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Epidemiology, Aphid Vectors, Impact and Management of Tobacco Etch Potyvirus in Hot Peppers in JamaicaMcDonald, Sharon Angella 22 March 2001 (has links)
Production of hot peppers, Capsicum spp., in Jamaica is constrained by the aphid-transmitted potyviruses, tobacco etch virus (TEV) and potato virus Y (PVY). The virus epidemiology was not understood and no effective virus management system existed for these viruses. This study sought to identify possible management strategies for aphid-transmitted viruses of hot peppers in Jamaica, using TEV and Capsicum chinense, var. 'Scotch Bonnet' and 'West Indian Red', as models.
Field spread of TEV to pepper was mainly by secondary spread from primary infections. Secondary infections were spatially correlated to primary infections for up to 25 meters. Natural infections of TEV were associated with aphid flight activity. Over 30 species of aphids were collected on pepper farms in St. Catherine parish. These aphids included five known vectors of TEV, Aphis gossypii Glover, A. craccivora Koch, A. spiraecola Patch, Lipaphis erysimi Hille Ris Lambers and M. persicae (Sulzer), and 12 new records for Jamaica, Aphis amaranthi Holman, Brachycaudus helichrysi (Kaltenbach),Capitophorus hippophaes (Walker), Geopemphigus floccosus (Moreira), Hysteroneura setariae (Thomas), Lipaphis erysimi Hille Ris Lambers, Rhopalosiphum padi (Linnaeus), Schizaphis graminum (Rondani), Schizaphis rotundiventris (Signoret), Trichosiphonaphis poligoni (van der Goot), Uroleucon ambrosiae complex (Thomas) and Uroleucon pseudoambrosiae (Olive). A. amaranthi and U. ambrosiae were associated with TEV spread. Weeds on and near farms influenced the abundance and species of aphids captured.
West Indian Red pepper showed tolerance to TEV. Scotch Bonnet pepper yield reduction was greater if plants were infected with TEV during the vegetative stage through flower initiation rather than after the start of fruit set. Stylet oil and reflective mulch used together delayed the incidence of TEV in pepper plots for over two months. TEV management programs should aim to delay the virus from infecting peppers during the first two months after transplanting. A risk analysis is proposed for management of TEV and other aphid-borne viruses. / Ph. D.
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Variação sazonal e a influência da estrutura da paisagem na ocorrência de Charadriidae e Scolopacidae no litoral do Rio Grande do SulScherer, Angelo Luís 25 February 2010 (has links)
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Previous issue date: 25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O Brasil é visitado anualmente por milhares de aves costeiras que realizam movimentos sazonais da América do Norte para a América do Sul e vice-versa. Destacam-se as que vêm no norte com a aproximação do inverno boreal que chegam à procura de locais de parada e invernada, onde encontram alimentação farta, propiciando-lhes a continuidade do seu ciclo de vida. O presente trabalho tem por objetivo contribuir com o conhecimento a respeito da variação sazonal e influência da paisagem na ocorrência de aves costeiras ao longo do litoral médio na planície costeira do Rio Grande do Sul, Brasil. O trabalho é apresentado através de dois artigos que tratam dos temas propostos, estando formatado em uma versão preliminar de acordo com as normas de submissão da revista científica Journal of Ornithology. O primeiro artigo apresenta dados referentes à ocorrência e a variação sazonal de aves costeiras das famílias Charadriidae e Scolopacidae ao longo de 120 Km de praia durante um período de dois anos evidenciando a importância / The coast of Rio Grande do Sul State, Brazil, includes a remarkable number of habitats used by many Nearctic shorebirds species during the non-breeding season in the
austral summer months. During two years we evaluated the abundance of shorebird monthly, along 120 km of the beach in Rio Grande do Sul, southern Brazil. Of the 17 species
recorded, the most abundant were the Sanderlings (Calidris alba), White-rumped Sandpiper (Calidris fuscicollis) and Red Knot (Calidris canutus). The highest abundance occurred
