Emission and crop response in almond orchards fumigated with reduced rates of Telone® C-35 and low permeability film for nematode control. (March 2018)

• Record Type: Journal Article
• Authors: Gao, Suduan; Doll, David A.; Qin, Ruijun; Dangi, Sadikshya R.; Gerik, James S.; Wang, Dong; Hanson, Bradley D.
• Is Part Of: Crop protection. Volume 105(2018)
• Page Start: 80
• Page End: 89
• Publication Date: 2018-03
• Subjects: 1, 3-dichloropropene -- Chloropicrin -- Concentration-time index -- Orchard replanting -- Plant-parasitic nematodes; Plants, Protection of -- Periodicals; 632.05
• DOI: 10.1016/j.cropro.2017.11.010
• Languages: English
• ISSNs: 0261-2194

Abstract

Abstract: Many high-value tree crops are dependent on soil fumigation for control of plant-parasitic nematodes and diseases for successful orchard replanting. Due to detrimental impacts on the environment, fumigants are under stringent regulations. The study investigated if a commercially available totally impermeable film (TIF) such as VaporSafe ® and reduced fumigant rates can achieve emission reduction while providing good control of plant-parasitic nematodes and improving tree establishment. Two field trials were conducted in almond orchards on a sandy soil or a sandy loam to test the effects of Telone ® C-35 (containing 63% 1, 3-dichloropropene and 35% chloropicrin) on fumigant movement, nematode survival, and tree performance. In the trials, Telone ® C-35 was applied at various rates: 100% (610 kg ha −1 ), 66%, or 33%; with three surface sealing methods: bare, standard polyethylene film (PE), and TIF. The TIF greatly reduced emissions compared to PE or bare soil with very low off-edge emissions. Both 100% and 66% rates of the fumigant promoted similar tree growth regardless of surface sealing methods. The 66% rate under TIF and PE also provided 100% control of resident nematodes as the 100% rate at or above 100 cm soil depth in both trials. Fumigation at the sandy soil site was able to reduce or eliminate the nematode population at the 120-150 cm soil depth. However, none of the treatments provided 100% control of nematodes at this depth in the sandy loam soil indicating the effects of soil texture on fumigation efficacy. Thus, TIF and reduced rates of Telone ® C-35 can be used to reduce the environmental impacts of soil fumigation and fumigant expenses. Graphical abstract: Highlights: Low permeability film resulted in low fumigant emissions. All pre-plant fumigation treatments benefited almond orchard establishment. Fumigant rate can be reduced to 66% to provide similar benefits as 100% rate. Distribution of fumigant is the key to nematode control in soil profile.