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1.
The olive is one of the most important crops in Greece as in many Mediterranean countries. Several insects are considered serious pests of the olive crop. In this study, we report two new pests for olive trees in Greece and possibly in the Mediterranean region: the quince moth Euzophera bigella (Zeller) (Lepidoptera: Pyralidae) and the olive leaf gall midge Dasineura oleae (F. Low) (Diptera: Cecidomyiidae). Although E. bigella is not considered a pest of olive trees, in the summer of 2011, the quince moth was recorded for the first time infesting olive trees in several orchards in the rural area of the Municipality of Amphipolis (Region of Central Macedonia). Infestation induced cracking and swelling symptoms on the bark of limbs and the periderm of trunks, accompanied by extensive internal bark necrosis, which caused the desiccation of limbs or even the death of whole trees. D. oleae has been reported infesting olive trees in Greece; however, it was not considered a pest of the crop. In February 2010, extensive infestations by D. oleae were detected in the coastal zone of Elounda, Lassithi (Region of Crete). Infestations were observed on the leaves causing elongate galls and deformations, while in highly infested trees defoliation was reported. Because of the scarceness of these infestations, the results reported in this study are discussed in relation to cases reported from other countries and/or on other crops. In addition, a review of the distribution, biology and control methods of these species is provided in an attempt to summarize the scattered information currently available.  相似文献   

2.
Summary Tests with Bromophos applied to stored grain in Yugoslavia Tests were made with Bromophos for controlling beetles infesting stored grain and for protecting non infested grain. Bromophos-emulsion (1g/qm) sprayed in empty stores always effected 100% mortality in beetles of generaTribolium, Oryzaephilus andCalandra. Bromophos proved to be more durable than Malathion, Lindan and DDVP, By using Bromophos-powder (1,2%; 100g/100kg = 12 ppm) wheat and maize were protected against grain pests. At the end of two months the mortality of beetles in wheat (in laboratory) amounted to 97–99%. In maize the effect lasted only two months.

Institut za Zaštitu Bilja, Yu 11 081 Beograd-Zemun, Nemanjina 6, P. O. Box 127, Jugoslawien.  相似文献   

3.
降香黄檀病虫害调查   总被引:6,自引:0,他引:6  
2009年5月,在广东省肇庆市国有林业总场属下的3个林场和2个苗圃基地调查降香黄檀病虫害,结果表明,降香黄檀人工林幼树的嫩梢和叶片都存在轻度病虫为害,未见严重的危险性病害。主要害虫是螟蛾类蛀梢害虫,主要病害是炭疽病和细菌性穿孔病。  相似文献   

4.
The effects of ploughing and previous crop on winter wheat pests and their natural enemies under an integrated farming system was investigated in an experimental area in Slovakia. The experiment consisted of 4 small plots (50?m2 each) to which both organic and inorganic fertilisers were applied. Moreover, there was one application of herbicide and a fungicide on each plot. The ploughing was either deep or shallow, and either silage-maize or pea was used as a previous crop. The effects of the ploughing and previous crop was studied by means of multivariate redundancy analysis (RDA) and subsequent Monte-Carlo permutation test. The results showed that there was a considerable temporal variation in the abundance of insect pests and their natural enemies. Of the two husbandry treatments, only ploughing caused significant difference in the composition and abundance of both pests and natural enemies. However, while most of the pests favoured deep ploughing, the majority of natural enemies occurred more abundantly on shallowly ploughed plots. The previous crop did not affect numbers of either pests or natural enemies. Two systems, integrated and organic, which have been surveyed previously, were mutually compared with respect to the abundance of insect pests. The organic farming system turned out to be more sustainable.  相似文献   

