[Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers（SCRF）on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei ho...[Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers（SCRF）on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei hot pepper（Capsicum frutescens L.）as the experimental material,we studied the fertilization effect and environment-protecting effect of SCRF.[Result] The result showed that SCRF could improve the agronomic characteristics of hot pepper.Compared to singly applied common fertilizers,SCRF increased economic yield by 20.90% and economic benefit by 13 234.35 Yuan/hm2,and the ratio of output to input was improved by 47.93%.In comparison with common straight fertilizers at same NPK proportion and rate,SCRF increased economic yield by 5.26% and economic benefit by 5 554.80 Yuan/hm2,and the ratio of output to input was improved by 9.91%.Under the reduced use of SCRF by 20%,SCRF increased economic yield by 12.38% and economic benefit by 9595.20 Yuan/hm2 compared with singly applied common fertilizers,and the ratio of output to input was improved by 65.95%.SCRF improved nitrogen,phosphorus and potassium use efficiencies by 12.42-17.53,3.35-5.24 and 5.37-14.02 percents respectively.[Conclusion] As the result of much reduced N and P application rates,SCRF would significantly economize fertilizer resources and minimize the pollution caused by the loss of fertilizer nutrients,which is of practical importance for environment protection.展开更多
[Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation（Dianthus caryophyl...[Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation（Dianthus caryophyllus）as research object,the application effect and environmental protection effect of slow release fertilizer on carnation were discussed through field plot test.[Result] The main agronomic characters of carnation improved after the application of slow release fertilizer;compared with Conv-F treatment,the yield of carnation with slow release fertilizer increased by 18.67%-20.83%,and its economic benefit increased by 105 500 yuan/hm2,while the ratio of output to input improved by 74.29%;under the same NPK ratio and nutrient amount,the yield,economic benefit and ratio of output to input of carnation after the application of slow release fertilizer increased by 2.11%,14 800 yuan and 16.2%,respectively;besides,the application of slow release fertilizer improved the nutrient use efficiency of carnation,and N,P and K nutrient use efficiency in Opt-F-0.7% treatment increased by 13.88%,8.57% and 30.14% compared with Conv-F treatment.[Conclusion] Slow release fertilizer could not only reduce the waste of fertilizer resources and improve fertilizer use efficiency but also decrease the pollution caused by nutrient loss,which had important practical significance for protecting ecological environment and promoting the sustainable development of agriculture.展开更多
The primary challenge of mineland revegetation is the establishment of species able to cope with low availability of nutrients,especially in steep slopes such as of mine pits.We evaluated plant growth response and nut...The primary challenge of mineland revegetation is the establishment of species able to cope with low availability of nutrients,especially in steep slopes such as of mine pits.We evaluated plant growth response and nutrient use efficiency(NUE)of two promising native Fabaceae species(Dioclea apurensis—liana from metalliferous savannas;Bauhinia longipedicellata—tree from Amazon rainforest)from the Caraja´s Mineral Province,eastern Amazon-Brazil.Plants were grown separately in 2-kg pots filled with mining waste.Substrates were fertilized with nitrogen,phosphorus,potassium(NPK),lime,and micronutrients.The results showed increments on growth of both species when nutrients were applied to the mining waste.D.apurensis showed increases in leaf area,plant height,stem diameter,and shoot dry mass production when NPK or NPK?micronutrients were applied,while B.longipedicelata was responsive to application of NPK?lime or NPK?lime?micronutrients.Further,D.apurensis showed higher NUE than B.longipedicelata,especially at the lowest doses of N,P and K.These findings may indicate a substantial advantage of D.apurensis for mineland revegetation,as this species may require lower nutrient inputs,being,therefore,a more sustainable way to revegetate degraded areas.展开更多
The development of green super rice varieties with improved nutrient use efficiency(NuUE)is a vital target area to increase yield and make it more stable under rainfed conditions.In the present study, we followed an e...The development of green super rice varieties with improved nutrient use efficiency(NuUE)is a vital target area to increase yield and make it more stable under rainfed conditions.In the present study, we followed an early backcross(BC) breeding approach by using a highyielding and widely adapted Xian variety, Weed Tolerant Rice 1(WTR-1), as a recipient and a Geng variety, Hao-An-Nong(HAN), as a donor.Starting from the BC1F2 generation, the BC population went through one generation of selection under irrigated, low-input, and rainfed conditions, followed by four consecutive generations of screening and selection for high grain yield(GY) under six different nutrient conditions(NPK, 75 N,-N,-P,-NP, and-NPK), leading to the development of 230 BC1F6 introgression lines(ILs).These 230 ILs were evaluated under the same six nutrient conditions for 13 agro-morphological and grain yield component traits in comparison to four checks and parents.Significant trait variations were observed between the treatments and ILs.Positive correlations were identified for GY with biomass, panicle length, flag-leaf area, flag-leaf width, filled grain number per panicle,1000-grain weight, and tiller number under-N,-P,-NP, and-NPK conditions.Out of 230 ILs,12 were identified as promising under two or more nutrient deficiency conditions.The results demonstrated an efficient inter-subspecific BC breeding procedure with a first round of selection under rainfed-drought conditions, followed by four generations of progeny testing for yield performance under six nutrient conditions.The promising ILs can be useful resources for molecular genetic dissection and understanding the physiological mechanisms of NuUE.展开更多
Agricultural land use and management practices may affect soil properties,which play a critical role in sustaining crop production.Since the late 1970s,several new agricultural land use types had been introduced in th...Agricultural land use and management practices may affect soil properties,which play a critical role in sustaining crop production.Since the late 1970s,several new agricultural land use types had been introduced in the rural areas of China.The purpose of this study is to evaluate the effect of these land use changes on the soil properties,nu-trient absorption rate,and nutrient use economic efficiency ratio in an agricultural area of Beijing.Specifically,the cropland,the orchard and the vegetable field were examined.Results of this study suggest that land use and farming management practices significantly affect the content of soil organic carbon (SOC),total nitrogen (TN),total phos-phorus (TP),and available phosphorus in the surface layer of 0-25 cm (p<0.05) in the Yanqing Basin,northwestern Beijing.Soil nutrients in each agricultural land use type decrease rapidly with the increasing soil depth.Orchard and vegetable field tend to have higher soil nutrients than the cropland does.However,the soil nutrient-absorption rate (NAR) of the orchard and vegetable field is lower than that of the cropland,even though orchard and vegetable field may provide much higher economic benefit.While increasing SOC,TN,and TP in the orchard and vegetable field by intensive farming may be a valuable option to improve soil quality,potential increase in the risk of nutrient loss,or agricultural non-point source pollution can be a tradeoff if the intensive practices are not managed appropriately.展开更多