between October and April, and the lowest abundance occurred between May and September. Of the total species, 14 were migrant shorebirds from north hemisphere, one is a
migrant shorebird from south hemisphere and two were resident. Some species were present throughout the year. Nine species were constantly registered, two were sporadic and six were incidental recorded. This study confirms that the beaches of Rio Grande do Sul State, are an important migration stopover and winter site for many shorebir
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Distribuição espacial e temporal de aves limícolas (Charadriiformes) na Ilha dos Caranguejos, Golfão Maranhense, Brasil / Spatial and temporal distribution of shorebirds (Charadriiformes) in Crab Island,Gulf of Maranhao, BrazilCarvalho, Dorinny Lisboa de 12 December 2008 (has links)
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Previous issue date: 2008-12-12 / PETRÓLEO BRASILEIRO S.A. / We studied spatial and seasonal distribution of shorebirds (Charadriiformes) in Island of
Caranguejos, Gulf of Maranhão. Censuses were conducted seasonally (considering arrival of
migrants in South America, wintering, departure and breeding in North America) from
September/2007 to July/2008, in two sectors of Island, North and South. We used the methods of
point count, transect and estimate. The North Sector showed greater richness, the South, most
abundance. The North Sector did not show differences in number of individuals or significantly
different (Kruskal-Wallis, H = 1.0163, df = 3, P = 0.7973) between the periods. The Southern
Sector showed greater abundance in the arrival (35,046) winter (35,708), decline in departure
(20,046) and increasing of abundance in reproductive period (92), showed no significantly
different (Kruskal-Wallis , H = 4.1596, df = 3, P = 0.2447). Considering the total number of
shorebirds, the following pattern was observed: high abundance during the period of arrival
(46,698), and winter (41,263), followed by declines in the individuals numbers in departure
(24,169) and reproductive (6071), not significantly different (Kruskal-Wallis, H = 28,892, df = 3,
P = 0.4090). There was no significantly different considering the abundance of time of arrival
(Mann-Whitney U = 44.00; Z = 0.7107, P = 0.4773), winter (Mann-Whitney U = 48.50; Z =
0.3909 P = 0.6959), departure (Mann-Whitney U = 38.00; Z = 11,371, P = 0.2555) and
reproductive (Mann-Whitney U = 45.00; Z = 0.6396, P = 0 , 5224) between North and South.
Temporal distribution showed a high abundance in the months September to November (autumn
migration) and from December to February (winter) reducing the number of individuals in the
months of March to May and low values were recorded from June to August, when the birds are
breeding in Arctic. Calidris pusilla was the most abundant species in all periods. Spatial
distribution was related to the change of tide. Island of Caranguejos is a important wintering site
for migratory shorebirds, its conservation is important for maintenance of birds group in wild life. / Objetivou-se descrever a distribuição espacial e temporal de aves limícolas
(Charadriiformes) na Ilha dos Caranguejos, Golfão maranhense. Os censos foram realizados
sazonalmente (considerando a chegada dos migrantes na América do Sul, invernada, partida e
reprodução na América do Norte) de setembro/2007 a julho/2008 em dois setores da Ilha,
denominados Norte e Sul. Utilizou-se os métodos de ponto fixo, transecto e estimativa. O Setor
Norte apresentou maior riqueza, o Sul, maior abundância. O Setor Norte não mostrou diferenças
nítidas no número de indivíduos nem diferença significativa (Kruskal-Wallis, H= 1,0163; gl= 3;
P= 0,7973) entre os períodos. O Setor Sul apresentou maior abundância no período de chegada
(35.046) e invernada (35.708), com declínio no período de partida (20.046) e elevando o número
de indivíduos no período reprodutivo (92), não mostrando diferença significativa (Kruskal-
Wallis, H= 4,1596; gl= 3; P= 0,2447). Considerando o número total de aves limícolas, se deu o
seguinte padrão: alta abundância no período de chegada (46.698) e invernada (41263), seguida
por declínios nos números de indivíduos nos períodos de partida (24.169) e reprodutivo (6.071),
