转耐盐碱基因棉花生长发育及其对生物多样性的影响

为明确新型转基因棉花的生长发育、产量性状、生理生化指标及其对棉田生物多样性的影响,于2014—2015年对新型转耐盐碱基因棉花(13018)在施药和不施药条件下与其亲本对照中9807的生长发育及棉田生物多样性进行了系统调查和分析。结果表明,在棉花生长的关键时期苗期、蕾期和花铃期,无论施药与否,转耐盐碱基因棉花与亲本对照棉花间的单株叶面积、叶片干重、株高、主茎叶片数、主要生理生化物质含量均无显著差异,2种棉田中节肢动物个体总数、群落多样性指数、均匀性指数、优势集中性也均无显著差异。与亲本对照相比,在施药和不施药条件下,转耐盐碱基因棉花的单株大铃数在2014年分别增加了4.47%和12.65%,在2015年分别显著增加了59.51%和81.94%,表明转耐盐碱基因棉花较非转基因亲本棉花有较高的产量潜力。由此可见,新型转耐盐碱基因棉花在生长发育方面没有竞争优势,对棉田生物多样性无明显影响,产量构成性状在部分时期增强,具有较好的发展潜力。     

几种生物药剂对草莓蚜虫防治效果研究

本文选用了4种生物药剂对草莓蚜虫进行了田间药效试验,结果表明1.3％苦参碱水剂和0.5％藜芦碱可溶液剂在施药1d后,防效分别为67.7％和60.2％,施药7d后,防效分别达到80.3％和82.6％,而且在3次调查中,这2种药剂与化学药剂对照10％吡虫啉可湿性粉剂的防效相比均没有显著差异,可见,1.3％苦参碱水剂和0.5...     

多旋翼植保无人机喷施新烟碱类杀虫剂对蜜蜂的飘移风险

为明确植保无人机喷施新烟碱类杀虫剂对非靶标生物蜜蜂的飘移风险,在田间试验场景下,比较分析多旋翼植保无人机和背负式电动喷雾器喷施新烟碱类杀虫剂时的雾滴飘移量及对蜜蜂的影响。结果表明：应用背负式电动喷雾器和多旋翼植保无人机进行施药作业时,距离施药区下风向5 m处的雾滴飘移率分别为0.50%和23.98%;而多旋翼植保无人机施药时,即使距离施药区下风向17 m处的雾滴飘移率仍高达2.79%,且多旋翼植保无人机施药时的飘移总量显著高于背负式电动喷雾器。喷施新烟碱类杀虫剂时,应用背负式电动喷雾器作业时距离下风向5 m处的蜜蜂在施药后1 d内的死亡数量为75头,分别是距离下风向17 m处和对照组的2.4倍和1.8倍,施药后2~8 d内蜜蜂的死亡数量与对照组无明显差异;应用多旋翼植保无人机作业时距离下风向5 m处的蜜蜂在施药后1 d内的死亡数量为4 721头,分别是距离下风向17 m、29 m处和对照组的3.0倍、6.1倍和112.4倍,施药后2~8 d内蜜蜂的死亡数量明显降低,但距离施药区较近的蜜蜂其死亡数量明显高于对照组,表明多旋翼植保无人机喷施新烟碱类杀虫剂对蜜蜂存在较高的飘移风险。     

一种生物药肥对桑葚菌核病的防治效果评价

试验结果表明,使用瑞然综合型生物药肥AS 300倍液和500倍液隔7d施药1次,共施4次,可有效抑制桑葚菌核病发生,可代替其他杀菌剂在果桑上使用。     

新型生物源农药与化学农药对草莓叶螨的防效对比研究

草莓叶螨是影响北京地区草莓生产的重要害螨,本文对其进行了两种新型生物源农药(藜芦碱、多杀霉素)及化学农药(高效氯氟氰菊酯、联苯菊酯)的防效对比研究。室内毒力测定结果表明:2.5%高效氯氟氰菊酯EC和0.5%藜芦碱SL对朱砂叶螨毒力最高,其LC_(50)分别为2.54mg/L和4.18mg/L;其次是10%联苯菊酯EC和2.5%多杀霉素SC,其LC_(50)分别为13.16mg/L和84.51mg/L。田间试验结果表明:2.5%高效氯氟氰菊酯EC和0.5%藜芦碱SL对草莓叶螨防控效果最好,施药7d后防治效果达80%以上,施药14d后防治效果达82%左右,施药28d后防治效果达84%左右,持效期较长。10%联苯菊酯EC和2.5%多杀霉SC素防控效果欠佳,施药7d后的防治效果为50%左右,具有一定的防治效果;但施药14、21及28d后害虫总数有增长趋势,未表现出持续的抑制效果。与对照区相比,各药剂均表现出对草莓叶螨具有一定的防控作用。高浓度2.5%高效氯氟氰菊酯EC对草莓叶片有轻微药害,在生产中要严格控制其使用剂量;0.5%藜芦碱SL试验处理未对草莓及非靶标生物产生不良影响,安全无药害且防治效果好,在实际生产中具有良好的推广应用价值。     

