated OC. We also considered the effect of experimental factors (study duration, residue type, residue amount, initial soil OC, clay content, and pH).

Results

The benefit of plant residue amendment on soil aggregation was larger in soils with initially low OC content and neutral pH. Initial soil OC content and pH were more important than soil clay content for OC storage in soil aggregates. Both fresh and charred plant residue amendments were effective in forming aggregates, whereas charred residues were more effective in increasing TSC. We found only a weak positive relationship between the response ratio of TSC and MWD indicating that other factors besides soil aggregation contributed to the increase in soil C storage.

Conclusions

While plant residue amendments can enhance soil aggregation and TSC, these effects are likely governed by the type of plant residue and soil properties such as the initial soil pH and OC content.  相似文献   

7.
Hardsetting and crusting are forms of soil structure degradation associated with the collapse of macroaggregates during wetting and are responsible for poor seedling emergence, crop establishment and yields of food crops especially in semi-arid environments. This study investigated the effects of applying of 3.0 t ha−1 phosphogypsum, 1.0 t ha−1 polymer gel, 3.0 t ha−1 grass mulch and 5.0 t ha−1 cattle manure to the topsoil (0–15 cm) of a soil with hardsetting and crusting behavior and observed changes on aggregation under field conditions for two consecutive seasons. There were significant improvements in soil aggregate properties in the amended soil over the control. Both aggregate size distribution and wet aggregate stability showed significant differences between the amendments in the two seasons. The mean weight diameters of aggregates were 4.23 mm (mulch), 3.31 mm (manure), 2.17 mm (polymer gel), 2.23 mm (phosphogypsum) and 1.36 mm (control). The aggregates (2–4 mm) from amended soil were consistently more stable than the control and were in the order polymer gel = manure > mulch > gypsum > control. Tensile strength and bulk density of aggregates, on the other hand, were significantly higher (P < 0.05) in the unamended than amended soil.The application of soil amendments, especially mulch, significantly increased the soil water content over the two seasons and this was associated with lower soil penetration resistance in the latter. The reduced soil strength in the amended soils contributed to higher pegging, podding and grain yields of bambara groundnut (Vigna subterranean). This was confirmed by significantly higher correlations between soil aggregate characteristics, soil water, penetrometer resistance and growth and yield of bambara groundnut. The study concluded that significant improvements in soil aggregation can be obtained over a relatively short period and this can improve the yield of food crops.  相似文献   

8.
碱渣与菜籽饼共施对茶园土壤酸度调控的研究   总被引：2，自引：0，他引：2  
Rapeseed cake (RC), the residue of rapeseed oil extraction, is effective for improving tea (Camellia sinensis) quality, especially taste and aroma, but it has limited ability to ameliorate strongly acidic soil. In order to improve the liming potential of RC, alkaline slag (AS), the by-product of recovery of sodium carbonate, was incorporated. Combined effects of different levels of RC and AS on ameliorating acidic soil from a tea garden were investigated. Laboratory incubations showed that combined use of AS and RC was an effective method to reduce soil exchangeable acidity and Al saturation and increase base saturation, but not necessarily for soil pH adjustment. The release of alkalinity from the combined amendments and the mineralization of organic nitrogen increased soil pH initially, but then soil pH decreased due to nitrifications. Various degrees of nitrification were correlated with the interaction of different Ca levels, pH and N contents. When RC was applied at low levels, high Ca levels from AS repressed soil nitrification, resulting in smaller pH fluctuations. In contrast, high AS stimulated soil nitrification, when RC was applied at high levels, and resulted in a large pH decrease. Based on the optimum pH for tea production and quality, high ratios of AS to RC were indicated for soil acidity amelioration, and 8.0 g kg-1 and less than 2.5 g kg-1 were indicated for AS and RC, respectively. Further, field studies are needed to investigate the variables of combined amendments.  相似文献   

