Soybean （Glycine max （L.）） is one of the most important legume crops being introduced in the CHK （Central Highlands of Kenya） expected to increase yields. However, low levels of soil N （nitrogen） and other pla...Soybean （Glycine max （L.）） is one of the most important legume crops being introduced in the CHK （Central Highlands of Kenya） expected to increase yields. However, low levels of soil N （nitrogen） and other plant nutrients and soil acidity are seen as the major causes impairing goal achievement. To evaluate the influence of manure, lime, P （phosphorus） fertilizer and their combination on N uptake and soybean performance, an experiment was conducted in Embu ATC （Agricultural Training College） comprising 9 treatments, arranged in a Randomized Complete Block Design with 4 replicates in plots of 4 m×4.5 m. The study included manure （0, 5 and 10 t-ha-1）, lime （0 and 2 t.ha-1） and P fertilizer （0, 30 and 60 kg.P.hal）. The treatments significantly influenced N uptake and soybean yields. Both parameters responded well to application of manure both alone or combined to lime and TSP （triple super phosphate）. From these it was concluded that organic and inorganic resources have potential to enhance N uptake and soybean and other crops yields in CHK.展开更多
The behaviour of nanofertilizers(NFs)in plant-soil systems can differ from that of conventional chemical fertilizers due to their peculiar chemical-physical properties.Their effectiveness is still poorly understood.In...The behaviour of nanofertilizers(NFs)in plant-soil systems can differ from that of conventional chemical fertilizers due to their peculiar chemical-physical properties.Their effectiveness is still poorly understood.In this study,we evaluated the P fertilization potential of a novel nanosized FePO4NF(FePNF)in a plant-soil microcosm in a pot experiment.The efficacies of FePNF and a conventional P fertilizer(triple superphosphate,TSP)in sustaining the growth of cucumber plants were evaluated.Plants were grown for 28 d on a P-deficient soil,and determinations were made of plant growth parameters,mineral nutrient concentrations in plant tissues,P availability in soil,activities of soil enzymes involved in C,N,P,and S mineralization,and soil microbial community structure.No significant differences were found in plant dry weight,leaf area,chlorophyll content,or root growth between the FePNF and TSP treatments.Conversely,P availability in soil and P concentration in plant tissues at the end of the plant growth period were significantly higher after TSP fertilization compared to FePNF fertilization,whereas no significant differences were observed for other nutrients.Among the measured soil enzyme activities,there were no significant differences in the activities of soil acid phosphatase,β-glucosidase,and arylsulfatase between the FePNF and TSP treatments,while soil alkaline phosphatase activity was higher in the TSP treatment than in the FePNF treatment and the protease activity was higher in the FePNF treatment than in the TSP treatment.The FePNF and TSP treatments showed significant differences in soil archaeal,bacterial,and fungal community structures,although the microbial community profiles generally clustered closer to each other in the two treatments.We concluded that FePNF can be an efficient alternative to the conventional P fertilizer TSP.展开更多
Corn(Zea mays L.)is a very sensitive crop to phosphorus(P)deficiency during the early development phase,which may be a limiting factor for the sustainable production of this crop in P-deficient tropical soils.However,...Corn(Zea mays L.)is a very sensitive crop to phosphorus(P)deficiency during the early development phase,which may be a limiting factor for the sustainable production of this crop in P-deficient tropical soils.However,scientific evidence indicates that inoculation with phosphate-solubilizing bacteria can improve the development,uptake,and P-use efficiency of corn plants.In the present study,two contrasting corn hybrids were investigated for their responsiveness to multiple inoculations of Bacillus subtilis,B.megaterium,B.velezencis,and Pseudomonas fluorescens and application of phosphate fertilizer rates in the sandy soil of the Brazilian Cerrado.Plants from stable(DKB 360 PRO3)and responsive(DKB 255 PRO3)corn hybrids were inoculated with 0 and 2 mL of inoculant containing multiple phosphate-solubilizing bacteria and fertilized with low(0 mg P·kg^(-1)),medium(40 mg P·kg^(-1))and high(80 mg P·kg^(-1))levels of phosphate fertilizer using triple superphosphate(46% of P_(2)O_(5)).Treatments were distributed in a randomized block design using 2×2×3 factorial scheme,with four replicates.Plants were grown in 8-L pots for 70 days under greenhouse conditions.Morphological characteristics,leaf P concentration,and P use efficiency of corn plants were evaluated.Our results showed that the multiple inoculations of Bacillus subtilis,B.megaterium,B.velezencis,and Pseudomonas fluorescens are a promising sustainable agricultural practice to be recommended for corn cultivation,especially because it improves the development and P use efficiency of plants fertilized with medium P levels,which reduces the costs associated with mineral phosphate fertilization,a non-renewable fertilizer source.In sandy tropical soilwith low P availability,applying intermediate rates of highly soluble phosphate fertilizer,such as triple superphosphate,is sufficient to maximize plant development and the nutritional status of corn crops for sustainable production with low environmental impact.展开更多
