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矢尖蚧第一代幼蚧初见日及适宜防治时间与气象条件的关系 总被引:1,自引:0,他引:1
本文对矢尖蚧第一代发生期与气象条件的关系进行了分析,建立了矢尖蚧第一幼蚧初见日的预报方程。根据气象条件与矢尖蚧第一代发生期的关第,提出了不同气象条件下矢尖蚧的适宜防治时间。 相似文献
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柑桔矢尖蚧的为害及其防治 总被引:1,自引:0,他引:1
柑桔矢尖蚧的为害及其防治近几年,矢尖蚧在江西部分桔园泛滥成灾,严重影响树势、产量和品质。笔者对此虫进行了10年的观察和防治研究。1发生规律矢尖蚧在江西赣中地区一年发生3代,雌蚧腹下幼蚧的初见期、高峰期和终见期分别为:第一代5月上旬、5月中下旬和6月下... 相似文献
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密植柑橘园树冠交叉郁闭易使矢尖蚧盛发,大树发生矢尖蚧较幼树重.矢尖蚧第一代发生不整齐,以后世代重叠,加上虫体体表介壳随龄期增加而加厚,抗药性增强,故药剂防治重点应放在第一代1龄~2龄若虫.矢尖蚧危害程度与树势有关,因此应做好柑橘园的综合防治、施肥、防冻及其他病虫害防治工作. 相似文献
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柑桔矢尖蚧在赣州地区各县市均有分布。柑桔矢尖蚧除为害柑桔外,还为害龙眼。为害严重时,叶片干枯、卷缩、脱落,枝条干枯、死亡,导致树势衰弱,引起大量减产;果实被害后,严重影响果实外观,降低商品价值。从1989年开始,笔者对柑桔矢尖蚧的发生规律及其防治技术进行了研究。现将结果报道如下。1发生规律柑桔矢尖蚧一年发生四代,主要以尚未产卵的受精雌成虫越冬,越冬雌成虫于次年3月底或4月上旬产卵,4月上中旬出现第一代若虫,若虫多在柑桔老叶上危害;5月下旬至6月中旬为第M代若虫发生期,这个世代的大部分虫体在新叶上危害,小部… 相似文献
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7月份(小暑、大暑)物候期:幼果膨大、夏梢生长。病虫防治作业重点:果实锈壁虱和溃疡病发生盛期,第二代褐圆蚧、矢尖蚧和堆蜡粉蚧初龄幼虫的发生期,第二代卷叶蛾幼虫发生期。 相似文献
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扑虱灵防治柑桔矢尖蚧效果好扑虱灵25%可湿性粉剂是由江苏省江阴市农药二厂生产的防治水稻飞虱的特效药。其主要作用机制是抑制昆虫新表皮的形成,使昆虫不能正常完成生长发育过程而死亡、我们用此防治矢尖蚧取得良好效果。于矢尖蚧第一代若虫盛发期(5月下旬),结合... 相似文献
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矢尖蚧是我国杧果产区的重要害虫之一。通过田间和室内观测,调查矢尖蚧在杧果上的为害特点、各虫态主要特征、发生规律,以及设施大棚内9个杧果品种的矢尖蚧虫害发生程度。结果表明,矢尖蚧可为害杧果枝干、叶片和果实;雌虫经历2个若虫阶段和1个成虫阶段,雄虫经历2个若虫阶段、预蛹、蛹、成虫5个时期。金水仙杧和沙华绿杧的矢尖蚧为害程度最轻,桂热杧10号的为害程度最重;树冠下层为矢尖蚧为害最严重的部位,中层树冠次之,上层最轻或不受为害;第1代若虫孵化盛期为施药防治关键时期。 相似文献
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矢尖蚧全年一次性药剂防治试验 总被引:1,自引:0,他引:1
在矢尖蚧雌成蚧的不同发育阶段,柑桔不同物假期以及不同气候条件下,探讨实施该虫全年一次性药剂防治时,矿物油制剂与有机磷农药混用的适宜配方和喷布时期。结果表明,其最佳配方(体积比)是:40%氧化乐果乳油或40%水胺硫磷:95%机油乳剂:清水=1:60:3000。混配药液中基础物质机油乳剂的浓度必须保持在2%以上,而有机磷农药则可稀释3000倍,初步探明的最佳喷药时期是:矢尖蚧越冬代雌成蚧次年产卵末期,亦即当年第1代幼蚧虫口发生后峰期至终见期或第2代幼蚧发生的初期。也是柑桔第2次生理落果后期至果实膨大初期,一般正处于雨季节接近结束,高温干旱季节来临前,此时喷药能有效阻止幼蚧上果危害,较佳喷药时期为该虫越冬期,即采果后的11-12月,一般正值花芽分化前期,此时温度低湿度高,使用安全。 相似文献
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在矢尖蚧雌成蚧的不同发育阶段、柑桔不同物候期以及不同气候条件下,探讨实施该虫全年一次性药剂防治时,矿物油制剂与有机磷农药混用的适宜配方和喷布时期。结果表明,其最佳配方(体积比)是:40%氧化乐果乳油或40%水胺硫磷:95%机油乳剂:清水=1:60 :3000。混配药液中基础物质机油乳剂的浓度必须保持在2%以上,而有机磷农药则可稀释3000倍。初步探明的最佳喷药时期是:矢尖蚧越冬代雌成蚧次年产卵末期,亦即当年第1代幼蚧虫口发生后峰期至终见期或第2代幼蚧发生的初期,也是柑桔第2次生理落果后期至果实膨大初期,一般正处于梅雨季节接近结束、高温干旱季节来临前,此时喷药能有效阻止幼蚧上果危害。较佳喷药时期为该虫越冬期,即采果后的11~12月,一般正值花芽分化前期,此时温度低湿度高,使用安全。 相似文献
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Linking knowledge among spatial and temporal scales: Vegetation,atmosphere, climate and remote sensing 总被引:2,自引:0,他引:2
Global scale modeling is reviewed with respect to global circulation models, biosphere-atmosphere models, and climate-biosphere models. These different models focus on short to long time scale interactions between atmospheric and surface systems. Remote sensing is shown to play a central role in acquisition of data for these models, and an experiment, termed FIFE, is described, which is the first attempt to take simultaneous land surface observations of meteorological and biophysical parameters at sufficient resolution to test hypotheses linking the vegetated surface and circulation within the lower atmosphere. 相似文献
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在苹果园配备喷水设施,于冻害晚上提前喷水,花器冻害减少31.4%,皲皮减少27.6%,666.7 m^2产量增加502kg,收入增加1 255元. 相似文献