9.
Anionic polyacrylamide (PAM) has the potential to reduce soil erosion through soil conditioning. However, a comprehensive study about its effectiveness especially when applied combined with other amendments have rarely been conducted in the tropical highland climatic conditions, such as in Ethiopia. The study assessed the effectiveness of PAM (P = 40 kg ha?1) alone or integrated with other soil amendments such as gypsum (G = 5 t ha?1), lime (L = 4 t ha?1) and biochar (B = 8 t ha?1) on runoff and soil loss at Aba Gerima watershed in the Upper Blue Nile basin, northwest of Ethiopia, where there is high erosion-caused soil degradation. A total of 79 daily runoff and sediment data were collected from eight runoff plots (1.3m × 4m) with three replications planted with teff (Eragrostis tef) crop for two years (2018 & 2019) rainy seasons. Associated changes in soil physicochemical properties and crop growth parameters were investigated. Treatments reduced seasonal runoff by 12–39% and soil loss by 13–53%. The highest reduction in runoff was observed from P + B and PAM treatments while the highest reduction in soil loss was observed from that of P + L and PAM treatments. Integrating PAM with other amendments improved soil structural stability, moisture content, soil pH (P + L) and organic matter (P + B), leading to favorable environment for crop growth (biomass yield) and reduced runoff and soil erosion. Unlike PAM, biochar and lime amendments may need more time after application to be more effective. Hence continuing the field experiment and studying physico-chemical mechanisms for extended period will better elucidate their single or combined effectiveness over time.  相似文献   

10.
Low phosphorus availability in cultivated soils limits sustainable crop production in sub‐Saharan Africa. This study aimed at evaluating the effect of long‐term application of different types of organic amendments on soil P forms, P use efficiency and sorghum yields. A long term experiment established in 1980 at Saria in Burkina Faso, comparing the effects of manure, compost and sorghum straw was used. Manure and compost significantly increased organic P and resin‐P by about 35% and 64%, respectively after 10 and 32 years of sorghum cultivation, and HCl‐P after 32 years of cultivation compared to the control. Manure significantly increased NaHCO3-Pi and NaOH-Pi by 63% and 26%, respectively compared to the control. Sorghum straw had little effect on measured soil P forms. Manure and compost were the best in increasing sorghum grain yield, which effect were strongly correlated to soil pH, carbon and nitrogen. The partial factors productivities of P resulting from the application of studied organic amendments were similar and low, but significantly higher than that of the control treatment. Organic amendments with high P content, maintaining soil carbon and pH could be used to improve soil P availability, sorghum yield and reduce the demand for mineral phosphorus fertilizers.  相似文献   

11.
ABSTRACT

An incubation study was undertaken to examine the periodic release of some macronutrients and micronutrients in a sandy loam treated with different organic amendments (farmyard manure, mushroom compost, poultry manure, vermicompost, biogas slurry, and biochar of Lantana weed) added @ 15 t ha?1 for 120 d through entrapment of released nutrients on ion exchange resins. Among organic amendments, the highest total contents were recorded for Ca, Mg, and S in farmyard manure, for K, Fe, and Mn in mushroom compost, for P, Zn, and Cu in biogas slurry, for B in biochar. The highest average release was recorded for P, Zn, Mn, and B from poultry manure, for Cu from biogas slurry, for Fe from vermicompost, for Ca, Mg, and S from mushroom compost, and for K from farmyard manure. The kinetics of mineralization and release of these nutrients conformed well to the zero-order kinetics and also to a power function equation. The initial release amount and release rate coefficient estimated by the power function equations were correlated significantly to the general properties of organic amendments and also to the type of C species present in organic amendment. Organic amendments having relatively higher content of water soluble C or fulvic or humic acids are likely to release nutrients through an early mineralization/solubilization from soil reserve.  相似文献   