In order to develop organic rice and increase paddy soil fertility by cloverorganic rice rotation, the effects of N, P and K fertilizers on growth of clover nitrogen-fixing rhizobia and soil fertility after plantation...In order to develop organic rice and increase paddy soil fertility by cloverorganic rice rotation, the effects of N, P and K fertilizers on growth of clover nitrogen-fixing rhizobia and soil fertility after plantation were investigated, thereby providing certain reference for reasonable cultivation of clover and improvement of soil fertility. A two-year experiment was conducted from 2012 to 2013. The clover was cultivated after rice every year, and different levels of N, P and K fertilizers were applied before winter. In the treatment group, no fertilizer was applied. The effects of different fertilizers and different application amounts on clover yield, nitrogen-fixing rhizobia quantity, nitrogen-fixing rhizobia weight and soil fertility after plantation were analyzed. The results showed that the application of N, P and K fertilizers in the early stage had significantly effect on the growth of clover. When the application amount of N fertilizer was 75 kg/hm^2（N 46%）, the clover yield, nitrogen-fixing rhizobia quantity and nitrogen-fixing rhizobia weight were highest. The soil nitrogen content after plantation increased with the increase of the application amount of N fertilizer, while the P and K content decreased and then increased with the increased application amounts. Soil available P content increased with the increased application amounts of N and P fertilizers, but it did not change significantly with the increased application amount of K fertilizer. Soil available K content increased first and then decreased with the increased application amounts of N and P fertilizers.When the application amounts of N and P fertilizers were 150（N 46%） and 300（P_2O_5 12%） kg/hm^2, soil available K content reached the maximum. Soil organic matter content increased with the increased application amounts of N, P and K fertilizers. Therefore, in the cultivation of clover, appropriate application of N, P and K fertilizers in the early stage can improve clover yield and soil fertility.展开更多
In this paper, the effect of different fertilizer treatments on the main indexes of growth and development and dry matter accumulation of perennial mulberry, which is cut and pruned in summer, were studied with ‘3414...In this paper, the effect of different fertilizer treatments on the main indexes of growth and development and dry matter accumulation of perennial mulberry, which is cut and pruned in summer, were studied with ‘3414’ field experiment design. The results showed that N, P, and K at proper amounts could promote mulberry growth and development, improve its dry matter content, increase its dry matter accumulation. The effects of N, P, K on leaf yield per plant were respectively expressed as follows： N2 N3 N1 N0 , P2 P1 P3 P0 , K2 K1 K3 K0 . It can be concluded that the recommended fertilizer amounts of dry matter accumulations in mulberry leaf were 694.36 kg/hm2 of N, 198.15 kg/hm2 of P, and 274.26 kg/hm2 of K and the dry matter achieved the maximum at 8 045.04 kg/hm2 . The recommended fertilizer amounts of accumulated dry matter in branch were 1 000.05 kg/hm2 of N, 242.04 kg/hm2 of P, and 218.01 kg/hm 2 of K, and the dry matter achieved the maximum at 5 969.05 kg/hm2 . The recommended fertilizer amount in young shoots were 883.76 kg/hm2 of N, 204.48 kg/hm2 of P and 426.59 kg/hm2 of K and dry matter achieved the maximum at 1 410.24 kg/hm2 . This paper could provide reference for the construction of highly-qualified mulberry field in Sichuan hilly area.展开更多
Field experiments were conducted with five rates （0, 75, 150, 225, and 450 kg P205 ha^-1） of seedbed P fertilizer application to investigate the yield of tomato in response to fertilizer P rate on calcareous soils w...Field experiments were conducted with five rates （0, 75, 150, 225, and 450 kg P205 ha^-1） of seedbed P fertilizer application to investigate the yield of tomato in response to fertilizer P rate on calcareous soils with widely different levels of Olsen P （13-142 mg kg^-1） at 15 sites in some suburban counties of Beijing in 1999. Under the condition of no P fertilizer application, tomato yield generally increased with an increase in soil test P levels, and the agronomic level for soil testing P measured with Olsen method was 50 or 82 mg kg^-1 soil to achieve 85% or 95% of maximum tomato yield, respectively. With regard to marketable yield, in the fields where Olsen-P levels were 〈 50 mg kg^-1, noticeable responses to applied P were observed. On the basis of a linear plateau regression, the optimum seedbed P application rate in the P-insufflcient fields was 125 kg P205 ha^-1 or about 1.5-2 times the P removal from harvested tomato plants. In contrast, in fields with moderate （50 〈 Olsen P 〈 90 mg kg^-1） or high （Olsen P 〉 90 mg kg^-1） available P, there was no marked effect on tomato fruit yield. Field survey data indicated that in most fields with conventional P management, a P surplus typically occurred. Thus, once the soil test P level reached the optimum for crop yield, it was recommended that P fertilizer application be restricted or eliminated to minimize negative environmental effects.展开更多
