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21.
乙草胺对马铃薯田杂草防除试验研究   总被引:1,自引:0,他引:1  
以大田马铃薯为研究对象,采用随机区组设计,研究播后立即喷施乙草胺(A处理)和播后14天喷施(B处理)对马铃薯田中多种杂草的防效。试验结果表明,乙草胺在2.25~3.75L.hm-2剂量范围内,A处理和B处理均可有效地防除单子叶和双子叶杂草。待马铃薯出苗后15天调查结果如下:A处理株防效在93.08%~95.28%之间,总鲜重防效在94.6%~99.37%之间;B处理株防效在93.0%~97.16%之间,总鲜重防效在97.38%~98.22%之间,而不同处理下不同剂量乙草胺杂草防效差异不明显,且对马铃薯生长无不良影响。从不同施药时间对后茬作物影响角度出发,建议播后立即喷施3.00L.hm-2防除效果较好。  相似文献   
22.
通过对安庆市水稻种植方式的系统调查发现,直播面积约占水稻种植面积的40%,机插秧面积占35%~40%,抛秧和人工手栽面积占20%~25%,其中种植大户主要是直播和机插秧,一般农户手栽和抛秧所占比例较大。本文分析了其种植成本、效益、生产上存在的问题,并提出了发展对策,以期为水稻直播生产提供参考。  相似文献   
23.
朱海霞  马永强 《草地学报》2019,27(5):1301-1308
为研究内生菌HL-1可湿性粉剂的制备材料及其除草活性,本试验采用单因素法筛选生防除草内生菌HL-1最适碳氮源、固体发酵基质、适宜载体和助剂,制备可湿性粉剂,并进行盆栽和田间小区接种,测定其除草活性。结果表明:HL-1最适碳氮源分别是蔗糖和酵母浸粉,最适固体发酵基质为麦麸,最适载体与助剂为硅藻土、膨润土、羧甲基纤维素和可溶性淀粉;在苗期盆栽和田间小区试验中,菌株HL-1可湿性粉剂对繁缕(Stellaria media L.)、灰藜(Chenopodium album L.)、藜(Chenopodium glaucum L.)和密花香薷(Elsholtzia densa Benth.)4种杂草均表现出较强致病性,盆栽试验中对繁缕的发病率和鲜重效分别是85.50%和84.74%,小区试验中对繁缕的发病率和鲜重效分别是84.50%和85.36%。本试验制备的内生菌HL-1可湿性粉剂,可作为生防菌剂有效控制繁缕、灰藜等杂草。  相似文献   
24.
文内从生态学角度。论述了杂草的防治。即诱导植物种群优势向目的树种种群发展;利用造林树种的需要性;栽植培育繁殖能力强的树种。  相似文献   
25.
The design of integrated weed management (IWM) systems is essential in order to reduce the use of herbicides for crop production. By combining different weed management practices, herbicides may be used at lower doses than normally recommended, while still maintaining acceptable weed population levels. The purpose of this study was to develop tillage strategies, with and without herbicides at reduced rates, appropriate for different weed populations. The influences of type and time of stubble cultivation, harrowing and mouldboard ploughing on the weed flora were followed during 1988–1994 in eight long-term field trials situated in southern Sweden. Spring-sown barley (Hordeum distichon L.) and oats (Avena sativa L.) dominated the crop rotations. Herbicides were either omitted or used at ca. 50% of a full dose. The perennial species Sonchus arvensis L. was favoured by omittance of ploughing but was better controlled by late ploughing not preceded by stubble cultivation; the reduction in the latter treatment being 74%. Stubble cultivation succeeded by ploughing reduced biomass of Elymus repens (L.) Gould. by 90% compared with ploughing solely. Early ploughing reduced the biomass of the species by 50% compared with late ploughing. The species Cirsium arvense (L.) Scop. was highly favoured by early ploughing followed by late autumn harrowing, the biomass of the species being six-fold higher than in other treatments. Compared with other treatments, stubble cultivation favoured four annuals but efficiently controlled three others, while omittance of ploughing favoured six annual and two perennial weed species. Late ploughing not preceded by stubble cultivation favoured four annual and one perennial species, while early ploughing was more efficient than late ploughing in controlling two of the annual species. Influences of treatments on weed species were frequently moderated by interspecific competition resulting in inconsistent response at different sites. Herbicides reduced the number of species by three, from 11 to eight species, averaged across sites and tillage systems. Influences of treatments on diversity were not consistent, since weed floras differed between sites and since some of the species responded inconsistently to tillage and herbicides. This study shows that by utilizing appropriate tillage strategies it is possible at many sites to maintain acceptable weed population levels, although herbicides are used at 50% lower doses than is normally recommended. The timing and type of tillage have to be chosen for being as efficient as possible to the most troublesome weed species at a site.  相似文献   
26.
