BE521850A - - Google Patents

Description

       

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  PROCESS FOR PREPARING A SOLID AND PULVERULENT BACTERIAL CONCENTRATE.



   It is known that certain plants, more particularly legumes, directly fix nitrogen from the air through specific bacteria living in symbiosis on the roots. Providing suitable bacteria in soils that lack them is an effective measure to increase crop yields.

   This contribution can be achieved economically by inoculating the seeds with preparations containing specific bacteria and for this purpose liquid, semi-liquid or solid preparations are used so solid preparations can be used. s obtained by attaching bacteria to an absorbent substance such as peat, colloidal silica or diatomaceous earth by passing a culture of bacteria s through a layer of absorbent substance the bacteria are retained there almost completely. the drying of the filter load loaded with bacteria requires special precautions not to alter the efficiency of the bacterial culture We recommend the use of a moderate temperature, or vacuum, or both measures combined, without however being able to guarantee a complete success.



   The present invention overcomes the drawbacks of drying bacterial cultures absorbed on a filter load It is characterized by adding to a wet filter load, retaining absorbed bacteria from a liquid bacterial culture, such a quantity of dry filter load a solid, powdery product of the desired water content and bacteria concentration results.



   The example indicated below describes one of the possible applications of the invention by means of bacteria called "rhizobium", specific for the cultivation of legumes and diatomaceous earth as filter feed. - Example.



   100 liters of a culture of "rhizobium" are poured into the water containing 300,000 to 500,000 billion bacteria, prepared according to a method

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 usual and known, on the filter cloth of a vacuum filter on lacquer 1- le was distributed 1.85 kg of ground diatomaceous earth. The amount of diatomaceous earth used is determined based on the fact that it holds 1.35 times its weight in water. A single filtration is sufficient to retain almost all of the bacteria. Once the filtration is complete, the suction is still maintained for a few minutes, then the filter charge weighing 4.35 kg is collected. This is placed in a blender and mixed with 5.65 kg of freshly ground diatomaceous earth.

   10 kg of a powdered "rhizobium" concentrate containing 25% water and from 3 to 5 billion bacteria per gram are thus obtained.



   To inoculate 25 kg of seeds (ie one hectare of alfalfa), 200 g of "rhizobium" concentrate is used. The inocultation can be done by itself or by wet way. In the latter case, a suspension of the indicated amount of "rhizobium" concentrate in 2 to 3 liters of water is prepared.


    

Claims (1)

ABSTRACT. 1 Preparation of a concentrate of solid and powdery bacteria, characterized in that a wet filter charge is mixed, retaining absorbed s bacteria from a bacterial culture in liquid, with such a quantity of dry filter charge that a product of the desired water content and bacteria concentration results. 2 Solid and powdered bacteria concentrates prepared according to 1. 3 Preparation of a concentrate of "rhizobium" suitable for the cultivation of legumes according to the process described in 1. 4 Solid and powdered "rhizobium" concentrates prepared according to 1.