Vesicular-arbuscular mycorrhizal (VAM) fungi have been credited with improving the groWth and mineral nutrition of many host plants but these effects are moderated by soil factors and nutrient balance. The combined ef...Vesicular-arbuscular mycorrhizal (VAM) fungi have been credited with improving the groWth and mineral nutrition of many host plants but these effects are moderated by soil factors and nutrient balance. The combined effects of VAM, Zn and P application on the growth and translocation of nutrients in wheat were investigated using a calcareous soil marginal in P and Zn concentrations. Wheat was grown in a growth chamber under various combinations of VAM, P and Zn with measurements done at heading stage and maturity.Vegetative dry matter accumulation was increased by P application and reduced by VAM treatments. Both P and VAM increased grain yield. Zinc concentration and uptake were generally reduced by P addition and VAM infection. There were no antagonistic effects of Zn on P acquisition in the plant. The role of VAM in enhancing the translocation of Zn and P from root to grain would be beneficial to seed setting and yield.展开更多
The long-term productivity of a soil is greatly influenced by cation exchange capacity（CEC）.Moreover,interactions between dominant base cations and other nutrients are important for the health and stability of grass...The long-term productivity of a soil is greatly influenced by cation exchange capacity（CEC）.Moreover,interactions between dominant base cations and other nutrients are important for the health and stability of grassland ecosystems.Soil exchangeable base cations and cation ratios were examined in a 11-year experiment with sheep manure application rates 0–1,500 g/（m2？a） in a semi-arid steppe in Inner Mongolia of China,aiming to clarify the relationships of base cations with soil p H,buffer capacity and fertility.Results showed that CEC and contents of exchangeable calcium（Ca2＋）,magnesium（Mg2＋）,potassium（K＋） and sodium（Na＋） were significantly increased,and Ca2＋ saturation tended to decrease,while K＋ saturation tended to increase with the increases of sheep manure application rates.The Ca2＋/Mg2＋ and Ca2＋/K＋ ratios decreased,while Mg2＋,K＋ and Na＋ saturations increased with increasing manure application rates.Both base cations and CEC were significantly and positively correlated with soil organic carbon（SOC） and soil p H.The increases of SOC and soil p H would be the dominant factors that contribute to the increase of cations in soil.On a comparison with the initial soil p H before the experiment,we deduced that sheep manure application could partly buffer soil p H decrease potentially induced by atmospheric deposition of nitrogen and sulfur.Our results indicate that sheep manure application is beneficial to the maintenance of base cations and the buffering of soil acidification,and therefore can improve soil fertility in the semi-arid steppes of northeastern China.展开更多
Phosphorus（P） is an important macronutrient for plant but can also cause potential environmental risk. In this paper, we studied the long-term fertilizer experiment（started 1980） to assess the soil P dynamic, bala...Phosphorus（P） is an important macronutrient for plant but can also cause potential environmental risk. In this paper, we studied the long-term fertilizer experiment（started 1980） to assess the soil P dynamic, balance, critical P value and the crop yield response in Taihu Lake region, China. To avoid the effect of nitrogen（N） and potassium（K）, only the following treatments were chosen for subsequent discussion, including： C0（control treatment without any fertilizer or organic manure）, CNK treatment（mineral N and K only）, CNPK（balanced fertilization with mineral N, P and K）, MNK（integrated organic manure and mineral N and K）, and MNPK（organic manure plus balanced fertilization）. The results revealed that the response of wheat yield was more sensitive than rice, and no significant differences of crop yield had been detected among MNK, CNPK and MNPK until 2013. Dynamic and balance of soil total P（TP） and Olsen-P showed soil TP pool was enlarged significantly over consistent fertilization. However, the diminishing marginal utility of soil Olsen-P was also found, indicating that high-level P application in the present condition could not increase soil Olsen-P contents anymore. Linear-linear and Mitscherlich models were used to estimate the critical value of Olsen-P for crops. The average critical P value for rice and wheat was 3.40 and 4.08 mg kg^（–1）, respectively. The smaller critical P value than in uplands indicated a stronger ability of P supply for crops in this paddy soil. We concluded that no more mineral P should be applied in rice-wheat system in Taihu Lake region if soil Olsen-P is higher than the critical P value. The agricultural technique and management referring to activate the plant-available P pool are also considerable, such as integrated use of low-P organic manure with mineral N and K.展开更多
