- Bioprecipitation
Bioprecipitation is the concept of rain-making bacteria and was proposed by David Sands from
Montana State University over 25 years ago. The formation ofice incloud s is required forsnow and mostrainfall .Dust andsoot particles can serve as ice nuclei, but biological ice nuclei are capable of catalyzing freezing at much warmer temperatures [LSU scientist finds evidence of 'rain-making' bacteria http://www.eurekalert.org/pub_releases/2008-02/lsu-lsf022808.php] . Ice-nucleating bacteria are important in cloud seeding and as plant pathogens.Cloud seeding
Many ski resorts use a commercially available freeze-dried preparation of ice-nucleating bacteria to make snow when they want [LSU scientist finds evidence of 'rain-making' bacteria http://www.eurekalert.org/pub_releases/2008-02/lsu-lsf022808.php] . This is known as
cloud seeding .Plant pathogens
Most known ice-nucleating bacteria are plant pathogens. These pathogens can cause freezing injury in plants. In the United States alone, it has been estimated that frost accounts for approximately $1 billion in crop damage each year. The ice-minus variant of P. syringae is a
mutant , lacking the gene responsible for ice-nucleating surface protein production. This lack of surface protein provides a less favorable environment for ice formation. Both strains of P. syringae occur naturally, butrecombinant DNA technology has allowed for the synthetic removal or alteration of specific genes, enabling the creation of the ice-minus strain. The introduction of an ice-minus strain of P. syringae to the surface of plants would incur competition between the strains. Should the ice-minus strain win out, the ice nucleate provided by P. syringae would no longer be present, lowering the level of frost development on plant surfaces at normal water freezing temperature (0oC) [Ice-minus bacteria http://en.wikipedia.org/wiki/Ice-minus_bacteria] .References
See also
*
Cloud seeding
*Pseudomonas syringae
*Ice-minus bacteria
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