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1.
In this study, four different methods for reference crop evapotranspiration (ET0) were calibrated and validated for estimation of daily to mean monthly ET0 by weighing lysimeter data during 2005–2006 and 2004–2005, respectively, in a semi-arid region. The value of the constant in the Hargreaves–Samani method changed from 0.0023 to 0.0026 for daily to mean monthly ET0, and can be used in stations with only air temperature data. The constant of the aerodynamic resistance equation in the FAO-56 Penman–Monteith method (208.0) changed to 85.0. The value of coefficient a in the FAO-24-Radiation method was between ?0.5 and ?0.67. Further, the empirical equations were modified to estimate the value of b in the FAO-24-Radiation method and C in the FAO-24 corrected Penman method. The results showed that the modified FAO-56, corrected Penman–Monteith and FAO-24-Radiation methods are the most appropriate for estimating daily to mean monthly ET0. Furthermore, the modified FAO-24 corrected Penman method was ranked in fourth place and its accuracy was lower than that of the other methods. However, it is appropriate for estimating mean monthly ET0. Smoothing the daily data decreased the fluctuation in measured daily weather data and ET0 measured by lysimeter, and consequently resulted in a higher accuracy in the estimation of daily ET0.  相似文献   

2.
Proper methods for estimating reference evapotranspiration (ET0) using limited climatic data are critical, if complete weather data are unavailable. Based on the weather data of 19 stations in Guizhou Province, China, several simple methods for ET0 estimation, including the Hargreaves, Priestley–Taylor, Irmak–Allen, McCloud, Turk, and Valiantzas methods, were involved in comparison with the standard FAO-56 Penman–Monteith (PM) method. The Turk equation performs well for estimating ET0 in humid locations. Both the Turk method and the Valiantzas method initially performed acceptably with mean root-mean-square difference (RMSD) of 0.1472 and 0.1282 mm d?1, respectively, with only requiring parameters of temperature (T), relative humidity (RH), and sunshine duration (n). The corresponding calibration formulas to Turk and Valiantzas method were suggested as the most appropriate method for ET0 estimation with the RMSD of 0.0098 and 0.0250 mm d?1, respectively. The local calibrated Hargreaves–Samani method performed well and can be applied as the substitute of FAO-56 PM method under the condition that only the daily mean, maximum, and minimum temperatures were available, and local calibrated McCloud method was acceptable if only the mean temperature was available.  相似文献   

3.
In this paper, the daily reference evapotranspiration (ET0) for Bulawayo Goetz was estimated from climatic data using neuro computing techniques. The region lacks reliable weather data and experiences inconsistencies in the measuring process due to inadequate and obsolete measuring equipment. This paper aims to propose neuro computing techniques as an alternative methodology to estimating evapotranspiration. Firstly, ET0 was calculated using FAO-56 Penman-Monteith (PM) equation from available climatic data. Data was divided into training, testing and validation for neuro computing purposes. The study also investigated the effect of different normalisation techniques on neuro computing ET0 estimation accuracy. In another application, neuro-computing ET0 estimates were compared against those obtained using empirical methods and their calibrated versions. The Z-score normalisation technique for all data sets gave best results with a Multi-layer perceptron (5–5-1) model having RMSE, MAE and R2 values in the range 0.12–0.25 mm day?1, 0.08–0.15 mm day?1 and 0.94–0.99 respectively. There were no significant differences in ET0 estimation accuracy by neuro computing techniques due to normalisation technique. The Neuro computing techniques were superior to empirical methods in ET0 estimation for Bulawayo Goetz. The Neuro computing techniques are recommended for use in cases of limited climatic data at Bulawayo Goetz.  相似文献   

4.
Accurate daily reference evapotranspiration (ETo) forecast is essential for real-time irrigation scheduling. An attempt was made to forecast ETo using the Blaney–Criddle (BC) model and temperature forecasts in this study. Daily meteorological data for the period 2000–2014 at five stations in East China were collected to calibrate and validate the BC model against the FAO56 Penman–Monteith (FAO56-PM) model. Temperature forecasts up to 7 days’ lead time for 2012–2014 were input to the calibrated BC model to forecast ETo. It is found that the performance of the BC model for ETo forecast is further improved at all stations after monthly calibration. Average accuracy of forecasted ETo (error within 1.5 mm d?1) ranged from 82.7% to 89.3%, average values of mean absolute error (MAE) varied between 0.73 and 0.82 mm d?1, average values of root mean square error (RMSE) ranged from 0.95 to 1.08 mm d?1, and average values of the correlation coefficient (R) and concordance index (d) were more than 0.75 and 0.89, respectively. Furthermore, the error in ETo forecast caused by error in temperature forecast is acceptable. The encouraging results indicate that the proposed method can be an alternative and effective solution for forecasting daily ETo in East China.  相似文献   