5.
In The Netherlands, insect pests on trees and shrubs are being monitored continuously since 1946. During these years, almost all insect pest populations showed marked changes, which may be the result of changes in forest management, shifts in forest composition, climate change and the arrival of new pests from the Mediterranean region or from other continents. In order to generate hypothesis about possible relationships between species ecology and environmental factors, we have analyzed 61 years of population development of the 98 most abundant species in the database while paying attention to life history traits and preferred host plants. The 22 species with infestations lasting a few years only were excluded from the analysis. Of the remaining 76 species, 18 were present over the entire observation period of 61 years. Of the other species, 27 showed a decline and 31 showed an increase. On coniferous trees most species showed decreasing populations. Increasing populations were found most on deciduous trees. Not directly climate-related factors such as changes in forest age, tree composition and forest management were identified as the most important causes for the fluctuations in pest insect populations. Climate change is a possible driver of the population increase in Thaumetopoea processionea, Haematoloma dorsatum and of the population decrease in Euproctis chrysorrhoea. The recently increasing exotic species Eupulvinaria hydrangeae and Pulvinaria regalis were exclusively found on trees in cities, presumably in relation to the higher temperatures of the urban habitat.  相似文献   

6.
Exploiting the principles of biological control of crop pests is an important management strategy for the resource-poor smallholder farmers of the tropics. The effects of nine hedgerow species on the abundance of major insect pests of beans and maize, and predatory/parasitic-arthropods were monitored over two cropping seasons and the intervening dry period. The tree/shrub species evaluated were Gliricidia sepium, Grevillea robusta, Senna siamea, Senna spectabilis, Flemingea congesta, Croton megalocarpus, Morus alba, Calliandra calothyrsus and Lantana camara. Arthropod abundance was monitored through counts of infested plants and using yellow pan and pitfall traps. Beanfly (Ophiomyia spp.) infestation was significantly higher in the presence of hedgerows (35%) than in their absence (25%). Hedgerows did not influence aphid (Aphis fabae) infestation of beans. In contrast, maize associated with hedgerows experienced significantly lower stalk borer (Busseola fusca and Chilo spp.) and aphid (Rhophalosiphum maidis) infestations than pure maize, the margin of difference being 13% and 11% respectively for the two pests. Ladybird beetles closely followed their prey, aphids, with significantly higher catches in sole cropped-plots than in hedgerow-plots and away from hedgerows. Activity of wasps was significantly greater close to hedgerows than away from them. Spider catches during maize season were 77% greater in the presence of hedgerows than in their absence, but catches during other seasons were similar between the two cropping systems. Differences among hedgerow species were not significant for most of the arthropods monitored, except that beanfly infestation was greater with Gliricidia hedgerows. The study indicates that the effect of hedgerows on pest infestations of crops and their role as refugia for predators cannot be generalized but depends on the specific arthropods.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

7.
The spectrum and dynamics of xylophagous insects infesting Pinus pinaster after a fire event were studied from November 2007 to December 2008 at Sierra de Outes (Galicia, NW Spain). Insects were collected within and outside the fire area. Relationships among species status, species abundance, tree parameters and tree injury were assessed. Mortality of injured trees was also recorded. Insect colonization built up consistently during the first year after the fire, although the pests did not colonize unburned trees in nearby areas. Thirteen insect species from six xylophagous families were collected. Tomicus spp., Buprestis novenmaculata, Anobium punctatum and Pissodes castaneus were the first species detected. Tomicus spp. (29%) and Ips sexdentatus (23%) were the dominant taxa. Bole char height and soil burn severity were positively correlated with insect presence. Trees with short stem diameter and thinner bark were also preferred. B. novenmaculata presence was positively correlated with crown scorch. Loss of cambium hydration was negatively related to the occurrence of pests, likely because sapwood desiccation and loss of nutrient impede brood development. About 33.3% of the fire-scorched pines died. The results recommend the removal of injured and dying pines after fire, to avoid the rise of pest population threatening recovering trees in the burned areas.  相似文献   

8.
The study was conducted throughout two seasons (2013 and 2014) at Xmatkuil farm at Merida, Yucatan, Mexico, to determine the relationships and the interactions between chemical compositions of condensed tannins and mimosine and their effects on the susceptibility of four Leucaena genotypes: Cunningham and K636 (L. leucocephala), and Nativa and KX2 (L. leucocephala × L. pallida) to the infestation of the most destructive insect pests; Leucaena Psyllids, Heteropsylla cubana Crawford, 1914 (Homoptera: Psyllidae), and Onion thrips, Thrips tabaci Lindeman, 1889 (Thysanoptera: Thripidae). Mimosine showed insignificant effect on the population of both pests. However, tannins exhibited a significant effect for Psyllid population on Nativa and K636, and highly significant effect on thrips for the same respective genotypes. The insignificant relationships of tannin effect were found for Cunningham and KX2 to the population fluctuations of Psyllid and Thrips.  相似文献   

