The Effect of Different Kind of Polyethylene Film Used as a Low Tunnel Cover on Celery Yield and Stalk Quality

Earlier experiments showed that celery could be grown under different plastic covers for spring and autumn harvest. The most significant for yield quantity and quality were light conditions. In conducted studies (2005-2007) the effect of three different covers for low tunnels: transparent, white and black film (made of original and recycled polyethylene) on the growth, yield and some quality factors of celery Tango stalks was estimated. Only small differences in the length of celery stalks grown under different films were observed. In the third year of experiment stalks grown under black film were around 1cm longer than all the others. Mean values of the yield indicate that transparent film used as a cover and the control treatment increased slightly the obtained yield but the differences did not exceed several percent. Plants grown in more favourable light conditions accumulated more dry matter as well as more soluble sugars in celery stalks. No such differences were observed under original and recycled films.