12.
Abstract

Influence of long‐term sodic‐water (SW) irrigation with or without gypsum and organic amendments [green manure (GM), farmyard manure (FYM), and rice straw (RS)] on soil properties and nitrogen (N) mineralization kinetics was studied after 12 years of rice–wheat cropping in a sandy loam soil in northwest India. Long‐term SW irrigation increased soil pH, exchangeable sodium percentage (ESP), and sodium adsorption ratio (SAR) and decreased organic carbon (OC) and total N content. On the other hand, application of gypsum and organic amendments resulted in significant improvement in all these soil properties. Mineralization of soil N ranged from 54 to 111 mg N kg?1 soil in different treatments. Irrigation with SW depressed N mineralization. In SW‐irrigated plots, two flushes of N mineralization were observed; the first during 0 to 7 d and the second after 28 d. Amending SW irrigated plots with GM and FYM enhanced mineralization of soil N. Gypsum application along with SW irrigation reduced cumulative N mineralization at 56 days in RS‐amended plots but increased it under GM‐treated, FYM‐treated, or unamended plots. Nitrogen mineralization potential (No) ranged from 62 to 543 mg N kg?1 soil. In the first‐order zero‐order model (FOZO), the easily decomposable fraction ranged from 5.4 to 42 mg N kg?1 soil. Compared to the first‐order single compartment model, the FOZO model could better explain the variations in N mineralization in different treatments. Variations in No were influenced more by changes in pH, SAR, and ESP induced by long‐term SW irrigations and amendments rather than by soil OC.  相似文献   

13.
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.  相似文献   

14.
ABSTRACT

Damage to soil structures and depletions of soil carbon under paddy cultivation are concerns for the sustenance of food security in Bangladesh. Long-term organic amendment in paddy field plays an important role in improving soil properties and crop productivity, but no such study has yet been conducted under rice-fallow-rice. A field experiment was carried out with or without the addition of cow dung (CD) and poultry manure (PM) as integrated plant nutrient systems (IPNS) to evaluate soil organic carbon (SOC) budget, net ecosystem carbon stock, and aggregate stability. The experiment was established in 2009 and continued until 2016 under the rice-fallow-rice system. Soil bulk density reduced from 1.39 to 1.37 g cm?3 and soil aggregate size increased from 6.78 to 7.05 mm with organic amendments. Both carbon (C) and nitrogen (N) contents increased with the addition of CD and PM, which varied with aggregate size. The highest C (1.6–2.15%) and N (0.11–0.24%) contents were observed in 0.30 mm aggregate than other fractions. Soil organic C contents showed polynomial relationships with aggregate size and organic amendment. The SOC sequestration ranged from 94 to 168 kg ha?1 depending on organic materials used. The C balances were negative for control (?99 to ?201 kg ha?1) and chemical fertilizers alone (?58 to ?91 kg ha?1). In comparison to control treatment, grain yield of rice increased significantly with the addition of organic substances. Balanced application of CD and PM with IPNS-based inorganic fertilizers was the best management option for yield and sustainable soil health.  相似文献   

15.
多孔改良剂对毕节烟区土壤性状及烤烟产质量的影响   总被引：8，自引：0，他引：8  
为研究适合毕节烟区的土壤改良措施,通过大田小区分析比较了不施改良剂(CK)、施用秸秆(T1)、T20改良剂(T2)、70%T20改良剂+30%竹炭(T3)四种处理对植烟土壤性状及烤烟产质的影响。结果表明,与对照相比,不同改良剂可使土壤p H提高0.02~0.23个单位,全氮、全磷、全钾含量分别提高1.21%~7.27%、1.16%~8.14%和0.83%~4.44%;土壤碱解氮、有效磷、速效钾分别提高3.39%~15.2%、10.8%~50.9%及1.78%~37.0%。从生长特性看,T1、T2及T3处理烤烟株高、茎围、有效叶数及叶面积均较CK有所增加。从产质量来看,改良剂处理烟叶产量较CK增产3.6%~8.0%,烟叶产值增加3 030~4 910元hm-2,上等烟叶比例提升3.6%~11.7%;T1、T2处理每千克烟叶均价提高了1.8元及1.0元。所有处理的烤烟烟碱、全氮、还原糖、钾离子、氯离子均处于优质烟叶适宜范围,而施用改良剂的烟叶全氮、还原糖、钾离子含量均高于CK处理,添加土壤改良剂有助于改善烤烟氮碱比、糖碱比、糖氮比,使烤烟内在化学成分渐趋合理。总之,毕节烟区适当添加土壤改良剂能有效改善烟田土壤条件,提升烤烟产量和品质。  相似文献   