9.
Port Orford cedar (Chamaecyparis lawsoniana) is endemic to northern California and southwestern Oregon and is considered a foundation species that plays critical roles in riparian areas and on nutrient‐poor soils. Since 1952, a non‐native, pathogenic oomycete (Phytophthora lateralis) has been spreading throughout the range of the cedar. Most spread occurs by vehicles carrying infested soil along gravel roads primarily used for timber harvest. In a previous study conducted in 1998 and 1999, Port Orford cedar and P. lateralis were censused in a 37‐km2 study area and dendrochronology was used to reconstruct the history of pathogen invasion. That work, which represents the only detailed analysis of spread rates for P. lateralis, showed that the first successful invasion into the study area took place in 1977 and that 43% of the susceptible host sites (stream crossings) were infested by 1999. In the work presented here, all sites that were uninfested in 1999 were re‐censused in 2012, extending the historical reconstruction of P. lateralis spread to 35 years. Two new infestations were initiated between 1999 and 2012, suggesting that the rate of spread of P. lateralis has slowed greatly. Between 1980 and 1989, the average number of new site infestations was 1.8 infestations per year, while between 1990 and 1999 the average was 0.4 infestations per year and between 2000 and 2009 the average was 0.2 infestations per year. Several potential explanations for the reduced number of new infestations are discussed.  相似文献   

10.
Adelgids (Hemiptera) in the genus Pineus have been reported as introduced insect pests causing serious losses to Pinus plantations worldwide. In 2008, Pineus boerneri was recorded for the first time in Colombia, with infestations noted on Pinus kesiya, P. tecunumanii, P. maximinoi and P. oocarpa. The lack of information on this insect in Colombia prompted investigations of its life cycle and infestation levels as well as host susceptibility of the main Pinus species planted in Colombia. In addition, the possibility of using a Ceraeochrysa species, an already established predator of adelgids in Colombia, for biological control was considered. Results showed that Pineus boerneri in Colombia has an anholocyclic life cycle comprised of four instars with a complete duration of between 49 and 97 d. Infestations were higher in the middle and upper part of trees. Pinus kesiya and P. maximinoi had the highest levels of susceptibility in field as well as in greenhouse trials. A survey of naturally infested trees showed P. tecunumanii to be moderately susceptible, whereas P. patula and P. oocarpa had low levels of susceptibility in a greenhouse trial but were not susceptible in the field. Investigations considering the impact of predation of Ceraeochrysa species showed a high predation rate of up to 140 P. boerneri consumed per day by a single Ceraeochrysa individual. Other predators of P. boerneri were recorded but were not sufficiently common to warrant detailed study.  相似文献   

11.
Agroforestry trees are attacked by a wide spectrum of insects at all stages of their growth just like other annual and perennial crops. Pest management in agroforestry has not received much attention so far, but recent emphasis on producing high value tree products in agroforestry and using improved germplasm in traditional systems, and emergence of serious pest problems in some promising agroforestry systems have increased awareness on risks posed by pests. Insects may attack one or more species within a system and across systems in the landscape, so pest management strategies should depend on the nature of the insect and magnitude of its damage. Although greater plant diversity in agroforestry is expected to increase beneficial arthropods, diversity by itself may not reduce pests. Introduction of tree germplasm from a narrow genetic base and intensive use of trees may lead to pest outbreaks. In simultaneous agroforestry systems, a number of factors governing tree—crop—environment interactions, such as diversity of plant species, host range of the pests, microclimate, spatial arrangement and tree management modify pest infestations by affecting populations of both herbivores and natural enemies. Trees also affect pest infestations by acting as barriers to movement of insects, masking the odours emitted by other components of the system and sheltering herbivores and natural enemies. In sequential agroforestry systems, it is mostly the soil-borne and diapausing insects that cause and perpetuate damage to the common hosts in tree—crop rotations over seasons or years. An integrated approach combining host-plant resistance to pests, exploiting alternative tree species, measures that prevent pest build up but favour natural enemies and biological control is suggested for managing pests in agroforestry. Species substitution to avoid pests is feasible only if trees are grown for ecological services such as soil conservation and low value products such as fuelwood, but not for trees yielding specific and high value products. For exploiting biological control as a potent, low cost and environmentally safe tool for pest management in agroforestry, research should focus on understanding the influence of ecological and management factors on the dynamics of insect pest-natural enemy populations. Scientists and policy makers in national and international institutions, and donors are urged to pay more attention to pest problems in agroforestry to harness the potential benefits of agroforestry.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

