麦田杂草与化学防除

我省稻后种麦前期土壤湿润,适于杂草滋生,发生密度大,长势猛,大量摄取水肥,恶化田间环境,加重病虫发生,严重影响麦苗生长和夺取高产。人工除草花工多且不及时,密植更增加了中耕除草的困难。针对我省特点,我们于1974—1979年在昆明和玉溪进行了麦田化学除草应用技术的研究和示范工作,现将试验、示范结果摘要如下。 一、麦田杂草的发生特点 据我所和大理、陆良、文山、保山、腾冲、永胜等农科所调查资料,看出麦田杂草的发生有以下特点: (一)发生特点:我省普遍发生的杂草是一年生(越年)杂草,主要有看麦娘、棒头草、繁缕、黄花苜蓿等几种,其次还有荫草、早熟禾、荩草、鼠曲、蓼、藜、荠、野豌豆等。     

玉米田化学除草对产量的影响

1990～1991年我们进行了玉米田化学除草试验,目的是探索能否用化学除草取代人工中耕松土除草。一、试验设计 1.中耕松土除草。玉米3～5叶期,杂草基本出齐时,人工中耕松土除草1次,以后每隔15天左右人工拔草1次,保持田间基本无草。 2.人工拔草。杂草出苗后每隔15天拔草一次,基本上保持田间无杂草,但始终不中耕。 3.化学除草。玉米播后苗前进行化学除草,以后视情况辅以人工拔草,但自始至终不中耕。化学除草又分为以下两种:(1) 灭茬播种玉米田化除。亩50％乙草胺乳油100毫升,于玉米播后苗前兑水40～50千克喷雾。(2) 板茬播种玉米田化除。套种玉米或麦收后板茬播种的玉米,     

麦田使用绿麦隆如何避免药害

绿麦隆用于麦田对单子叶及部分双子叶杂草有一定的防除效果,并具提高作物产量等优点。据试验其除草效果一般在70—90％左右,作物增产幅度在7—70％左右。但使用不当易产生药害,严重时还能影响到下季作物的生长。经反复试验证明每亩用药量0.25公斤,在土壤干燥的情况下及壤土田使用,浓度在400倍左右,土壤湿度大时及土壤沙性重的田块300倍,一般每亩喷药液     

氟乐灵等防除夏大豆田杂草

东台市沿海旱粮地区,夏大豆以春玉米间套种为主,只部份麦(油)后单种。田间以马唐、狗尾草、蟋蟀草、旱稗、千金子等禾本科杂草为主。苗期需人工除草2次,每亩需5个工。此的正值梅雨季节高温多雨,杂草暴发为害,人工除草效果差,一般产量损失2至3成。1985—1987年对夏大豆的化学除草进行了试验与示范,3年已示范2.13万亩,每亩可省工4.5个,增产大豆30—50公斤。有关技术如下:     

重庆市水稻前期草虫害综合防治策略的研究

重庆市常年种植水稻６３０万亩左右，其中冬水田４００万亩。据统计，我市每年稻田草害发生面积约２００～３００万亩左右，草害严重的约占１００～１５０万亩。杂草主要在水稻生育前期严重危害，与水稻争光、争水、争肥．严重地影响水稻的正常生长，据全国有关专家试验测定，一般杂草危害导致水稻减产７～１５％，严重的达２０～５０％。因此，搞好水稻前期的化学除草工作保障水稻增产丰收有着十分重要的作用。除此之外，水稻前期一代二化螟防治的好坏同样与水稻丰收有着紧密的联系，水稻前期主要害虫有一代二化螟、蓟马、蚜虫，而一代二化…     

