7种土壤处理除草剂对冬小麦田杂草的防治效果

为了探明7种除草剂土壤喷雾施药对冬小麦田一年生杂草的防治效果与对冬小麦的安全性,参照《农药田间药效试验准则》相应方法于田间比较了施药前浇水与施药后浇水两种模式下防效与安全性的差异。结果表明,药剂在施药后浇水处理模式下对杂草总体的防效优于施药前浇水处理模式;试验剂量下,施药后浇水模式中氟噻草胺药后150天对猪殃殃、播娘蒿、看麦娘3种杂草的总体株数防效和鲜重防效均高于95%,噁草酮有效量720 g/hm²处理对播娘蒿、看麦娘的鲜重防效高于95%,对猪殃殃的鲜重防效则高于85%。从安全性、防效及除草剂减量角度综合分析,推荐在小麦田使用氟噻草胺和噁草酮进行土壤封闭处理,一次施药即有理想的防除效果。     

苄嘧磺隆·氟吡磺隆WG对机插秧稻田杂草的防控效果及安全性探析

为了验证14.2％苄嘧磺隆·氟吡磺隆WG对机插秧稻田杂草的防控效果,在水稻机插秧10 d后进行小区试验,施药方法为甩施.14.2％苄嘧磺隆·氟吡磺隆WG施药后15d,对杂草有较高的防控效果,杂草总株防效为80.69％～88.08％,显著高于对照药剂,且对水稻幼苗安全.施药后30d,总株防效分别为86.48％～90.56...     

邵阳市植烟田杂草种类分析及防控研究

旨在有效防控邵阳市植烟田杂草,维护大田烟草健康生长,调查了植烟田的杂草种类并归纳分析,在前期优选除草剂混配（乙羧氟草醚+砜嘧磺隆）基础上,通过施药后30 d除草效果调查,验证自制助剂的增效作用。结果表明,邵阳市植烟田杂草共有42种,隶属于22科,广泛分布于各植烟田。自制助剂混配除草药剂有较好的除草效果,施药后30 d,砜嘧磺隆+乙羧氟草醚+助剂3000倍液总株防效95.44%,总鲜重防效达到97.19%,且对烟草安全。供试自制助剂+除草剂可以减施增效,可为烟草杂草的有效防控提供参考。     

农药使用与植保技术问与答

<正>问:施用异丙隆加甲基二磺隆防除看麦娘属类杂草效果也不好,那么用什么药防除效果好?答:异丙隆对看麦娘和日本看麦娘等禾本科杂草有良好防效,草龄大时需适当增加用药量才能保证防效。甲基二磺隆对这两种禾本科杂草有良好防效,但近年来部分地区对看麦娘产生了抗性,导致防效下降。如用异丙隆加甲基二磺隆防除看麦娘和日本看麦娘效果差,可能是草龄较大、用药量偏少、施药不均匀、杂草抗性强等原因。防除小麦田看麦娘和日本看麦娘,除异     

24种除草剂对空心莲子草的生物活性

采用温室盆栽法,评价了24种除草剂对空心莲子草的防治效果,并对防效较好的药剂进行了室内毒力测定。结果表明,在田间推荐剂量下,有17种药剂对空心莲子草的防效较好,鲜重防效>80.0%。氯氟吡氧乙酸对空心莲子草的室内毒力最高,为20.07 g a.i./ha,草甘膦的最低,为560.79 g a.i./ha,17种药剂的室内毒力由高到低的顺序为：氯氟吡氧乙酸>丙炔氟草胺>苯磺隆>乙氧氟草醚>嗪草酮>麦草畏>氟磺胺草醚>2,4-滴丁酯>硝磺草酮>百草枯>三氟羧草醚>噁草酮>乳氟禾草灵>异丙隆>2甲4氯钠>乙羧氟草醚>草甘膦。综合考虑药剂特性,并对比药剂的田间推荐剂量,氯氟吡氧乙酸、丙炔氟草胺、苯磺隆、乙氧氟草醚、嗪草酮、麦草畏、氟磺胺草醚、2,4-滴丁酯、硝磺草酮、百草枯、三氟羧草醚、异丙隆、2甲4氯钠、草甘膦均可用于田间防除空心莲子草,其中,苯磺隆使用剂量应略高于田间推荐量,其它药剂在田间推荐剂量下即可达到理想的除草效果。     

农药使用与植保技术问与答

<正>问:能否用炔草酯加异丙隆防除小麦田杂草?答:根据小麦田杂草种类、大小等合理混用药除草。炔草酯和异丙隆混用能防除小麦田大部分种类的禾本科杂草,对部分种类的阔叶杂草也有一定的防效。近年来菵草、硬草、日本看麦娘等禾本科杂草已对炔草酯产生较强抗性,用药防除效果差,在杂草抗性强的地区施用这两种药对这些杂草的防效不能保证。炔草酯在低温期施用对麦苗的安全性相对较高,但也应避免在施药后短期内出现强降温低温霜冻天气。     

