The loss of methyl bromide (MB) as a soil fumigant has created the need for new weed management systems for crops such as strawberry (Fragaria ×ananassa Duchesne). Potential alternative chemicals to replace methyl bromide fumigation include 1,3-D, chloropicrin (CP), and metam sodium. Application of emulsified formulations of these fumigants through the drip irrigation system is being tested as an alternative to the standard shank injection method of fumigant application in strawberry production. The goal of this research was to evaluate the weed control efficacy of alternative fumigants applied through the drip irrigation system and by shank injection. The fumigant 1,3-D in a mixture with CP was drip-applied as InLine (60% 1,3-D plus 32% CP) at 236 and 393 L·ha-1 or shank injected as Telone C35 (62% 1,3-D plus 35% CP) at 374 L·ha-1. Chloropicrin (CP EC, 95%) was drip-applied singly at 130 and 200 L·ha-1 or shank injected (CP, 99%) at 317 kg·ha-1. Vapam HL (metam sodium 42%) was drip-applied singly at 420 and 700 L·ha-1. InLine was drip-applied at 236 and 393 L·ha-1, and then 6 d later followed by (fb) drip-applied Vapam HL at 420 and 700 L·ha-1, respectively. CP EC was drip-applied simultaneously with Vapam HL at 130 plus 420 L·ha-1 and as a sequential application at 200 fb 420 L·ha-1, respectively. Results were compared to the commercial standard, MB : CP mixture (67:33) shank-applied at 425 kg·ha-1 and the untreated control. Chloropicrin EC at 200 L·ha-1 and InLine at 236 to 393 L·ha-1 each applied singly controlled weeds as well as MB : CP at 425 kg·ha-1. Application of these fumigants through the drip irrigation systems provided equal or better weed control than equivalent rates applied by shank injection. InLine and CP EC efficacy on little mallow (Malva parviflora L.) or prostrate knotweed (Polygonum aviculare L.) seed buried at the center of the bed did not differ from MB : CP. However, the percentage of weed seed survival at the edge of the bed was often higher in the drip-applied treatments than in the shank-applied treatments, possibly due to the close proximity of the shank-injected fumigant to the edge of the bed. Vapam HL was generally less effective than MB : CP on the native weed population or on weed seed. The use of Vapam HL in combination with InLine or CP EC did not provide additional weed control benefit. Chemical names used: 1,3-dichloropropene (1,3-D); sodium N-methyldithiocarbamate (metam sodium); methyl bromide; trichloro-nitromethane (chloropicrin).
activated in the soil by sprinkler irrigation according to label directions ( CDMS, 2006 ). Weed control assessments. Weed control was assessed by three methods: 1) weed seed viability bioassays; 2) weed density counts; and 3) timing of handweeding
.4.4. (RStudio, Boston, MA). Pathogen densities, weed seed viability, tuber germination, weed density data, and strawberry yield data were analyzed using an analysis of variance (fixed effect model III, α = 0.05). Adjunct Fisher’s least significant difference
over the growing season, and the fresh shoot and root biomass of the harvested weeds was recorded. V. dahliae control. In 2008–2009, in addition to weed seed viability, the effect of treatments on V. dahliae control was assessed. Soil samples
and June 2016 and two tests on weed seed viability during June 2018 and 2019 at Salinas, CA. The experimental units were 24 microplots (1 m 2 ) for all four studies. The Mar. and June 2016 and June 2018 experiments were located at the U.S. Department
number of microsclerotia was also included to ensure that the technique provided consistent results. Treatment effect on weed seed viability was evaluated in both calla lily trials. Twenty-five seeds of common chickweed ( Stellaria media ), common
seasons. Dates of yellow nutsedge and weed seed burial and retrieval as well as hand weeding and weed biomass collection dates are listed in Table 1 . Statistical analysis. For the weed seed viability data, the season × location interaction was not
.1002/ps.728 Shrestha, A. Browne, G.T. Lampinen, B.D. Schneider, S.M. Simon, L. Trout, T.J. 2008 Perennial crop nurseries treated with methyl bromide and alternative fumigants: Effects on weed seed viability weed densities, and time required for hand
ideal and desirable ranges for compost typically sold in the horticultural industry ( Table 1 ). In addition, heavy-metal content did not exceed normal ranges. The compost samples were free of weed seeds, viable plant propagules of any species and
arrangement J. Amer. Soc. Hort. Sci. 1899 1902 Mashingaidze, A.B. Chivinge, O.A. Zishiri, C. 1996 The effect of clear and black plastic mulch on soil temperature, weed seed viability and seedling emergence, growth and yield of tomatoes J. Appl. Sci. South. Afr