广西主要作物轻型农艺的发展与化除技术

在我国随着传统农业向现代化农业转变，以化学除草技术为依托，“免少耕”为特征的轻型农艺获得肯定和发展。上世纪中期，在麦田、棉田等建立免耕技术曾有报道。作者从上世纪60年代起对广西主要作物的轻型农艺技术曾作深入研究并取得一系列成果。本文重点对稻作早播稀植秧田少耕、直播田化学除草少耕、抛秧田免耕、移栽稻田化除少耕、双季稻夏种免耕、甘蔗地化除少耕、南方果园除草少耕、西瓜、草莓免耕等进行总结报道。     

万亩花生使用地乐胺除草效果好

1987年,我县1万余亩花生地使用地乐胺防除杂草,收到了显著效益。通过多点试验和大面积示范,总结如下: 1.防草效果好 旱地花生亩用48％地乐胺乳油(下同)150—200毫升除草效果93.5—97.3％;水田花生200毫升平均防效92.3％;地膜覆盖花生防效达96％。对马唐、狗尾草和稗草等有特效,对多年生莎草科杂草防效差。 2.省工节支 往年花生中耕锄草两遍,每亩花工8—10个,草害严重的花工更多。用地乐胺除草,每亩只需花施药工0.2个,培土工1个;每工以3元计节支20.4—26.4元。并较好地解决了花生锄草用工与早稻田     

赛克津混用防除黑穗醋栗园杂草

我处是人少地多的黑龙江垦区,又是国家重要的大豆商品粮基地,杂草危害是大豆高产的主要限制因子之一。据调查,有杂草23科,47属,67种,土壤中草籽全层感染,出土杂草每平方米达千株以上,重者达万株以上,从早春到晚秋,各种杂草陆续出土危害,过高温多雨,则暴发齐长,大豆减产达50％,个别地块甚至绝产。化学除草收到了工省效宏的效果,豆田的主要杂草一稗草几乎被彻底征服,但宿根性、多年生和双子叶草却又繁衍起来。 1987年,我们在6队和11队共1260亩的大豆田实施了“以轮作换茬,科学耕作,加强选种,机械苗耙,中耕除草,并进行除草剂混用(6队用氟乐灵加灭草猛进行播前土壤处理,11队用杜尔加2.4D-丁酯进行播后苗前喷撒地表),辅以后期人工拿漏网大草”的综合灭草措施,收到了良好的灭草效果,从而使经济效益大幅度提高。普阳农场6队,综合     

小麦早稀播栽培苗期化除的效果

近年来的许多研究表明,小麦早、稀播栽培是实现高产的有效途径。但由于麦田杂草发生日趋严重,对早稀播小麦高产带来威胁,因而搞好麦田化学除草显得十分重要。为了加深对早稀播麦田化除的认识,进一步完善小麦早稀播高产栽培的配套措施,我们于1990～1991年度和1991～1992年度分别在双楼镇、海安镇进行了早稀播小麦的苗期化除试验。一、材料和方法 (一) 供试田块:前茬为中稻,土质粘壤。近年来采取稻“旋”麦“免”的耕作方式。田间杂草基数高,以看麦娘为主。其中双楼点看麦娘占总草数的98％,海安点占82％,其余为猪殃殃、牛繁缕等双子叶杂草。 (二) 供试除草剂:双楼点为绿麦隆(海安县农药厂产,亩用300克)、绿平合剂(亩用绿麦     

盖草能在大豆田的使用技术

盖草能(Dowco—453)对防除阔叶作物田1年生和多年生禾本科杂草具有选择性效果,剂型有12.5％和24％乳油。我们对该药进行了两年温室、小区和大田示范试验,在大豆和棉花苗期及中、后期使用,防除禾本科杂草的效果可达95％以上,对作物安全、增产显著。     

THE USE OF THREE SIMPLE,RAPID BIOASSAYS ON FORTY-TWO HERBICIDES*

Three rapid bioassays were tested on forty-two herbicides having several different modes of action. A 50% or greater inhibition of growth was found at 1 ppm with thirty-one herbicides in one or more of the bioassays. Of the remaining eleven herbicides, seven were detected at 10 ppm, two at 20 ppm and two at 30 ppm. The techniques used were a Chlorella bioassay, a root bioassay with sorghum, oat and cucumber and a shoot bioassay with sorghum and oat. The duration of the bioassays was 1, 2 and 4 days respectively. As a general rule, the Chlorella bioassay was especially sensitive to photosynthetic and respiratory inhibitors but not sensitive to herbicides with other modes of action, whereas the root and/or shoot bioassays were sensitive to most of the herbicides except the photosynthetic inhibitors. The use of the three bioassays simultaneously is suggested as a possible method for primary screening of herbicides.     

