Thin-layer Drying Characteristics and Modeling of Two Varieties Green Malt

Malting process includes steeping, germination and kilning of cereal grains in controlled conditions. The Kilning process is the most expensive stage of malting industry. In the present study, drying behavior of green malt of two different barley varieties （Sahra and Dasht） were evaluated at air temperatures ranging from 40 to 85 ℃, at constant air velocity of 6 m/s. The main objective of this research was to select the best drying equations, in order to use them for the calculation of drying time and energy consumption. For that the experimental data was fitted to five thin layer drying equations （Lewis, Henderson and Pabis, Page, Modified page and Two-term）. The coefficients of the equations were compared by three statistical parameters as residual sum of squares, standard error of estimate and mean relative deviation. The effect of temperature on the coefficients of the five selected equations was evaluated by linear regression. The results show that The Page model was found to be most suitable in describing the drying characteristics of green barley malt because of that has the lowest statistical parameters. The color of green barley malt was determined after drying using a spectro-colorimeter （Hunter Lab） in terms of Hunter L, a, and b values. Color measurement indicated that the AE index increased with an increase in drying air temperature.     

Application of Neutron Activation Analysis Technique for the Analysis of Soil Samples from Farmlands of Yebrage Hawariat,East Gojjam,Ethiopia

Farmers may not be conscious for their farmland＇s nutrients, soil organic matter, water and air because they simply concerned only for their labor availability and soil fertility losses. The composition and proportion of these components greatly influence soil physical properties, including texture, structure and porosity, the fraction of pore space in a soil. The soil of this farmland must be able to supply adequate amount of plant nutrients, in forms which can be absorbed by the crop, within its lifespan. Deficiencies or imbalances in the supply of any of essential elements can compromise growth, affecting root development, cell division, crop quality, crop yield and resistance to disease and drought. This study was conducted to fill this knowledge gap in order to develop economically vital and environmentally accepted nutrient management strategies for the use of soils in agricultural lands. The objective of this study is to assess the elemental contents and concentration of soil samples collected from farmlands of ＂Yebrage＂ using neutron activation analysis （NAA） techniques regardless of oxidation state, chemical form or physical locations. NAA is used to determine the elemental composition and concentrations present in a soil. The macro/micronutrient and organic matter deficiencies have been verified in agricultural soils through increased use of soil testing and plant analysis. The challenge for agriculture over the coming decades will meet the world＇s increasing demands for food in a sustainable way. Current issues and future challenges point out that as long as agriculture remains a soil based industry, major decreases in productivity likely to be attained ensuring that plants do not have adequate and balanced supply of nutrients.     

Distribution and Identification of Ixodid Tick Species on Livestock in Northern Pakistan

Identification of lxodid tick species on livestock in two districts, viz., D.I. Khan and Lakki Marwat of Northern Pakistan were made during the period from March to November 2009 through animals＇ survey and questionnaire. The main tick species were Amblyomma （14.3%）, Boophilus microplus （l 8.5%） and Hyalomma anatolicum and H. dromedarii （67.2%）. Out of 3009 collected ticks, the highest number of female （88.7%） and the lowest of males （ l 1.3%） belong to Boophilus; the lowest number of female （92.4%） and the highest of males （77.5%） belong to Amblyomma. However, cows were more susceptible than buffaloes and camels ranked third to ticks infestation. Moreover, cows, buffalos, goats and sheep harbored mixed infestation （had more than one type of ticks）, however, camels and donkey harbored single infestation （had only one type of tick）. An emerging ethno-veterinary or traditional remedy is poultry keeping for ticks＇ elimination in Lakki Marwat. The results of this research will be helped in taking appropriate measures to reduce tick infestation and to improve management practices. Hence, it will help to increase farm productivity and farmers income.     

Impacts of Climate Change on Rice Yield in China From 1961 to 2010 Based on Provincial Data

The impacts of climate change on rice yield in China from 1961 to 2010 were studied in this paper, based on the provincial data, in order to develop scientiifc countermeasures. The results indicated that increase of average temperature improved single cropping rice production on national level by up to 11%relative to the average over the study period, however, it resulted in an overall loss of double cropping rice by up to 1.9%. The decrease of diurnal temperature range （DTR） in the major producing regions caused the decrease by up to 3.0%for single cropping rice production and 2.0%for double cropping rice production. Moreover, the contribution of precipitation change reached about 6.2%for single cropping rice production, but no signiifcant effect for double cropping rice production in recent 50 years.     

