The effects of the herbicide quinclorac on shoot growth in tomato is alleviated by inhibitors of ethylene biosynthesis and by the presence of an antisense construct to the 1-aminocyclopropane-1-carboxylic acid (ACC) synthase gene in transgenic plants

Abstract

Reduction of shoot growth, leaf epinasty and chlorosis in young tomato plants (Lycopersicon esculentum Mill. cv. Hellfrucht/Friihstamm) treated hydroponically with 10s7 M of the herbicide quinclorac were partially compensated when the plants were simultaneously sprayed with salicyclic acid or the oxime ether derivative PACME. Since salicyclic acid and PACME are known inhibitors of ethylene biosynthesis, it is suggested that this pathway is implicated in quinclorac action. Further support for this hypothesis was obtained in experiments with transgenic tomato plants containing an antisense gene to 1 aminocyclopropane-1 -carboxylic acid (ACC) synthase in ethylene biosynthesis. When quinclorac was applied via the root antisense plants showed reduced phenotypical alterations compared to those of wild-type plants.

Weed resistance to synthetic auxin herbicides

“…4,15 Accumulation of ethylene can inhibit photosynthesis and produce H 2 O 2 and reactive oxygen species that lead to plant death. 18,19 The presence of 2,4-D metabolites was detected in shoots and roots 48 h after application in resistant P. rhoeas populations with impaired translocation. 17 By 168 h after treatment, no 2,4-D remained and only metabolites with HPLC retention times ascribed to hydroxylated 2,3-D and 2,5-D were detected.…”

“…It appears that 2,4‐D may not reach its nuclear protein receptor complex in resistant plants resulting in repression of auxin‐responsive genes, some of which are responsible for ethylene production . Accumulation of ethylene can inhibit photosynthesis and produce H 2 O 2 and reactive oxygen species that lead to plant death …”

Uses of Plant Gene Silencing

“…. l ...carboxylate (ACe) synthase tomato plants, Grossmann and Schmulling (1995) showed ethylene biosynthesis was implicated in quinclorac action.…”

Identifying and sequencing a Mycobacterium sp. strain F4 as a potential bioremediation agent for quinclorac

“…Due to the low dosage, longevity and especially effective control of barnyard grass and certain dicot grasses, quinclorac (3,7-dichloro-8-quinoline-carboxylic acid) is widely used in rice fields [ 2 ]. The quinclorac causes the cyanide accumulation in the tissues of susceptible plants, and then eventually leads to their death [ 2 , 3 ]. The quinclorac residues are phytotoxic to many crops and vegetables.…”