THE DEVELOPMENT OF HERBICIDES FOR POTATOES

Summary. Since 1961 the Weed Research Organization has been testing and developing herbicides for weed control in potatoes. Inthe three experiments which are reported, herbicides were compared with other forms of weed control. The first experimentin 1961 was exploratory and compared yields following hand-weeding versus no weed control versus several promising herbicides. The highest yield was produced by the hand-weeded crop. Several herbicide treatments applied before crop emergence gave useful selective weed control.
Assuming weed control to be necessary, selected herbicides were then compared in 1962 and 1963 with conventional mechanical cultivations. In both years successful weed control by herbicide resulted in a higher yield of potatoes than did mechanical cultivation although the soil-acting chemical used in 1962 caused some crop damage. The 1963 experiment included triangular planting patterns, at normal and high plant densities. Increases both in gross and marketable yield were obtained at normal plant density with the triangular arrangement as compared with the row crop. The high plant population resulted in the largest gross yield but a lower yield per plant and smaller average tuber size.     

油菜田遏蓝菜发生规律与化学防除

试验明确,青海湟中地区遏蓝菜全生育期约为115d,出苗高峰期为5月上旬至中旬。种子发芽出苗最适土壤深度为1.0～3.0cm。花期约34d,果期约20d,单株结籽量平均690粒。种子有休眠习性,室外埋入土层8d萌发率为1.5％。遏蓝菜与油菜竞争危害表现在油菜全生育期,植株含氮、磷、钾量比油菜高2.3％～225.0％。遏蓝菜发生量与油菜籽产量呈极显著负相关关系,回归方程为y=203.15-0.53x。采用3种除草剂及其混剂对遏蓝菜的防除效果均在90％以上,油菜籽增产显著。     

应用赤眼蜂防治玉米螟的放蜂量试验

1987～1988年在辽宁省西丰县、岫岩县等老放蜂区和新民县新放蜂区,进行赤眼蜂防治第一代玉米螟的示范试验。结果证明,由放蜂量1～1.5万头,可以代替过去推广的亩放蜂量2～3万头。用低蜂量示范试验进一步证明,亩放蜂量1万头,在玉米螟中等偏重的发生年份,也能取得比较理想的防治效果,值得推广应用。     

红铃虫为害青铃对棉花产量和单价的影响

红铃虫Pectinophora!gossypiella(Saunders)的为害可分为直接取食为害和间接诱发病害。两年来每隔5天左右系统剥查吐絮棉铃,分析结果表明,受害棉籽产量损失平均为60.92克籽棉/千粒,每头幼虫平均为害2.03粒棉籽。根据单铃幼虫数估计的每条幼虫为害造成的产量损失是籽棉0.24克,皮棉0.101克,其中直接为害分别是0.133克和0.0467克,间接为害分别是0.11克和0.0543克。棉籽受害后皮棉等级降低4级,单价降低31.6%。百斤皮棉单价损失是9.383元/条/铃,其中直接为害5.559元/条,间接为害3.824元/条。应用皮棉产量损失0.101克/条和百斤皮棉单价损失9.383元/条/铃,推导了估计产值损失的公式,可以在生长期的不同阶段估计当时红铃虫所造成的产值损失。     

