为了解决蔗田长期使用单一除草剂带来的问题,筛选高效、安全、环保的农药新品种,2013年进行了8种除草剂处理的试验研究。结果表明,玉尔好和耕杰两个药剂对杂草的茎叶处理和土壤封闭防治效果兼优,可在甘蔗上进行示范推广应用。

The weed control test of 8 herbicides in sugarcane field was conducted to select efficient, safety and environmentally friendly herbicides for solving problem of long-term using sole herbicide in sugarcane field. The results showed that effects of both Yuerhao (15%mesotrione+ 48%atrazine) and Gengjie (5%mesotrione +50%atrazine) on weed stem and leaf or soil sealing in sugarcane field were superior to the others, and they could be used for demonstration.

为了评价除草剂2,4-D对土壤生态系统的影响,采用构建人工微生态的方法,在42d内动态评估供试土壤中微生物类群的变化。结果表明:当2,4-D使用浓度为5mg/kg时,对土壤细菌及放线菌均没有显著影响,对真菌的影响也可以较快地恢复;浓度为25mg/kg和50mg/kg的处理,细菌和真菌总数均表现下降,但细菌的适应性更强;放线菌总数则表现出一定的波动性。2,4-D处理浓度越高,对真菌的抑制作用也越强。因此,建议将土壤中真菌总数作为评估除草剂2,4-D污染土壤生态环境效应的敏感指标。

In order to assess the effects of herbicide 2,4-D on soil microecological systems,the dynamic changes of soil microbial population were evaluated during 42 days incubation times by constructing manual micro-ecology.The results showed that bacteria and actinomyces were not suffered significant effects,and the influence on fungus was recovered soon when soils were treated with 5 mg/kg 2,4-D.Whenever 25 mg/kg and 50 mg/kg of 2,4-D were added to the soils,the number of bacteria and fungus was decreased, whereas the adaptability of bacteria was stronger than fungus.Meanwhile actinomyces number was risen and fallen,too.And the inhibition on fungus was increased with the higher treated concentration of 2,4-D.It suggested that fungus number could be a sensitive indicator which assessed the ecological effect of environment herbicide 2,4-D polluted.

土壤动物是土壤污染的敏感指示生物,对土壤环境变化表现出比较灵敏的反映,为了解低质量浓度除草剂对土壤生态系统的影响,进一步推动除草剂使用的安全性评价研究,采用除草剂2,4滴丁酯对土壤动物群落进行室内染毒模拟试验,参照农田施用常规参考质量浓度,设置4个质量浓度梯度和一个不喷施除草剂的对照质量浓度,质量浓度最高限于参考喷施质量浓度的3~4倍,一次染毒后分别于12、24、48和72 h后对土壤动物进行分离并对群落结构特征进行分析。试验共获得土壤动物18 655个,隶属于2门,4纲,12目,群落结构分析结果表明低质量浓度2,4滴丁酯导致土壤动物个体数和类群数有所减少,但减少的程度并不大。个体数量变化与质量浓度增高之间呈现较明显负相关(r=-0.856,P0.05),种类数变化与质量浓度之间不具有明显的相关性,土壤动物种类数的减少主要取决于稀有类群和极稀有类群,数量的变化则主要是优势类群和常见类群的增减。2,4滴丁酯的施加使得土壤动物群落多样性指数和优势度指数降低,均匀度指数增高。土壤动物个体数量和类群数量变化与染毒后经历的时间之间并未表现出明显的规律性,染毒后不同时间土壤动物优势度指数相差较大,而多样性指数和均匀度指数在不同历时时间段内相差不大。综合各分析结果能够看出,低质量浓度2,4滴丁酯处理会对土壤动物群落造成一定影响,但影响程度并不大。

