加拿大一枝黄花种子在不同介质中的萌发及其药剂防除

为探明加拿大一枝黄花作为杂草对农田的危害性,以氯化铵、硫酸铵和尿素溶液及土壤浸出液为介质进行加拿大一枝黄花种子萌发试验,用扑草净、乙草胺、环嗪酮、果尔和氯磺隆等5种除草剂进行萌发前除草剂处理对加拿大一枝黄花的防除试验,以农达和环嗪酮进行茎叶除草剂处理防除加拿大一枝黄花的田间试验。结果表明:加拿大一枝黄花种子在0.05%和0.20%尿素介质中的萌发率显著低于清水对照(显著水平分别达0.01和0.05),在其它介质中其萌发率与对照无显著差异;种子萌发前除草剂处理后30 d,扑草净等5种除草剂各剂量处理的鲜重防效均达到97%以上,扑草净、乙草胺和环嗪酮各剂量处理、果尔每667 m220 m l和25 m l处理、氯磺隆每667 m22.0 g处理的株防效都在90%以上;在田间对加拿大一枝黄花茎叶喷施除草剂后60 d,农达和环嗪酮各剂量处理的防效达94.44%~100.00%,处理后100 d,环嗪酮各剂量处理的防效仍达91.11%~98.89%,而农达的防效则降至80.00%。可见,农田土壤中的氮素不利于加拿大一枝黄花种子的萌发,现有除草剂也可对其进行有效的防除。

Germination of Canadian Goldenrod (Solidago canadensis L.)Seed in Different Nutrient Media and Its Herbicidal Control

To find out the harmfulness of weed Canadian goldenrod to farmland,a series of experiments were carried out in the lab and field.Seed germination experiment was conducted by putting seeds into four media,ammonium choloride,ammonium sulfate,urea and soil lixivium.Control efficacy of pre-germination treatment of five herbicides,prometryn,acetochlor,hexazinone,oxyfluorfen and cholrsufuron, were compared.And control efficacy of herbicides Roundup and hexazinone which were sprayed to the plants of Canadian goldenrod in the field were also recorded.Results indicated that the germination percentages of Canadian goldenrod seeds in the media of 0.05% urea and 0.20% urea were much lower than that in water(control)(P<0.01 and P<0.05,respectively),while no significant difference was found out between other media treatment and water.On the 30th day after pre-germination treatment,control efficacy on fresh weight of all five herbicides at different dosages was more than 97%,while efficacy on plant number in the treatment of prometryn,acetochlor,hexazinone,20 ml and 25 ml oxyfluorfen per 667 m~2,2.0 g chlorsulfuron per 667 m~2 reached 90%.After spraying herbicides on Canadian goldenrod plants for 60 d,the efficacy of Roundup and hexazinone ranged from 94.44% to 100.00%.Even after spraying for 100 d,the efficacy of hexazinone was still high at 91.11% to 98.89% at different dosages.Thus,it could be inferred that nitrogen did not favor the seed germination of Canadian goldenrod and Canadian goldenrod could not harm the farmland to a high degree due to the effective control of existing herbicides.