Field trials were conducted to determine the effect of fumigant-pebulate combinations on purple nutsedge density in fresh market tomato. Treatments consisted of methyl bromide plus chloropicrin (MBr plus Pic) [67:33] at rates of 270 and 130 kg/ha, respectively; Pic plus pebulate at 400 and 4.5 kg/ha, respectively; metham (MNa) plus pebulate at 485 and 4.5 kg/ha, respectively; dazomet plus pebulate at 950 and 4.5 kg/ha, respectively; and 1,3-dicholopropene plus Pic (C-17) [87:13] plus pebulate at 392 and 4.5 kg/ha, respectively. At 12 wk after treatment, MBr plus Pic controlled purple nutsedge more effectively (10 plants/m2) than the fumigant-pebulate combinations (50 to 70 plants/m2). Compared to MBr plus Pic, Pic plus pebulate had a 14% lower marketable yield. No differences in marketable yield were noted with dazomet plus pebulate or C-17 plus pebulate compared to MBr plus Pic. However, MNa plus pebulate produced a 15% higher yield than MBr plus Pic. Additionally, MNa plus pebulate had 15% higher marketable fruit weight than MBr plus Pic.
Nomenclature: Purple nutsedge, Cyperus rotundus L. #3 CYPRO; tomato, Lycopersicon esculentum Mill. ‘Sunny’.
Additional index words: Methyl bromide, chloropicrin, metham, dazomet, 1,3-dichloropropene.
Abbreviations: MBr, methyl bromide; MNa, metham; 1,3-D, 1,3-dichloropropene; Pic, chloropicrin; C-17, 1,3-D plus Pic (87:13); MITC, methylisothiocyanate; WAT, weeks after treatment.