The effect of herbicides and their mixtures and weather conditions on the content of vitamin C in edible potato tubers

Abstract

The aim of the research was to determine the effect of the herbicides and their mixtures and weather conditions on the content of vitamin C in tubers of three edible potato cultivars. A field experiment was conducted from 2008 to 2010 at the Zawady Experimental Farm (52°03'N and 22°33'E) belonging to Siedlce University of Natural Sciences and Humanities. The experiment was established as a two-factorial split-plot arrangement with three replicates. The experimental factors included: I – three edible potato cultivars: ‘Cekin’, ‘Satina’ and ‘Tajfun’; II – five weed control methods: 1. mechanical weed control only – control, 2. mechanical and chemical control – mechanical control + Command 480 EC (clomazone 480 g·dm^–3), 3. mechanical and chemical control – mechanical control + Command 480 EC (clomazone 480 g·dm^–3) + Dispersion Afalon 450 SC (linuron 450 g·dm^–3), 4. mechanical and chemical control – mechanical control + Stomp 400 SC (pendimethalin 400 g·dm^–3), 5. mechanical and chemical control – mechanical control + Stomp 400 SC (pendimethalin 400 g·dm^–3) + Dispersion Afalon 450 SC (linuron 450 g·dm^–3). Research results were statistically analysed using analysis of variance. The research demonstrated that vitamin C content in potato tubers ranged from 207.5 to 215.8 mg·kg^–1 fresh matter and was significantly affected by cultivars. The examined herbicides and their mixtures significantly affected the potato tuber content of vitamin C, which increased from 3.3 to 10.4 mg·kg^–1, on average, compared with control where only mechanical control had been used. The effect of care methods on the content of vitamin C was dependent on the genetic factor. In the ‘Santina’ and ‘Tajfun’ cultivars, the highest content was obtained due to the care with herbicides Stomp 400 SC and Dispersion Afalon 450 SC, while in the ‘Cekin’ cultivar, it was the same on all objects regardless of the care used. Moreover, meteorological conditions significantly influenced the vitamin C accumulation. The lowest vitamin C content was recorded in the final study year, when the highest annual rainfall sum was accompanied by the air temperature averaging 15.6°C.