间隔施药防治大豆蚜虫

大豆蚜虫Aphis glycines Matsumura是铁岭地区大豆的主要害虫之一,六十年代以来,由于田间广泛使用广谱性杀虫剂,大量天敌生物受害,致使七十年代以来蚜害日益严重。为了解决这个问题,1978至1983年我们开展了间隔施药防治大豆蚜虫试验。几年来,示范防治面积达4234亩,结果证明,间隔施药防蚜效果好,省工、省药、减少农药杀伤天敌和污染坏境,有利于恢复与保持自然生态平衡。现将结果整理如下:     

施药因子对三唑磷在水稻上残留沉积的影响

采用室内模拟试验方法,研究了施药剂量、稀释倍数、施药次数、剂型、施药时期对三唑磷在水稻上原始沉积的影响,并通过套袋处理探讨了穗期施药对糙米中三唑磷最终残留量的影响。结果表明,三唑磷的原始沉积量与施药剂量呈线性正相关关系,与稀释倍数呈线性负相关关系,线性方程分别为:y=0.883 1+0.352 7x( r=0.982 2)和y=110.21-0.200 5x(r=0.986 2),施药次数与三唑磷残留量呈正相关;于穗期施药后,未套袋处理糙米中三唑磷的残留量显著高于套袋处理。明确了田间施药过程中影响三唑磷在水稻上原始沉积量的主要因子为施药剂量、施药次数和稀释倍数,探明了套袋处理能有效降低糙米和谷壳中三唑磷的残留量,可为科学合理施药以有效降低农药残留提供参考。     

尖角突脐孢菌在温室环境下侵染稗草的致病体系研究

稗属（Echinochloa）杂草是全世界水稻等作物生产中的一类恶性杂草。人工除稗安全但费时费力，化学除稗高效但伴随农产品安全和环境相融友好方面的潜在风险。因此，寻求安全高效的除稗活性成分和施药技术成为国际上除稗剂发展的重要方向之一。在研究和开发生物除稗剂的技术体系中，满足高通量筛选安全、高效的除稗生防因子的温室检测体系是极为重要的支持平台，同样，生物除稗剂的田间科学施药技术亦应依据生防因子在稗草上致病和致害所需的最佳条件来制定。基于此，亟需探明生防因子侵染稗草致病的相关条件并建立快速有效的生防因子除稗效果温室检测体系和田间施药技术。本文系统研究了影响尖角突脐孢菌侵染稗草的相关因子，建立了稳定的温室环境下尖角突脐孢菌侵染稗草的致病体系。     

高毒农药替代防治番茄烟粉虱田间药效试验

为了了解各种试验药剂对番茄烟粉虱防治效果和施药技术,以及对非靶标有益生物的安全性,筛选出高毒农药替代产品或用药组合,为大面积推广和安全、合理使用提供依据,特进行田间农药筛选试验。     

我国施药机械与施药技术现状及对策

我国农作物病虫草鼠每年需要化学防治面积达3亿公顷次以上,使用农药100万吨(制剂)左右,喷洒这些农药最主要和最基本手段还是靠施药机械,而目前广大农民广泛使用的主要是中小型施药机械,质量普遍不高,施药技术也比较落后,农药浪费和污染严重。本文系统地介绍了目前施药机械与施药技术的现状与问题,并从实际出发,提出了新农村需要新的喷雾器这一命题,同时提出了推进施药机械与施药技术工作的对策与建议。     

Effects of different parameters on the removal of atrazine in a water environment by Aspergillus oryzae biosorption

Atrazine is the most extensively used herbicide in the agricultural and forestry sectors. Nevertheless, along with the increasing usage amount of Atrazine, its harm exposed gradually, the main problem is its residues in the environment. Microbial adsorption may effectively reduce the pollution caused by atrazine residue in the environment. In this study, a strain of fungi with the function of adsorbing atrazine was selected using microbial screening technology. According to its phenotypic characteristics and 18S rDNA gene sequencing, this strain was of the species genus Aspergillus and was named ECUST-TXZC2018. By studying the dynamic adsorption effect of this strain on atrazine, we found that this strain adsorbed atrazine after 36 hr at pH=5–7, and 20–30°C with more than 70% adsorption. These results demonstrated that ECUST-TXZC2018 had potential application ability to control atrazine residue pollution through the biosorption function.     

