Location: Water Management Research
Title: Deep drip application and low permeability tarp on fumigant behavior in raised-bed systems for strawberry production Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 1, 2014
Publication Date: February 4, 2014
Citation: Qin, R., Gao, S., Hanson, B., Daugovish, O., Gerik, J.S., Ajwa, H. 2014. Deep drip application and low permeability tarp on fumigant behavior in raised-bed systems for strawberry production. California Plant and Soil Conference Proceedings. p. 136. Technical Abstract: High fumigant emission loss and insufficient pest control are often found in the raised-bed covered by polyethylene (PE) with shallow drip fumigation depth, which brings great challenges to strawberry growers. These dilemmas may be solved by tarping the beds with low permeability tarp such as totally impermeable film (TIF) and applying fumigant deeper. To confirm the hypothesis, a fumigation field trial was carried out in a strawberry field at Camarillo, CA by evaluating the distribution, emission, and fate of the fumigants in Pic-Clor 60 EC [a mixture of 56.7% chloropicrin (CP), 37.1% 1,3-dichloropropene (1,3-D), and 6.2% inert ingredients] as affected by application depth, application rate, and film type. The treatments included applying fumigant with full rate (25 gallon/ac) or half rate at shallow depth or at shallow plus deep depths under TIF (TIF/shallow/full; TIF/shallow/half; TIF/deep/full; TIF/deep/half), and a full rate at shallow depth under PE (PE/shallow/full), as well as without fumigant under TIF (TIF/shallow/CK). Preliminary data showed that the TIF/shallow/full had the highest fumigant concentration under film with the maximum 1,3-D and CP concentration of 7.2 and 8.7 micro-gram cm-3, respectively. The fumigant concentrations in TIF/shallow/half were also higher than those in PE/shallow/full, suggesting that TIF effectively retained fumigant and also reduced fumigant emissions in the raised-bed when compared to PE. Measurement on the TIF tarped beds showed that fumigant emissions sourced mainly from beds rather than uncovered furrows. The TIF/deep/full had much lower emissions with the peak 1,3-D and CP emission values less than 40% and 15% of the TIF/shallow/full, indicating that deep applied fumigant can further help fumigant emission reduction in TIF tarped beds. The advantage of using deep drip fumigation will be concluded upon completion of all soil fumigant and pest control data analyses.