The development of wheat cultivars with improved nitrogen(N),phosphorus(P),and potassium(K)use efficiency is essential for sustainable agriculture.Genetic dissection and identification of causative genes underlying nu...The development of wheat cultivars with improved nitrogen(N),phosphorus(P),and potassium(K)use efficiency is essential for sustainable agriculture.Genetic dissection and identification of causative genes underlying nutrient use efficiency represent a key strategy toward this goal.We conducted an extensive genome-wide association study(GWAS)using a panel of 431 wheat cultivars,identifying 1,659 significant single-nucleotide polymorphisms(SNPs)(LOD>5)through genotyping-by-sequencing.This analysis revealed 534 quantitative trait loci(QTLs)associated with 12 nutrient use efficiency traits across five distinct environments,among which 14 QTLs were consistently detected in at least three environments.Notably,meta-QTL analysis,showed that QTL80(72.12–74.24 Mb,chr2A),QTL387(32.88–33.56 Mb,chr6A),and QTL500(535.53–540.80 Mb,chr7B)exhibit clear co-localization with MQTL-2A-2,MQTL-6A-1,and MQTL-7B-2,respectively.This overlap highlights their robustness across diverse environmental conditions.Within these regions,critical candidate genes-including members of the bZIP transcription factor family and a potassium transporter gene-were identified in relation to nutrient use efficiency.Furthermore,a novel locus,QTL234,was discovered,harboring key candidate genes such as dof zinc finger protein,Ankyrin repeat family protein,and cytochrome P450.To validate the SNP within QTL234 associated with nitrogen harvest index(NHI),we developed a dCAPS marker for AX-109095537.These findings demonstrate the effectiveness of high-resolution SNP-based GWAS in rapidly pinpointing promising candidate genes.They also establish a foundation for large-scale QTL fine mapping,candidate gene validation,and the development of functional markers essential for enhancing nutrient use efficiency in wheat breeding programs.展开更多
Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit th...Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit the stress signals within cells as well as between cells and tissues,and make appropriate adjustments in their growth and development in order to survive and reproduce.In recent years,significant progress has been made on many fronts of the stress signaling research,particularly in understanding the downstream signaling events that culminate at the activation of stress-and nutrient limitation-responsive genes,cellular ion homeostasis,and growth adjustment.However,the revelation of the early events of stress signaling,particularly the identification of primary stress sensors,still lags behind.In this review,we summarize recent work on the genetic and molecular mechanisms of plant abiotic stress and nutrient limitation sensing and signaling and discuss new directions for future studies.展开更多
Potassium is one of the most important nutrients for rice production in many areas of Asia, especially in southeast China where potassium deficiency in soil is a widespread problem. Field experiments were conducted fo...Potassium is one of the most important nutrients for rice production in many areas of Asia, especially in southeast China where potassium deficiency in soil is a widespread problem. Field experiments were conducted for four consecutive years in Jinhua City, Zhejiang Province, to determine utilization of nutrients (N, P and K) by inbred and hybrid rice and rice grain yields as affected by application of potassium fertilizer under irrigated conditions. Grain yield and nutrient harvest index showed a significant response to the NPK treatment as compared to the NP treatment. This suggested that potassium improved transfer of nitrogen and phosphorus from stems and leaves to panicles in rice plants. N and P use efficiencies of rice were not strongly responsive to potassium, but K use efficiency decreased significantly despite the fact that the amount of total K uptake increased. A significant difference between varieties was also observed with respect to nutrient uptake and use efficiency. Hybrid rice exhibited physiological advantage in N and P uptake and use efficiency over inbred rice. Analysis of annual dynamic change of exchangeable K and non-exchangeable K in the test soil indicated that non-exchangeable K was an important K source for rice. Potassium application caused an annual decrease in the concentration of available K in the soil tested, whereas an increase was observed in non-exchangeable K. It could be concluded that K fertilizer application at the rate of 100 kg ha-1 per season was not high enough to match K output, and efficient K management for rice must be based on the K input/output balance.展开更多
China is in a dominant position in apple production globally with both the largest apple growing area and the largest export of fresh apple fruits. However, the annual productivity of China＇s apple is significantly l...China is in a dominant position in apple production globally with both the largest apple growing area and the largest export of fresh apple fruits. However, the annual productivity of China＇s apple is significantly lower than that of other dominant apple producing countries. In addition, apple production is based on excessive application of chemical fertilizers and the nutrient use efficiency （especially nitrogen） is therefore low and the nutrient emissions to the environment are high. Apple production in China is considerably contributes to farmers＇ incomes and is important as export product. There is an urgent need to enhance apple productivity and improve nutrient use efficiencies in intensive apple production systems in the country. These can be attained by improved understanding of production potential, yield gaps, nutrient use and best management in apple orchards. To the end, priorities in research on apple production systems and required political support are described which may lead to more sustainable and environmental-friendly intensification of apple production in China.展开更多
The success of the Green Revolution largely relies on fertilizers, and a new Green Revolution is very much needed to use fertilizers more economically and efficiently, as well as with more environmental responsibility...The success of the Green Revolution largely relies on fertilizers, and a new Green Revolution is very much needed to use fertilizers more economically and efficiently, as well as with more environmental responsibility. The use efficiency of nitrogen, phosphorus, and potassium is controlled by complex gene networks that co-ordinate uptake, re-distribution, assimilation, and storage of these nutrients. Great progress has been made in breeding nutrient-efficient crops by molecularly engineering root traits desirable for efficient acquisition of nutrients from soil, transporters for uptake, redistribution and homeostasis of nutrients, and enzymes for efficient assimilation. Regulatory and transcription factors modulating these processes are also valuable in breeding crops with improved nutrient use efficiency and yield performance.展开更多
Optimal planting density and proper fertilization method are important factors to improve maize yield and nutrient utilization. A two-year(2016 and 2017) field experiment was conducted with three plant densities(6.0, ...Optimal planting density and proper fertilization method are important factors to improve maize yield and nutrient utilization. A two-year(2016 and 2017) field experiment was conducted with three plant densities(6.0, 7.5 and 9.0 plants m^-2) and three fertilization modes(no fertilizer, 0 F;one-off application of slow-released fertilizer, SF;twice application of conventional fertilizer, CF). Results indicated that the grain yields and N, P and K use efficiencies under SF with the optimal planting density(7.5 plants m^-2) were the highest among all the treatments in 2016 and 2017. Compared with CF, SF could increase post-silking dry matter accumulation and promote N, P and K uptake at pre-and post-silking stages;this treatment increased grain N, P and K concentrations and resulted in high N, P and K use efficiencies. Nutrient(N, P and K) absorption efficiencies and partial productivity, and nutrient(N and P) recovery efficiency in SF treatment were significantly higher than those in CF treatments under the planting density of 7.5 plants m^-2. Under both SF and CF conditions, the grain yield, total N accumulation and nutrient use efficiencies initially increased, peaked at planting density of 7.5 plants m^-2, and then decreased with increasing plant density. Based on the yield and nutrient use efficiency in two years, plant density of 7.5 plants m^-2 with SF can improve both the grain yield and N, P and K use efficiency of spring maize in Jiangsu Province, China.展开更多
Development and use of controlled release fertilizer (CRF) in southern China, potential advantages of CRF in increasing rice yield and nutrient use efficiency were introduced, as well as its role of minimizing rice fi...Development and use of controlled release fertilizer (CRF) in southern China, potential advantages of CRF in increasing rice yield and nutrient use efficiency were introduced, as well as its role of minimizing rice field’s environmental contamination was discussed. Meanwhile, some suggestions were proposed.展开更多
