Methods and compositions for estimating soil microbial load

摘要

Methods and compositions for the preparation of soil samples and the determination of the number of microbes within a soil sample are disclosed. The methods include measuring, solubilizing, bleaching and filtering soil samples and measuring the turbidity of the filtered solution. The turbidity of the sample can be determined by visual inspection of a Secchi disk viewed through the column liquid sample in a transparent tubular cylinder, or by using a cell phone camera and application. Devices and kits for the rapid, cost efficient determination of microbial numbers in the field setting are disclosed. The disclosed devices and methods can also be used for applications other than determination of microbial numbers.

主权项

1. A method of determining the microbial population of a sample of soil or compost, comprising
(a) measuring a volume of the sample; (b) solubilizing microbes in the sample in a known volume of water comprising salt and/or detergent to form a microbial solution, separate from soil; (c) compensating for pigments in the microbial solution, if necessary, by adding a bleaching agent; (d) filtering the microbial solution through a filter allowing passage only of microorganisms and not soil to produce a filtrate comprising microorganisms approximately five microns in diameter or less; (e) measuring turbidity, reflectance or transmittance of the filtered microbial solution; and (f) determining the number of microbes in solution based upon the turbidity, reflectance or transmittance measurement by comparison to standard values of microbes based upon reference turbidity, reflectance or transmittance values.