中国除草剂的发展现状及其在高粱上的应用

笔者从中国除草剂发展的现状出发,浅谈了除草剂产业面临的问题及未来发展趋势。在此基础上,综合分析了中国高粱田除草剂的应用、研究及使用现状,指出了中国高粱田除草剂在引进开发新除草剂品种的基础上,急需发展短残效品种和抗除草剂转基因作物,开发用于高粱田的除草剂混合制剂并提高使用技术,研制和应用与之相适应的环境友好型除草剂增效剂和安全剂等,改进除草剂剂型,提高高粱田除草的灵活性和选择性。     

草舒对五节芒和芦苇的除草效果初报

10.8%草舒水剂对五节芒和芦苇的除草效果试验表明,用量13 500 mL/hm2,药后45~60 d对五节芒防效达95%,持续期达184 d以上;对芦苇药后21 d防效达100%,药的持效期达85 d以上。进一步大面积应用证明,草舒除草效果良好。     

几种化学除草剂对冬油菜田的芽期除草效果研究

为筛选对油菜田芽期安全、高效、低成本的除草药剂,笔者比较了不同化学除草剂及其不同用量对防除油菜田间杂草的效果。结果表明：所用的化学除草剂对油菜无毒害作用,对油菜田的禾本科杂草和阔叶杂草的防效均在94%以上,对油菜田有增产增收的效果,增收在4340元/hm2以上,其中50%异松?乙草胺乳油1200 mL/hm2兑水1125 kg/hm2于油菜播种后进行土表喷施,除草、增产增收的效果比较好。     

不同除草剂配方组合对直播稻田抗药性杂草控制作用评价

为了明确不同除草剂配方组合防除直播稻田抗药性杂草的情况,于2009-2010年在洞庭湖稻区进行了田间试验。结果表明：处理后45天,二次使用二氯喹啉酸对稗草的株防效和鲜重防效仅分别为53.1%和65.5%,表明该稻区稗草对二氯喹啉酸已产生抗药性。两年的试验结果显示,除草剂配方组合1、2、3对抗药性稗草及其群落具有优良的防效,均在90%以上。通过两年的田间试验研究发现洞庭湖稻区稻田稗草对二氯喹啉酸已产生抗药性,试验中采用的3个除草剂配方组合在不同年份轮换使用,可避免或延缓新的抗药性杂草发生,具有良好的推广应用前景。     

An assessment of somaclonal variation as a breeding tool for generating herbicide tolerant genotypes in wheat (Triticum aestivum L.)

The present work was initiated to assess tissue culture techniques as a means of generating and selecting herbicide tolerant genotypes of wheat through exploiting somaclonal variation. Callus was initiated from immature embryos of genetically defined varieties and subcultured onto selective media containing 5 μm, 10 μm and 50 μm concentrations of difenzoquat and atrazine. Plants were regenerated from all the selective media except that media containing the highest herbicide concentration. The progenies of the regenerated plants were tested as whole plants for their response to spray application of the herbicides. For difenzoquat, variation in response from extreme susceptibility to tolerance was observed. However, genetic characterization by progeny testing tolerant lines revealed that the induced variation was not heritable. No plants tolerant to atrazine were obtained. Overall, no clear evidence of heritable mutations was obtained. Alternative strategies to obtain herbicide tolerant genotypes using cell culture techniques are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

Ability of Forage Grasses Exposed to Atrazine and Isoxaflutole to Reduce Nutrient Levels in Soils and Shallow Groundwater