5.
The current study aims to improve the performance of simple methods for the estimation of daily reference evapotranspiration (ET0) in humid East China, namely Priestley–Taylor 1972 (P-T 1972), Hargreaves–Samani 1985 (H-S 1985) and Turc 1961 (TU 1961). These methods were evaluated and calibrated based on well-watered grass lysimeter experiments. The FAO-56 Penman–Monteith equation (FAO-56 PM) is the best method, and the radiation-based methods (TU 1961 and P-T 1972) perform much better than the temperature-based method (H-S 1985). In the simple methods, the coefficients are calibrated to: 1.34 for P-T 1972; 0.0186, 23.47 and 17.06 for TU 1961; and 0.0027 and 0.449 for H-S 1985. The locally calibrated TU 1961 and P-T 1972 perform much better than the original, with either the observed ET0r or the ET0c obtained by FAO-56 PM as standard. However, local calibration does not significantly improve the performance of the H-S 1985 method. In humid East China, FAO-56 PM is the best method for daily ET0 calculation. TU 1961, especially if locally calibrated, is the optimal choice as a simple substitute for FAO-56 PM when solar radiation is available. Otherwise, serious local calibration is strongly recommended before applying H-S 1985 for daily ET0 estimation.  相似文献   

6.
In recent years, the availability of near real-time and forecast standardized reference evapotranspiration (E0) has increased dramatically. Use of the E0 information in conjunction with calibration coefficients that adjust for differences between the vegetation and the reference surface provides a method to greatly improve the estimates of actual evapotranspiration (Ea) from landscapes (or ecosystems). Difficulties in estimating evapotranspiration (ET) of well-watered vegetation in an ecosystem depend on local advection and edge effects, wide variations in radiation resulting from undulating terrain, wind blockage or funnelling, and differences in temperature due to spatial variation in radiation, wind, etc. Estimating the ET of an ecosystem that is water stressed is even further complicated because of stomatal closure and reduced transpiration. The Ecosystem Water Program (ECOWAT) was developed to help improve estimates of Ea of ecosystems by accounting for microclimate, vegetation type, plant density, and water stress. The first step in estimating Ea is to calculate E0 using monthly climate data from one representative weather station in the study area. Then, local microclimate data are used to determine a standardized reference evapotranspiration for the local microclimate (Em). The ratio Km = Em/E0 is calculated and applied as a microclimate correction factor to estimate Em. The product of Em and a vegetation coefficient (Kv = Ev/Em) is used to estimate the evapotranspiration of the ecosystem vegetation (Ev) under well-watered conditions with a full-canopy cover within the same microclimate. Next, a coefficient for plant density (Kd), which is based on the percentage ground cover, is used to adjust the full-canopy Ev to the evapotranspiration of a sparse canopy from a well-watered ecosystem (Ew). A stress (Ks) coefficient, which varies between 1.0 with no stress to 0.0 with full stress, is determined as a function of available water in the root zone. The predicted actual ecosystem evapotranspiration (Ep) is estimated as Ep = Ew × Ks. In this paper, we present how the ECOWAT model works and how it performs when the predicted actual evapotranspiration (Ep) is compared with measured actual evapotranspiration (Ea) collected in several Mediterranean ecosystems (three in Italy and two in California) over a number of years. The potential use of ECOWAT in integrated fire danger systems is discussed.  相似文献   

