Sensitivity of Broccoli (Brassica oleracea var. cymosa) hybrid seedlings to selected soil applied herbicides under simulated thermoperiods and humidity of Magaliesburg

Abstract

This study was conducted under a South African controlled environment to determine the sensitivity of direct seeded broccoli hybrid to four pre-emergence herbicides at seven application rates, Metolachlor at (0.4, 0.8, 1.2, 1.6,2.0,2.4 and 2.8l/ha), Clomazone (1.0, 2.0, 3.0, 4.0, 5.0 6.0 and 7.0 ppm/ha),Oxadiazon (0.25, 0.5, 1.0, 1.5, 1.75, 2.0 and 2.5 l/ha), Halosulfuron (0.015, 0.025, 0.040, 0.055, 0.070, 0.085 and 0.1l/ha) and an untreated non-herbicide control, which was demonstrated using RBCD and replicated three times in a greenhouse pot experiment between June and September 2017.Clomazone and Metolachlor herbicides caused unacceptable injury (greater than 25%) at the proposed dose of each herbicide applied at 7, 14, and 21 DAT.Oxadiazon at 7 and14 DAP caused a greater visual injury and also reduced plant vigor by 50%.Halosulfuron caused a 10% visual injury. Broccoli hybrid was tolerant to halosulfuron at 0.055 and 0.070l/ha.

Lolu cwaningo lwenziwe ngaphansi kwemvelo elawulwayo yaseNingizimu Afrika ukuze kutholwe ukuzwela kwehybrid ye-broccoli enembewu eqondile emithini yokubulala ukhula emine ngaphambi kokuhluma ngezilinganiso zokufaka eziyisikhombisa, i-Metolachlor ku-(0.4, 0.8, 1.2, 1.6,2.0,2.4 kanye no-2.8l/ha), I-Clomazone (1.0, 2.0, 3.0, 4.0, 5.0 6.0 kanye no-7.0 ppm/ha), i-Oxadiazon (0.25, 0.5, 1.0, 1.5, 1.75, 2.0 kanye no-2.5 l/ha), i-Halo1025, 0.05, 0.0, 0.0, 0. , 0.085 kanye no-0.1l/ha) kanye nokulawula okungalashiwe okungabulali ukhula, okuboniswe kusetshenziswa i-RBCD futhi kwaphindaphindwa kathathu ocwaningweni lwebhodwe elibamba ukushisa phakathi kukaJuni noSepthemba 2017. Imithi yokubulala ukhula ye-Clomazone ne-Metolachlor idale ukulimala okungamukeleki (okungaphezu kuka-25%) umthamo ohlongozwayo womuthi ngamunye osetshenziswa ku-7, 14, kanye no-21 DAT.I-Oxadiazon ku-7 kanye ne-14 DAP ibangele ukulimala okubonakalayo okukhulu futhi yanciphisa amandla esitshalo ngo-50%.I-Halosulfuron ibangele ukulimala kokubona okungu-10%. 0.070l/ha.

Hierdiestudie is uitgevoeronder 'n Suid-Afrikaanse beheerde omgewing om die sensitiwiteit van direktesaad broccoli-baster vir viervoor-opkoms onkruiddoders te bepaal teen sewe toedieningshoeveelhede, Metolachlor by (0.4, 0.8, 1.2, 1.6, 2.0, 2.4 en 2.8l/ ha) Clomazone (1.0, 2.0, 3.0, 4.0, 5,0 6,0 en 7,0 dpm/ha), Oxadiazon (0.25, 0.5, 1.0, 1.5, 1.75, 2.0 en 2.5 l / ha) Halosulfuron (0.015, 0,025, 0,040, 0,055, 0,070, 0,085 en 0,1l/ha) en 'n onbehandelde beheerkontrole, wat met RBCD gedemonstreer is en drie keer herhaal is in 'n kweekhuispot-eksperiment tussen Junie en September 2017. Clomazoneen Metolachlor onkruiddoders het onaanvaarbare skade veroorsaak (meer as 25%) teen die voorgestelde dosis van elke onkruiddoder toegedien op 7, 14, en 21 DNP. Oxadiazon teen 7 en14 DNP het 'n groter visuele skade veroorsaaken die plantkrag met 50% verminder. Halosulfuron het 'n 10% visuele skade veroorsaak. Broccoli-baster was verdraagsaam tot Halosulfuron by 0,055 en 0,070l/ha.