Effects of Elemental Sulphur and Farmyard Manure on pH and Salinity of Calcareous Sandy Loam Soil and Some Nutrient Elements in Tomato Plant

The objective of this study was to evaluate the effects of elemental sulphur （S） and farmyard manure on soil pH, EC and N, S, P concentrations of tomato grown in a calcareous sandy loam soil. For this purpose, a pot experiment was conducted in greenhouse conditions. Sulphur was applied at 0, 50, 100, 150, 200, 400 mg kg~ and farmyard manure at 0, 3 ton da^-1 to the soil. Three weeks after applications, tomato seedlings were planted and 8 weeks later, the plants were harvested to determine N, S, P concentrations and dry matter yield. Soil pH and EC were determined in the soil samples taken at 3 different periods. Effects of sulphur and farmyard manure applications were not significant on N, P concentrations and dry matter yield of tomato plant. S concentration of tomato plant was increased by sulphur alone. Soil pH was decreased and soil EC was increased in both 2^nd and 3^rd soil sampling period by the sulphur applications. As a result of farmyard manure application, soil pH decreased in the 2^nd soil sampling period but increased in the 3^rd soil sampling period. Also, soil EC was significantly increased in 1^st and 3^rd soil sampling period. Farmyard manure had no significant effect on S supply to tomato plant. The N：S ratio of tomato plant was decreased by sulphur alone. However, the sulphur with farmyard manure applications decreased N：S ratio in lesser extend compared to the S applications.     

Under-Winter Sowings of Red Beetroot in Uzbekistan

The results of the three-year researches which had the purpose to establish an optimum depth of seeding at sowing and rational norm of seeding of red beetroot seeds at under-winter sowing in conditions of mid-loamy typical grey soils of the central climatic zone of Uzbekistan are stated in article. The researches were spent at statement of field experiences in quadruple frequency with the area of a registration allotment 10 M^-1. Crops were carried out in the first decade of December against mulching surfaces of ridges by humus and without mulching. Crops were carried out on ridges in width of 70 sm tape-two-lined with distance between tapes of 50 sm, between lines-20 sm and distance between plants in a line of 12-13 sm, at density of standing of 228-230 thousand plants/hectares. Experiences were spent with zoned in Uzbekistan multi-seedling grade of a red beetroot ＂Bordo 237＂. Experiences were accompanied by phenological supervision, biometric accounts, the account of field germination of seeds, density of standing of plants and definition of size and quality of a crop. Results of researches were exposed to the statistical analysis by a dispersive method. It has been revealed that at under-winter sowing of a red beetroot the effective way providing acceleration of shoots occurrence, formations of high-grade density of standing and increase of productivity of root crops is mulching the surfaces of ridges by humus. It is defined that optimum depth of seeding at sowing both at application of mulching and without it is the depth of seeding 4 sm. It is established that the most rational norm of seeding of the seeds, providing high-grade density of standing, is at cultivation with application of mulching 8 kg/ha, and at cultivation without mulching 8-10 kg/ha. Application of mulching the surfaces of ridges by humus, depths of seeding of 4 sm and norms of seeding of seeds of 8-10 kg/ha in conditions of under-winter sowing in comparison with cultivation without mulching and depth of seeding 2 sm and norms of seeding of 6 kg/ha provides an acceleration of receipt of fresh production of a red beetroot for 12-14 days and considerably raises root crops productivity. Application of agro receptions improved by us is the important reserve of acceleration of receipt of red beetroot early production and increase of its manufacture.     

Cooking Quality Parameters of Rice Cultivars Grown in Spain

The quality office is complex and made up of many components such as nutritional quality, appearance, cooking quality and eating quality. The cultivar is one of the main factors that could affect to the grain quality office. The aim of this work was to analyze and compare the cooking quality parameters of six different japonica varieties of rice grown in Spain （Senia, Gleva, Bahia, Maratelli, Guadiamar and Bomba）. This work focused on the study of the cooking quality of rice, because it is one of the most important factors related to grain quality in Spain. It was evaluated using five characteristics： amylose content, gel consistency, degree of spreading, gelatinization temperature and pasting parameters. The amylose content ranged from 11.60% to 21.46%, with the Gleva cultivar having the lowest amylose content and with Bomba having the highest. The gel consistency varied between 5.44 cm and 9.81 cm. Regarding the alkali test, the Maratelli cultivar had the highest dispersion and transparency. Maratelli had the lowest gelatinization temperature （61.67±0.08 ℃）, and Senia had the highest gelatinization temperature （67.05±0.02 ℃）. Finally, the pasting parameters showed significant differences among cultivars with different viscosities.     