经1995 ~1998 年对日本结缕草草坪中杂草发生规律及其防治体系进行了初步研究,研究结果表明,一年四季草坪中均有杂草发生,但主要以2 ~6 月和9 ~12 月为主,并根据杂草的发生情况,建立了以化学除草为主的防除体系,提出了适宜的除草剂种类、剂量以及用药时间和方式。  相似文献   
27.
A. Andersen   《Crop Protection》1999,18(10):407-657
In five field experiments run for four years the infestation of pests and the activity of carabids and staphylinids were compared in autumn ploughed and reduced tillage (no-tillage or spring harrowing) plots. Differences were generally most evident in experiments with no-tillage. Weed cover was denser in reduced tillage, and could explain much of the differences. The agromyzid Chromatomyia fuscula was most common in autumn ploughed plots, probably due to healthier plants. Thrips numbers were correlated with grain quality in no-tillage plots. Field slugs were most common in reduced tillage, and were positively correlated with weed cover. Generally, more carabids and staphylinids were caught in reduced tillage. This was especially true for Amara-species and Loricera pilicornis, Philonthus cognatus and Tachinus signatus, which also were positively correlated with weed cover. Aloconota gregaria, Bembidion quadrimaculatum, B. lampros, Harpalus rufipes and Trechus quadristriatus were more common in autumn ploughed plots, several of them preferring open soil.  相似文献   
28.
调查结果表明,陕西省关中西部麦田杂草主要有22种,分属10科22属,危害严重的有10种。6个生态区杂草种类,优势组合分布特点有一定差异,尤以地灌区与塬区旱地存在较大差异。影响杂草分布的因素 地理条件外,还有人为传播,耕作栽培,降雨量,化学除措等。  相似文献   
29.
两种新型除草剂对麦田恶性杂草防除效果   总被引:3,自引:0,他引:3       下载免费PDF全文
推广使用高效、安全的麦田除草剂是控制节节麦等麦田恶性杂草严重发生的经济有效的措施之一,本试验采用田间试验方法研究了AEF1300603OF(3%世玛油剂)及WG13A13.6WG对麦田恶性杂革的防治效果。试验结果表明,WG13A13.6WG对麦田杂草防除效果显著,其最佳用量为25~35g/667m^2。在小麦返青期,对节节麦防效达85%~95%,对蜡烛草的防效达85%~90%,对播娘蒿、荠菜的防效达100%,对猪殃殃、婆婆纳等抗性较强的杂革防效也在90%~100%,均高于AEF1300603OF的防除效果。收获首田间调查发现防效趋势与首期调查结果一致。而且WG13A13.6WG防除杂草后使小麦的增产幅度在16.27%~25.48%。  相似文献   
30.
[目的]掌握红塔区园林绿地春、夏两季杂草的种类、种群结构及发生情况。[方法]分春、夏两季研究云南省玉溪市红塔区园林绿地杂草发生危害规律。[结果]玉溪市红塔区园林绿地春季杂草有29种,分属17科,其中菊科9种,占31.03%;禾本科3种,占10.34%;伞形科、大戟科2科各2种,分别占6.90%;酢浆草科、苋科、唇形科、蔷薇科、鸭跖草科、车前科等13科各1种,均占3.45%。夏季杂草有38种,分属20科,其中菊科12种,占31.58%;禾本科3种,占7.89%;伞形科、蝶形花科、大戟科、酢浆草科、蓼科5科各2种,均占5.26%;藜科、仙茅科、莎草科、鸭跖草科、车前科、十字花科等13科各1种,均占2.63%。[结论]初步了解了红塔地区春、夏季杂草种类、分布、种群结构、危害程度及不同类型绿地的危害差异,为综合防除春、夏两季杂草提供了理论依据。  相似文献   
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