7.
Leaf Area (LA) is a key index of plant productivity and growth. A multiple linear regression technique is commonly applied to estimate LA as a non-destructive and quick method, but this technique is limited under the realistic situation. Thus, it is indispensable to elaborate new models for estimation. In this research, the performance of the Adaptive Neural-Based Fuzzy Inference System (ANFIS) in predicting the LA of 61 plant species (C) was investigated. Four parameters including leaf length (L), leaf width (W), C, and specific coefficient (K) for each plant were selected as input data to the ANFIS model and the LA as the output. Seven different ANFIS models including different combinations of input data were constructed to reveal the sensitivity analysis of the models. The normalized root mean square error (NRMSE), mean residual error (MRE), and linear regression were applied between observed LA and estimated LA by the models. The results indicated that ANFIS4-K2min which employed all input data was the most accurate (NRMSE = 0.046 and R2 = 0.997) and ANFIS1 which employed only the K input was the worst (NRMSE = 0.452 and R2 = 0.778). In ranking, ANFIS4-K2ave, ANFIS4-K1min, ANFIS4-K1ave, ANFIS3, and ANFIS2 ranked second, third, fourth, fifth, and sixth, respectively. The sensitivity analysis indicated that the predicted LA is more sensitive to the K, followed by L, W, and C. The results displayed that estimations are slightly overestimated. This study demonstrated that the ANFIS model could be accurate and faster alternative to the available laborious and time-consuming methods for LA prediction.  相似文献   

8.
The long-term probability of soil moisture stress in rainfed crops was mapped at 0.5° resolution over the Krishna River basin in southern India (258,948 km2). Measurements of actual evapotranspiration (Ea) from 90 lysimeter experiments at four locations in the basin were used to calibrate a non-linear regression model that predicted the combined crop coefficient (KcKs) as a function of the ratio of seasonal precipitation (P) to potential evapotranspiration (Ep). Crops included sorghum, pulses (mung bean, chickpea, soybean, pigeonpea) and oilseeds (safflower and sunflower). Ep was calculated with the Penman–Monteith equation using net radiation derived from two methods: (1) a surface radiation budget calculated from satellite imagery (EpSRB) and (2) empirical equations that use data from meteorological stations (EpGBE). The model of Ks as a function P/Ep was combined with a gridded time series of precipitation (0.5° resolution, 1901–2000) and maps of EpSRB to define the probability distributions of P, P/Ep and Ks for sorghum at each 0.5° cell over the basin. Sorghum, a C4 crop, had higher Ea and Ks values than the C3 plants (oilseeds, pulses) when precipitation was low (P < 1 mm d−1) but lower maximum Ea rates (3.3–4.5 mm d−1) compared with C3 crops (oilseeds and pulses, 4.3–4.9 mm d−1). The crop coefficient under adequate soil moisture (Kc) was higher than the FAO-56 crop coefficients by up to 56% for oilseeds and pulses. The seasonal soil moisture coefficient (Ks) for sorghum ranged from 1.0 under high rainfall (July–October) to 0.45 in dry seasons (November–March), showing strong soil moisture controls on Ea. EpSRB calculated at the lysimeter stations was 4–20% lower than EpGBE, with the largest difference in the dry season. Kc derived from EpSRB was only slightly (2–4%) higher than Kc derived from EpSRB, because the maximum Ea occurred during the monsoon when the differences between EpSRB and EpGBE were small. Approximately 20% of the basin area was expected to experience mild or greater soil moisture stress (Ks < 0.80) during the monsoon cropping season 1 year in every 2 years, while 70% of the basin experienced mild or greater stress 1 year in 10. The maps of soil moisture stress provide the basis for estimating the probability of drought and the benefits of supplemental irrigation.  相似文献   

9.
The lime requirement (LR) in 39 surface acid soil samples (0–30 cm) from western Greece was calculated using a single-addition titration of successive 3-mL 0.022 M calcium hydroxide [Ca(OH)2]. Soil pH measurements and titrations were performed in soil/water (1:2) and in a soil/0.01 M CaCl2 (1:2) suspension while being stirred. The results were referred to as ‘pH data group I’ and ‘pH data group II’, respectively. In each ‘pH data group’, the samples were separated into ‘pH data subgroups’, according to the total volume (mL) of 0.022 M Ca(OH)2 added to increase the initial pH (pHa) to a target value of 6.5 (pHt). The fitted linear regression equation pHt = b × volume + pHa was used for each ‘pH data group’ to determine the slope b. The b-weighted mean for each ‘pH data group’ was calculated. The LR was then calculated as follows: Mg CaCO3 ha?1 = 0.495 (pHt – pHa)/b, where b is the average weighted mean from the two ‘pH data groups’ and is equal to 0.227. The validity of the above equation was confirmed after incubation with Ca(OH)2 for 72 h. This procedure is simple and gives a rapid and accurate estimation of LR with respect to the environment.  相似文献   