Interactive Effects of Elevated CO2 and Temperature on Rice Planthopper,Nilaparvata lugens

It is predicted that the current atmospheric CO2 concentration will be doubled and global mean temperature will increase by 1.5-6＆#176;C by the end of this century. Although a number of studies have addressed the separate effects of CO2 and temperature on plant-insect interactions, few have concerned with their combined impacts. In the current study, a factorial experiment was carried out to examine the effect of a doubling CO2 concentration and a 3℃ temperature increase on a complete generation of the brown planthopper （Nilaparvata lugens） on rice （Oryza sativa）. Both elevated CO2 and temperature increased rice stem height and biomass of stem parts. Leaf chlorophyll content increased under elevated CO2, but only in ambient temperature treatment. Water content of stem parts was reduced under elevated temperature, but only when coupled with elevated CO2. Elevated CO2 alone increased biomass of root and elevated temperature alone enhanced leaf area and reduced ratio of root to stem parts. Brown planthopper （BPH） nymphal development was accelerated, and weight of and honeydew excretion by the F1 adults was reduced under elevated temperature only. Longevity of brachypterous females was affected by a signiifcant interaction between CO2 and temperature. At elevated temperature, CO2 had no effect on female longevity, but at ambient temperature, the females lived shorter under elevated CO2. Female fecundity was higher at elevated than at ambient temperature and higher at elevated CO2 than at ambient CO2. These results indicate that the combined effects of elevated temperature and CO2 may enhance the brown planthopper population size.     

Absorption of Food in African Pike Hepsetus odoe （Bloch, 1974） in Ado Ekiti Reservoir,Ekiti State,Southwestern Nigeria

The protein, carbohydrate and lipid contents of the food ingested and their absorption in the intestine ofHepsetus odoe in Ado-Ekiti Reservoir, Ekiti State, Nigeria were investigated. Samples were analysed chemically for protein, fat and carbohydrate using the official methods of analysis described by the Association of Official Analytical Chemist. The ingested food had mean total protein, mean total carbohydrate and mean total lipid of 60.2% - 8.55%, 15.4% ± 1.9% and 15.6% ±1.1% of the organic content respectively. Calculated mean total percentages absorbed were 72.4% protein, 52% carbohydrate and 51.5% lipid. The foregut had the highest percentage absorption while the hindgut had the lowest for all the nutrients. Different sizes of fish showed different dietary protein, carbohydrate and lipid contents. Absorptive capacity for these components of the food also varied with fish size.     

Evaluation of Essential Oils from Rosemary, Orange, Lavandula and False Yellowhead on Hatching and Motility of Root-Knot Nematode

Essential oils （EOs） from Rosemary, Rosmarinus officinalis （Lamiaceae）, Orange, Citrus sinensis （Rutaceae）, Lavandula, Lavandula angustifolia （Lamiaceae）, False Yellowhead, Dittrichia viscosa （Asteraceae） and their major components were evaluated against root knot nematode, Meloidogyne incognita and Meloidogynejavanica. Second stage juveniles＇ （J2） paralysis and egg hatch inhibition were studied, while pulverized plant parts were tested for nematodes biological cycle arrest. All EOs paralyzed J2 and M. incognita were found more sensitive than M javanica with the EC50/4 days calculated at 250, 3,650 and 4,260 12g/mL for 1）. viscosa, L. angustifolia and R. officinalis, respectively. Similarly, all EOs inhibited nematodes egg hatch and D. viscosa exhibited the highest inhibition on egg hatch （100% inhibition at 5 μg/mL）. A significant influence of constituent terpenes （limonene, 1,8-cineole, linalool, camphor, L-borneol, caryophyllene oxide, β-eudesmol） dose and exposure time was indicated on egg hatch inhibition （56% to 100% at 500 μg/mL and 1,000 μg/mL）, while only β-eudesmol achieved paralysis of J2 and specifically against M. incognita （EC50/1d = 50μg/mL）. Interestingly, the most active botanical species arresting Meloidogyne spp. biological cycle in soil was C. sinensis （EC50 = 2 mg/g） and the most sensitive nematode species was M. javanica. The larvicidal and egg hatch inhibition activity holds promise towards the optimization of artificial terpene mixtures as novel and effective natural nematicides. Complex interactions of primary compounds and subsequent decomposition derivates compose efficacy profile of soil amendments.     

