Control of Senecio vulgaris L. in carrot seed crop with pyridate tank-mixes—its potential, efficacy, and selectivity

The field experiment was conducted during the fall-spring period of the 2024/2025 growing season, at the experimental field of the Institute of Vegetable Crops Smederevska Palanka in Smederevska Palanka, Serbia. Carrot (Daucus carota L.) variety Nantes SP-80 was sown on October 2^nd 2025, after which pendimethalin at 1137.5 g ha^-1 of a.i. was applied.

Three different herbicide treatments were applied on March 24^th 2025, all including pyridate: 1) pyridate 900 g ha^-1 + clopyralid 100 g ha^-1, 2) pyridate 900 g ha^-1 + flumioxazin 30.6 g ha^-1, and 3) pyridate 900 g ha^-1 + clomazone 96 g ha^-1. All herbicides were applied with 200 L ha^-1 of water by using Lechler IDK12002 nozzles. A period of 21 days after application (DAA), crop injury, weed density, and aboveground biomass of weeds and carrots were sampled, and these were then oven-dried for 72 h at 75 ⁰C. Data was analyzed with IBM SPSS Statistics software, version 26.0, by running Tukey's test (α=0.05).

The most dominant weed species was Senecio vulgaris L. The highest dry biomass reduction of Senecio vulgaris L. was obtained in treatment with clomazone (89.09%), followed by treatments with clopyralid (55.67%) and flumioxazin (52.38%). The dry biomass reduction of carrots was highest in treatments with flumioxazin (63.53%), followed by clomazone (46.99%) and clopyralid (22.98%), respectively, whereby visual crop injury was 10, 30, and 20%, respectively. By adding flumioxazin, leaves were burned more, which is why the percent of dry biomass reduction was higher than visual rates, compared to treatments with clomazone, where, due to the synergism, visual crop injury was the highest of all three treatments.

All treatments caused crop injury, whereby flumioxazin caused the highest dry biomass reduction of carrots, but did not control Senecio vulgaris L., compared to treatment with clomazone where crop biomass reduction was less, but Senecio vulgaris L. biomass was highest.