The effect of benomyl and thiophanate-methyl on earthworm populations in apple orchards

The use of the fungicides benomyl and thiophanate-methyl on experimental orchard plots for 3 years and of benomyl on a commercial orchard for 1 year resulted in a drastic reduction of earthworm populations. The species of earthworms affected were Lumbricus terrestris, L. castaneus, L. festivus, L. rubellus, Allolobophora caliginosa, A. chlorotica, A., longa, A. rosea, A. tuberculata and Octolasium cyaneum. L. terrestris and A. chlorotica were more affected than the other species, both being virtually eliminated after 2 years' spraying. The depleted populations of species other than L. terrestris and A. chlorotica recovered to normal levels after a 2-year rest period following a single year's treatment with benomyl (1.40 kg/ha). The role of the surface-feeding L. terrestris is discussed in relation to the spray fall-out on the sward and to grass management.     

Effect of soil-injected benomyl on resident earthworm populations

Soils pressure-injected with benomyl (36 g/m²) ¼ 1, 2 or 3 years previously or at 18 g/m² 4 years previously were examined to determine the earthworm populations. Earthworms that emerged within 20 min following a soil drench with formalin were counted. A significant reduction in the earthworm population occurred soon after benomyl treatment; however, within months the earthworm population increased substantially. The earthworm populations in plots treated with benomyl one or more years previously did not differ significantly from untreated plots.     

水盆式性诱剂诱捕器对苹果园昆虫种群的影响

通过对有机苹果园和常规苹果园的系统调查,调查分析了果园释放性诱剂对园内目标害虫、天敌及中性昆虫的诱集作用。结果表明:无论在有机苹果园还是常规苹果园,性诱剂均对天敌昆虫和中性昆虫具有一定的诱杀作用,且益害比在有机园中为2:1和2:3之间,在常规园中则在3:1和1:10范围内。水盆式性诱剂诱捕器的使用对自然天敌在果园中的控害作用有明显的影响。     

Side effect of some fungicides on the mite population in an apple orchard in Croatia

The research into the side effect of fungicides used in the control of the most serious disease in apples (Venturia inaequalis) i. e. the research into the influence of fungicides on the population of phytophagous mites, was carried out at Nedeliŝće (North-West Croatia) during 1997 and 1998. The study is related to the population of the mites most present in apple orchards, such as red spider mite (Pananychus ulmi) and other mites (Aculus schlechtendali andTetranychus urticae). Fungicides which are known to be effective against scab, i. e.Venturia inaequalis, and used in fruit production in Croatia, were tested in order to investigate their secondary properties which have not yet been studied. The following fungicides were used: cyprodinil, dodine, dichlofluanid + bitertanol (as tank mix), and kresoxim-methyl. The tests were repeated three times; the application time was determined by monitoring the conditions for infection. The treatments were done curatively, i. e. up to 96 h after the onset of infection conditions. The mite population was estimated by the pressing method, which yielded the average number of mites per leaf. All the results were statistically processed by variance analysis and by Duncan’s Multiple Range Test, and are presented graphically and in tables. The paper also presents graphically the climatic conditions, scab infections and application time. The research over two years have shown a pronounced suppressive effect of dichlofluanid + bitertanol on populations of phytophagous mites, while the other fungicides used in the research had a neutral effect on the mite papulation.     

草甘·麦草防除苹果园杂草的效果

草甘.麦草是由麦草畏和草甘膦异丙胺盐复配成的广谱除草剂。田间小区试验结果表明,40%草甘.麦草AS 150~250 m l/667m2对苹果园马齿苋的株防效为100%,对杂草的总株数防效为56.5%~92.0%,总鲜重防效为86.1%~97.3%。     