体外盐酸法与母鸡体内法测定石粉溶解度的比较研究

对体外盐酸法测定的石粉溶解度与母鸡体内法测定结果进行了比较研究 体外盐酸法是在盐酸溶液浓度 0 15mol/L ,时间 5min ,振动频率 (次 /s) 1 5、1 8、2 1、2 4条件下进行的 ,8种粒度 ( 5～ 3 2mm ,3 2～ 2 5mm ,2 5～ 2mm ,2～ 1 6mm ,1 6～ 1 2 5mm ,1 2 5～ 0 4 2mm ,0 4 2～ 0 2 5mm ,<0 35mm)石粉溶解度为 :2 0 19%～ 2 3 12 % ,2 3 17%～ 2 6 0 6% ,2 5 59%～2 8 2 4 % ,2 6 2 4 %～ 2 9 74 % ,2 9 33%～ 32 83% ,31 75%～ 34 2 6% ,33 39%～ 36 0 1% ,33 5% 1～ 35 2 5% 母鸡食入石粉 3、4、5、6h后 ,8种粒度石粉溶解度结果为 :19 4 6%～2 2 71% ,2 0 52 %～ 2 5 79% ,2 6 60 %～ 2 8 66% ,2 9 72 %～ 36 0 2 % ,30 4 5%～ 4 0 0 2 % ,35 56%～ 4 4 34 % ,4 8 82 %～ 58 12 % ,54 12 %～ 66 51% 母鸡食入石粉 3h后的石粉溶解度与在振动频率 (次 /s) 1 5、1 8、2 1、2 4条件下测得的结果间有很高的相关关系 相关系数分别是 :r1=0 84 12 ,r2 =0 9359,r3=0 8754,r4 =0 8880 ,回归方程分别是 :Y1=- 2 5 90 93+1 974 9X1,Y2 =- 4 1 194 7+2 5595X2 ,Y3 =- 39 810 5+2 4 194X3,Y4 =- 4 0 1651+2 3892X4 ,(Y =体内结果 ,X =体外结果 )结果证明 :体外盐酸法测定的石粉溶?     

Probabilistic Model of the Brown Rat Control

We represent assessment of the rats control operator＇s actions, starting from the placement of rat control means （chemical, mechanical and others） in the object territory until the full its elimination and followed by assessment of the probability of rat population recovery. The probability of success is evaluated when using a combination of rat control means. We took into account changes in rat population occurring in different calendar periods of the year. The proposed calculation method can be used in training programs, as well as for the local forecast of releasing objects from rats and rats＇ re-settling.     

Influence of Cropping Systems on Soil Properties in Semi-arid Conditions of Setif, Algeria

The effects of two culture systems, conventional and no-till combined the previous crop （lentil and wheat） on soil properties were studied in the experimental site of the station Technical Institute for Field Crops （ITGC） Setif （Algeria） during the crop year 2011/2012. The results indicate that the no-till system affects positively the variables of soil properties and the organic matter has a rate of 2.89% compared to 2.44% in conventional tillage. If the conventional system has an infiltration of moisture relatively higher than that observed for no-till throughout the cycle, the no-tillage is distinguished by a higher storage of moisture at the end of cycle wheat cultivation. The results also indicate that the density （1.44 g/cm）, permeability （22.79 cm/h） and soil compaction （12.51 kg/cm） in no-till were significantly higher compared to conventional tillage 1.35 g/cm, 14.13 cm/h, 7.40 kg/cm, respectively.     

Some Engineering Properties of Sunflower Seed and Its Kernel

Some engineering properties of sunflower seed and its kernel, Shahroodi variety as a case study, were investigated at various moisture content levels （3-14% d.b.） for three size categories （large, medium and small）. With increase of moisture content from 3 to 14% d.b., all the main dimensions （length, width and thickness）, geometric mean diameter, porosity, true density, terminal velocity and static coefficient of friction increased while bulk density and rupture force for both sunflower seed and its kernel decreased for all size categories. The results showed that the highest value of static coefficient of friction for both seed and kernel was on the rubber surface, followed by plywood, polyethylene, galvanized iron, and finally aluminium surfaces. The seeds required less compressive force to dehull when loaded under the horizontal as compared to the vertical orientation. But for kernels, the trend was the opposite. Also, the compressive forces needed to initiate rupture of sunflower seed hulls were higher （47.1-94.72 N） than those required to rupture the kernel （8.5-13.4 N） in both orientations.     