HERBICIDE PRACTICE IN ARABLE FARMING DISTRICTS OF EASTERN ENGLAND, 1959-60

Summary. Information on the use of herbicides in the 1959-60 crop year was collected from a stratified random sample of farms in each of four arable farming districts in Eastern England.
In each of the surveyed districts about 80% or more of the area under cereals, 10-20% of other tillage crops and about 10% of the grassland was treated with herbicides. In the three diatricts where peas were widely grown most of this crop was also treated. Contract services were used most on the smaller farms.
MCPA was the most widely used herbicide on cereals, but in two of the four districts mecoprop was also often used. Manufacturer's reeommendations for rates of application were followed fairly closely for MCPA on cereal crops which were not undersown but MCPA was also used on much of the undersown cereals in spite of the risk of damage to the legumes. MCPB and mecoprop were often applied to cereals at rather lower rates than those generally recommended, Little detailed information was obtained about when herbicides were applied but clearly most farmers were influenced more by general crop appearance (and possibly date) than by the stage of growth of crop or weeds.
The weeds most often mentioned by farmers as occurring on areas treated with herbicide were Cirsium spp., Sinapis arvensis. Galium aparine, Stellaria media, Chenopodium album and Rumex spp. The weeds which were most frequently difficult to control were Avena spp. Polygonum persicaria, Tussilago farfara, Stellaria media and Matricaria maritima ssp. inodora. The herbicides used were usually appropriate for the weeds which they were intended to control and nine out of every ten farmers asked were satistified with the results of treatment; it was very rare for any detrimental effect on crops to have been noted.
L'emploi d'herbicides dans quatre régions agricoles de l'est de l'Angleterre 1959-60     

锐劲特对稻田主要捕食性天敌影响的研究

采用田间试验的方法,进行了锐劲特、三唑磷、杀虫双及锐劲特与甲胺磷混用对稻田主要捕食性天敌影响的研究。结果表明,施用5%锐劲特SC30ml/亩1次,药后28d,对天敌的杀伤率分别为蜘蛛0.92%、瓢虫2.97%、步甲3.33%、隐翅虫6.83%、宽黾蝽7.14%,低于18%杀虫双AS250ml/亩及20%三唑磷EC120ml/亩2次的杀伤率。5%锐劲特SC10ml/亩+50%甲胺磷EC80ml/亩对天敌的杀伤作用较大。     

苏云金杆菌与杀灭菊酯防治红铃虫的试验

苏云金杆菌(Bailus thuringiensis)140或018工业菌剂每亩用200～255克,加杀灭菊酯20%乳剂每亩8毫升混用防治第二、三代红铃虫,虫口减退率和铃害下降率分别为80.5～93.4%和68.8～84.6%;杀灭菊酯每亩40毫升单用效果分别为96～97.2%和84.6～95.8%,都能有效控制红铃虫的危害。棉花产量测定表明,菌剂加菊酯混用使皮棉增加21.3～30.9%,菊酯单用增加11.4%。     

4种茎叶处理除草剂对半夏田杂草的防除效果

为有效解决半夏田草害问题, 选择4种茎叶除草剂进行半夏田杂草防除田间药效试验。结果表明:10%乙羧氟草醚EC 50~60 mL/667m2 (制剂用量,下同)处理与240 g/L乳氟禾草灵EC 20~30 mL/667m2处理能有效防除半夏田金腰箭、辣子草、土荆芥、金荞麦、紫花香薷、针筒菜、尼泊尔蓼等阔叶杂草, 且对半夏安全, 药后21 d对阔叶杂草株防效、鲜重防效均达90%以上, 与禾本科除草剂8.8%精喹禾灵EC 40 mL/667m2或108 g/L高效氟吡甲禾灵EC 30 mL/667m2搭配使用对半夏田大部分杂草能实现较好防除。但两种阔叶除草剂持效期较短(30 d左右), 生产上可根据施药后期田间杂草发生情况, 采用人工拔除或进行第2次化学防除; 施药应避开中午高温时刻, 以免造成此类阔叶除草剂药害。研究结果可为半夏田除草剂的合理选择和应用提供科学依据。