The idea that microbial communities are generally beneficial to organisms has been over-sold. Just as often, microbes cause disease and degradation. To wit:


> Yeast communities built up in nectar from early to late floral stages, at which time all nectaries contained yeasts, often at densities between 104 and 105 cells/mm3. Total sugar concentration and percentage sucrose declined, and percentage fructose increased, with increasing density of yeast cells in nectar. Our results provide compelling evidence that nectar microbial communities can have detrimental effects on plants and/or pollinators via extensive nectar degradation.

> Our results provide supporting evidence by showing that nectar yeast communities can become sufficiently dense to (1) drastically alter nectar sugar composition, and perhaps more importantly, (2) compete for sugar with mutualistic consumers, reducing the nectar’s food value down to nearly zero levels.

INVISIBLE FLORAL LARCENIES: MICROBIAL COMMUNITIES DEGRADE FLORAL NECTAR OF BUMBLE BEE-POLLINATED PLANTS
CARLOS M. HERRERA, et al 2008

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html

Guidelines for posting to BEE-L can be found at:
http://honeybeeworld.com/bee-l/guidelines.htm