The application of mineral and organic phosphorus fertilizers to arable land has greatly increased crop yield to meet the world food demand.On the other hand,impurities in these fertilizers,such as heavy metals,are be...The application of mineral and organic phosphorus fertilizers to arable land has greatly increased crop yield to meet the world food demand.On the other hand,impurities in these fertilizers,such as heavy metals,are being added to agricultural soils,resulting both from the raw materials themselves and the processes used to obtain the final product.Cadmium,a non-essential and toxic heavy metal,has been found in relatively high amounts in common P fertilizers obtained from sediments.This metal poses a high risk for soil fertility,crop cultivation,and plants in general.Furthermore,human health might be compromised by the cadmium concentrations in agricultural and livestock products,due to the bioaccumulation effect in the food web.The accumulation in the different matrixes is the result of the high mobility and flexible availability of this harmful metal.This review summarizes risks to human health,the factors influencing cadmium movement in soils and crop uptake,as well as common plant responses to its toxicity.In addition,it summarizes cadmium balances in soils,trends,long-term experiments,and further studies.Cadmium inputs and outputs in arable soil,together with their calculated concentrations,are compared between two different regions:the European countries(in particular Germany)and China.The comparison appears useful because of the different proportions in the inputs and outputs of cadmium,and the diverse geographical,environmental and social factors.Moreover,these variables and their influences on cadmium contamination improve the understanding of the pollution from phosphate fertilizers and will help to establish future mitigation policies.展开更多
Nitrogen(N),phosphate(P),and potassium(K)are the three most important nutrients applied into agricultural soils,but the impacts of their single or combined application on soil fungal community structure and stability ...Nitrogen(N),phosphate(P),and potassium(K)are the three most important nutrients applied into agricultural soils,but the impacts of their single or combined application on soil fungal community structure and stability are still open questions.Using qPCR and Illumina Miseq sequencing,the variation of soil fungal communities in response to long-term addition of N,P,or K fertilization alone and their combinations in a Mollisol field was investigated in this study.In addition,the fungal community resistance indices and network structure were studied.Results showed that N fertilizations(N,NK,NP and NPK treatments)rather than P,K fertilizations(P,K and PK treatments)significantly increased fungal abundance,but decreased fungal diversity and shifted fungal community structures when compared to non-fertilization(NoF).Additionally,N fertilization treatments presented lower resistance of fungal communities to environment disturbances than those of P,K fertilization treatments.More numbers and higher abundances of changed fungal taxa at the genus and OTU levels were induced by N fertilizations rather than by addition of P,K fertilizers.In addition,N fertilizations induced a more changeable fungal network and complex pathogenic subnetwork with many positive interactions among responding plant pathogens(RP,the changeable plant pathogens induced by fertilizers addition compared to NoF)when compared to P,K fertilizations.These RP directly and negatively influenced fungal community resistance examined by structural equation modeling(SEM),which were indirectly detrimental to soybean yields.Our findings revealed that addition of N fertilizers significantly disturbed fungal communities and promoted pathogenic interactions,and provided insights into the optimization of fertilization strategies toward agricultural sustainability.展开更多
The forms of phosphorus(P)in animal manure and peat are different from synthetic P fertilizers and will affect soil P fractions when they are used as P amendments.Effects of chicken manure(CMB)and peat(PB)derived bioc...The forms of phosphorus(P)in animal manure and peat are different from synthetic P fertilizers and will affect soil P fractions when they are used as P amendments.Effects of chicken manure(CMB)and peat(PB)derived biochars(CMB and PB)alone or in combination with P fertilizer(KH_(2)PO_(4))and rock phosphate(RP)on plant/soil health and soil P fractions in an acidic ultisol were examined with greenhouse pot experiments.The total P rate was constant at 120 mg kg^(−1) in all treatments.Soil P fractions,P uptake,and maize growth were determined after 56 days.Application of CMB combined with P fertilizer or alone significantly increased soil pH,water extractable and relatively labile P,dry matter yield of maize,chlorophyll contents in maize leaves,while decreasing the Fe and Al binding P.Moreover,sole application of CMB and PB showed greater effects than application of P fertilizer alone regarding plant growth and P fractionation.Integration of syn-thetic inorganic P sources with CMB or sole application of CMB is more beneficial than application of inorganic P sources to improve plant growth and P availability.展开更多
文摘Soybean （Glycine max （L.）） is one of the most important legume crops being introduced in the CHK （Central Highlands of Kenya） expected to increase yields. However, low levels of soil N （nitrogen） and other plant nutrients and soil acidity are seen as the major causes impairing goal achievement. To evaluate the influence of manure, lime, P （phosphorus） fertilizer and their combination on N uptake and soybean performance, an experiment was conducted in Embu ATC （Agricultural Training College） comprising 9 treatments, arranged in a Randomized Complete Block Design with 4 replicates in plots of 4 m×4.5 m. The study included manure （0, 5 and 10 t-ha-1）, lime （0 and 2 t.ha-1） and P fertilizer （0, 30 and 60 kg.P.hal）. The treatments significantly influenced N uptake and soybean yields. Both parameters responded well to application of manure both alone or combined to lime and TSP （triple super phosphate）. From these it was concluded that organic and inorganic resources have potential to enhance N uptake and soybean and other crops yields in CHK.