10.
Short-term forecasting of daily crop evapotranspiration (ETc) is essential for real-time irrigation management. This study proposed a methodology to forecast short-term daily ETc using the ‘Kc-ETo’ approach and public weather forecasts. Daily reference evapotranspiration (ETo) forecasts were obtained using a locally calibrated version of the Hargreaves-Samani (HS) model and temperature forecasts, while the crop coefficient (Kc) was estimated from observed daily ETo and ETc. The methodology was evaluated by comparing the daily ETc forecasts with measured ETc values from a field irrigation experiment during 2012–2014 in Yongkang Irrigation Experimental Station, China. The overall average of the statistical indices was in the range of 0.96–1.27 mm d?1 for the mean absolute error (MAE), 1.53–2.55 mm d?1 for the mean square error (MSE), 1.77–2.30 mm d?1 for the normalized mean square error (NMSE), 27.5–29.4% for the mean relative error (MRE), 0.71–0.44 for the correlation coefficient (R) and 0.46–0.05 for the mean square error skill score (MSESS). Sources of error werewere Kc estion, temperature forecasts and HS model that does not consider wind speed and humidity, and.the largesourceof error is Kc determination, which suggested that care should be taken when forecasting ETc with estimated Kc values in the study area.  相似文献   

11.
In this research, radiation use efficiency (RUE) of winter wheat was determined under different irrigation regimes and nitrogen application rates in experimental field at southwest Iran (semi-arid region) in 2009–2010 and 2010–2011. The experiment was laid out as a split plot design, with irrigation treatments as main plots and N fertilization as sub-plots with three replications. Irrigation treatments were 1.2 (I4), 1.0 (I3), 0.8 (I2), and 0.5 (I1) times of the full irrigation requirements and N treatments were 0 (N1), 46 (N2), 92 (N3), and 136 (N4) kg ha?1. Air temperature had significant effects on RUE that was adjusted by multiplication of hourly temperature factor to the hourly values of solar radiation (RUE a ). The values of RUE a were significantly different from the values of RUE in both growing seasons. The values of RUE a ranged from 1.44 to 1.83 g MJ?1 and 1.45 to 1.81 g MJ?1 in 2009–2010 and 2010–2011, respectively. In both growing seasons, minimum and maximum values of RUE were at I1N1 and I4N4 treatments, respectively. The methods of daily maximum and minimum air temperature were modified for considering the effects of air temperature on RUE at locations where hourly air temperature and radiation were not available.  相似文献   

12.
Drought stress is an important factor limiting the yield potential of peanut. In order to determine the effect of different irrigation scenarios on peanut production, field experiments were conducted in 2011 and 2012 growing seasons using factorial design with three replicates. On the other hand, the crop simulation models can be useful to predict crop yields and to investigate the impact of drought stress on plant growth and development. In this study, the Cropping System Model–Crop Growth (CSM-CROPGRO)-Peanut model was employed for the simulation of seed yield, pod yield, biomass, soil water balance components and water productivity for peanut in Astaneh-Ashrafiyeh, Iran. Results showed that the model was able to reasonably simulate seed yield, pod yield and final biomass for different irrigation scenarios (RMSEn < 20%, R2 > 0.8 and d > 0.8). According to the results, irrigation depth and interval were important factors affecting yield and biomass. In general, model error increased as the amount of water applied decreased. The least amount of water applied (40 mm) resulted in yield reductions by 76%, 70% and 67% of the greatest amount of water applied (480 mm) for seed yield, pod yield and final biomass, respectively. For each irrigation interval, larger irrigation depth led to lower water productivity (WP) of irrigation (WPI), but higher WP based on evapotranspiration (WPET) and transpiration (WPT).The average amounts of WPI, WPET, WPT based on seed yield were 1.2, 0.63 and 1.01 kg m?3, respectively.  相似文献   

13.
Field-applied salicylic acid (SA) could provide a potential protection against drought stress in onion large-scale production. Two-season field experiments were consecutively conducted in 2013/2014 and 2014/2015 to study the effect of 1 and 2 mM SA on growth, yield, plant water relations, chlorophyll a fluorescence, osmoprotectants, and water-use efficiency (WUE) in onion plants under four levels of irrigation (I120 = 120%, I100 = 100%, I80 = 80%, and I60 = 60% of crop evapotranspiration). Foliar application of SA enhanced drought stress tolerance in onion plants by improving photosynthetic efficiency and plant water status as evaluated by membrane stability index and relative water content. These results were positively reflected by improving plant growth, productivity, and WUE under drought stress conditions. Therefore, SA application may, in future, find application as a potential growth regulator for improving plant growth and yield under deficit irrigation by 20–40%.  相似文献   