Biochar is considered a potential technology to enhance chemical fertilizer use efficiency through intensification of the interactions between nutrients and the functional groups on biochar surfaces.However,little is ...Biochar is considered a potential technology to enhance chemical fertilizer use efficiency through intensification of the interactions between nutrients and the functional groups on biochar surfaces.However,little is known about how the application of activated biochars mixed with urea influences nitrogen(N)mineralization and crop performance in paddy fields.Here,a sawdust-derived fresh biochar(FBC)(ca.400℃)was activated chemically with 15%hydrogen peroxide and biologically with a nutrient solution mixed with a soil inoculum to obtain a chemically activated biochar(CBC)and a biologically activated biochar(BBC),respectively.The chemical and surface properties of FBC,CBC,and BBC were evaluated using spectroscopic methods,i.e.,Fourier transform infrared spectroscopy and 13C nuclear magnetic resonance,and potentiometric charge determination.The N retention capacity of biochars and their interaction with urea hydrolysis were examined in a laboratory incubation experiment.Additionally,a field experiment was carried out in a paddy field with the biochars unmixed or mixed with urea at a 1:1 ratio.Our results showed that negative surface functional groups and negative charges were increased on both activated biochars,especially CBC.Both activated biochars contributed to a significant reduction in urea-biochar suspension pH and increased N retention in the incubation experiment.Despite the enhanced surface properties of the activated biochars,no similar increases in rice biomass and grain yield were observed for these biochars in the field experiment.However,rice biomass,grain yield,apparent N use efficiency,and agronomic N use efficiency were significantly higher with the application of the three biochars compared to no-biochar application.Altogether,the results indicate that the application of urea mixed with biochar could enhance crop performance,especially in the case of activated biochar,which would enhance N retention in the soil,reducing N loss.展开更多
Leaf litterfall,litter decomposition and nutrient return through litterfall of three dominant species,i.e.Quercus serrata,Schima wallichi and Lithocarpus dealbata were studied in different months throughout the year t...Leaf litterfall,litter decomposition and nutrient return through litterfall of three dominant species,i.e.Quercus serrata,Schima wallichi and Lithocarpus dealbata were studied in different months throughout the year to assess the input and release of nutrient in the forest soil of a sub-tropical mixed oak forest of Manipur,northeastern India.Oaks in northeastern region of India are economically important species for the production of Tasar silk.The monthly litterfall ranged from 25.6 g·m^-2（July） to 198.0 g·m^-2（February） and annual litterfall was 1093.8g·m^-2 in the forest site.At initial month（on November 3）,the concentrations of N and C were the highest in L.dealbata,followed by Q.serrata and lowest in S.wallichi,whereas lignin and cellulose concentrations at initial month were the highest in S.wallichi,followed by Q.serrata and L.dealbata.L.dealbata（k=0.54） exhibited a high rate of litter decomposition,coinciding with high concentrations of N and C and low cellulose in the litter at initial month.However,low rate of litter decomposition in S.wallichi（k=0.33） coincided with low value of N and C and highest value of lignin and cellulose at initial month.The remaining biomass in different months was positively correlated with the lignin,C,C/N ratio and cellulose,but it negatively correlated with nitrogen concentrations at initial month.The rate of litter decomposition was the highest in rainy summer months,owing to congenial environmental conditions and lowest rate of litter decomposition in cool and dry winter months.展开更多
We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf li...We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha-1 a-1 for S. robusta to 11.03 ± 3.72 t ha-1 a-1 for T. grandis and the decay constant （k） of decomposed leaf litter was distinctly higher for T. grandis （2.70 ± 0.50 a-1） compared to S. robusta （2.41 ±0.30 a-1）. Biomass loss was positively correlated with the initial litter C, WSC, C/N and ash content in S. robusta and N, P and K concentration for T. grandis. Biomass was negatively correlated with lignin and L/N ratio for S. robusta and L, WSC, L/N and C/N ratio for T. grandis （P 〈 0.01）. Nutrient use efficiency （NUE） and nutrient accumulation index （NAI） of S. robusta was higher than for T. grandis. The retranslocation of bioelements from senescent leaves ranked as P 〉 N 〉 K. Annual N, P and K input to soil through litterfall differed significantly between the two species in the following order： N〉K^P. S. robusta was superior in terms of K and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release （K 〉 P 〉 N） during decomposition of their leaf litter.Nutrients of N, K and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity.展开更多
This study was executed to offer the basis for optimized profit from fertilizer use for sorghum yield and to determine robust crop nutrient response function and economic rate for the production of sorghum at Miesso C...This study was executed to offer the basis for optimized profit from fertilizer use for sorghum yield and to determine robust crop nutrient response function and economic rate for the production of sorghum at Miesso Central Rift Valley of Ethiopia. Trails were conducted at six experimental sites, sorghum yield response to N and P fertilizers application and economically optimum rates of nitrogen (EONR) and phosphorus (EOPR) were evaluated on a vertisols within the semi-arid Miesso districts west Hararge zone of Oromia region. The nutrient rates in 2014 cropping season four levels of Nitrogen (N) alone, these levels with 20 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> Phosphorus (P) and without N, 69 kg<span style="white-space:nowrap;">·</span>ha<sup><span style="white-space:nowrap;">−</span>1</sup> N with three levels of P treatments including the zero control were evaluated. In 2015, cropping season similar rates of N alone, the same rate N with 20 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> P, 92 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> N with three rates of P including the zero control were evaluated. The treatments were arranged in a randomized complete block with three replications in factorial design. Nutrient responses of sorghum were determined using asymptotic quadratic plateau functions. The significantly highest nitrogen rate was 46 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> alone in 2014 season, which gave grain yield of 2.56 Mg<span style="white-space:nowrap;">·ha<sup>−1</sup></span><sup> </sup>with a maximum yield advantage of 43%. P rates in both seasons and combined (sites + seasons) were not significantly influenced sorghum yield. Nitrogen agronomic and partial factor productivity peaked at 23 kg N <span style="white-space:nowrap;">ha<sup>−1</sup></span> but declined with increasing N rate. The EONR combined (sites + seasons) were 37, 45, 52 and 60 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span><sup> </sup>and for the profit to cost ratio (PCR) were 2.43, 3.65, 4.86 and 5.79 at difference cost to grain price ratios (CP) = 3.6, 2.3, 1.6 and 1.2 respectively at Miesso Ethiopia. Nitrogen application had economically profitable than P. The study concluded that the application of N at 37 or 60 kg N <span style="white-space:nowrap;">ha<sup>−1</sup></span> to sorghum production could be economically profitable for those economically constrained farmers or economically not constrained farmers. Validation should be farther conducted on farmers’ fields for refining the results obtained.展开更多
Maize （Zea mays L.） is an important food crop in Niger, but low and irregular rainfall combined with sandy soils having low fertility level limit productivity. A two-year study was conducted at Institut National de ...Maize （Zea mays L.） is an important food crop in Niger, but low and irregular rainfall combined with sandy soils having low fertility level limit productivity. A two-year study was conducted at Institut National de Recherche Agronomique du Niger （INRAN） stations in Tarna/Maradi and Bengou/Gaya in 2014 and 2015 in order to evaluate maize agronomic and economic fertilizer use efficiency. The experimental design was a randomised complete block design （RCBD） with three replications. Results indicate higher effect of fertilizer in 2015 compared to 2014. At low N rates 20 kg N/ha and 40 kg N/ha, application of 20 kg P/ha increased maize grain yield across locations and years. The highest agronomic efficiency of N （AEN） was recorded with 60 kg N/ha in 2015 at Bengou and Tarna with 9.65 kg and 14.05 kg grain yield per kg of applied N, respectively. At Tarna, the low N rates of 20 kg N/ha and 40 kg N/ha recorded important AEN of more than 12 kg yield increases per kg of applied N. The highest rainfall use efficiency （RUE） of 6.13 kg/year/mm was obtained with application of 80 kg/ha N, 0 kg/ha P and 40 kg/ha N, 20 kg/ha P in 2015 at Tarna. Without P, the highest value cost ratio （VCR） value of 4.31 was recorded at Tarna in 2015 with 60 kg/ha N, and the lowest value of 0.08 at Bengou in 2014 with 20 kg/ha N. Based on VCR and RUE derived from this study, the optimal fertilizer recommendation for maize in the semi-arid conditions of Niger could be 40 kg/ha N, 20 kg/ha P and 0 kg/ha K.展开更多
