Phytotoxicity and uptake of chlorpyrifos in cabbage

Abstract

Chinese cabbage, Brassica chinensis L., and cabbage, Brassica oleracea L. var. capitata, are the main daily foliar vegetables of the vast majority of the population of eastern and southern China. Cabbages are also planted and consumed widely in other countries. The insecticide and acaricide chlorpyrifos is registered in many countries. Chlorpyrifos controls a variety of insects in plants and soils, and chlorpyrifos is extensively used in the Chinese market. Food poisoning due to the presence of organophosphorus pesticide residues in vegetables has been reported in China provinces. Plant uptake of pesticide residues in air, water, and soil is a source of pesticide residues in vegetables. Here, phytotoxicity and uptake of chlorpyrifos by Chinese cabbage and cabbage were studied in the laboratory using the batch technique. From 0 to 16 days after chlorpyrifos treatment, vegetables roots, stems, leaves, and culture water samples were collected, and the residues of chlorpyrifos in culture water, plant tissues were analyzed using GC-FPD. The results demonstrate that culture solutions with chlorpyrifos had no significant inhibitory effects on vegetable plant height. However, at 1.0 mg/l, it had significant inhibitory effects on the root length and fresh weight of Chinese cabbage. Then, at 10.0 mg/l, it had only significant inhibitory effects on the root length and fresh weight of cabbage compared to the control treatment. The disappearance rates of chlorpyrifos in solutions were in sequence as: nutrition solution with Chinese cabbage, nutrition solution with cabbage, pond water, nutrition solution. The results showed also that chlorpyrifos can be taken up by roots of Chinese cabbage and cabbage from water and subsequently translocated as a function of time. Uptake dynamics of chlorpyrifos from culture solutions by the two cabbage plants were similar.