Agriculture & soil science.

 Common sampling tools and accessories  Clean Plastic or glass bottle of 500 ml capacity . cotton or nylon thread . water table recorder. Glass marking pencil . labels and tags Sample collection procedure. The container must be thoroughly clean before the use. Bottle  should be rinsed 3 to 4 time with water from which the sample is drawn . care should be taken to collect sample only after continuous discharge of the source for 10 to 20 minute . if the source of irrigation water is tank channel or river  the sample should be drawn either away from the sides or from the mid stream.  the tubewell and hand pump are to be Run for about 10 to 20 minut prior to the sampling and for open well several buckets of water have to be thrown out first . About half litre of the sample is quite sufficient.  the water sample after labelling must be send laboratory immediately for testing in order to avoid any change or deterioration in its quality due to the chemical microbi...

TITLE  - Determination of available boron in given soil. Method - 1) Azomethine H 2) Hot water extraction method. Scientists - burger and truog (1939)  Reagents - Azomethine H - Dissolved 0.45 gram Azomethine H and one gram ascorbic acid in hundred ml distilled water Buffer solutions - Dissolved  250 gram ammonium acetate and 15 gram EDTA (disodium salt) in 400ml distilled water then add 125/8 Glacial acetic acid slowly. Calcium carbonate solutions - 0.01 M Dissolved 1.11 gram calcium chloride in 900ml distilled water and make the volume of one litre.                                                                                                  PROCEDURE - Extraction   - take 20 grams soil sample in conical f...

 TITLE  -  Determination of available Phosphorus in soil.   Method  -  Acid soil - Bray's method.  Alkaline soil - olsen method.  Regents .- 1) 0.5 ml NaHco3 (PH = 8.5 ) - Dissolved 21 gram sodium bicarbonate in 450 ml water adjust the pH 8.5 and make up the volume up to 500 ml . 2) Activated charcoal  3) solution 'A' - a) Dissolved 12 gram ammonium molybdate in 250 - 300 ml distilled water . b ) Dissolved 0.291 gram antimony potassium tartrate in 100 ml distilled water.  c) 5 normality - H2 s o4  Dissolved 140 ML concentrated H2 S o4 in 1000 ml water  . Solution 'A'- Add cool ammonium molybate in normal H2 s o4 solution followed by cool antimony potassium tartrate and volume is made up upto 2 litre  . Solution 'B'- Dissolve 1.056 gram ascorbic acid in 200 ml of solution 'A'. solution B should be prepared fresh.  0.25% - 2.4 paranitrophenol. -  Dissolved 0.25 gram 2.4 para-nitrophenol in hundred gram distilled wa...

TITLE - Detemination of available potassium from soil.  REAGENTS  -  1) Neutral ammonium acetate - Dissolved 77.1 gram ammonium acetate 900 ml water & adjust the pH to 7 by Acetic Acid or Ammonium hydroxide dilute to 1 litre. 2) preparation of standad solution.- Dissolved 1.908 gram KCL in distal water. And makeup the final volume one litre. this solution called as stock solution. 3)  Preparation working solution. - Take 10 ml solution from stock solution and makeup volume 100 ml. 4) Preparation of standard series - Prepare 0 2 4 6 8 10 ml of working solution **** PROCEDURES  - 1) Take 5 gram of soil in conical flask. 2) Add 25 ml of neutral normal            ammonium acetate.  3) Shake for 5 minut. 4) Filter the content.  5) Take reading on flame photometer. GRAPH FACTOR Graph factor reading            Flame Concentration.                  ...

TITLE  - Determination of available nitrogen  in the soil. METHOD - Alkaline permagnate. Scientists : Subbiah and asijo 1956. Principle - the organic matter in the soil is oxidized by Kmno4 in presence of NaoH. The ammonia released during oxidation is absorbed in boric acid to convert the ammonia to ammonia borate. The ammonia borate formed is titrated with standard H2So4 from the volume of standard H2So4 required for reaction with ammonium borate.The Nitrogen is calculated.   REAGENTS   -  1) Potassium   permagnate Kmno4 (0.32%).- Dissolve 3.2 gram potassium permagnet in one litre of distilled water with the intermittent shaking till it completely dissolved. store in umbrella colour bottle and keep it in the dark.  2)Sodium hydroxide solution NaoH (2.5%)- Dissolve 25gm of pure sodium hydroxide in 1 litre of distilled water. 3) Boric acid H3Bo3 (2%)  Dissolve 20 gram of boric acid AR grade in 800ml distil water by heating to content cool...

TITLE :- Determination of organic carbon in soil by walkley & black method.  Principle -   The organic carbon in organic matter is oxidised by known excess of chromic acid .(K2 cr2 O7 + H2 s o4). The excess acid chromic acid not reduced by organic matter is determined by Black titration which standard feso4 solution (redox titration) using ferroin indicator. the organic in soil calculated from the chromic acid utilised (reduced by it) Reagent  Potassium dichromate solutions,  Dissolve 49.04gm of dried reagents grade potassium dichromate, K2cr2O7 in distilled water & dilute it to one liter.  Ferrous sulphate solutions 0.5N Dissolve 139gm of reagent grade ferrous sulphate feso4. 7H2o in distilled  water and add 15ml of concentrated H2so4 cool and dilute to one litters or dissolve 196.19gm ferrous  ammonium sulphate feso4(NH4)so4.6H2o and making up-to one litters standardized the solution against potassium add 20 ml concentrated H2so4, before...

TITLE-  DETERMINATION OF CALCIUM CARBONATE (Caco3) of soil.  Principle  The soil is titrate  with known extended of standards hydrochloric acid to neutralize all carbonate and excess Hcl acid is back titrate with NaoH using phenolphthalein indicator . The calcium carbonate equivalent is calculate by the volume of standard Hcl required for neutralization. RAPID TITRATION METHOD -  REAGENT  0.5 N Hcl :dissolve 44.5ml Hcl in 1L of water.  0.25 N NaoH:dissolved 10gm NaoH in 1 L of water.  Phenolphthalein indicator.  PROCEDURE  Take 5gm soil in 250 ml conical flask.  Add 100 ml 0.5 N Hcl. Stir & keep for 1 hours.  Allow it to settle  & filter.  Take 10 ml filtrate into another conical flask.  Add 3 to 5 drops of phenolphthalein Indicators.  Titrate it against of 0.25 N NaoH still the color changes to pink. (A) note reading.  Run the blank. (B) note reading.  OBSERVATION  B - blank sample re...