地膜-秸秆双重覆盖模式下果园土壤养分含量研究

为了研究地膜-秸秆双重覆盖模式对渭北旱塬果园土壤养分含量的影响,对5个不同处理(地膜压玉米秆双重覆盖、地膜压短麦秆双重覆盖、长麦秆压地膜双重覆盖、地膜压长麦秆双重覆盖和无覆盖清耕对照)下果园0~100 cm土层深度范围内的土壤养分含量进行测定,并统计了苹果产量。结果表明:地膜-秸秆双重覆盖模式能显著提高果园土壤养分平均含量,并提升养分有效性;其中地膜压短麦秆双重覆盖处理综合效果最佳,土壤有机质、全氮、碱解氮、速效磷、速效钾含量均显著高于无覆盖对照(P0.05),提高比例分别为29.72%、8.82%、19.35%、51.87%、22.66%;碱解氮含量提高比例高于全氮,说明该模式能够提高氮肥有效性。与无覆盖对照相比,地膜-秸秆双重覆盖模式对土壤剖面养分垂直变异影响不明显,均呈现出随深度增加先降低后缓慢递增的趋势。从提高土壤养分含量和提升其养分有效性的角度出发,利用地膜压短麦秆双重覆盖模式进行果园土壤管理可以成为实现渭北旱塬果园高产、优产、稳产的有效途径之一。     

New trends in orchard spraying1

Since the early part of the century, a steady move in England towards lower volume spraying of orchards has coincided with the progressive introduction of improved spraying techniques. In recent years many growers have adopted very low volume (VLV) spraying (50 litre ha^-1) using spinning-disc nozzles with greatly reduced dose rates, often only 25% of the product label recommendation. On well managed farms, this method of spraying has been successful for several years and considerable savings have been made in pesticide use and labour for spraying. On other farms there have been pest and disease control problems but few growers have reverted to spraying at conventional volume or pesticide rates. Trials evidence from the UK and the Netherlands shows the VLV reduced dose-rate spraying technique to be generally less effective than conventional spraying but usually sufficiently effective for commercial purposes. In the Netherlands a compromise method of low volume spraying (150–200 litre ha^-1) is being adopted on the recommendation of research and advisory services. This method of spraying is gaining popularity in England. Unfortunately, the method of application stipulated on product labels is usually restricted to a minimum water volume and a pesticide dose per ha. It might be desirable for experimental work for registration purposes to be done to explore optimum application methods for individual pesticides. This information on labels, in a simple form, might lead to the more efficient use of pesticides as well as reflecting the range of application methods in use in the industry.     

Metabolism of benomyl in carrot,strawberry and apple

The metabolism of benomyl was studied in carrots treated with high rates of benomyl, and in strawberries and apples treated at normal rates. The same metabolites were observed in both cases though, at normal rates, their concentrations were low but significant. Detected by means of gas-liquid chromatography they were: carbendazim, 2-aminobenzimidazole (2-AB), benzimidazole, 2-aminobenzonitrile, o-phenylene-diamine and the conjugates of carbendazim and 2-AB. o-Phenylenediamine has not hitherto been reported as a metabolite of benomyl. Two unidentified compounds were also observed by gas-liquid chromatography; their mass spectra were obtained by means of combined gas-liquid chromatography and mass spectrometry.     

陕西省苹果园杂草发生情况调查初报

苹果生产是陕西省六大产业之一,栽种面积在40万hm2左右,产量和面积均居全国第二。最近几年,随着农村经济的发展和多元化种植及立体种植业的发展,果园杂草对苹果生产的影响越来越大。为了准确掌握我省果园杂草的种类,为今后选择科学的防除对策提供可靠依据,作者根据陕西省苹果种     

Differentiation in populations of the apple scab fungus Venturia inaequalis on cultivars in a mixed orchard remain over time

The ascomycete Venturia inaequalis causes annual epidemics of apple scab worldwide. Scab development is reduced in mixed cultivar orchards compared with monocultures. In order to use mixtures in commercial production, how the population of scab changes in a mixed orchard needs to be understood, together with how likely a super race, with virulence factors overcoming multiple resistance factors in the mixed orchard, is to emerge and become dominant. This study used simple sequence repeat (SSR) markers to investigate the temporal change of scab populations in two mixed cultivar orchards in the UK to infer the likelihood of emergence of a scab super race. There were no significant differences between the populations at the two sampling times (6 or 7 years apart) in either of the two mixed orchards. In one of the orchards, apple scab populations on different cultivars were significantly different and the differences did not diminish over time. These results suggest that it is not inevitable that a super race of V. inaequalis will become dominant during the lifetime of a commercial apple orchard.     

