Three Greenhouse Bays
The greenhouse facility was built in 2017. There are three greenhouse bays, of which the center house (shown here) is temperature controlled with a separate ventilation and filtering system (Johnson Controls). This center bay has been dedicated solely to the growth of AMF cultures since it was built, and rules to ensure that cultures are not contaminated have been established and implemented. The greenhouse utilizes Sun Blaze T5 High Output Fluorescent Lights to extend the growing period in the greenhouse into the winter months.
Aluminum benches are 3 to 4ft wide and 7 to 8 ft long, spaced about 3 ft apart. This bay is isolated from all other plant-growing areas and other plant or soil material. Unauthorized individuals are not permitted in this room without express permission from INVAM personnel. The irrigation system is an automated watering system with individual lines to each pot which further minimizes the risk of cross-contamination between cultures. Sealed concrete floors and metal benches allow us to wash all surfaces at timely intervals with a weak (5%) bleach solution. Routinely, between 120-200 cultures (pots, deepots, conetainers) are growing in this bay at any one time. At harvest, a small portion of the contents (approx. 50 mL) of each is sampled using a sterile knife, taken back to the lab, and processed to monitor for sporulation abundance, quality of spores, and any evidence of cross-contamination from other pots. Greenhouse lamps will run 14 hours each day.
Overseeding is Important
Pots and deepots are overseeded for several important reasons: (i) to minimize any bare surfaces where contaminants may be passively deposited, (ii) to minimize movement of surface particulates, and (iii) force plants to grow more slowly and to a similar height (to control lighting, detect any plant health problems, and make it easier to apply sprays).
Most cultures, regardless of pot size in which they are maintained, are grown for 4-5 months to minimize buildup of saprophytes in the growth medium and excessive senescence of roots. If grown for > 5 months, watering is carefully regulated, and plant health monitored daily.
Insect Pests are Controlled
Insect pests are controlled immediately upon detection (plants examined each day at watering time) either with soap or chemical spray. A dilute fertilizer solution is applied once, at about 4 weeks after seeding. With any symptoms suggesting presence of a soil-borne pathogen (reduced growth, chlorosis, thinning, etc.), pot contents are inspected. If any pathogen is detected (especially nematodes), the culture is immediately restarted from extracted and cleaned spores and original pot contents are autoclaved.
Cultures being dried down in the greenhouse space are isolated on a bench that is approximately 3 meters away from growth benches and are covered with a transparent plastic barrier that is sterilized with Clorox between each use.