麦田雀麦有药除

正5%唑啉草酯乳油对菵草、野燕麦、狗尾草、硬草、看麦娘、日本看麦娘、棒头草、黑麦草等禾本科杂草有较好的防效,对雀麦、早熟禾、节节麦的防效较差或无防效。小麦田常用禾本科杂草除草剂精噁唑禾草灵、炔草酯对雀麦的防效也很差。啶磺草胺、甲基二磺隆、氟唑磺隆对雀麦防效较好,雀麦发生重的小麦田可以因地制宜选用这些药除草。异丙隆对低龄期雀麦也有较好防效,对大龄草防效差,将异丙隆与上述药混用,能提高对雀麦等杂草的防效。     

冀中南谷田杂草发生与除草剂筛选试验

以冀中南谷田杂草为对象,探讨了谷田杂草的发生规律与除草剂筛选试验。结果表明:不同播期的谷田杂草种类基本一致。春播谷田杂草发生有3个峰期,5月中旬以双子叶杂草为主,6~7月份以单子叶杂草为主;夏播谷田杂草发生仅1个峰期,主要在7月上中旬,以单子叶杂草为主。化学防除以44%谷友WP剂量1800g/hm²为最佳,药效明显高于10%单嘧磺隆WP、50%扑灭津WP与2,4-D丁酯EC;春播谷田施药后79d对单、双子叶杂草的株数防效与鲜重抑制率分别为49.19%、96.76%与96.01%、96.03%。夏播谷田在施药后55d对单、双子叶杂草的株数防效与鲜重抑制率分别为41.13%、92.34%与93.39%、98.15%。     

谷子和杂草对氰氟草酯的敏感性

通过室内生物测定试验和田间小区试验,明确氰氟草酯对谷子的安全性和杂草的敏感性,为氰氟草酯在谷田的应用提供理论依据。室内生物测定试验结果表明,谷田恶性杂草牛筋草和谷莠子对氰氟草酯分别为高度敏感（GR₉₀ 45.02g a.i./hm²）和一般敏感（GR₉₀ 124.13g a.i./hm²）。氰氟草酯对冀谷39和杂草的选择性指数大于2,且为不敏感（GR₁₀ 284.05g a.i./hm²）,对豫谷18和杂草的选择性指数小于1,且为高度敏感（GR₁₀ 13.70g a.i./hm²）。冀谷39的抗药性指数为9.65。田间试验结果进一步表明,氰氟草酯能有效防除抗除草剂谷子品种冀谷39田间的禾本科杂草,对牛筋草和马唐的防效高,氰氟草酯在110g a.i./hm²剂量下对牛筋草和马唐的鲜重防效和株数防效均高于96%;氰氟草酯对谷莠子生长有显著抑制作用,110g a.i./hm²剂量对谷莠子的鲜重防效大于80%,对冀谷39的株高和鲜重没有影响。结果揭示了抗除草剂谷子品种冀谷39对氰氟草酯有较强的耐药性,普通谷子品种豫谷18对氰氟草酯没有耐药性,合理使用氰氟草酯能够有效防除冀谷39田间的多种禾本科杂草。     

谷子苗期除草剂的安全性及杂草防效研究

针对谷子对大多除草剂较为敏感,人工除草费时又费工,制约谷子生产发展这一问题,以晋谷50号为材料,筛选10%谷友可湿性粉剂、40%扑草净可湿性粉剂、56%2甲4氯纳可湿性粉剂及57%的2,4-D丁酯乳油4种目前在生产上较常用的除草剂,在谷苗三叶一心期茎叶喷施,对谷苗的安全性及杂草的防治效果进行研究。结果表明,10%谷友可湿性粉剂在谷子苗期喷施,剂量浓度为1.8kg/hm2时防草效果最佳,施药40d后杂草平均株防效达65.23%,杂草平均鲜重防效达89.90%,对谷子安全并起到有效控制谷田杂草的作用,谷友可作为谷子苗期谷田的理想除草剂。其余3种除草剂,谷子苗期使用对谷子安全性及杂草防效均不如谷友,可作为谷友的辅助除草剂,在阔叶草害严重时适当剂量配合使用。     

Effect of some Herbicides on Oil Seed Rape (Brassica Napus L.) and Associated Weeds