基金supported by the Joint Project 2016 and the Joint Project 2019,developed by the University of Verona and Fabbrica Cooperativa Perfosfati Cerea,Italy。
文摘The behaviour of nanofertilizers(NFs)in plant-soil systems can differ from that of conventional chemical fertilizers due to their peculiar chemical-physical properties.Their effectiveness is still poorly understood.In this study,we evaluated the P fertilization potential of a novel nanosized FePO4NF(FePNF)in a plant-soil microcosm in a pot experiment.The efficacies of FePNF and a conventional P fertilizer(triple superphosphate,TSP)in sustaining the growth of cucumber plants were evaluated.Plants were grown for 28 d on a P-deficient soil,and determinations were made of plant growth parameters,mineral nutrient concentrations in plant tissues,P availability in soil,activities of soil enzymes involved in C,N,P,and S mineralization,and soil microbial community structure.No significant differences were found in plant dry weight,leaf area,chlorophyll content,or root growth between the FePNF and TSP treatments.Conversely,P availability in soil and P concentration in plant tissues at the end of the plant growth period were significantly higher after TSP fertilization compared to FePNF fertilization,whereas no significant differences were observed for other nutrients.Among the measured soil enzyme activities,there were no significant differences in the activities of soil acid phosphatase,β-glucosidase,and arylsulfatase between the FePNF and TSP treatments,while soil alkaline phosphatase activity was higher in the TSP treatment than in the FePNF treatment and the protease activity was higher in the FePNF treatment than in the TSP treatment.The FePNF and TSP treatments showed significant differences in soil archaeal,bacterial,and fungal community structures,although the microbial community profiles generally clustered closer to each other in the two treatments.We concluded that FePNF can be an efficient alternative to the conventional P fertilizer TSP.
基金financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nível Superior-Brasil(CAPES)-Finance Code 001financial resources from the Fundacao de Apoio ao Desenvolvimento do Ensino,Ciencia e Tecnologia do Estado de Mato Grosso do Sul—FUNDECT(Termo de Outorga:133/2023/SIAFEM:33108).
文摘Corn(Zea mays L.)is a very sensitive crop to phosphorus(P)deficiency during the early development phase,which may be a limiting factor for the sustainable production of this crop in P-deficient tropical soils.However,scientific evidence indicates that inoculation with phosphate-solubilizing bacteria can improve the development,uptake,and P-use efficiency of corn plants.In the present study,two contrasting corn hybrids were investigated for their responsiveness to multiple inoculations of Bacillus subtilis,B.megaterium,B.velezencis,and Pseudomonas fluorescens and application of phosphate fertilizer rates in the sandy soil of the Brazilian Cerrado.Plants from stable(DKB 360 PRO3)and responsive(DKB 255 PRO3)corn hybrids were inoculated with 0 and 2 mL of inoculant containing multiple phosphate-solubilizing bacteria and fertilized with low(0 mg P·kg^(-1)),medium(40 mg P·kg^(-1))and high(80 mg P·kg^(-1))levels of phosphate fertilizer using triple superphosphate(46% of P_(2)O_(5)).Treatments were distributed in a randomized block design using 2×2×3 factorial scheme,with four replicates.Plants were grown in 8-L pots for 70 days under greenhouse conditions.Morphological characteristics,leaf P concentration,and P use efficiency of corn plants were evaluated.Our results showed that the multiple inoculations of Bacillus subtilis,B.megaterium,B.velezencis,and Pseudomonas fluorescens are a promising sustainable agricultural practice to be recommended for corn cultivation,especially because it improves the development and P use efficiency of plants fertilized with medium P levels,which reduces the costs associated with mineral phosphate fertilization,a non-renewable fertilizer source.In sandy tropical soilwith low P availability,applying intermediate rates of highly soluble phosphate fertilizer,such as triple superphosphate,is sufficient to maximize plant development and the nutritional status of corn crops for sustainable production with low environmental impact.