羧甲基壳聚糖/改性膨润土复合载体对莠去津释放和淋溶的影响

首次尝试将羧甲基壳聚糖与改性膨润土复合用作除草剂莠去津的载体,制备得到控释型颗粒剂,以延缓莠去津的释放,减少淋溶损失,提高药效及控制其污染。通过水中释放实验研究了制剂配方对莠去津释放速率的影响,并借助半经验方程探讨了其释放机理,采用土壤薄层实验考察了复合载体对降低莠去津淋溶的效果。 结果表明,采用复合载体时莠去津的半数释放时间(t 50)可达700 h 以上,比对照采用单一羧甲基壳聚糖作载体时延长了1倍以上。莠去津由颗粒剂向水相释放的过程主要受费克扩散(Fickian diffusion)控制,且经9次淋洗后莠去津的累计淋出率仅为6.0%,表明该复合载体控释制剂可显著减少莠去津对地下水的污染。     

背负式静电喷雾器静电喷施对2种玉米田除草剂的减量效应

为了明确背负式静电喷雾器静电喷施对玉米田除草剂的减量效应,以土壤处理除草剂40%乙·莠SE和茎叶处理除草剂30%苯唑草酮SC+90%莠去津WG+专用助剂作为参试除草剂,测定了背负式静电喷雾器在不同施药剂量下的静电喷施效果。结果表明:背负式静电喷雾器静电喷施对40%乙·莠SE和30%苯唑草酮SC+90%莠去津WG+专用助剂均有明显的减量效应。当40%乙·莠SE和30%苯唑草酮SC+90%莠去津WG+专用助剂中90%莠去津WG的施用量分别降至2 850 mL/hm 2和825 g/hm 2时,较各自推荐施用量分别减少用药量36.67%和21.43%,对玉米田主要杂草仍有理想的控制效果,株防效超过64%,鲜重防效超过95%;并可最大限度地改善玉米茎、穗部性状,减轻对玉米产量的影响,较人工除草分别减产1.96%和0.29%。可见,背负式静电喷雾器在玉米田土壤处理除草剂和茎叶处理除草剂喷施中具有较大的应用价值。     

2种增效剂对春玉米田除草剂的减量增效作用

为了明确2种增效剂对除草剂的减量效应,为除草剂科学减施及增效剂安全使用提供数据基础,2019年在西北荒漠绿洲生态区春玉米田,以38.5％硝·精·莠去津CS和26.7％噻隆·异噁酮SC作为茎叶处理剂,测定了激健和辉丰2种增效剂在不同施药剂量下的除草效果.结果 表明:在38.5％硝·精·莠去津CS 2310 mL/hm和2...     

Responses of Abutilon theophrasti to agricultural management systems

Seeds of Abutilon theophrasti Medic., collected from plants growing in a continuous maize or soyabean field subjected to herbicide application, cultivation or no weed management for 10 years, differed significantly in their weight and germinability. The differences in mean weight and germinability of the progeny seeds were maintained when the parent plants were grown in a greenhouse under controlled conditions. The offspring of plants with or without previous exposure to atrazine responded similarly to the herbicide in all the measurements of the growth and development of the plants, except blooms. Significant differences between the two groups of plants were mainly observed in the weight and germinability of their seeds. Although plants with or without previous exposure to atrazine usually did not differ significantly in their response to the herbicide in terms of individual traits, they differed both in the amount and pattern of overall response across all traits. The difference in overall response between plants increased with increasing rate of atrazine. It is possible that previous exposure to the herbicide had caused minor variation in a group of inter-correlated traits or in the strength or pattern of correlation among traits.     

Sulcotrione versus atrazine transport and degradation in soil columns

A soil column experiment under outdoor conditions was performed to monitor the fate of 14C-ring-labelled sulcotrione, 2-(2-chloro-4-mesylbenzoyl)cyclohexane-1,3-dione and atrazine, 6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine, in water leachates and in the ploughed horizon of a sandy loam soil. Two months after treatment, the cumulative amounts of herbicide residues leached from the soil were 14.5% and 7% of the applied radioactivity for sulcotrione and atrazine, respectively. Maximum leachate concentrations for each herbicide were observed during the first month following application: 120 and 95 microg litre(-1) for sulcotrione and atrazine respectively. After 2 weeks, 78% of the sulcotrione and atrazine was extractable from the soil, whereas after two months only 10 and 4%, respectively, could be extracted. The maximum sulcotrione content in the first 10 cm of soil was identical with that of atrazine. For both molecules, the content of non-extractable residues was low, being around 15%. Sulcotrione seems to be more mobile than atrazine but the consequences for water contamination are similar since lower doses are used.     