Two field experiments were conducted during 1984/1985 and 1985/1986 seasons to study the effect of Alachlor, Metolachlor, Pendimethalin, Diphenamid, CGA 10832 and Oxadiazon as pre-emergence herbicides and EPTC as presowing herbicide at two doses as well as hand-hoeing treatment on weed spread and rapeseed yield under Egyptian conditions. All the tested herbicides except "Oxadiazon" gave satisfactorily good annual grass weed control up to harvest time. While, Oxadiazon and Diphenamid at both doses controlled adequately the growth of annual broad-leaved weeds. The highest rapeseed yield was achieved under the application of Metolachlor at 2.4 and 3.6, Pendimethalin at 1.8, Diphenamid at 1.8, CGA 10832 at 2.4 and Oxadiazon at 1.2 kg a.i./ha. While, Pendimethalin at 2.4, Diphenamid at 2.4, CGA 10832 at 3.6, Oxadiazon at 1.8 and EPTC at 5.5 kg a.i./ha exhibited an obvious phytotoxic effect on rapeseed plants.     

Agronomical Performance Among Farro Species and Durum Wheat in a Drought-Flat Land Environment of Southern Italy

The aim of this study was to evaluate the agronomical performance of old unhuUed wheat species (farro) in comparison with an old cultivar of durum wheat, selected for morphological and rusticity characteristics similar to farro, in a drought-flat land environment of southern Italy. The trials were carried out during the 1992/93 and 1993/94 growing seasons. Agronomical responses concerned the behaviour of the different species to weeding treatment (diclofop-methyl, 568 g a.i, ha⁻¹) and to three (0%, 50%, 100%) artificial weed levels with Avenafatua and Phalaris arundinacea with respect to grain yield and its components, plant morphological aspects and two qualitative characters. In all of the species the weeding treatment increased the mean values of almost all the parameters analysed except for days to head and grain protein content which remained constant. The effect of weed treatment on the characters considered was a general decrease of mean values when weed level was increased. The grain protein content showed an opposite trend. As far as the grain yield alone is concerned, yielding differential in medium and large farro decreased by 3% whereas in small farro it increased by 4.3% vs, durum wheat when no weeding and weeding treatments were compared. Small and large farro resulted more susceptible than medium farro and durum wheat to weed treatment. In fact, these latter showed, at the maximum weed level, the same grain yield loss as small and large farro at the 50% weed level. Small farro was the most susceptible species, while Triticum dicoccum showed similar affinity and behaviour to durum wheat.     

Modellversuch zur Beschreibung von Konkurrenzvorgängen zwischen Sommerweizen und einer aus Capsella bursa-pastoris L., Stellaria media L. und Alopecurus myosuroides Huds. bestehenden Mischverunkrautung

Investigation to Describe the Competition between Spring Wheat and a Weed Population Consisting of Capsella bursa-pastoris L., Stellaria media L. and Alopecurus myosuroides Huds.
When controlling weeds in cereals using economic threshold as criteria, weed populations must be evaluated for their potential to cause damage at a very early stage. As well as information of actual weed density or weed ground cover, further knowledge about the species specific growth and competition between weed populations is important.
For this purpose the growth and competition between the weeds Capsella bursa-pastoris L., Stellaria media L., Alopecurus myosuroides Huds. and spring wheat ( Triticum aestivum L.) as a model of a typical weed mixture in cereals were studied in a container experiment. The growth with time of individual species was documented using true colour image processing. In that these measurements are non-invasive, the system lends itself specially to time-dependent analyses. The increasing amount of ground covered by leaves between two observation times served as a parameter to evaluate the increase in biomass over this time period and could be used as a evaluation of the competitiveness of the weed species studied.
The results can be summarized as follows: 1) Stellaria media L. proved to be the most competitive of the studied species. 2) The competition to spring wheat from each weed species was similar. 3) A multi species weed population had a tendenci to a lower competitiveness to spring wheat, than a weed population of only-one species.
The importance of this and other similar studies for the improvement for the prediction of economic weed thresholds to estimate weed populations in early stages will be indicated.     

油-棉连作棉田油菜秸秆覆盖对棉田杂草发生及土壤杂草种子库的动态影响

在安徽省沿江棉区开展了油菜秸秆覆盖对棉田杂草发生、棉花生长及土壤杂草种子库影响的研究。结果表明：随着油菜秸秆覆盖量的增加,对棉田杂草的抑制效果增强。与未覆盖秸秆且不除草处理相比较,7000 kg/hm²秸秆覆盖量处理棉花单株铃数和子棉产量显著提高。7000 kg/hm²秸秆覆盖量处理在覆盖后30、60、120天逐步减少0~20 cm土层杂草种子库密度,与全程除草剂处理较一致;随着覆盖量减少,对0~20 cm土层杂草种子库密度的降低幅度减小。全程除草剂处理降低0~5 cm土层杂草种子库多样性,而油菜秸秆覆盖则可能增加0~5 cm土层的杂草种子库多样性。3500 kg/hm²覆盖量+秸秆覆盖30天后喷施除草剂处理的抑草效果和增产效果与全程除草剂处理较一致。因此,在安徽省沿江棉区油-棉连作棉田推荐使用3500 kg/hm²油菜秸秆覆盖量+秸秆覆盖30天后喷施除草剂。     