12.
Summary Most of the crops in Southern Somalia suffer from a heavy attack of insect pests. Contrary, the importance of diseases is in general less at least during the dry seasons. This was stated during a survey of the author in 1963. Bananas are infested by scale insects, especiallyAspidiotus destructor and white grubs (Schizonycha spp.) which damage the roots. The so-called sigatoka disease shows some importance on certain varieties. The stainer bugDysdercus cardinalis and the bollwormsPlatyedra gossypiella andDiparopsis watersi are major pests of cotton. Numerous other cotton pests were not very harmful during the time of the survey. Maize proved to be badly attacked by stemborers mainly the pyralid mothChilo zonellus. The same species plays an important part as a pest of sorghum where it is frequently associated withSesamia cretica. The weaver birdQuelea quelea aethiopica causes damage in certain areas during the wet seasons. Among the sorghum diseases,Sphacelotheca spp. andTolyposporium spp. are important. Sugarcane is attacked by the mealy bugSaccharicoccus sacchari. The pyralid mothAntigastra catalaunalis is a very common pest of sesame. Major diseases of the same crop are caused by a leafcurl virus and the bacteriumXanthomonas sesami. Roots and pods of groundnuts are infested by the mealy bugDysmicoccus brevipes. Coconut palms suffer from the damage of rhino beetles (Oryctes monoceros) and scale insects (Aspidiotus destructor). Citrus shows mostly a heavy infestation by scale insects (Parlatoria spp.,Lepidosaphes spp.) and aphids (Toxoptera aurantii). The same applias to guava and sweet sop. Mealy bugs and other scale insects suck in considerable numbers on the fruits and other parts of these plants. Spider mites are important pests of papaya leaves which are also infested on many localites by a mildew disease. Among the vegetables, tomatoes show frequently an infestation by a very harmful leafcurl virus.   相似文献   

13.
安吉竹种园病虫害及防治初报   总被引:3,自引:0,他引:3  
安吉竹种园竹林面积集中,竹类品种多,出笋延续时间长,病虫害种类多而且活动规律复杂,通过1997-1999年的防治工作,初步掌握了为害竹林的病虫害的种类及活动规律,摸索础有效的防治方法,取得了明显的效果。  相似文献   

14.
2009~2011年,采用平行取样法,在广西钦州康熙岭红树林自然保护区无瓣海桑纯林内,对无瓣海桑主要害虫及其寄生性天敌进行调查,分叶部、枝梢及蛀干害虫,按轻、中、重3级划分危害程度,结果表明,在研究地调查收集到无瓣海桑害虫种类共4目13科21种,其中绿黄枯叶蛾、木麻黄枯叶蛾、迹斑绿刺蛾、白囊袋蛾和荔枝茸毒蛾是无瓣海桑的主要害虫,均为食叶类害虫。并收集了危害无瓣海桑较严重的绿黄枯叶蛾及木麻黄枯叶蛾的寄生性天敌,共2目4科8种,其中绿黄枯叶蛾卵的寄生蜂,寄生率达67.3%。因此,保护和利用天敌是无瓣海桑害虫防治的有效方法。  相似文献   

15.
河北省黄连木病虫害发生现状及防治技术   总被引:3,自引:0,他引:3  
2006--2008年,调查了河北省黄连木病虫害发生情况,结果发现河北省危害黄连木的主要害虫有黄连木种子小蜂、黄连木尺蛾、黄连木梳齿毛根蚜、缀叶丛螟、刺蛾类(黄刺蛾、褐边绿刺蛾)等;病害主要有炭疽病、苗木立枯病等,并针对这些病虫害种类提出了具体的防治方法。  相似文献   