Photosynthetic and growth responses of zea mays L and four weed species following post-emergence treatments with mesotrione and atrazinet

We compared photosynthesis and growth of Zea mays L (corn) and four weed species, Setaria viridis (L) Beauv (green foxtail), Echinochloa crus-galli (L) Beauv (barnyardgrass), Abutilon theophrasti Medic (velvetleaf), and Amaranthus retroflexus L (redroot pigweed), following foliar applications with atrazine, mesotrione, or a combination of atrazine and mesotrione in two greenhouse experiments. Plant responses to the three herbicide treatments were compared with responses of untreated plants (control). Photosynthesis on day 14 and dry mass of Z mays was not reduced by any of the herbicide treatments. Photosynthesis and dry mass of E crus-galli, A retroflexus and A theophrasti were significantly reduced by mesotrione and atrazine alone and in combination. Photosynthesis on day 14 and dry mass of large Sviridis plants were not suppressed by either herbicide applied alone. The mesotrione plus atrazine treatment was the most effective treatment for grass weed control because plants did not regain photosynthetic capacity and had significantly lower dry mass. Shoot dry mass of broadleaf weeds was significantly reduced by all three herbicide treatments, except for A retroflexus treated with mesotrione alone.     

Removal of Atrazine Contamination in Soil and Liquid Systems Using Bioaugmentation

Reported levels of atrazine in soils at pesticide mix-load sites can vary between 7·9×10^-5 mM and 1·9 mM . We report on a mixed microbial culture, capable of degrading concentrations of atrazine in excess of 1·9 mM . At initial concentrations of 0·046 M and 0·23 M , the mixed population degraded 78% and 21% of atrazine in soil (100 days), respectively. At the same initial concentrations in liquid cultures, 90% and 56% of the atrazine was degraded (80 days), respectively. Decreased degradation in soil samples may have resulted from atrazine sorption to soil surfaces or decreased contact between the population and the herbicide. In the 0·23 M system, we attribute incomplete degradation to phosphorous depletion. Data for carbon dioxide evolution was fitted to a three-half-order regression model, but we feel that there are limitations of the application of this model to atrazine degradation. The population uses the herbicide as a nitrogen source and little carbon is incorporated into biomass, as the energy status of carbons in the ring leads to their direct evolution as [¹⁴C]carbon dioxide. This situation contributes to an evolution pattern that, when fitted to the three-half-order model, results in underestimation of the biomass produced. Data from our study suggest that our mixed culture could be used for bioremediation of atrazine at concentrations up to and exceeding those currently reported for agrochemical mixing-loading facilities. © 1997 SCI.     

Availability of atrazine to plants in different soils

The concentrations of atrazine in the shoots of wheat plants growing in 12 different soils were directly proportional to the soil solution concentrations of herbicide estimated from slurry adsorption measurements. There was a marked discrepancy between the total uptake of herbicide and the amount theoretically supplied by mass-flow in response to transpiration. This discrepancy was less when plants were grown in nutrient solutions. In an experiment with one soil only, the half-life of atrazine was 22 days and when the solution concentration in this soil was corrected for this change, a much closer prediction of atrazine uptake could be obtained. The ways in which interactions between adsorption, breakdown and transpiration rates may affect herbicide toxicity under field conditions are discussed.     

Assessment of Chemical and Manual Weed Control Approaches for Effective Weed Suppression and Maize Productivity Enhancement Under Maize-Wheat Cropping System

Effective weed management in maize-wheat (M-W) cropping systems are accountable for higher yield and plant biomass. The objective of this study was to evaluate the effectiveness of manual weeding and chemicals (pre- and post-emergence herbicide) for actual weed control to enhance maize yield and M?W system productivity. Herbicides were treated as pre-emergence (sole), post-emergence (sole) and its combined application (pre- and post-emergence) for weed eradication and suppression. Sole pre-emergence herbicide (acetyclour?+?atrazine) and sole post-emergence herbicides (nicosulfuron), and its mixed application were used in the experiments. The experiment was comprised on 6 treatments with one weedy check or control plot: W1?=?weedy check, W2?=?acetyclour?+?atrazine, W3?=?atrazine, W4?=?nicosulfuron, W5?=?nicosulfuron?+?atrazine, W6?=?acetyclour?+?atrazine?+?nicosulfuron and W7?=?manual weeding. Main weeds were Cyperus rotundus, Tribulus terrestris, Dactyloctenium aegyptium and Cynodon dactylon. Experiential findings revealed that manual weeding was found most effective in terms of controlling weed and suppression. Among the herbicides application, promising results in terms of weed destruction and suppression were shown by combined application of acetyclour?+?atrazine?+?nicosulfuron which effectively controlled weeds as compared to other treatments. It was concluded that manual weeding drastically reduced weeds frequency and biomass while among the herbicides application acetyclour?+?atrazine and nicosulfuron could be promising for weeds suppression and clamp downing as compared to all other treatments under M?W cropping system.