As a sensitive biological indicator of soil pollution, soil animals react quickly to soil environmental changes. In order to understand the impacts of herbicides of low concentrations on soil ecosystem and promote the safe use assessment of herbicide, the experiment simulating pollution of the soil animal community with herbicide 2,4-D butyl ester was taken indoors. A concentration without herbicide as control group and 4 concentration gradients in the range of 3 to 4 times of the reference concentration were conducted on the samples at the same time. The soil animal community structures were analyzed respectively after 12 h, 24 h, 48 h and 72 h pollution. A total of 18655 soil animals, belonging to 2 phyla, 4 classes, 12 orders were captured in the test. The soil animal community structure analysis results show that the individual and group numbers of soil animals decreased in the samples of using low concentration 2,4-D butyl ester, however the reduction extent was not noticeable. Th

为筛选出有效防除大豆、玉米田野黍的除草剂,采用盆栽试验研究了4%烟嘧磺隆悬浮剂、69 g/L精唑禾草灵水乳剂、15%精吡氟禾草灵乳油、12.5%烯禾啶乳油等15种除草剂对野黍的防治效果。结果表明,在温室盆栽条件下,3种土壤处理除草剂90%乙草胺乳油、33%二甲戊灵乳油、48%异草松乳油在有效剂量1 620、1 125、1 100.25 g/hm2(推荐药量的平均药量)时,施药后40 d,对野黍的株数防效及鲜重防效均为100%。4种茎叶处理剂69 g/L精唑禾草灵水乳剂(含安全剂喷雾量3%~5%)、50 g/L精喹禾灵乳油、108 g/L高效氟吡甲禾灵乳油及12.5%烯禾啶乳油在56.93、48.75、60.75、450 g/hm2(推荐药量的平均药量)时,施药后30 d株数防效和鲜重防效均为100%。

To select effective herbicides to control Eriochloa villosa ( Thunb.) Kunth in soybean and maize fields ,a pot culture experiment was conducted using 15 herbicides .The pre-emergence herbicides ,acetochlor 90%EC,pendimethal-in 33%EC and clomazone 48%EC at doses of 1 620,1 125,and 1 100 g/hm2,respectively,provided 100%control at 40 days after spraying in greenhouse .The post-emergence herbicides ,fenoxaprop-p-ethyl 69g/L EW containing 3%~5%safener,quizalofop-p-ethyl 50 g/L EC,haloxyfop-r-methyl 108 g/L EC and sethoxydim 12.5%EC,at doses of 57,49,61,and 450 g/hm2,respectively,controlled 100%E.villosa at 30 days after spraying.

为明确30％氰草·莠去津悬乳剂与30％磺草·莠去津悬浮剂对玉米田杂草的防除效果以及在玉米不同叶龄期使用的安全性，开展了2个除草剂品种在玉米不同叶龄处理与90％莠去津水分散粒剂播后芽前土壤处理对田间杂草防效和产量影响的田间对比评价试验。结果表明，1575g a．i．/hm230％磺草·莠去津悬浮剂在玉米3～4叶期和6～7叶期施用、1350 g a．i．/hm230％氰草·莠去津悬乳剂在玉米3～4叶期施用对玉米安全，杂草防效好，玉米产量比清水对照增加10％以上，杂草防效和玉米产量均优于2160 g a．i．/hm290％莠去津水分散粒剂播后芽前土壤处理；1350 g a．i．/hm230％氰草·莠去津悬乳剂在玉米6～7叶期施用对玉米有药害，其杂草防效和玉米产量均不及2160 g a．i．/hm290％莠去津水分散粒剂播后芽前土壤处理。

The weed control efficacy and selectivity of the herbicide mixtures cyanazine · atrazine 30%SE and sulcotrione · atrazine 30%SC were compared at different growth stages of maize with the standard herbicide atrazine 90%WG applied to soil between sowing and emergence in a field experiment .Both sulcotrione · atrazine 30%SC (1 575 g a.i./hm2 ) sprayed at the 3~7 leaf stage and cyanazine · atrazine 30%SE (1 350 g a.i./hm2 ) at 3~4 leaf stage not only provided adequate weed control but also increased corn yield by more than 10%over a control treatment with only water .Their effects weed in control and yields increase were better than those of atrazine 90%WG applied to soil between sowing and emergence . Cyanazine· atrazine at the same dose,however,was not safe to maize at 6~7 leaf stage,and both weed control and crop yield were inferior ro those achieved with 2 160 g a.i./hm2 atrazine.