Excessive fertilizer application is common in the management of winter wheat (Triticum aestivum L.) in northwest China. However, this practice does not necessarily guarantee higher wheat yield and also causes a waste ...Excessive fertilizer application is common in the management of winter wheat (Triticum aestivum L.) in northwest China. However, this practice does not necessarily guarantee higher wheat yield and also causes a waste of resources and environmental pollution. The nitrogen (N), phosphorus (P), and potassium (K) fertilizer application rates need to be optimized to reduce the nitrate residue in the soil while maintaining a high wheat yield. Field experiments were conducted in three consecutive growth seasons (2018-2021) on winter wheat in Northern Xinjiang of China with four reduced fertilization (N-P_(2)O_(5)- K_(2)O) rates (FS1: 166-80-30 kg/hm^(2), FS2: 0-80-30 kg/hm^(2), FS3: 166-0-30 kg/hm^(2), FS4: 166-80-0 kg/hm^(2)) and the local fertilization rate (CK: 240-105-38). The soil nutrients, nutrient uptake content of organ, dry matter accumulation, yield, and fertilization use efficiency were investigated. The results showed increasing NH_(4)^(+)-N concentrations in the soil over the three growing seasons, while NO_(3)^(-)-N concentrations decreased in the later experimental years. High soil NH_(4)^(+)-N concentration and low soil NH_(4)^(+)-N residues were observed in FS3. When the control fertilization (CK) was applied, the grains had a higher proportion of N and P, while the N content in grains was relatively low at the high fertilization rate. When the fertilizer supply was insufficient (FS2, FS3, and FS4), the proportion of vegetative organs to the total biomass was relatively low. Lower fertilization rates resulted in higher N, P, and K use efficiencies in 2019-2020 and 2020-2021, in comparison to those at higher rates, while FS2 exhibited the highest fertilizer use efficiency. When fertilization (CK) was sufficient, the dry matter accumulation decreased by 3.33%- 17.08%, and the harvest index increased by 0.87%-47.40%. FS1 had the highest spike number, which significantly increased by 17.98%, 17.80%, and 9.64% compared with CK during 2018-2019, 2019-2020, and 2020-2021, respectively. In conclusion, a reduction in fertilizer application compared with CK could provide excellent production results. The optimal drip fertigation approach for winter wheat production in the arid regions of northwest China was determined to be the N-P_(2)O_(5)-K_(2)O application rate of 166-80-30 kg/hm^(2) when comprehensively considering the winter wheat yield, soil NH_(4)^(+)-N, and NH_(4)^(+)-N, N use efficiency, P use efficiency, and K use efficiency. This research can provide a scientific basis for the responses of winter wheat production to nutrient uptake of drip-irrigated winter wheat in arid and semi-arid regions.展开更多
Point placement of urea is an efficient technology to improve urea use efficiency in transplanted rice(Oryza sativa L.), but it is largely unknown how nutrient composition in the point placement and the distance from ...Point placement of urea is an efficient technology to improve urea use efficiency in transplanted rice(Oryza sativa L.), but it is largely unknown how nutrient composition in the point placement and the distance from placement site to the plant influence rice root distribution and growth, nutrient uptake, and rice grain yield. A controlled greenhouse experiment was conducted using both N-and P-deficient soil with point placement of N only or N and P together(N + P) at a distance close to or far from the plant,in comparison to an N-spilt application and a no-N control. Both nutrient composition and distance significantly affected rice root growth. Compared with the N point placement, the N + P point placement led to smaller root length and mass densities, higher specific root length(SRL) around the placement site, smaller root system, higher straw mass and grain yield, and higher N and P uptake. The difference between the N + P and N point placements was greater when close to the plant than when far from the plant. It is suggested that higher SRL around the placement site is essential for improving nutrient uptake and rice grain yield, and simultaneous point placement of N and P has a synergistic effect on rice growth.展开更多
Background Enzymatic stoichiometry reflects microbial relative resource limitations by linking microbial nutritional demands with soil nutrient availability,yet how plant invasion-induced changes in vegetation,soil pr...Background Enzymatic stoichiometry reflects microbial relative resource limitations by linking microbial nutritional demands with soil nutrient availability,yet how plant invasion-induced changes in vegetation,soil properties,and microbial communities modulate these limitations and metabolic efficiency remains undetermined.Here,we employed enzymatic stoichiometry and vector modeling to assess microbial relative resource limitations in invasive Spartina alterniflora salt marsh in comparison to those in bare flat and in native Suaeda salsa and Phragmites australis salt marshes,and systematically linked these limitations to microbial carbon(C)and nitrogen(N)use efficiencies(CUE and NUE,respectively)across coastal wetland ecosystems of eastern China.Results Our analyses showed predominant phosphorus(P)limitation of soil microbial metabolism in bare flat and native S.salsa and P.australis salt marshes,contrasting with dual C-P co-limitation observed in invasive S.alterniflora salt marsh.S.alterniflora invasion intensified microbial P limitation compared with bare flat,while simultaneously inducing the most pronounced C limitation among all plant communities.The microbial C limitation induced by S.alterniflora invasion drove reductions in microbial CUE,whereas microbial NUE increased,establishing an antagonistic relationship between these metabolic efficiencies.Microbial resource constraints and nutrient use efficiencies(CUE/NUE)in soils were coordinately controlled by plant traits,soil properties,and microbial attributes.Partial least squares path modeling analysis identified soil organic C(SOC)chemical fractions(e.g.,aromatic C,alkyl C,dissolved organic C)as predominant positive drivers of microbial C limitation and NUE,while simultaneously suppressing microbial CUE.Simultaneously,plant traits were identified as the foremost contributor to microbial P limitation,followed by microbial attributes as the second-most influential positive factor.Conclusions This study revealed that S.alterniflora invasion fundamentally shifted microbial nutrient limitation from predominant P limitation in bare flat and native salt marshes to dual C-P co-limitation,while simultaneously inducing the strongest microbial C limitation among all communities.This invasion-induced microbial C limitation drove a reduction in microbial CUE but an enhancement of NUE.SOC accumulation increased with decreasing microbial CUE following S.alterniflora invasion,a tradeoff potentially linked to divergent nutrient limitations across ecosystems.This study provided empirical evidence for microbially-mediated soil C sequestration mechanisms underlying plant invasion-induced ecosystem transformations.展开更多
基金Supported by Special Fund for Agro-scientific Research in the Public Interest from Ministry of Agriculture(200903025-05)Fund from Kunming Municipal Science and Technology Committee(08S010201)~~
文摘[Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers（SCRF）on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei hot pepper（Capsicum frutescens L.）as the experimental material,we studied the fertilization effect and environment-protecting effect of SCRF.[Result] The result showed that SCRF could improve the agronomic characteristics of hot pepper.Compared to singly applied common fertilizers,SCRF increased economic yield by 20.90% and economic benefit by 13 234.35 Yuan/hm2,and the ratio of output to input was improved by 47.93%.In comparison with common straight fertilizers at same NPK proportion and rate,SCRF increased economic yield by 5.26% and economic benefit by 5 554.80 Yuan/hm2,and the ratio of output to input was improved by 9.91%.Under the reduced use of SCRF by 20%,SCRF increased economic yield by 12.38% and economic benefit by 9595.20 Yuan/hm2 compared with singly applied common fertilizers,and the ratio of output to input was improved by 65.95%.SCRF improved nitrogen,phosphorus and potassium use efficiencies by 12.42-17.53,3.35-5.24 and 5.37-14.02 percents respectively.[Conclusion] As the result of much reduced N and P application rates,SCRF would significantly economize fertilizer resources and minimize the pollution caused by the loss of fertilizer nutrients,which is of practical importance for environment protection.