16.
通过对滨海盐化潮土小麦—玉米轮作2年田间定位试验,研究不同改良剂施用对土壤团聚体分布、稳定性及土壤团聚体中有机碳含量、各级团聚体有机碳对总有机碳贡献率的影响。试验共设置3个处理:对照(CK)、有机土壤改良剂(OSA)和有机—无机土壤改良剂(CSA),分析土壤团聚体分布、水稳性大团聚体(R_(0.25))、平均重量直径(mean weight diameter,MWD)、几何平均直径(geometric mean diameter,GMD)、分形维数(D)、有机碳储量(soil organic carbon storage,SOCS)和有机碳贡献率(contribution rate of organic carbon)。结果表明,滨海盐化潮土水稳性团聚体组成主要以0.25 mm粒径为主,改良剂施用后土壤R_(0.25)显著提高,其影响主要集中在5 mm和2～5 mm粒径级,OSA处理2个粒级团聚体含量较CK分别显著增加167.38%和59.00%,CSA处理分别显著增加89.17%和100.66%。施用OSA与CSA同时显著提高了土壤团聚体MWD和GMD值,说明2种改良剂的施用均有利于提高大团聚体数量及稳定性。施用改良剂2年处理土壤各粒级团聚体中有机碳含量均有所提高,OSA处理以1～2 mm粒级提高最多,CSA以2～5 mm粒级提高最多,且前者达显著水平。与CK相比,改良剂可促使土壤有机碳向大团聚体富集,显著提高1～2 mm粒级团聚体对土壤总有机碳的贡献率93.62%～109.76%,降低或显著降低1～2 mm粒级团聚体对土壤总有机碳的贡献率20.55%～24.92%。在小麦—玉米轮作模式下,改良剂施用不仅可以显著提高滨海盐化潮土水稳性大团聚体含量和稳定性,还可显著增加水稳性大团聚体有机碳含量与储量,是加强盐碱土壤有机碳库积累的有效措施。  相似文献   

17.
Abstract

Yields were evaluated three years after applied treatments to determine if responses that were not evident during earlier years eventually occurred. Potassium sulfate was applied to established, non‐irrigated, K deficient trees on fine textured soil by banding, placing in augered holes, adding to the backfilled trenches, and by injecting into the soil. Trenches were dug in the fall beside trees to break roots and ammended during backfilling with K2SO4, dolomite lime or combinations of the two. Additional trees received a heavy compost mulch in the early fall. Trenching treatments were generally detrimental. Trenching alone reduced yield and leaf Ca but increased fruit soluble solids content. Trenching plus K2SO4, trenching and lime, all soil amendments, and mushroom compost elevated leaf K from deficient or below normal to the normal range, but decreased leaf Mg. Most K application techniques eventually increased yield, but simple surface applications of K2SO4 in a narrow band were as effective as other more costly procedures. Mulching treatments appear to be as effective as K additions and produce quicker yield responses. Mushroom composts and alfalfa increased leaf N and yield in two years. Mushroom compost doubled yield even three years after a single application.  相似文献   