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Blowouts are the main features of aeolian activity in many dune areas. To assess the impact of future climatic change on the geomorphological processes prevailing in a dune landscape it is essential to understand blowout formation and identify the meteorological parameters which are important.The development, that is, local erosion and accumulation, of six blowouts in a dune terrain along the Dutch coast has been related to wind velocity and wind direction, as measured at a nearby standard meteorological station. Blowout changes correlate best with wind velocities between 6.25 and 12.5 m/s (measured at 10 m height) which are the critical wind velocities for moving particles in the 0.15 to 0.42 mm range. These winds mostly blow from the southwest. Consequently, the blowouts are elongated in the same direction.Extreme aeolian events such as northwestern storms have little effect on blowout development compared to events which have a lower magnitude but occur with a higher frequency. An eventual shift towards higher effective wind velocities would probably result not in larger blowouts but in a break-down of the whole system, especially if this shift were accompanied by a change in wind direction. The accumulation of sand in the blowouts during storms should be seen as a first step of adaptation to a higher energy level. 相似文献
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We describe the classification of landscapes characterised bymineral soil using a model that calculates soil moisture availability on amonthly basis. Scotland is used as a case study area. The model uses potentialsoil moisture deficit, estimated using broad scale (40 × 40 km)climate patterns, in conjunction with meteorological station measurements toobtain finer scale values of climatic soil moisture deficit. Point estimates ofsoil available water are obtained for soil characteristics using appropriatepedotransfer functions, and geostatistical techniques are used to upscale theresults and interpolate to a 1-km grid. Known heterogeneityin soil physical characteristics is used to provide local corrections to thepotential soil moisture deficit, estimated using the climatic variables above.Temporal profiles of monthly water content are modelled for each1-km location and classified into six classes usingunsupervised cluster analysis. The spatial distribution of these classesreflects regional variations in the availability of moisture and energy, onwhich finer-grained topographic patterns are superimposed. In the case study,the broad scale spatial heterogeneity of heathlands and grasslands on mineralsoils in Scotland is shown to be strongly related to the soil moistureclassification. The results can be used in studies investigating the patternsofdistribution of communities at the landscape and regional scale.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
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以山东省临邑县2000-2005年的气象资料和番茄晚疫病发生程度为基础,运用数据处理软件DIS分析了番茄晚疫病发生流行程度和气象因子间的关系,并建立了预测模型:Y=4.778 458+01315 706X5-0.023 627X6经检验历史符合率较高. 相似文献
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城市园林植保中存在的问题及应对策略 总被引:1,自引:0,他引:1
阐述目前城市园林植保存在的农药污染问题,分析城市园林植物生态环境以及园林害虫发生的特点,详细论述实施城市生态园林植保的基本策略。 相似文献