14.
This study investigated the impacts of organic- and clay-based soil amendments, and their combinations on crop water productivity (CWP) using maize as a test crop. On-station field trials were established over two consecutive years at the Naphok and Veunkham sites in Laos. At each site, 10 treatments were applied in a randomized complete block design with three replications. The treatments were control, rice husk biochar (10 t ha?1), bentonite clay (10 t ha?1), compost (4 t ha?1), clay-manure compost (10 t ha?1), rice husk biochar compost (10 t ha?1), bentonite clay + biochar, bentonite-clay + compost, biochar + compost, and bentonite clay + biochar + compost. All treatments were applied in 2011. Significant (p < 0.05) treatment effects in CWP and growing period evapotranspiration were determined. At Naphok, differences between the amended and control plots in CWP varied between 0.1 and 0.6 kg m?3 in 2011 and from 0.1 to 0.4 kg m?3 in 2012, whereas differences at Veunkham varied between 0.3 and 1.0 kg m?3 in 2011 and from 0.05 to 0.29 kg m?3 in 2012. At both sites, CWP in 2012 was significantly lower than 2011. Our results illustrate that organic- and clay-based soil amendments improve CWP, indicating that soil-based interventions could be suitable options for improving agricultural productivity.  相似文献   

15.
Crop water parameters, including actual evapotranspiration, transpiration, soil evaporation, crop coefficients, evaporative fractions, aerodynamic resistances, surface resistances and percolation fluxes were estimated in a commercial mango orchard during two growing seasons in Northeast Brazil. The actual evapotranspiration (Ea) was obtained by the eddy covariance (EC) technique, while for the reference evapotranspiration (E0); the FAO Penman–Monteith equation was applied. The energy balance closure showed a gap of 12%. For water productivity analysis the Ea was then computed with the Bowen ratio determined from the eddy covariance fluxes. The mean accumulated Ea for the two seasons was 1419 mm year−1, which corresponded to a daily average rate of 3.7 mm day−1. The mean values of the crop coefficients based on evapotranspiration (Kc) and based on transpiration (Kcb) were 0.91 and 0.73, respectively. The single layer Kc was fitted with a degree days function. Twenty percent of evapotranspiration originated from direct soil evaporation. The evaporative fraction was 0.83 on average. The average relative water supply was 1.1, revealing that, in general, irrigation water supply was in good harmony with the crop water requirements. The resulting evapotranspiration deficit was 73–95 mm per season only. The mean aerodynamic resistance (ra) was 37 s m−1 and the bulk surface resistance (rs) was 135 s m−1. The mean unit yield was 45 tonne ha−1 being equivalent to a crop water productivity of 3.2 kg m−3 when based on Ea with an economic counterpart of US$ 3.27 m−3. The drawback of this highly productive use of water resources is an unavoidable percolation flux of approximately 300 mm per growing season that is detrimental to the downstream environment and water users.  相似文献   

16.
Accurate estimation of reference evapotranspiration (ETo) is essential for water resources management and irrigation systems scheduling, especially in arid and semiarid regions such as Iran. In the present research, constant coefficients of Hargreaves–Samani (CH–S) and Priestley–Taylor (CP–T) equations were locally calibrated to estimate the ETo based on the FAO–Penmen–Monteith (PM) method as standard method. For this purpose, meteorological data of eight synoptic stations located in the northwest of Iran were used during the period of 1997–2008. The outcomes showed that the values of CH–S and CP–T were 0.0026 (instead of 0.0023) and 1.68 (instead of 1.26), respectively. Also, at stations with high wind speed, the values of calibrated coefficients of CH–S and CP–T were maximum. Then, the estimated ETo values using adjusted CH–S and CP–T coefficients were compared to the obtained actual ETo values by PM method using root mean square error and mean bias error indices. The results indicated that the new calibrated H–S and P–T equations have good agreement with the PM method for estimation of the ETo. Moreover, the equation of Ravazzani et al. was calibrated in the studied region. It was concluded that in general, the mentioned equation was shown better performance than original H–S equation.  相似文献   