基金Supported by National Key Technology R&D Program(2006BAD05B06-04)Kunming Science and Technology Program(08S010201)~~
文摘[Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation（Dianthus caryophyllus）as research object,the application effect and environmental protection effect of slow release fertilizer on carnation were discussed through field plot test.[Result] The main agronomic characters of carnation improved after the application of slow release fertilizer;compared with Conv-F treatment,the yield of carnation with slow release fertilizer increased by 18.67%-20.83%,and its economic benefit increased by 105 500 yuan/hm2,while the ratio of output to input improved by 74.29%;under the same NPK ratio and nutrient amount,the yield,economic benefit and ratio of output to input of carnation after the application of slow release fertilizer increased by 2.11%,14 800 yuan and 16.2%,respectively;besides,the application of slow release fertilizer improved the nutrient use efficiency of carnation,and N,P and K nutrient use efficiency in Opt-F-0.7% treatment increased by 13.88%,8.57% and 30.14% compared with Conv-F treatment.[Conclusion] Slow release fertilizer could not only reduce the waste of fertilizer resources and improve fertilizer use efficiency but also decrease the pollution caused by nutrient loss,which had important practical significance for protecting ecological environment and promoting the sustainable development of agriculture.
文摘The primary challenge of mineland revegetation is the establishment of species able to cope with low availability of nutrients,especially in steep slopes such as of mine pits.We evaluated plant growth response and nutrient use efficiency(NUE)of two promising native Fabaceae species(Dioclea apurensis—liana from metalliferous savannas;Bauhinia longipedicellata—tree from Amazon rainforest)from the Caraja´s Mineral Province,eastern Amazon-Brazil.Plants were grown separately in 2-kg pots filled with mining waste.Substrates were fertilized with nitrogen,phosphorus,potassium(NPK),lime,and micronutrients.The results showed increments on growth of both species when nutrients were applied to the mining waste.D.apurensis showed increases in leaf area,plant height,stem diameter,and shoot dry mass production when NPK or NPK?micronutrients were applied,while B.longipedicelata was responsive to application of NPK?lime or NPK?lime?micronutrients.Further,D.apurensis showed higher NUE than B.longipedicelata,especially at the lowest doses of N,P and K.These findings may indicate a substantial advantage of D.apurensis for mineland revegetation,as this species may require lower nutrient inputs,being,therefore,a more sustainable way to revegetate degraded areas.
基金the Bill & Melinda Gates Foundation (BMGF) for providing a research grant to Z.L.for the Green Super Rice project under ID OPP1130530the Department of Agriculture of the Philippines for providing funds to J.A.under the Next-Gen project.
文摘The development of green super rice varieties with improved nutrient use efficiency(NuUE)is a vital target area to increase yield and make it more stable under rainfed conditions.In the present study, we followed an early backcross(BC) breeding approach by using a highyielding and widely adapted Xian variety, Weed Tolerant Rice 1(WTR-1), as a recipient and a Geng variety, Hao-An-Nong(HAN), as a donor.Starting from the BC1F2 generation, the BC population went through one generation of selection under irrigated, low-input, and rainfed conditions, followed by four consecutive generations of screening and selection for high grain yield(GY) under six different nutrient conditions(NPK, 75 N,-N,-P,-NP, and-NPK), leading to the development of 230 BC1F6 introgression lines(ILs).These 230 ILs were evaluated under the same six nutrient conditions for 13 agro-morphological and grain yield component traits in comparison to four checks and parents.Significant trait variations were observed between the treatments and ILs.Positive correlations were identified for GY with biomass, panicle length, flag-leaf area, flag-leaf width, filled grain number per panicle,1000-grain weight, and tiller number under-N,-P,-NP, and-NPK conditions.Out of 230 ILs,12 were identified as promising under two or more nutrient deficiency conditions.The results demonstrated an efficient inter-subspecific BC breeding procedure with a first round of selection under rainfed-drought conditions, followed by four generations of progeny testing for yield performance under six nutrient conditions.The promising ILs can be useful resources for molecular genetic dissection and understanding the physiological mechanisms of NuUE.
基金Under the auspices of Key Direction in Knowledge Innovation Programs of Chinese Academy of Sciences (No. KZCX2-YW-421)National Natural Science Foundation of China (No.40925003)
文摘Agricultural land use and management practices may affect soil properties,which play a critical role in sustaining crop production.Since the late 1970s,several new agricultural land use types had been introduced in the rural areas of China.The purpose of this study is to evaluate the effect of these land use changes on the soil properties,nu-trient absorption rate,and nutrient use economic efficiency ratio in an agricultural area of Beijing.Specifically,the cropland,the orchard and the vegetable field were examined.Results of this study suggest that land use and farming management practices significantly affect the content of soil organic carbon (SOC),total nitrogen (TN),total phos-phorus (TP),and available phosphorus in the surface layer of 0-25 cm (p<0.05) in the Yanqing Basin,northwestern Beijing.Soil nutrients in each agricultural land use type decrease rapidly with the increasing soil depth.Orchard and vegetable field tend to have higher soil nutrients than the cropland does.However,the soil nutrient-absorption rate (NAR) of the orchard and vegetable field is lower than that of the cropland,even though orchard and vegetable field may provide much higher economic benefit.While increasing SOC,TN,and TP in the orchard and vegetable field by intensive farming may be a valuable option to improve soil quality,potential increase in the risk of nutrient loss,or agricultural non-point source pollution can be a tradeoff if the intensive practices are not managed appropriately.
