A SYSTEM AND METHODOLOGY FOR MEASURING VOLATILE ORGANIC-COMPOUNDS PRODUCED BY HYDROPONIC LETTUCE IN A CONTROLLED ENVIRONMENT

A system and methodology were developed for the nondestructive qualita tive and quantitative analysis of volatile emissions from hydroponical ly grown 'Waldmann's Green' leaf lettuce (Lactuca sativa L.). Photosyn thetic photon flux (PPF), photoperiod, and temperature were automatica lly controlled and monitored in a growth chamber modified for the coll ection of plant volatiles. The lipoxygenase pathway products (Z)-3-hex enol, (Z)-3-hexenol, and (Z)-3-hexenyl acetate were emitted by lettuce plants after the transition from the light period to the dark period, The volatile collection system developed in this study enabled measur ements of volatiles emitted by intact plants, from planting to harvest , under controlled environmental conditions.