Evaluation of selective media and bait methods for estimating Phytophthora cactorum in apple orchard soils

Soil plating, with a specially devised selective medium, gave estimates of Phytophthora cactorum in an East Mailing Research Station apple orchard soil up to three times those obtained by dilution and baiting with apple seedlings or cotyledons and using the most probable number analysis.
When the same techniques were applied to a range of soils from apple orchards in south-east England with a history of P. cactorum diseases the plating method failed in most instances, mainly because Pythium spp. rapidly swamped the plates. The dilution/baiting method was applicable to all soils though there was a tendency to underestimate because of anomalous results at lower soil dilutions.
Oospores were the only propagules which could be confirmed as sources of P. cactorum colonies on soil isolation plates.     

The toxicity of benomyl and some related 2-substituted benzimidazoles to the earthworm Lumbricus terrestris

Benzimidazole and its 2-amino analogue were non-toxic to Lumbricus terrestris when administered orally. The fungicidal 2-substituted benzimidazoles (benomyl, carben-dazim, fuberidazole and thiabendazole) and l-(benzimidazol-2-yl)-3-butylurea were highly and equally toxic. The equitoxicity of compounds with widely differing substituent groups suggests a common mode of action—the benzimidazole moiety being the active part of the molecule. It is likely that there is a common mode of action for benzimidazole analogues for both fungicidal activity and earthworm toxicity. There was no detectable effect on the cholinesterase levels of earthworms poisoned by benomyl. But it is confirmed that the cholinesterase inhibitory activity of benomyl in vitro is due to formation of butyl isocyanate.     

渭北果园土壤紧实化改良效果初探

针对长期植果造成的渭北果园土壤内部存在的紧实化问题,本试验通过给果园土壤开“天窗”的方式,拟打破果园土壤内部存在的紧实化层,以期提高果园土壤水分利用效率和土壤内部气体交换。于果树萌芽期,选择土壤质量退化严重的>20 a苹果园3个作为研究对象,在长势相同的果树周围用直径10 cm的土钻打30 cm的深洞,并向深洞内分别填埋：蛭石（Z）、炉渣（L）、石灰+土（S）、蛭石+炉渣（ZL）、蛭石+石灰（ZS）。在果树生长的6—9月,分3次测定土壤含水率及土壤CO₂释放通量。结果发现：(1) 6月初至7月中旬,开设“天窗”的处理周围土壤含水率变化在10.84%~20.42%,而没有开“天窗”的对照只有7.46%~15.96%。9月份,由于连续降雨的原因,各处理果园土壤含水率差异不显著。综合对比各处理发现,添加蛭石+炉渣在调节果园水分方面效果最好。(2)添加不同物料的处理6—9月份“天窗”内表层土壤CO₂释放通量相比对照增加了7.1%~48.3%,而15 cm处相比对照显著降低了6.3%~40.4%;各处理“天窗”周围10 cm处6—9月份表层土壤CO₂释放通量相比对照增加了0.2%~37.1%,15 cm处相比对照降低了6.2%~41.6%,30 cm处相比对照降低了0.6%~26.9%,可见开设“天窗”可以加快郁闭土壤内CO₂气体的释放。另外,添加的物料不同,改良效果也不同,其中添加石灰和蛭石+石灰的处理在改善果园土壤气体交换方面效果较好。     

Teratogenic effects of the fungicide benomyl on posterior segmental regeneration in the earthworm,Eisenia fetida

Earthworms, Eisenia fetida, were treated by surface exposure to the fungicide benomyl at various stages of posterior segmental regeneration. Teratogenic effects of benomyl were observed when worms were treated 7–11 days after amputation (i.e. during the normal period of segmental replication), but not during days 1–5, 13–17, or 19–23. Teratogenic effects included a reduction in the number of regenerated segments, an increased frequency of segmental groove anomalies, and a variety of monstrosities. The effects of benomyl treatment on the number of regenerated segments and frequency of anomalies were dose-dependent within a narrow concentration range (approximately 0.2–5.0 mg litre^?1); at higher concentrations (e.g. 25 mg litre^?1) teratogenic effects were less frequent because the onset of segmental delineation was delayed until well after exposure. Non-invasive electrophysiological recordings from treated worms indicated that functional integrity of giant nerve fibre conduction pathways was established in all anomalously regenerated tail segments, except in a two-tailed monstrosity. The evidence supports the hypothesis that these teratogenic effects derive from an antimitotic mode of action of benomyl on segmental regeneration.     