基金Science&Technology Specific Project for Enriching People and Strengthening County Economy(BN2015221)~~
文摘In order to develop organic rice and increase paddy soil fertility by cloverorganic rice rotation, the effects of N, P and K fertilizers on growth of clover nitrogen-fixing rhizobia and soil fertility after plantation were investigated, thereby providing certain reference for reasonable cultivation of clover and improvement of soil fertility. A two-year experiment was conducted from 2012 to 2013. The clover was cultivated after rice every year, and different levels of N, P and K fertilizers were applied before winter. In the treatment group, no fertilizer was applied. The effects of different fertilizers and different application amounts on clover yield, nitrogen-fixing rhizobia quantity, nitrogen-fixing rhizobia weight and soil fertility after plantation were analyzed. The results showed that the application of N, P and K fertilizers in the early stage had significantly effect on the growth of clover. When the application amount of N fertilizer was 75 kg/hm^2（N 46%）, the clover yield, nitrogen-fixing rhizobia quantity and nitrogen-fixing rhizobia weight were highest. The soil nitrogen content after plantation increased with the increase of the application amount of N fertilizer, while the P and K content decreased and then increased with the increased application amounts. Soil available P content increased with the increased application amounts of N and P fertilizers, but it did not change significantly with the increased application amount of K fertilizer. Soil available K content increased first and then decreased with the increased application amounts of N and P fertilizers.When the application amounts of N and P fertilizers were 150（N 46%） and 300（P_2O_5 12%） kg/hm^2, soil available K content reached the maximum. Soil organic matter content increased with the increased application amounts of N, P and K fertilizers. Therefore, in the cultivation of clover, appropriate application of N, P and K fertilizers in the early stage can improve clover yield and soil fertility.
基金Supported by Science&Technology Innovation of Sichuan Characteristic AgricultureProvincial Breeding Key Project of the 12th Five Year Plan (No.2011yzgg-13-02-01)+2 种基金Sichuan Academy of Agricultural Sciences (2011LWJJ-008)Seed Industry Innovation and Transformation Project (2011JYGC10-027-02)Modern Agricultural Technology System Project (No.CARS-22)~~
文摘In this paper, the effect of different fertilizer treatments on the main indexes of growth and development and dry matter accumulation of perennial mulberry, which is cut and pruned in summer, were studied with ‘3414’ field experiment design. The results showed that N, P, and K at proper amounts could promote mulberry growth and development, improve its dry matter content, increase its dry matter accumulation. The effects of N, P, K on leaf yield per plant were respectively expressed as follows： N2 N3 N1 N0 , P2 P1 P3 P0 , K2 K1 K3 K0 . It can be concluded that the recommended fertilizer amounts of dry matter accumulations in mulberry leaf were 694.36 kg/hm2 of N, 198.15 kg/hm2 of P, and 274.26 kg/hm2 of K and the dry matter achieved the maximum at 8 045.04 kg/hm2 . The recommended fertilizer amounts of accumulated dry matter in branch were 1 000.05 kg/hm2 of N, 242.04 kg/hm2 of P, and 218.01 kg/hm 2 of K, and the dry matter achieved the maximum at 5 969.05 kg/hm2 . The recommended fertilizer amount in young shoots were 883.76 kg/hm2 of N, 204.48 kg/hm2 of P and 426.59 kg/hm2 of K and dry matter achieved the maximum at 1 410.24 kg/hm2 . This paper could provide reference for the construction of highly-qualified mulberry field in Sichuan hilly area.
基金Project supported by the National Natural Science Foundation of China (No. 30230250) the Ministry of Agriculture, China (No. 2003-Z53).