Mechanical Properties of Sunflower Seed and Its Kernel,Azargol Variety as a Case Study,under Compressive Loading

The objective of this study was to investigate the effect of moisture content, size and loading orientation on mechanical properties such as force, deformation and energy absorbed per unit volume for fracturing Iranian sunflower seed and its kernel （Azargol as a case study） under quasi-static loading. Sunflower seeds and their kernels were quasi-statically loaded in horizontal and vertical orientations with moisture content in three levels： 3%, 7% and 14%, and size category in three levels： small, medium and large. The obtained results showed that rupture force for both sunflower seed and its kernel decreased with increasing moisture content while the absorbed energy and deformation at rupture point increased for all size categories in both horizontal and vertical loading orientations. Also, seeds in the vertical orientation developed hull cracks at a higher level of force than those loaded in the horizontal orientation. However, for the kernels it was the opposite. In addition, the average forces required to cause kernel rupture were lower （11.64-39.9 N） than those required to rupture the seed （30.06-117.46 N） in both orientations. Seeds loaded in a vertical orientation absorbed more energy （87.67 mJ） prior to rupture than those loaded in the horizontal （46.60 mJ） orientation. However, for the kernels it was the opposite.     

Modelling Agronomically-Suitable Sowing Date in Relation to the Risk of Frost Damage and Heat Stress of Wheat in Southern New South Wales,Australia

Sowing time of wheat in south eastern Australia varies from autumn to early winter, depending on the seasonal ＇break＇. Wheat yields are often reduced by frost damage at flowering time and by heat-and/or water-stress during grain filling. Selecting suitable varieties for specific sowing times is a complex decision farmers make because these varietal phenology and climate risks have to be assessed together. In order to help farmers make decisions, they need tools that simulate and analyse agronomically-suitable sowing dates （ASSD） for a given variety of wheat. The hypothesis underlining this study is the integration of a wheat phenology model with historical climate data is an effective approach to modelling the ASSD of current varieties used in the wheat growing areas of Southern NSW. The parameters of the wheat phenology model were based on data from five years of field experimentation across 15 sites. Data from four sites were used to examine varietal suitability in relation to sowing time and its associated risks of frost and heat damage. The optimum ASSD for any variety at 72 locations across Southern NSW was investigated. The results showed that there were substantial spatial variations in the ASSD across the target region. ASSD for a late maturing wheat genotype （EGA Gregory） can range from early March to late April, while the earliest acceptable sowing date for an early maturing spring wheat genotype （H46） can range from early to late May. The wide range of spatial variation in the earliest and latest sowing dates, as well as the varied length of sowing opportunities, highlighted the importance of being able to apply a modelling approach which can integrate information on crop phenology with climate risk for a given location. This approach would allow better decision-making on suitable varieties and sowing dates in order to minimise the risk of frost and heat damage affecting crop yield.     

Effect of Season,Location, Cultivar and Spacing on Yield and Quality of Sugarcane in Western Kenya

In Kenya almost all sugarcane grown is under rainfall conditions that are planted in different locations during both long and short rainy seasons. Effect of season, location, cultivar and spacing on yield and quality of sugarcane is not clearly understood. The research was conducted at Kibos and Mumias to determine if the yields and quality of three sugarcane cultivars were affected by season, location and row spacing. Cultivars CO 945, EAK 73-335 and KEN 83-737 were manually planted during June and September in 2011. The trial was laid out as split-split plot arranged in a randomized complete block design （RCBD） replicated three times. Data collected at harvest, 17 months after planting （MAP） including cane yields, cane yield components and cane quality. The results revealed that cane length differed significantly between June and September. Stalk population and cane yields were significantly more at Mumias compared to Kibos. Cultivar EAK 73-335 showed significantly more cane yield （t/ha） than KEN 83-737 and CO 945. Both row spacing 1.2 m and 1.5 m did not affect cane yields. Brix%, Sucrose% and Purity% differed significantly between cultivars. The relationship between cane yield and stalk population was positive and significant, which indicated stalk population is a strong determinant of cane yield. The results showed that cane yield was significantly affected by location and cane quality by cultivars. Therefore Mumias is a better zone for sugarcane cultivation for both June and September seasons compared to Kibos.     