陇东地区苹果园应用生物活性素的效应

连续2 a在甘肃陇东地区苹果园进行化肥提质增效试验,研究施用生物活性素提高肥料利用效率的可行性,并探讨减施化肥对果园土壤肥力、树体生长发育和苹果产量及品质的影响。2018年在G1、G2两个试验果园设置常规施肥（CK）、常规施肥配施生物活性素（B）两个处理,并在2019年增设G3、G4试验果园,每个果园设置常规施肥（CK）、常规施肥配施生物活性素（B）、减施化肥30%配施生物活性素（RB）和减施化肥30%（R）4个处理。结果表明：2018年施用生物活性素（B）后,G1、G2果园土壤全氮含量有所下降,而叶片含氮量分别提升了11.2%、4.9%,树体的花芽量较对照组分别提高了65%、45%,果实可滴定酸含量降低,果实香气提升;减施化肥30%处理（R）,降低了土壤的pH值,除G1果园外叶片氮素含量均有所上升,其中G2、G3分别提高6.9%、12.9%;在成龄树果园中可提高产量,G1、G3两果园分别提高了35.8%、40.6%,但对施肥量较少的幼龄果园会产生一定的影响;减施化肥30%配施生物活性素（RB）技术应用后,土壤全氮含量和有效磷含量除G4外均略有下降,叶片氮素含量除G2果园外分别提高了15.0%、6.4%、3.0%,且其余树体指标的表现基本优于减施化肥30%处理（R）。在陇东地区果园施用生物活性素可显著促进幼树成花成果,并提高果实香气,减施化肥后总体未对成龄树果实品质产生影响。     

Spray deposit cover and fungicide distribution obtained on intensive apple trees by overhead mobile spraying methods

Spray deposit assessments were made on the leaf surfaces in the top, middle and base zones of intensively grown apple trees sprayed by the conventional largevolume automatic method applying 2250 litres/ha and by fast overhead methods with nozzle booms applying 1125 litres/ha and with mist-blowing equipment applying 562 litres/ha. Qualitative assessment of spray cover, using a 0.05% suspension of Saturn Yellow fluorescent tracer showed that whereas the conventional method gave heavy cover on upper and lower surfaces in all zones, the two overhead methods gave heavier cover on the upper surfaces than on the lower and that an appreciable proportion of the lower surfaces especially in the base zone on trees sprayed by the overhead mist-blower had no fluorescent deposit. Quantitative assessments of copper spray deposits by colorimetric estimations separately on upper and lower surfaces agreed in general with the fluorescent tracer indications, especially the much greater deposits on the upper surfaces on the trees sprayed from overhead. Monitoring of captan spray deposits before and after each successive fungicide application through the season showed that in the three zones the residual and cumulative deposits from the conventional automatic applications were heavier and more uniform than those from the overhead methods which gave lighter deposits on the middle and base zones. In the intervals during which rain fell, most of the captan deposit levels from all methods of spraying were reduced by >70%, whereas during a rainless interval the reduction was 0–45%. The reduction of captan deposit levels during the rainy intervals was significantly greater on the trees sprayed from overhead than on the conventionally sprayed ones. There was a correlation between the percentage loss of captan and the rainfall in the intervals.     