基金funded by the National Key R&D Program of China(2021YFD1900700)。
文摘The development of wheat cultivars with improved nitrogen(N),phosphorus(P),and potassium(K)use efficiency is essential for sustainable agriculture.Genetic dissection and identification of causative genes underlying nutrient use efficiency represent a key strategy toward this goal.We conducted an extensive genome-wide association study(GWAS)using a panel of 431 wheat cultivars,identifying 1,659 significant single-nucleotide polymorphisms(SNPs)(LOD>5)through genotyping-by-sequencing.This analysis revealed 534 quantitative trait loci(QTLs)associated with 12 nutrient use efficiency traits across five distinct environments,among which 14 QTLs were consistently detected in at least three environments.Notably,meta-QTL analysis,showed that QTL80(72.12–74.24 Mb,chr2A),QTL387(32.88–33.56 Mb,chr6A),and QTL500(535.53–540.80 Mb,chr7B)exhibit clear co-localization with MQTL-2A-2,MQTL-6A-1,and MQTL-7B-2,respectively.This overlap highlights their robustness across diverse environmental conditions.Within these regions,critical candidate genes-including members of the bZIP transcription factor family and a potassium transporter gene-were identified in relation to nutrient use efficiency.Furthermore,a novel locus,QTL234,was discovered,harboring key candidate genes such as dof zinc finger protein,Ankyrin repeat family protein,and cytochrome P450.To validate the SNP within QTL234 associated with nitrogen harvest index(NHI),we developed a dCAPS marker for AX-109095537.These findings demonstrate the effectiveness of high-resolution SNP-based GWAS in rapidly pinpointing promising candidate genes.They also establish a foundation for large-scale QTL fine mapping,candidate gene validation,and the development of functional markers essential for enhancing nutrient use efficiency in wheat breeding programs.
文摘Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit the stress signals within cells as well as between cells and tissues,and make appropriate adjustments in their growth and development in order to survive and reproduce.In recent years,significant progress has been made on many fronts of the stress signaling research,particularly in understanding the downstream signaling events that culminate at the activation of stress-and nutrient limitation-responsive genes,cellular ion homeostasis,and growth adjustment.However,the revelation of the early events of stress signaling,particularly the identification of primary stress sensors,still lags behind.In this review,we summarize recent work on the genetic and molecular mechanisms of plant abiotic stress and nutrient limitation sensing and signaling and discuss new directions for future studies.
基金Project supported by the International Fertilizer Industry Association (IFI), France the Potash & Phos-phate Institute (PPI), USA and Canadathe International Potassium Institute (IPI), Switzerland.
文摘Potassium is one of the most important nutrients for rice production in many areas of Asia, especially in southeast China where potassium deficiency in soil is a widespread problem. Field experiments were conducted for four consecutive years in Jinhua City, Zhejiang Province, to determine utilization of nutrients (N, P and K) by inbred and hybrid rice and rice grain yields as affected by application of potassium fertilizer under irrigated conditions. Grain yield and nutrient harvest index showed a significant response to the NPK treatment as compared to the NP treatment. This suggested that potassium improved transfer of nitrogen and phosphorus from stems and leaves to panicles in rice plants. N and P use efficiencies of rice were not strongly responsive to potassium, but K use efficiency decreased significantly despite the fact that the amount of total K uptake increased. A significant difference between varieties was also observed with respect to nutrient uptake and use efficiency. Hybrid rice exhibited physiological advantage in N and P uptake and use efficiency over inbred rice. Analysis of annual dynamic change of exchangeable K and non-exchangeable K in the test soil indicated that non-exchangeable K was an important K source for rice. Potassium application caused an annual decrease in the concentration of available K in the soil tested, whereas an increase was observed in non-exchangeable K. It could be concluded that K fertilizer application at the rate of 100 kg ha-1 per season was not high enough to match K output, and efficient K management for rice must be based on the K input/output balance.
基金the project "Cash Crops Research Network of China" of the Center for Resources, Environment and Food Security, China Agricultural UniversityProfessor Oene Oenema from Alterra Wageningnen University, the Netherlands, for his financial support of the research
文摘China is in a dominant position in apple production globally with both the largest apple growing area and the largest export of fresh apple fruits. However, the annual productivity of China＇s apple is significantly lower than that of other dominant apple producing countries. In addition, apple production is based on excessive application of chemical fertilizers and the nutrient use efficiency （especially nitrogen） is therefore low and the nutrient emissions to the environment are high. Apple production in China is considerably contributes to farmers＇ incomes and is important as export product. There is an urgent need to enhance apple productivity and improve nutrient use efficiencies in intensive apple production systems in the country. These can be attained by improved understanding of production potential, yield gaps, nutrient use and best management in apple orchards. To the end, priorities in research on apple production systems and required political support are described which may lead to more sustainable and environmental-friendly intensification of apple production in China.
基金supported by the National Key Research and Development Program of China (2016YFD0100706)the National Transgenic Key Project from the Ministry of Agriculture of China (2016ZX08002-005)
文摘The success of the Green Revolution largely relies on fertilizers, and a new Green Revolution is very much needed to use fertilizers more economically and efficiently, as well as with more environmental responsibility. The use efficiency of nitrogen, phosphorus, and potassium is controlled by complex gene networks that co-ordinate uptake, re-distribution, assimilation, and storage of these nutrients. Great progress has been made in breeding nutrient-efficient crops by molecularly engineering root traits desirable for efficient acquisition of nutrients from soil, transporters for uptake, redistribution and homeostasis of nutrients, and enzymes for efficient assimilation. Regulatory and transcription factors modulating these processes are also valuable in breeding crops with improved nutrient use efficiency and yield performance.
基金the financial support of the National Key Research and Development Program of China (2016YFD0300109 and 2018YFD0200703)the National Natural Science Foundation of China (31771709)+2 种基金the Jiangsu Agricultural Industry Technology System of China (JATS[2019]458)the High-end Talent Support Program of Yangzhou University, Chinathe Priority Academic Program Development of Jiangsu Higher Education Institutions, China。
文摘Optimal planting density and proper fertilization method are important factors to improve maize yield and nutrient utilization. A two-year(2016 and 2017) field experiment was conducted with three plant densities(6.0, 7.5 and 9.0 plants m^-2) and three fertilization modes(no fertilizer, 0 F;one-off application of slow-released fertilizer, SF;twice application of conventional fertilizer, CF). Results indicated that the grain yields and N, P and K use efficiencies under SF with the optimal planting density(7.5 plants m^-2) were the highest among all the treatments in 2016 and 2017. Compared with CF, SF could increase post-silking dry matter accumulation and promote N, P and K uptake at pre-and post-silking stages;this treatment increased grain N, P and K concentrations and resulted in high N, P and K use efficiencies. Nutrient(N, P and K) absorption efficiencies and partial productivity, and nutrient(N and P) recovery efficiency in SF treatment were significantly higher than those in CF treatments under the planting density of 7.5 plants m^-2. Under both SF and CF conditions, the grain yield, total N accumulation and nutrient use efficiencies initially increased, peaked at planting density of 7.5 plants m^-2, and then decreased with increasing plant density. Based on the yield and nutrient use efficiency in two years, plant density of 7.5 plants m^-2 with SF can improve both the grain yield and N, P and K use efficiency of spring maize in Jiangsu Province, China.
基金This study was supported by National Natural Science Foundation of China (30270770) Foundation for Achievement Transfer (02EFN214301156) and PPI/PPIC-China Cooperation Project (HN-13).
文摘Development and use of controlled release fertilizer (CRF) in southern China, potential advantages of CRF in increasing rice yield and nutrient use efficiency were introduced, as well as its role of minimizing rice field’s environmental contamination was discussed. Meanwhile, some suggestions were proposed.