18.
ABSTRACT

A greenhouse experiment was conducted to evaluate the effects of wheat straw and its biochar on tomato seedling growth and soil physicochemical properties under different moisture levels. Treatments included control (no amendments, CK), three biochar amendments (B1: 1%, B2: 3% and B3: 6% w/w) and three straw amendments (S1: 1%, S2: 3% and S3: 6% w/w), under two moisture levels (M1: 40% water holding capacity (WHC) and M2: 70% WHC). The straw and biochar had contrasting effects on soil physiochemical properties and physiology of tomato seedlings. The B1 treatment significantly increased the soil urease activity (15%) and decreased the activity of dehydrogenase and β glucosidase enzymes (67% and 56%), as compared to the S1 treatment, especially for the high moisture condition. Biochar significantly improved shoot and root dry weights, biomass and altered chlorophyll contents. Plant antioxidants, superoxide dismutase (SOD), Peroxidase (POD) activities and malondialdehyde (MDA) were significantly decreased in biochar treatments, however, an increasing trend was observed for straw treatments. The current findings suggest that application of high amount of biochar (6%) or low amount of straw (1%) would be a reasonable management practice in semi-arid regions to improve soil physiochemical properties and the physiology of tomato seedlings.  相似文献   

19.
Abstract

Considerable within‐field variation in the N content and appearance of sugarbeet (Beta vulgaris L.) leaf canopies is found often at root harvest. Since this heterogeneity can affect subsequent soil N mineralization, a study was initiated to determine if the within‐field variation could be identified and located by aerial photography and a global positioning system (GPS). An aerial color photograph was taken of a commercial sugarbeet field prior to harvest. Three reflectance patterns associated with different degrees of canopy greenness ("green”; [G], “yellow‐green”; [YG] and “yellow”; [Y]) were identified readily. Four areas, each approximately 0.8 ha in size, with these three canopy types were selected. The canopy subsites were located by use of a GPS unit. The G, YG, and Y canopy types contained 277, 138, and 85 kg N ha‐1, respectively, in sugarbeet tops. The corresponding leaf N concentrations were 30.6, 20.1, and 15.8 g kg‐1, respectively. Postharvest soil NO3‐N levels in the upper 120 cm of soil were 57, 14, and 10 kg ha‐1 for the G, YG, and Y canopy sites, respectively. Nitrate‐N in sugarbeet tops returned to the soils was at least partly responsible for the higher soil NO3‐N at the G subsites. In contrast to dry matter yield, recoverable sugar yield was significantly less for roots associated with the G‐canopy type than for roots associated with the YG‐and Y‐canopy sites. Aerial photography and GPS technology can increase precision of soil testing for NO3‐N after a sugarbeet crop, help to identify areas of increased soil N mineralization for a subsequent crop, and decrease subsequent N fertilizer use if a variable rate N‐fertilizer applicator is used.  相似文献   

20.
《Journal of plant nutrition》2013,36(10):2243-2259
ABSTRACT

Compost significantly enhanced strawberry (Fragaria × ananassa Duch.) plant growth and fruit quality when used as a soil supplement. Adding half strength of Peter nutrient solution (50% fertilizer) to a mixture of 50% soil plus 50% compost was very effective in significantly increasing plant dry weight to approximately double that of controls (without compost), fruit yield by more than 70%, and fruit size by 15% compared to controls in the two strawberry cultivars (“Allstar” and “Honeoye”). Compost and fertilizer also significantly enhanced leaf chlorophyll content. Nitrate reductase activity significantly increased in leaves and roots with the greatest increases when using 50% soil plus 50% compost. Strawberry plants grown with compost had significantly higher levels of nitrogen (N) and potassium (K), but lower levels of manganese (Mn), iron (Fe), molybdenum (Mo), and nickel (Ni) in fruit of both “Allstar” and “Honeoye”. Adding compost to the soil mix did not change zinc (Zn) and cadmium (Cd) levels. Use of compost also significantly increased levels of organic acids (malic and citric acid), sugars (fructose, glucose, and total sugars), soluble solids content, and titratable acidity content in both cultivars. The results indicate that the use of compost can reduce the amount of fertilizer required for optimum strawberry plant growth.  相似文献   

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