16.
竹林害虫综合防治中营林技术作用探讨   总被引:1,自引:0,他引:1  
在竹林害虫综合防治中,营林措施有着重要的作用。研究结果表明,通过劈山、松土、垦复、施肥和清理病虫次竹等营林措施,使遭受目标害虫严重为害的残败竹林恢复长势,挽回损失;增强了竹林对害虫的忍受和自控能力;改善了竹林生态环境,破坏了害虫的越冬场所,压低了翌年虫口发生基数;清除了某些害虫的产卵场所和中间寄主,直接压低了虫口。  相似文献   

17.
湖南西部大叶黄杨主要病虫种类及流行规律   总被引:4,自引:0,他引:4  
2000—2002年以湖南怀化市、张家界市、吉首市为基点对大叶黄杨主要病虫害发生情况进行了调查采集和分类鉴定,查清了危害大叶黄杨的主要害虫20种,病害4种,并对成灾性及常发性病虫害的发生流行规律进行了调查。  相似文献   

18.
With the expected rising temperatures, outbreaks of insect pests may be more frequent, which can have large consequences on forest ecosystems and may therefore negatively affect the forestry sector. In order to be better able to predict where, but not if, outbreaks may occur in future we investigated the potential future (2070) geographical distribution of 30 prospective insect pest species (Coleoptera and Lepidoptera) by applying species distribution modelling. We also assessed the geographical extent to which the boreal forest in Sweden may be affected. We found that numerous species may experience large increases in their potential distribution in future, which may result in outbreaks in “new” areas. It is therefore likely that more trees will be infested by pests in future, which may have large implications for the Swedish forestry sector.  相似文献   

19.
对广东省藜蒴病虫害种类和发生情况进行调查,共发现病害6种、虫害21种;初步确定了藜蒴主要病虫害种类为黎蒴枝枯病、黎蒴小蠹虫、英德跳虫脩、黎蒴榉祥蚧,危害严重时均可导致黎蒴死亡。介绍了4种主要病虫害的危害特点,并提出了相应的防治建议。  相似文献   

20.
The dwellers of ancient Egypt (km't*) have left in their tombs, paintings and papyri an immeasurable legacy of information concerning their religion, writing, language, agriculture, food storage and pest control. Several insect species (belonging to the families Anobiidae, Braconidae, Cleridae, Curculionidae, Cyclorrhapha, Dermestidae, Phycitidae, Ptinidae and Tenebrionidae) were found in the corpses (kha't) as well as the food offerings (pert er kheru) given to the deceased, which have been buried in predynastic (~4500–2900 B. C.) and dynastic tombs (~2900 B. C. –395 A. D.). These funerary insects witness the early occurrence of necrophagous and graminivorous pests infesting human and animal corpses as well as stored food offerings. Such infestations by harmful intruders may represent one of the first traceable links between insects and man in history. The understandable anxiety of the priests that tombdefiling insects (apshait) may injure the mummified body of the dead, is expressed in chapter 36 of the Book of the Dead (XVIII.–XXII. Dynasty), used as a manual of instructions for the resurrected deceased (aakhu) in the underworld (duat). It is understood that the ancient Egyptians were not able to foresee that extensive employment of spacious stores stuffed with food supplies will attract 2–3 dozens of insect species and provide them with vast amounts of desiccated seeds, plant and animal tissues. The insects thus gained optimal conditions for their propagation and rapid build-up of dense pest populations. The country-wide use of large granaries and other food stores can be regarded as an early historical incidence interfering with the natural equilibrium among insects and man. The insect species breeding in desiccated cereals and other foodstuffs stored in ancient Egypt have probably originated from ancestors which prevailed in specific natural habitats (where they may be found also at present). The shift of those insect species from natural habitats to the storage environment was probably promoted by the ability of the former to live in storage buildings and utilize desiccated and partly nutrient-deficient foodstuffs—owing to their efficient water conservation, microbial supplementation of lacking nutrients, adaptation of their reproductive behaviour to reduced space and illumination as well as due to employment of a larval diapause in response to adverse conditions.  相似文献   

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