基金grateful to the Ministry of Education,Bangladesh for funding the current work with a project(No.LS2018770)the financial support for chemical analysis provided by Spanish Ministry of Science,Innovation and Universities,Spain and the European Regional Development Fund from the European Union(EU FEDER)(No.RTI2018-099417-B-I00)thankful for receiving a fund from the Kubota Consultancy,The Netherlands(No.3710473400-2).
文摘Biochar is considered a potential technology to enhance chemical fertilizer use efficiency through intensification of the interactions between nutrients and the functional groups on biochar surfaces.However,little is known about how the application of activated biochars mixed with urea influences nitrogen(N)mineralization and crop performance in paddy fields.Here,a sawdust-derived fresh biochar(FBC)(ca.400℃)was activated chemically with 15%hydrogen peroxide and biologically with a nutrient solution mixed with a soil inoculum to obtain a chemically activated biochar(CBC)and a biologically activated biochar(BBC),respectively.The chemical and surface properties of FBC,CBC,and BBC were evaluated using spectroscopic methods,i.e.,Fourier transform infrared spectroscopy and 13C nuclear magnetic resonance,and potentiometric charge determination.The N retention capacity of biochars and their interaction with urea hydrolysis were examined in a laboratory incubation experiment.Additionally,a field experiment was carried out in a paddy field with the biochars unmixed or mixed with urea at a 1:1 ratio.Our results showed that negative surface functional groups and negative charges were increased on both activated biochars,especially CBC.Both activated biochars contributed to a significant reduction in urea-biochar suspension pH and increased N retention in the incubation experiment.Despite the enhanced surface properties of the activated biochars,no similar increases in rice biomass and grain yield were observed for these biochars in the field experiment.However,rice biomass,grain yield,apparent N use efficiency,and agronomic N use efficiency were significantly higher with the application of the three biochars compared to no-biochar application.Altogether,the results indicate that the application of urea mixed with biochar could enhance crop performance,especially in the case of activated biochar,which would enhance N retention in the soil,reducing N loss.
基金supported by UGC-Special Assistance Programme by providing the financial assistance to one ofthe authors (NB Devi)
文摘Leaf litterfall,litter decomposition and nutrient return through litterfall of three dominant species,i.e.Quercus serrata,Schima wallichi and Lithocarpus dealbata were studied in different months throughout the year to assess the input and release of nutrient in the forest soil of a sub-tropical mixed oak forest of Manipur,northeastern India.Oaks in northeastern region of India are economically important species for the production of Tasar silk.The monthly litterfall ranged from 25.6 g·m^-2（July） to 198.0 g·m^-2（February） and annual litterfall was 1093.8g·m^-2 in the forest site.At initial month（on November 3）,the concentrations of N and C were the highest in L.dealbata,followed by Q.serrata and lowest in S.wallichi,whereas lignin and cellulose concentrations at initial month were the highest in S.wallichi,followed by Q.serrata and L.dealbata.L.dealbata（k=0.54） exhibited a high rate of litter decomposition,coinciding with high concentrations of N and C and low cellulose in the litter at initial month.However,low rate of litter decomposition in S.wallichi（k=0.33） coincided with low value of N and C and highest value of lignin and cellulose at initial month.The remaining biomass in different months was positively correlated with the lignin,C,C/N ratio and cellulose,but it negatively correlated with nitrogen concentrations at initial month.The rate of litter decomposition was the highest in rainy summer months,owing to congenial environmental conditions and lowest rate of litter decomposition in cool and dry winter months.
基金supported by The University of Burdwan in the form of Ph.D.work(2011-12/2)
文摘We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha-1 a-1 for S. robusta to 11.03 ± 3.72 t ha-1 a-1 for T. grandis and the decay constant （k） of decomposed leaf litter was distinctly higher for T. grandis （2.70 ± 0.50 a-1） compared to S. robusta （2.41 ±0.30 a-1）. Biomass loss was positively correlated with the initial litter C, WSC, C/N and ash content in S. robusta and N, P and K concentration for T. grandis. Biomass was negatively correlated with lignin and L/N ratio for S. robusta and L, WSC, L/N and C/N ratio for T. grandis （P 〈 0.01）. Nutrient use efficiency （NUE） and nutrient accumulation index （NAI） of S. robusta was higher than for T. grandis. The retranslocation of bioelements from senescent leaves ranked as P 〉 N 〉 K. Annual N, P and K input to soil through litterfall differed significantly between the two species in the following order： N〉K^P. S. robusta was superior in terms of K and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release （K 〉 P 〉 N） during decomposition of their leaf litter.Nutrients of N, K and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity.
文摘This study was executed to offer the basis for optimized profit from fertilizer use for sorghum yield and to determine robust crop nutrient response function and economic rate for the production of sorghum at Miesso Central Rift Valley of Ethiopia. Trails were conducted at six experimental sites, sorghum yield response to N and P fertilizers application and economically optimum rates of nitrogen (EONR) and phosphorus (EOPR) were evaluated on a vertisols within the semi-arid Miesso districts west Hararge zone of Oromia region. The nutrient rates in 2014 cropping season four levels of Nitrogen (N) alone, these levels with 20 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> Phosphorus (P) and without N, 69 kg<span style="white-space:nowrap;">·</span>ha<sup><span style="white-space:nowrap;">−</span>1</sup> N with three levels of P treatments including the zero control were evaluated. In 2015, cropping season similar rates of N alone, the same rate N with 20 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> P, 92 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> N with three rates of P including the zero control were evaluated. The treatments were arranged in a randomized complete block with three replications in factorial design. Nutrient responses of sorghum were determined using asymptotic quadratic plateau functions. The significantly highest nitrogen rate was 46 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> alone in 2014 season, which gave grain yield of 2.56 Mg<span style="white-space:nowrap;">·ha<sup>−1</sup></span><sup> </sup>with a maximum yield advantage of 43%. P rates in both seasons and combined (sites + seasons) were not significantly influenced sorghum yield. Nitrogen agronomic and partial factor productivity peaked at 23 kg N <span style="white-space:nowrap;">ha<sup>−1</sup></span> but declined with increasing N rate. The EONR combined (sites + seasons) were 37, 45, 52 and 60 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span><sup> </sup>and for the profit to cost ratio (PCR) were 2.43, 3.65, 4.86 and 5.79 at difference cost to grain price ratios (CP) = 3.6, 2.3, 1.6 and 1.2 respectively at Miesso Ethiopia. Nitrogen application had economically profitable than P. The study concluded that the application of N at 37 or 60 kg N <span style="white-space:nowrap;">ha<sup>−1</sup></span> to sorghum production could be economically profitable for those economically constrained farmers or economically not constrained farmers. Validation should be farther conducted on farmers’ fields for refining the results obtained.