Effect of pest management systems on foliage- and grass-dwelling spider communities in an apple orchard in Hungary

Spider communities (Araneae) inhabiting the canopy, the herbaceous layer and the borders, as well as the populations overwintering on the tree trunks of different aged IPM and conventional apple orchards were investigated in Hungary. Abundance and species richness of entire spider communities in IPM plots were significantly higher than in conventional plots, probably owing to the lower toxicity of pesticides used and higher prey densities. In the case of abundance, similar tendencies were observed in web-building and hunting spider guilds. Age of plantations can significantly influence spider density in the canopy, acting through the prey density. In young plantations, where size of the canopy was smaller and density of the pear lace bug (Stephanitis pyri L.) higher, significantly higher numbers of hunting spider communities were present than in old plantations which had been similarly treated. This relationship was not observed for web-building spiders. Diversity of canopy-inhabiting spider communities was higher in old plots, regardless of the treatments. The effect of the border of the orchard on spider communities was investigated and it was found that when selective insecticides were used, migration of spiders into orchards was increased significantly. When broad-spectrum insecticides were applied, spider densities in the canopy did not differ between outer and inner rows of the orchards. The effect of the treatments and orchard age, both on abundance and species richness of overwintering spider communities on the trunk, showed the same result as for canopy spiders, namely significantly larger spider communities were found in IPM plots and in the young plantation than in conventionally-treated plots and in the old plantation. Broad-spectrum insecticides reduced abundance and species richness of spider communities in the herbaceous layer of the conventionally-treated plot. At the same time, the spider communities of the herbaceous layer of the IPM plot did not differ significantly from adjacent herbaceous plants. A significant overlap exists between spider communities of the canopy and herbaceous layer. Despite chemical treatments, migration from the herbaceous layer into the canopy occurs. The effects of chemical treatments on the dominant species are discussed. There were no significant differences between the differently treated plots in abundance of one of the dominant species Oxyopes heterophthalmus Latreille. However, the other dominant species, Cheiracanthium mildei L. Koch, was more abundant in the IPM plots.     

A comparison of the efficiency of sprays of two drop-size ranges in an apple orchard

A two-season trial of a mist blower-sprayer with improved air-flow characteristics was made to assess the relative efficiency of 120 and 180 μm mass median diameter (MMD) drop-size sprays for the control of apple powdery mildew (Podosphaera leucotricha) and fruit tree red spider mite (Panonychus ulmi Koch) in a hedgerow-type apple orchard. The principal pesticide was binapacryl, applied at two rates for each drop-size. Under typical commercial conditions the smaller drop-size approximately halved the incidence of apple mildew found when the conventional 180 μm MMD drop-size spray was used; there was no conclusive advantage against red spider mite. Unexpectedly large variations occurred in the deposits from the weekly applications and were related to the humidity during spraying.     

果园螟蛾总科部分种类DNA条形码鉴定

为检验DNA条形码在鳞翅目螟蛾总科蛾类鉴定中的可行性,对采自山西省太原市晋源区螟蛾总科26种78头蛾类标本分别提取了DNA,扩增了全部78头标本的线粒体cox1基因和其中75头标本的核糖体28S基因,并通过构建系统发育树、计算遗传距离及种间差异阈值等方法,对所有标本进行了鉴定和比较分析,检验了国际DNA条形码数据库BOLD(the barcode of life data)系统的鉴定成功率。结果表明,基于cox1基因和28S基因的系统发育树鉴定成功率分别为100.00%和97.14%,BOLD系统的鉴定成功率达到了67.94%。基于最大简约法、邻接法和最大似然法构建的系统发育树,鉴定结果均相同。基于cox1基因的种内遗传距离全部小于1.00%,种内种间的遗传距离形成明显的3.00%阈值现象。研究表明,cox1及28S基因均适用于供试螟蛾总科种类的鉴定,核糖体28S基因可以作为DNA条形码鉴定的辅助基因;BOLD系统数据库仍有待充实,且标本鉴定工作相对滞后;不同聚类分析方法对结果影响很小,其中邻接法计算速度快,更适合DNA条形码大数据的分析。     

覆草对果园土壤肥力及苹果产量与品质的影响

在苹果园进行的覆草对土壤肥力和苹果产量与品质的影响试验表明:覆草能有效地稳定土壤温度,保持和提高土壤水分;降低土壤容重,协调土壤大小孔隙比例;增加土壤有机质和养分含量,改善果树营养;提高苹果产量和品质。