文摘Field experiments were conducted with five rates （0, 75, 150, 225, and 450 kg P205 ha^-1） of seedbed P fertilizer application to investigate the yield of tomato in response to fertilizer P rate on calcareous soils with widely different levels of Olsen P （13-142 mg kg^-1） at 15 sites in some suburban counties of Beijing in 1999. Under the condition of no P fertilizer application, tomato yield generally increased with an increase in soil test P levels, and the agronomic level for soil testing P measured with Olsen method was 50 or 82 mg kg^-1 soil to achieve 85% or 95% of maximum tomato yield, respectively. With regard to marketable yield, in the fields where Olsen-P levels were 〈 50 mg kg^-1, noticeable responses to applied P were observed. On the basis of a linear plateau regression, the optimum seedbed P application rate in the P-insufflcient fields was 125 kg P205 ha^-1 or about 1.5-2 times the P removal from harvested tomato plants. In contrast, in fields with moderate （50 〈 Olsen P 〈 90 mg kg^-1） or high （Olsen P 〉 90 mg kg^-1） available P, there was no marked effect on tomato fruit yield. Field survey data indicated that in most fields with conventional P management, a P surplus typically occurred. Thus, once the soil test P level reached the optimum for crop yield, it was recommended that P fertilizer application be restricted or eliminated to minimize negative environmental effects.
文摘Vesicular-arbuscular mycorrhizal (VAM) fungi have been credited with improving the groWth and mineral nutrition of many host plants but these effects are moderated by soil factors and nutrient balance. The combined effects of VAM, Zn and P application on the growth and translocation of nutrients in wheat were investigated using a calcareous soil marginal in P and Zn concentrations. Wheat was grown in a growth chamber under various combinations of VAM, P and Zn with measurements done at heading stage and maturity.Vegetative dry matter accumulation was increased by P application and reduced by VAM treatments. Both P and VAM increased grain yield. Zinc concentration and uptake were generally reduced by P addition and VAM infection. There were no antagonistic effects of Zn on P acquisition in the plant. The role of VAM in enhancing the translocation of Zn and P from root to grain would be beneficial to seed setting and yield.
基金funded by the National Natural Science Foundation of China (41371251,31370009)the National Basic Research Program of China (2011CB403204)
文摘The long-term productivity of a soil is greatly influenced by cation exchange capacity（CEC）.Moreover,interactions between dominant base cations and other nutrients are important for the health and stability of grassland ecosystems.Soil exchangeable base cations and cation ratios were examined in a 11-year experiment with sheep manure application rates 0–1,500 g/（m2？a） in a semi-arid steppe in Inner Mongolia of China,aiming to clarify the relationships of base cations with soil p H,buffer capacity and fertility.Results showed that CEC and contents of exchangeable calcium（Ca2＋）,magnesium（Mg2＋）,potassium（K＋） and sodium（Na＋） were significantly increased,and Ca2＋ saturation tended to decrease,while K＋ saturation tended to increase with the increases of sheep manure application rates.The Ca2＋/Mg2＋ and Ca2＋/K＋ ratios decreased,while Mg2＋,K＋ and Na＋ saturations increased with increasing manure application rates.Both base cations and CEC were significantly and positively correlated with soil organic carbon（SOC） and soil p H.The increases of SOC and soil p H would be the dominant factors that contribute to the increase of cations in soil.On a comparison with the initial soil p H before the experiment,we deduced that sheep manure application could partly buffer soil p H decrease potentially induced by atmospheric deposition of nitrogen and sulfur.Our results indicate that sheep manure application is beneficial to the maintenance of base cations and the buffering of soil acidification,and therefore can improve soil fertility in the semi-arid steppes of northeastern China.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest of China(201203030)the Science and Technology Support Program of Jiangsu,China(BE2013334)the Agricultural Science&Technology Innovation Foundation of Jiangsu Province,China(CX(14)5085)
文摘Phosphorus（P） is an important macronutrient for plant but can also cause potential environmental risk. In this paper, we studied the long-term fertilizer experiment（started 1980） to assess the soil P dynamic, balance, critical P value and the crop yield response in Taihu Lake region, China. To avoid the effect of nitrogen（N） and potassium（K）, only the following treatments were chosen for subsequent discussion, including： C0（control treatment without any fertilizer or organic manure）, CNK treatment（mineral N and K only）, CNPK（balanced fertilization with mineral N, P and K）, MNK（integrated organic manure and mineral N and K）, and MNPK（organic manure plus balanced fertilization）. The results revealed that the response of wheat yield was more sensitive than rice, and no significant differences of crop yield had been detected among MNK, CNPK and MNPK until 2013. Dynamic and balance of soil total P（TP） and Olsen-P showed soil TP pool was enlarged significantly over consistent fertilization. However, the diminishing marginal utility of soil Olsen-P was also found, indicating that high-level P application in the present condition could not increase soil Olsen-P contents anymore. Linear-linear and Mitscherlich models were used to estimate the critical value of Olsen-P for crops. The average critical P value for rice and wheat was 3.40 and 4.08 mg kg^（–1）, respectively. The smaller critical P value than in uplands indicated a stronger ability of P supply for crops in this paddy soil. We concluded that no more mineral P should be applied in rice-wheat system in Taihu Lake region if soil Olsen-P is higher than the critical P value. The agricultural technique and management referring to activate the plant-available P pool are also considerable, such as integrated use of low-P organic manure with mineral N and K.
