Külvamiseks kasutatakse süviskülvi või pindkülvi tehnikat. Süviskülvi tehnika puhul pipeteeritakse vajalik kogus (nt 1 ml) proovi suspensiooni steriilse Petri tassi põhja. Eelnevalt steriliseeritud ja sulatatud agasööde temperatuuril 45 °C kuni 47 °C valatakse 15 minuti jooksul Petri tassi nii, et saadakse vähemalt 3 mm paksune söötmekiht.
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Süviskülvi tehnikat on kirjeldatud ka Tartu Ülikooli mikrobioloogia praktikumi juhendis (MIKROBP).
Mikrobioloogilise uurimise käigus tuleb: ... 1.2.3. mesofiilsete aeroobsete mikroorganismide arvu määramiseks kasutada söötme sisse külvamise tehnikat, söötme pinnale külvamist või filtrimist järgneva membraanide söötmel kasvatamisega; ...
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Sellist terminit mikrobioloogid ei kasuta. [1.02.2019]
In the pour plate technique, diluent containing the sample (typically 1 ml) is added to a sterile Petri dish. Approximately 12–15 ml of a molten (< 45 °C), tempered agar-based medium is then poured into the dish and the sample and medium are mixed. The agar is then allowed to solidify before being incubated for a specific time and temperature, depending on the type of test. During incubation, microorganisms derived from a single cell (or in some cases a clump of cells) form discrete colonies in or on the medium. These are commonly referred to as colony forming units or cfu. They are counted and the number of micro-organisms in the inoculum can be calculated.
With the pour-plate technique, the colonies form within the agar as well as on the surface of the agar medium thus providing a convenient means to count the number of viable cells in a sample.
The most frequently used techniques are the CFU counting methods (spread-plate and pour-plate techniques, and the membrane filter technique) and the end point dilution method (MPN= Most Probably Number).
