Determination of the no observable effect level (NOEL) for four commonly used forestry herbicides on tomatoes

Abstract

No Observable Effect Levels were determined for four commonly used forestry herbicides on glasshouse grown tomatoes. For metsulfuron and glyphosate, NOELs based on visual symptoms were lower than those for dry weight production (ED5). For triclopyr the values were similar. The rates used for clopyralid/picloram mixtures allowed for a visual NOEL to be determined but were too high for the determination based on dry weight. The value of the NOEL varies with the method used to determine it.

Interaction of organosilicone surfactant concentration and spray application factors in glyphosate efficacy

“…Tomatoes (Lycopersicum esculentum cv. Russian Red) were raised and used as reported by Ray et al (1996). Both species have easily wetted, stomatous adaxial leaf surfaces.…”

“…Glyphosate, at 0.108 kg/ha, with the addition of Silwet L-77 (0, 0.1, 0.2, 0.4% v/v), was applied to tomato plants (8 replicates per treatment) using a tracksprayer (Ray et al 1996) calibrated to deliver application rates of 50, 200 and 400 litres/ha. Two different nozzles (Spraying Systems NZ) were used; a fine TX 4 ConeJet nozzle delivering droplets with a volume mean diameter (VMD) of ca 150 µm at 300 kPa, and a coarse TurboJet 11001 flat fan producing droplets with a VMD of ca 300 µm (100 kPa).…”

Effect of surfactant concentration and spray volume on retention of organosilicone sprays on wheat

“…comm.). Surfactant treatments were applied (10 replicate plants in separate pots) using a moving belt track sprayer (Ray et al 1996), at four application rates (37, 56, 127 and 280 litres/ha). A flat fan nozzle (TeeJet 8001; Spraying Systems NZ) was operated at 275 kPa, mounted 50 cm above the average plant height.…”