|Ajwa, Husein -|
|Finnimore, Steve -|
|Qin, Ruijin -|
Submitted to: International Strawberry Symposium
Publication Type: Abstract Only
Publication Acceptance Date: December 1, 2012
Publication Date: February 18, 2012
Citation: Gao, S., Ajwa, H., Finnimore, S., Qin, R. 2012. Using low permeability tarp to improve fumigation efficiency for strawberry production in California. p.137 In: Book of Abstracts, VII International Strawberry Symposium, ISHS, 18-22 Feb. 2012, Beijing, China. Technical Abstract: California (CA) produces 88% of the strawberries in USA for an economic value of approximately $2.1 billion. While the unique climate in the coastal areas of CA is favorable for high yield and high quality berry production, soil fumigation has also been essential for control of soil borne pests or diseases. The loss of methyl bromide, due to its contribution to the depletion of stratosphere ozone, has led to a shift towards the use of alternatives such as 1,3-dichloropropene and chloropicrin. As toxic and volatile organic compounds emissions of these fumigants are highly regulated. This paper reports recent findings from field research efforts to reduce emissions and improve fumigant use efficiency. Tarping has long been used for emission control and efficacy improvement in both broadcast fumigation and application to raised-beds through drip-irrigation. Film permeability and durability during field application are critical factors affecting the tarp performances. Low permeability tarp such as the totally impermeable film (TIF) has improved strawberry fruit yield and weed control while effectively controlling emissions to less than 10% of totally applied. Reducing fumigant rates under the TIF tarp is possible because the tarp improved distribution uniformity of fumigants in surface soil down to 35 cm or deeper depths and also resulted in higher concentration-time (CT) index values than standard polyethylene tarp. More field tests are needed to determine fumigation efficacy from reduced rates. The use of lower fumigant rates has multiple benefits including reduced fumigant release into the environment, reduced potential for worker and bystander exposure, shorter buffer zones, and greater likelihood that fumigant use will be available in the long-term.