文摘Maize （Zea mays L.） is an important food crop in Niger, but low and irregular rainfall combined with sandy soils having low fertility level limit productivity. A two-year study was conducted at Institut National de Recherche Agronomique du Niger （INRAN） stations in Tarna/Maradi and Bengou/Gaya in 2014 and 2015 in order to evaluate maize agronomic and economic fertilizer use efficiency. The experimental design was a randomised complete block design （RCBD） with three replications. Results indicate higher effect of fertilizer in 2015 compared to 2014. At low N rates 20 kg N/ha and 40 kg N/ha, application of 20 kg P/ha increased maize grain yield across locations and years. The highest agronomic efficiency of N （AEN） was recorded with 60 kg N/ha in 2015 at Bengou and Tarna with 9.65 kg and 14.05 kg grain yield per kg of applied N, respectively. At Tarna, the low N rates of 20 kg N/ha and 40 kg N/ha recorded important AEN of more than 12 kg yield increases per kg of applied N. The highest rainfall use efficiency （RUE） of 6.13 kg/year/mm was obtained with application of 80 kg/ha N, 0 kg/ha P and 40 kg/ha N, 20 kg/ha P in 2015 at Tarna. Without P, the highest value cost ratio （VCR） value of 4.31 was recorded at Tarna in 2015 with 60 kg/ha N, and the lowest value of 0.08 at Bengou in 2014 with 20 kg/ha N. Based on VCR and RUE derived from this study, the optimal fertilizer recommendation for maize in the semi-arid conditions of Niger could be 40 kg/ha N, 20 kg/ha P and 0 kg/ha K.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFD1900805 and Grant No.2018YFD020040608).
文摘Excessive fertilizer application is common in the management of winter wheat (Triticum aestivum L.) in northwest China. However, this practice does not necessarily guarantee higher wheat yield and also causes a waste of resources and environmental pollution. The nitrogen (N), phosphorus (P), and potassium (K) fertilizer application rates need to be optimized to reduce the nitrate residue in the soil while maintaining a high wheat yield. Field experiments were conducted in three consecutive growth seasons (2018-2021) on winter wheat in Northern Xinjiang of China with four reduced fertilization (N-P_(2)O_(5)- K_(2)O) rates (FS1: 166-80-30 kg/hm^(2), FS2: 0-80-30 kg/hm^(2), FS3: 166-0-30 kg/hm^(2), FS4: 166-80-0 kg/hm^(2)) and the local fertilization rate (CK: 240-105-38). The soil nutrients, nutrient uptake content of organ, dry matter accumulation, yield, and fertilization use efficiency were investigated. The results showed increasing NH_(4)^(+)-N concentrations in the soil over the three growing seasons, while NO_(3)^(-)-N concentrations decreased in the later experimental years. High soil NH_(4)^(+)-N concentration and low soil NH_(4)^(+)-N residues were observed in FS3. When the control fertilization (CK) was applied, the grains had a higher proportion of N and P, while the N content in grains was relatively low at the high fertilization rate. When the fertilizer supply was insufficient (FS2, FS3, and FS4), the proportion of vegetative organs to the total biomass was relatively low. Lower fertilization rates resulted in higher N, P, and K use efficiencies in 2019-2020 and 2020-2021, in comparison to those at higher rates, while FS2 exhibited the highest fertilizer use efficiency. When fertilization (CK) was sufficient, the dry matter accumulation decreased by 3.33%- 17.08%, and the harvest index increased by 0.87%-47.40%. FS1 had the highest spike number, which significantly increased by 17.98%, 17.80%, and 9.64% compared with CK during 2018-2019, 2019-2020, and 2020-2021, respectively. In conclusion, a reduction in fertilizer application compared with CK could provide excellent production results. The optimal drip fertigation approach for winter wheat production in the arid regions of northwest China was determined to be the N-P_(2)O_(5)-K_(2)O application rate of 166-80-30 kg/hm^(2) when comprehensively considering the winter wheat yield, soil NH_(4)^(+)-N, and NH_(4)^(+)-N, N use efficiency, P use efficiency, and K use efficiency. This research can provide a scientific basis for the responses of winter wheat production to nutrient uptake of drip-irrigated winter wheat in arid and semi-arid regions.
基金supported by the Major Sate Basic Research Development Program of China (No. 2013CB127401)the National Science Foundation of China (No. 41271309)the Postdoctoral Science Foundation of Jiangsu (No. 140064C)
文摘Point placement of urea is an efficient technology to improve urea use efficiency in transplanted rice(Oryza sativa L.), but it is largely unknown how nutrient composition in the point placement and the distance from placement site to the plant influence rice root distribution and growth, nutrient uptake, and rice grain yield. A controlled greenhouse experiment was conducted using both N-and P-deficient soil with point placement of N only or N and P together(N + P) at a distance close to or far from the plant,in comparison to an N-spilt application and a no-N control. Both nutrient composition and distance significantly affected rice root growth. Compared with the N point placement, the N + P point placement led to smaller root length and mass densities, higher specific root length(SRL) around the placement site, smaller root system, higher straw mass and grain yield, and higher N and P uptake. The difference between the N + P and N point placements was greater when close to the plant than when far from the plant. It is suggested that higher SRL around the placement site is essential for improving nutrient uptake and rice grain yield, and simultaneous point placement of N and P has a synergistic effect on rice growth.
基金supported by the National Natural Science Foundation of China(Grant Nos.32071632,31600427)the National Science Foundation of Shaanxi Province,China(Grant Nos.2022JM-114,2019JQ-666)
文摘Background Enzymatic stoichiometry reflects microbial relative resource limitations by linking microbial nutritional demands with soil nutrient availability,yet how plant invasion-induced changes in vegetation,soil properties,and microbial communities modulate these limitations and metabolic efficiency remains undetermined.Here,we employed enzymatic stoichiometry and vector modeling to assess microbial relative resource limitations in invasive Spartina alterniflora salt marsh in comparison to those in bare flat and in native Suaeda salsa and Phragmites australis salt marshes,and systematically linked these limitations to microbial carbon(C)and nitrogen(N)use efficiencies(CUE and NUE,respectively)across coastal wetland ecosystems of eastern China.Results Our analyses showed predominant phosphorus(P)limitation of soil microbial metabolism in bare flat and native S.salsa and P.australis salt marshes,contrasting with dual C-P co-limitation observed in invasive S.alterniflora salt marsh.S.alterniflora invasion intensified microbial P limitation compared with bare flat,while simultaneously inducing the most pronounced C limitation among all plant communities.The microbial C limitation induced by S.alterniflora invasion drove reductions in microbial CUE,whereas microbial NUE increased,establishing an antagonistic relationship between these metabolic efficiencies.Microbial resource constraints and nutrient use efficiencies(CUE/NUE)in soils were coordinately controlled by plant traits,soil properties,and microbial attributes.Partial least squares path modeling analysis identified soil organic C(SOC)chemical fractions(e.g.,aromatic C,alkyl C,dissolved organic C)as predominant positive drivers of microbial C limitation and NUE,while simultaneously suppressing microbial CUE.Simultaneously,plant traits were identified as the foremost contributor to microbial P limitation,followed by microbial attributes as the second-most influential positive factor.Conclusions This study revealed that S.alterniflora invasion fundamentally shifted microbial nutrient limitation from predominant P limitation in bare flat and native salt marshes to dual C-P co-limitation,while simultaneously inducing the strongest microbial C limitation among all communities.This invasion-induced microbial C limitation drove a reduction in microbial CUE but an enhancement of NUE.SOC accumulation increased with decreasing microbial CUE following S.alterniflora invasion,a tradeoff potentially linked to divergent nutrient limitations across ecosystems.This study provided empirical evidence for microbially-mediated soil C sequestration mechanisms underlying plant invasion-induced ecosystem transformations.