基金carried out as part of the project “Adaptation of Maize-based Food-feed-energy Systems to Limited Phosphate Resources” from the German-Chinese International Research Training Group 2366the support for this project provided by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)–328017493/GRK 2366Ten-Thousand Talent Program of China (Xuejun Liu)
文摘The application of mineral and organic phosphorus fertilizers to arable land has greatly increased crop yield to meet the world food demand.On the other hand,impurities in these fertilizers,such as heavy metals,are being added to agricultural soils,resulting both from the raw materials themselves and the processes used to obtain the final product.Cadmium,a non-essential and toxic heavy metal,has been found in relatively high amounts in common P fertilizers obtained from sediments.This metal poses a high risk for soil fertility,crop cultivation,and plants in general.Furthermore,human health might be compromised by the cadmium concentrations in agricultural and livestock products,due to the bioaccumulation effect in the food web.The accumulation in the different matrixes is the result of the high mobility and flexible availability of this harmful metal.This review summarizes risks to human health,the factors influencing cadmium movement in soils and crop uptake,as well as common plant responses to its toxicity.In addition,it summarizes cadmium balances in soils,trends,long-term experiments,and further studies.Cadmium inputs and outputs in arable soil,together with their calculated concentrations,are compared between two different regions:the European countries(in particular Germany)and China.The comparison appears useful because of the different proportions in the inputs and outputs of cadmium,and the diverse geographical,environmental and social factors.Moreover,these variables and their influences on cadmium contamination improve the understanding of the pollution from phosphate fertilizers and will help to establish future mitigation policies.
基金This study was financially supported from the Strategic Priority Research Program of Chinese Academy of Sciences(XDA28020201)the National Natural Science Foundation of China(41907035)the Natural Science Foundation of Heilongjiang Province(ZD2018009).
文摘Nitrogen(N),phosphate(P),and potassium(K)are the three most important nutrients applied into agricultural soils,but the impacts of their single or combined application on soil fungal community structure and stability are still open questions.Using qPCR and Illumina Miseq sequencing,the variation of soil fungal communities in response to long-term addition of N,P,or K fertilization alone and their combinations in a Mollisol field was investigated in this study.In addition,the fungal community resistance indices and network structure were studied.Results showed that N fertilizations(N,NK,NP and NPK treatments)rather than P,K fertilizations(P,K and PK treatments)significantly increased fungal abundance,but decreased fungal diversity and shifted fungal community structures when compared to non-fertilization(NoF).Additionally,N fertilization treatments presented lower resistance of fungal communities to environment disturbances than those of P,K fertilization treatments.More numbers and higher abundances of changed fungal taxa at the genus and OTU levels were induced by N fertilizations rather than by addition of P,K fertilizers.In addition,N fertilizations induced a more changeable fungal network and complex pathogenic subnetwork with many positive interactions among responding plant pathogens(RP,the changeable plant pathogens induced by fertilizers addition compared to NoF)when compared to P,K fertilizations.These RP directly and negatively influenced fungal community resistance examined by structural equation modeling(SEM),which were indirectly detrimental to soybean yields.Our findings revealed that addition of N fertilizers significantly disturbed fungal communities and promoted pathogenic interactions,and provided insights into the optimization of fertilization strategies toward agricultural sustainability.
基金This study was supported by the National Key Research and Development of China(No.2016YFD0200302).
文摘The forms of phosphorus(P)in animal manure and peat are different from synthetic P fertilizers and will affect soil P fractions when they are used as P amendments.Effects of chicken manure(CMB)and peat(PB)derived biochars(CMB and PB)alone or in combination with P fertilizer(KH_(2)PO_(4))and rock phosphate(RP)on plant/soil health and soil P fractions in an acidic ultisol were examined with greenhouse pot experiments.The total P rate was constant at 120 mg kg^(−1) in all treatments.Soil P fractions,P uptake,and maize growth were determined after 56 days.Application of CMB combined with P fertilizer or alone significantly increased soil pH,water extractable and relatively labile P,dry matter yield of maize,chlorophyll contents in maize leaves,while decreasing the Fe and Al binding P.Moreover,sole application of CMB and PB showed greater effects than application of P fertilizer alone regarding plant growth and P fractionation.Integration of syn-thetic inorganic P sources with CMB or sole application of CMB is more beneficial than application of inorganic P sources to improve plant growth and P availability.