2,4-滴微乳剂对外来入侵杂草薇甘菊的生物活性与防治效果研究

为了寻找防除薇甘菊的高效药剂,本研究测定了2,4-滴微乳对外来入侵杂草薇甘菊的生物活性和田间防治效果。通过测定抑制率求取抑制薇甘菊生长90%的有效剂量ED90,以覆盖度防效和鲜重防效为指标研究其田间防治效果。盆栽试验结果表明：喷施后30天,18% 2,4-滴微乳剂(ME)抑制薇甘菊茎叶生长的ED90值是制剂用量125.9 mL/667 m2,抑制地上部和根部鲜重的ED90分别为制剂用量99.3 mL/667 m2和141.3 mL/667m2。在田间条件下,喷药处理后15、30天,供试18% 2,4-滴ME制剂用量60~180 mL/667 m2处理时覆盖度防效均为90%以上,显著优于或相当于70%嘧磺隆WP制剂用量25 g/667 m2处理防效。处理后45天时,18%2,4-滴ME制剂用量120、180 mL/667 m2对薇甘菊的鲜重防效均在90%以上,与70%嘧磺隆WP制剂用量25 g/667 m2处理防效差异不显著。供试18% 2,4-滴ME对薇甘菊选择作用明显,具有“灭薇保草”的效果,适用于林地、非耕地和城市绿化地防治薇甘菊,有利于受薇甘菊破坏的生态环境的保护与恢复。     

Inheritance of Isoproturon Tolerance in Durum Wheat Transferred from Triticum monococcum

The inheritance of isoproturon tolerance exhibited by the selected progenies of durum wheat was investigated. This tolerance to the herbicide isoproturon had been transferred from Triticum monococcum to durum wheat cultivars. It was shown to be conditioned by a single dominant gene     

Effect of spring fertilization on ecosystem services of organic wheat and clover relay intercrops

Nitrogen (N) deficiency and weed infestation are main factors limiting yield and yield stability in organic wheat. Organic fertilizers may be used to improve crop performance but off-farm input costs tend to limit profitability. Instead, forage legumes may be inserted into the crop rotation to improve the N balance and to control weed infestation. In opposition to simultaneous cropping, relay intercropping of legumes in organic winter wheat limits resource competition for the legume cover crop, without decreasing the performance of the associated wheat.The aim of this study is to evaluate the effect of spring organic fertilization on the performance of intercropped legumes and wheat, and on services provided by the legume cover.Two species of forage legumes (Trifolium pratense L. and Trifolium repens L.) were undersown in winter wheat (Triticum aestivum L. cv Lona) in five organic fields during two consecutive crop seasons. Organic fertilizer was composed of feather meal and applied on wheat at legume sowing. The cover crop was maintained after the wheat harvest and destroyed just before sowing maize.Spring organic nitrogen fertilization increased wheat biomass (+35%), nitrogen (+49%), grain yield (+40%) and protein content (+7%) whatever the intercropping treatment. At wheat harvest, red clover biomass was significantly higher than white clover one (1.4 vs. 0.7 t ha⁻¹). Nitrogen fertilization decreased forage legume above-ground biomass at wheat harvest, at approximately 0.5 t ha⁻¹ whatever the specie. No significant difference in forage legume biomass production was observed at cover killing. Nitrogen accumulation in legume above-ground tissues was significantly higher for white clover than for red clover. Both red and white clover species significantly decreased weed infestation at this date. Nitrogen fertilization significantly increased weed biomass whatever the intercropping treatment and decreased nitrogen accumulation in both clover species (−12%).We demonstrated that nitrogen fertilization increased yield of wheat intercropped with forage legume while the performance of legumes was decreased. Legume growth was modified by spring fertilization whatever the species.     

不同除草剂处理水平对小麦品种‘豫麦49’生长的影响

为了探讨飞防前提下有效药剂的安全使用范围,采用田间小区试验,以常量喷雾方法模拟田间飞防操作情况下不同除草剂处理水平对小麦品种‘豫麦49’的生长影响试验。结果表明,供试除草剂在推荐用量、2倍剂量和4倍剂量下小麦旗叶叶绿素含量、N含量、光合速率、株高、叶锈病病情指数均显著降低。施用3.6%二磺·甲碘隆WDG2倍剂量和15%炔草酯WP4倍剂量下旗叶叶绿素含量和N含量不降反升。推荐剂量、倍量下小区试验产量显示增产效果;而当施用剂量达4倍剂量时,产量均明显下降。