Studies On The Phytotoxicity Symptoms Of Commonly Used Herbicides To Radish And Cabbage And The Mitigation Effects Of Some Antidotes

Herbicides are playing more and more important roles in vegetables production. At the same time, the phytotoxicities of herbicides occur continually because of improper use of herbicides and the environmental factors. Radish and cabbage are common kinds in vegetable production. Takin g radish and cabbage as test materials, phytotoxicity experiments of 67 kinds of her bicides were carried out both in the field and laboratory. The phytotoxicity symptoms and characteristics of the 67 kinds her bicides to radish and cabbage were observed. For the purpose of seeking diagnose indexes of the phytotoxicity of herbicides to radish and cabbage, the influence of 6 kinds of herbicides on antioxidant en zyme and other ind exes in radish and cabbage were determined. The mitigation effects of 8 kinds antidotes on the phytotoxicities of butralin and pendimethalin to radish were studied. The primary results are as follows:1. Studied the phytotoxicity symptoms of 67 kinds of herbicides to radish and cabbage: The results showed that herbicides of acetyl-Co A carboxylase inhibitor were safe to radish and cabbage relatively. Herbicides of cell division inhibitor and fat synthesis inhibitor caused slight phytotoxicity, there were not apparent phytotoxicity symptoms as the plants growing. Herbicides of microtubule assembly inhibitors were harmful to plant seedlings, leading to the death of seedling. Herbicides of synthetic hormones caused more apparent phytotoxicity, causing hyperplasia of root and stem, serious phytotoxicity can lead to the death of plants. Herbicides of acetyl lactic acid synthetase inhibitors, photosynthesis inhibitors, protoporphyrin oxidase inhibitors, bleaching agent, EPSP synthase inhibitors, glutamine synthetase inhibitors, DHP synthetase inhibitors caused serious phytotoxicity, eventually led to the death of plants.2. Studied the influence of 8 kinds of herbicides on antioxidant enzyme activity and other indexes of radish and cabbage: After benazolin, triclopyr, fluroxypyr, asulam, mesotrione, metamifop treatment, antioxidant enzyme activity and other indexes in radish and cabbage had different change, the trend was decrease firstly and increase subsequently. In the treatments of benazolin, triclopyr, fluroxypyr, GSH and proline changed sensitively in radish, catalase activity changed sensitively in cabbage. The determination of those indexes could estimate whether phytotoxicities of herbicide occurred preliminarily. In the treatment of asulam, the determination of MDA and soluble sugar in radish, MDA and proline in cabbage could estimate whether phytotoxicities of herbicide occurred preliminarily. In the treatment of mesotrione, the determination of peroxidase activity and proline in radish, catalase activity and superoxide dismutase in cabbage could estimate whether phytotoxicities of herbicide occurred preliminarily. In the treatment of metamifop, the determination of MDA in radish, proline and soluble sugar in cabbage could estimate whether phytotoxicities of herbicide occurred preliminarily.3. Studied the mitigation effects of 8 kinds antidotes on the phytotoxicities of butralin and pendimethalin to radish: The results showed that BR, AA, HA-K, Y-PGA had better comprehensive mitigation effects on phytotoxicity of butralin to radish, BR was the best among the antidotes. The comprehensive mitigation effects of DA-6, AA, BR, Y-PGA on phytotoxicity of pendimethalin to radish were better, DA-6 showed the best mitigation effect. Antidotes BR, HA-K, AA, Y-PGA, DA-6 demonstrated better mitigation effects on the phytotoxicities caused by the two tested herbicides butralin and pendimethalin. In the all treatment plots of the two tested herbicides(butralin and pendimethalin), HA-K had the highest yield of radish.