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Common Reed (common + reed)
Selected AbstractsRemarks on the morphology and biology of Cleigastra apicalis (Meigen, 1826) (Diptera, Scathophagidae)ACTA ZOOLOGICA, Issue 4 2006Maria Grochowska Abstract The egg, second- and third-instar larvae and puparium of Cleigastra apicalis are described for the first time. All pre-imaginal stages are found on stems of the common reed affected by flies of the genera Lipara and Platycephala and the butterfly Arenostola phragmitidis. The larvae feed on dead plant and animal tissue and the excreta of other insects that live inside the stems of the common reed. Exceptionally they will scrape living plant tissue. The pupa is the overwintering stage. [source] Can late summer Landsat data be used for locating Asian migratory locust, Locusta migratoria migratoria, oviposition sites in the Amudarya River delta, Uzbekistan?ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2008Ramesh Sivanpillai Abstract Existing survey methods for assessing the Asian migratory locust, Locusta migratoria migratoria L. (Orthoptera: Acrididae), infestation risk in the Amudarya River delta, Uzbekistan, are largely constrained by economic resources and site accessibility. The surveys are restricted to a few easily accessible areas, which leads to a misinterpretation of the threat of locust infestation. This often results in indiscriminate blanket treatments of vast areas of wetlands with broad-spectrum insecticides, which may adversely impact non-target fauna and flora. In order to minimize the bias during surveys, one approach would be to allocate the sampling locations based on the distribution of the primary food and shelter plant of the locusts, the common reed, Phragmites australis (Cav.) Trin. ex Steud (Poaceae). In this study, we evaluated the utility of satellite-based remotely sensed data (Landsat TM) acquired in August 2006 to characterize reed distribution in the delta and identify potential locust oviposition sites. The overall accuracy of the Landsat data to map land cover classes in the delta was 84%. The Landsat TM data identified 90% of the reeds, but it was less useful in identifying areas where other vegetations (shrubs and grasses) were mixed with reeds. During the following summer field survey in June 2007, we identified 37 sites that were infested with early-instar locusts. The low migration capacity of young nymphs in dense reed vegetation allowed us to presume that these sites were used for oviposition in the previous summer. Twenty-eight (74%) of these 37 sites had reeds in the previous year. Results from these studies demonstrate that reed distribution maps derived from satellite data could be used for targeting locust egg-pod survey locations, in order to minimize sampling bias while predicting locust infestation risks for the following season. [source] Seasonal population changes of five parasitoids attacking the scale insect Nipponaclerda biwakoensis on the common reed, with special reference to predation by wintering birdsENTOMOLOGICAL SCIENCE, Issue 4 2005Shuji KANEKO Abstract Seasonal changes in the abundance of five species of hymenopterous parasitoids (four species of Encyrtidae and one species of Eulophidae) attacking the scale insect Nipponaclerda biwakoensis on the common reed were investigated for 2 years in Lake Biwa, with special reference to predation by the reed bunting, Emberiza schoeniclus, during winter. The scales settled on reed shoot stems under sheath leaves, passing through three discrete generations per year. The abundance of adult female scales increased exponentially from July (first generation) to December (third generation). Adult female scales of the third generation overwintered on reed shoots. During winter, female scale abundance dramatically declined, whereas the number of predation marks made by reed buntings using their bills on reed sheath leaves increased. The generations of all five parasitoids were synchronized with the host scale generations, and the five parasitoids overwintered as larvae inside the scale bodies. The abundance of parasitized scales and parasitoid adults emerging from the scales also increased from July to December, but greatly decreased during winter. The overall parasitism rate of the female scales remained at relatively low levels (less than 40%) throughout the year, including before and after winter. A bird exclusion experiment revealed that the dramatic winter decrease of the abundance of the scale and its five parasitoids was due to intensive and non-selective predation by the buntings on unparasitized and parasitized scales. Additionally, the proportion of immature parasitoids removed by birds varied between the five parasitoid species. Thus, seasonal population changes of the five scale parasitoids are considerably affected by bird predation on overwintering immature parasitoids. [source] Spatio-temporal pattern of Pentastiridius leporinus migration in an ephemeral cropping systemAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2010Alberto Bressan 1Cixiid planthoppers (Hemiptera: Fulgoromorpha: Cixiidae) are considered to be important economic pests because of their ability to transmit phloem-restricted prokaryotes causing emerging plant diseases worldwide. However, little information is available on the biology and ecology of such species. This is the case for Pentastiridius leporinus (Linnaeus), a cixiid planthopper reported to live on common reed across Countries of Central and Northern Europe. However, in the east of France, the same planthopper species appears to complete its life cycle in the sugar beet-wheat cropping system and has been repeatedly shown to transmit prokaryotic plant pathogens that are associated with an emerging disease of sugar beet called syndrome ,basses richesses'. 2To gather evidence on the biology of the planthopper in the cropping rotation, we analysed the flight activity of adults. We used transparent sticky traps for sampling migrating adults and quantified nymphs as well as emerging adults on the roots of wheat plants. 3Results showed a significant correlation between disappearance of nymphs and emerging adults from wheat roots and the occurrence of migrant adults in nearby sugar beet fields. Planthoppers migrated more abundantly and colonized sugar beet for longer periods than any other crop available. Flight activity was very pronounced during the migratory phase that was extended from the middle of June to the middle of July. A geographic information system and geostatical analysis revealed that planthoppers flew and colonized the centre of the sugar beet field rather than the borders. 4Overall, results obtained in the present study suggest that the ecology and biology of the planthopper vector in the cropping rotation is a primary factor that leads to the emergence of the syndrome ,basses richesses' disease of sugar beet. [source] Microsatellite variation within and among North American lineages of Phragmites australisMOLECULAR ECOLOGY, Issue 7 2003K. Saltonstall Abstract Over the past century, the spread of the common reed (Phragmites australis) has had a dramatic impact on wetland communities across North America. Although native populations of Phragmites persist, introduced invasive populations have dominated many sites and it is not clear if the two types can interbreed. This study compares patterns of differentiation in 10 microsatellite loci among North American and European Phragmites individuals with results obtained from sequencing of noncoding chloroplast DNA. Three population lineages (native, introduced and Gulf Coast) were previously identified in North America from chloroplast DNA and similar structuring was found in the nuclear genome. Each lineage was distinguished by unique alleles and allele combinations and the introduced lineage was closely related to its hypothesized source population in Europe. Size homoplasy and diagnostic base substitutions distinguishing lineages were evident at several loci, further emphasizing that native, introduced and Gulf Coast North American Phragmites lineages are genetically distinct. Gene flow between lineages was low and invasive introduced populations do not represent a hybrid population type. [source] | ||||||||||