Abstract

Successful implementation of vegetative buffers requires inclusion of plant species that facilitate rapid dissipation of deposited contaminants before they have a chance to be transported in surface runoff or to shallow groundwater. Thirty‐six field lysimeters with six different ground covers [bare ground, orchardgrass (Dactylis glomerata L.), tall fescue (Festuca arundinacea Schreb.), smooth bromegrass (Bromus inermis Leyss.), timothy (Phleum pratense L.), and switchgrass (Panicum virgatum L.)] were established to evaluate the ability of grasses to reduce nutrient levels in soils and shallow groundwater. Nitrate (NO₃ ^?) and orthophosphate (PO₄ ^3?) were uniformly applied to each lysimeter. In addition, half of the lysimeters received an application of atrazine, and the other half received isoxaflutole (Balance?) at levels indicative of surface runoff from cropland. The leachate from each lysimeter was collected after major rainfall events during a 25‐day period, and soil was collected from each lysimeter at the end of the 25‐day period. Water samples were analyzed for NO₃‐N and PO₄‐P, and soil samples were analyzed for NO₃‐N. Grass treatments reduced NO₃‐N levels in leachate by 74.5 to 99.7% compared to the bare ground control, but timothy was significantly less effective at reducing NO₃‐N leaching than the other grasses. Grass treatments reduced residual soil NO₃‐N levels by 40.9 to 91.2% compared to the control, with tall fescue, smooth bromegrass, and switchgrass having the lowest residual levels. Switchgrass decreased PO₄‐P leaching to the greatest extent, reducing it by 60.0 to 74.2% compared to the control. The ability of the forage grasses to reduce nutrient levels in soil or shallow groundwater were not significant between herbicide treatments. Quantification of microbial NO₃ ^? dissipation rates in soil suggested that denitrification was greatest in switchgrass, smooth bromegrass, and tall fescue treatments. The overall performance of these three grasses indicated that they are the most suitable for use in vegetative buffers because of their superior ability to dissipate soil NO₃ ^? and reduce nutrient transport to shallow groundwater.     

除草剂三元混用的增效作用评价及配方控制研究

采用３因素５水平二次通用旋转组合设计和网室微区试验方法。以剂量一杂草生长率和剂量－花生苗期生物产量为目标函数,对除草剂乳氟禾草灵、吡氟氯禾灵及精喹禾灵三元混用进行了增效作用。评价及配方控制研究,结果表明,乳氟禾草灵与吡氟氯禾灵、喹禾灵之间有增效作用。前者增效作用大于后者,吡氟氯禾灵与精喹禾灵之间为相加作用。三者混用最佳西方为：乳氟禾草灵１２．０ｇ．ｈｍ＾＿２＋吡氟氯禾灵１９．５ｇ．ｈｍＡ＾－２＋精     

除草剂对拟水狼蛛生长发育及捕食功能的影响

试验研究了苯达松、稻乐思、乙草胺、苄磺隆、神锄、金秋、艾割和果尔等除草剂对拟水狼蛛生长发育及捕食功能的影响。结果表明 :除金秋的抑制作用不明显外 ,其他几种除草剂对拟水狼蛛的抑制作用显著。对初孵狼蛛的直接杀伤力 ,果尔、稻乐思作用非常强 ,处理后 2 d狼蛛死亡率为 1 0 0 % ,乙草胺、苯达松分别为 60 %、4 0 % ,金秋、苄磺隆则无杀伤作用。多数除草剂处理 2 d后 ,拟水狼蛛捕食褐稻飞虱量有所增加 ;金秋处理 8d内 ,拟水狼蛛的捕食量显著高于对照 ,然后趋于正常。     

二苯醚类除草剂降解菌Bacillus sp. Za微生物制剂的研发与初步应用

以二苯醚类除草剂高效降解菌株Bacillus sp. Za为材料制备微生物制剂，优化液体制剂保护剂的物质配比，筛选固体制剂的最适材料，对固体制剂进行初步应用并评价其降解效果。研究结果表明：（1）液体制剂保护剂（0.20%柠檬酸钠、0.20%羧甲基纤维素、0.30% KCl）可使活菌数提高35.71%，保存30 d的液体制剂对50 mg/L乳氟禾草灵的降解率为83.50%。（2）筛选得到猪粪有机肥作为固体制剂的最适材料，保存60 d时固体制剂活菌数为8.26×108 cfu/g，对土壤中10 mg/kg乳氟禾草灵的降解率为85.52%。（3）添加固体制剂可有效缓解乳氟禾草灵残留对玉米所产生的药害。