17.
A 4-year (2008–2009 to 2011–2012) study was conducted on the effect of mineral phosphorus (P) + sulphur (S) and biofertilizers on rain-fed chickpea (Cicer arietinum L.) at the Punjab Agricultural University’s Research Station, Ballowal Saunkhri, India. The experiment comprised of five combinations of P and S, viz. control (P0S0), no P + 10 kg S ha?1 (P0S10), 15 kg P + 10 kg S ha?1 (P15S10), no P + 20 kg S ha?1 (P0S20) and 30 kg P + 20 kg S ha?1 (P30S20); and three seed inoculation levels, viz. control, Rhizobium and phosphate-solubilizing bacteria (PSB), were laid out in randomized complete block design. Combined application of P + S resulted in improved growth, nodulation, yield attributes and yield. The increase in seed yield over control due to P + S ranged from 11.8% to 17.7%. Seed inoculation with Rhizobium recorded the highest growth, nodulation, yield attributes and yield of chickpea and was statistically at par with PSB and significantly better than no inoculation. Highest benefit/cost ratio (B:C, 2.19) was obtained in P30S20. In view of environmental pollution and high costs of chemical fertilizers, biofertilizers alone or in combination may help to achieve sustainable and ecological agricultural production.  相似文献   

18.
Agriculture is the major consumer of water and it is possible to decrease water consumption in this sector by proper irrigation scheduling. Irrigation scheduling is based on crop water requirements. Saffron is an important crop in Iran. The main purpose of this study was to determine the potential evapotranspiration and crop coefficient for saffron using single and dual crop coefficients, in Badjgah region, College of Agriculture, Shiraz University, Shiraz, Iran. Three water-balance lysimeters were used for this experiment in a two-year study. Total saffron potential evapotranspiration values were 523 and 640 mm in the first and second growing seasons, respectively. The maximum evapotranspiration rates for saffron were 4.5 and 6.1 mm d?1 in the first and second growing seasons, respectively. Based on the results of this study, different saffron growing stages for evapotranspiration were 30, 40, 70 and 60 days. Crop coefficient (K c) values for the initial, mid- and late-season growth stages were 0.41–0.45, 0.93–1.05 and 0.29–0.31 in both years, respectively. Basal crop coefficient (K cb) values for the initial, mid- and late-season growth stages were 0.15–0.16, 0.41–0.65 and 0.15–0.17 in both years, respectively.  相似文献   

19.
Water loss as deep percolation is considerable in furrow irrigation in light soils due to the high infiltration rate. Application of soil conditioners such as bentonite reduces the infiltration rate and improves irrigation application efficiency (Ea) in these soils. The effects of bentonite application rates (BAR) of 0, 2, 4 and 6 g L?1 on infiltration of a loamy sand soil were determined in a soil column in the laboratory. The exponent of the Kostiakov infiltration equation was not influenced by BAR. Maximum reduction in infiltration equation coefficient and final infiltration rate (i f) occurred with 2 g bentonite L?1 and this reduction was lower on increasing BAR from 2 to 4 and 4 to 6 g L?1 compared with control. The effect of 2 g L?1 BAR on infiltration and its effect on the design of furrow irrigation in a field with a loamy sand soil indicated that in the first irrigation after field ploughing and seed planting, longer furrow length, lower deep percolation and higher Ea are obtained.  相似文献   

20.
Phosphate-solubilizing fungal strains were isolated from organically managed soil and tested for their ability to solubilize rock phosphate (RP), ferric phosphate and aluminium phosphate. These strains were identified as Aspergillus tubingensis and Aspergillus niger based on internal transcribed spacer sequence analysis. A field study was conducted in two different seasons in organically managed soil to test the efficacy of two strains, A. tubingensis (PSF-4) and A. niger (PSF-7) on the yield and soil fertility. RP was amended at the rate of 59 kg P2O5 ha?1 to study the effect of RP on soil fertility. The maize was grown in rainy season (July–October 2011) and wheat in winter season (November 2011–April 2012). Plant heights, shoot and root dry biomass and phosphorous (P) uptake in roots, shoots and grains were significantly increased due to inoculation in both crops. The yield of maize and wheat were significantly increased when inoculated along with RP fertilization. Organic carbon, P levels and soil enzyme activities were significantly increased due to inoculation. Results of present study suggested that A. tubingensis and A. niger improved the crop yield and soil fertility of organic farm when inoculated with RP fertilization.  相似文献   

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