Early Stage above Ground Interaction in Wheat-Jatropha Agrisilviculture System

Experiments were conducted to analyze the initial tree crop interaction between Jatropha curcas and wheat by planting the perennial component in East-West orientation with 8-2 m distance and wheat as intercrop at National Research Centre for Agroforestry （NRCAF）, Jhansi during July, 2007 to April, 2009. During planting of Jatropha the interaction to wheat was non-significant and influence of orientation is also nil. Eighteen months after plating Jatropha had attained the mean height of 124.56 cm, collar diameter of 6.37 cm, number of branches of 11.25, canopy diameter of 98.5 cm and yielded 18.5 g seeds per plant. During 18 MAP also observations revealed the non-significant influence of Jatropha on wheat. Observations also indicated the progress in wheat growth and yield attributes with the increase of distances from tree base and it follow the order of 0.5 m〈1.0 m〈2.0 m〈3.0, 4.0 m and open. Nearly, 62% and 14% yield loss in wheat grain was observed at 0.5 m and lm distance from the tree base respectively compare with open. Comparison ofwheat-Jatropha agrisilviculture system and sole wheat cropping indicated the net grain yield reduction up to 13.5% by agrisilviculture system. The comparison of wheat and straw yields between the two years clearly indicating that the system and sole cropping have not much differed while the influence of climatic factor is witnessed by the variation of yields over years. It revealed that the initial above ground interaction between Jatropha and wheat was due to the space that can be managed by the pruning of branches which is a recommended cultural practice of Jatropha.     

Microscopy Observations of Habitable Space in Biochar for Colonization by Fungal Hyphae From Soil

Biochar is a potential micro-environment for soil microorganisms but evidence to support this suggestion is limited. We explored imaging techniques to visualize and quantify fungal colonization of habitable spaces in a biochar made from a woody feedstock. In addition to characterization of the biochar, it was necessary to optimize preparation and observation methodologies for examining fungal colonization of the biochar. Biochar surfaces and pores were investigated using several microscopy techniques. Biochar particles were compared in soilless media and after deposition in soil. Scanning electron microscopy （SEM） observations and characterization of the biochar demonstrated structural heterogeneity within and among biochar particles. Fungal colonization in and on biochar particles was observed using light, fluorescence and electron microscopy. Fluorescent brightener RR 2200 was more effective than Calcofluor White as a hyphal stain. Biochar retrieved from soil and observed using fluorescence microscopy exhibited distinct hyphal networks on external biochar surfaces. The extent of hyphal colonization of biochar incubated in soil was much less than for biochar artificially inoculated with fungi in a soilless medium. The location of fungal hyphae was more clearly visible using SEM than with fluorescence microscopy. Observations of biochar particles colonized by hyphae from soil posed a range of difficulties including obstruction by the presence of soil particles on biochar surfaces and inside pores. Extensive hyphal colonization of the surface of the biochar in the soilless medium contrasted with limited hyphal colonization of pores within the biochar. Both visualization and quantification of hyphal colonization of surfaces and pores of biochar were restricted by two-dimensional imaging associated with uneven biochar surfaces and variable biochar pore structure. There was very little colonization ofbiochar from hyphae in the agricultural soil used in this study.     

Microbial Solubilization of Phosphorus from Nano Rock Phosphate

Phosphorus （P） is a major growth-limiting nutrient, and unlike the case of nitrogen （N）, there is no large atmospheric source that can be made biologically available. Moreover, P governs crucial role in plant as it stimulates root development and growth, gives plant rapid and vigorous start leading to better tillering and essential for many metabolic processes for seed formation. Soil microbes play very important role in bio-weathering and biodegradation. The microorganisms produce low molecular mass organic acids, which attack the phosphate structure and transform phosphorus from non-utilizable to the utilizable for the plants form. The test of the relative efficiency of isolated strains is carried out by selecting the microorganisms that are capable of producing a halo/clear zone on a plate owing to the production of organic acids into the surrounding medium. It is a well-known fact that as the particle size of rock phosphate decreases, the microbe mediated solubilization of rock phosphate increases in soil. In the present investigation, microbial solubilization of nano rock phosphate （〈 100 nm） particles was studied. Experimental results revealed that Pseudomonas striata solubilized 11.45% of the total P after 24 h of incubation from nano rock phosphate particles while 28.95% and 21.19% of the total P was solubilized by Aspergillus niger （black pigmented） and Aspergillus niger （green pigmented）, respectively. It was also observed that Aspergillus niger has the higher ability to dissolve Udaipur rock phosphate than Pseudomonas striata.