A new Plant and Soil Sciences greenhouse was completed in 2012. With dismantling of the small greenhouse attached to South Agricultural Sciences, INVAM was assigned a bay for exclusive use. After some modifications to optimize culture productivity and sanitation, we moved into this space in January, 2014. It was a much better environment because we had complete control of temperature (90°F during the day and 70°F at night) and 600 Watt high-pressure sodium vapor lamps that supplemented natural sunlight and extended the day length to 14 hours throughout the year. Moreover, operational rules were put in place for all greenhouse spaces to ensure global cleanliness and facilitate routine monitoring for common greenhouse pests (aphids, white flies, thrips).
Rotatable aluminum benches are 5 ft wide and 8 ft long, with plenty of room to move around on all sides. A stainless steel sink is situated between two of the tables for handling of cultures before being transported to South Agricultural Sciences for processing and/or drying. This bay is isolated from all other plant-growing areas and other plant or soil material or unauthorized individuals are permitted in this room without express permission from INVAM personnel and the greenhouse manager culture development and maintenance. The space affords excellent control of watering regime, quality control and for close monitoring of biotic and abiotic contaminants that might be introduced serendipitously.
Sealed concrete floors and metal benches allow us to wash all surfaces at timely intervals with a weak (5%) bleach solution. Although we are capable of setting up an automated watering system, we have chosen not to do this because pots are not uniform in volume and mechanical failure would put many cultures at risk. Therefore, watering is done manually every day with great care to minimize any chance of cross-contamination between pots. The benefit of daily watering is that any changes to plant health, insect introductions, or any other visible problem can be detected quickly and resolved before the incident becomes serious.Routinely, between 120-200 cultures (pots, deepots, conetainers) are growing in this bay at any one time. When cultures are 3-4 months old (one month before harvest), a small portion of the contents (approx. 50 mL) of each is sampled at the sink using a sterile knife, taken back to the lab, and processed to monitor for sporulation abundance, colonization, quality of spores, and any evidence of cross-contamination from other pots.