não houve diferença significativa (Kruskal-Wallis, H= 28,892; gl= 3; P= 0.4090). Não houve
diferença significativa da abundância considerando os períodos de chegada (Mann-Whitney U=
44,00; Z= 0,7107; P= 0,4773), invernada (Mann-Whitney U= 48,50; Z= 0,3909; P= 0,6959),
partida (Mann-Whitney U= 38,00; Z= 11,371; P= 0,2555) e reprodutivo (Mann-Whitney U=
45,00; Z= 0,6396; P= 0,5224) entre os setores Norte e Sul. A distribuição temporal mostrou alta
abundância nos meses setembro a novembro (migração de outono) e dezembro a fevereiro
(invernada) diminuindo o número de indivíduos nos meses de março a maio e baixos valores nos
meses de junho a agosto quando as aves estão se reproduzindo no Ártico. Calidris pusilla foi a
espécie mais abundante em todos os períodos. A distribuição espacial se deu de acordo com a
variação de maré. A Ilha dos Caranguejos se mostrou como um importante sítio de invernada de
aves limícolas migratórias, sendo fundamental a conservação dessa área para a manutenção desse
grupo de aves na vida silvestre.
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The temporal distribution and relative abundance of stable flies (Stomoxys calcitrans) (Diptera: Muscidae) in a feedlot near Heidelberg, Gauteng, South Africa / Maria Magdalena EvertEvert, Maria Magdalena January 2014 (has links)
The stable fly, Stomoxys calcitrans (L.) is a haematophagous fly that feeds primarily on the
forelegs of cattle stimulating a range of avoidance behaviours in confinement situations such as
feedlots. From literature it is apparent that stable flies associated with feedlots have a significant
impact on cattle especially with regard to economic parameters such as a decline in feed intake
and thus a lower average daily gain resulting in less meat production due to irritation caused by
painful bites. The abundance of the stable flies was studied in a large commercial feedlot near
Heidelberg from October 2012 to September 2013. Two tsetse fly traps, namely the NZI and the
Vavoua fly traps, were used and evaluated in determining the seasonal abundance of the stable
flies. The tsetse traps proved to be most effective for sampling stable flies compared to other
designs. The NZI and Vavoua tsetse type trap were compared and although there were no
significant difference the NZI trap proved to be more reliable and user friendly for this study.
Stable flies were more abundant from late December with a peak in numbers late in January
through February and became less abundant from early March. Minimum to no fly abundance
occurred in the winter months from May to June 2013. The data indicated a strong edge effect
for the stable flies, the flies were more abundant in pens and corridors that were surrounded by
vegetation, manure run off and holding ponds. The numbers collected in traps were correlated
with stable fly counts on the cattle to be used in calculating a future threshold in chemical
control. Preliminary observations on the influence of temperature, wind speed and rainfall were
also made. This research will form part of a larger project to determine an integrated fly
management program for the feedlot. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014
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The temporal distribution and relative abundance of stable flies (Stomoxys calcitrans) (Diptera: Muscidae) in a feedlot near Heidelberg, Gauteng, South Africa / Maria Magdalena EvertEvert, Maria Magdalena January 2014 (has links)
The stable fly, Stomoxys calcitrans (L.) is a haematophagous fly that feeds primarily on the
forelegs of cattle stimulating a range of avoidance behaviours in confinement situations such as
feedlots. From literature it is apparent that stable flies associated with feedlots have a significant
impact on cattle especially with regard to economic parameters such as a decline in feed intake
and thus a lower average daily gain resulting in less meat production due to irritation caused by
painful bites. The abundance of the stable flies was studied in a large commercial feedlot near
Heidelberg from October 2012 to September 2013. Two tsetse fly traps, namely the NZI and the
Vavoua fly traps, were used and evaluated in determining the seasonal abundance of the stable
flies. The tsetse traps proved to be most effective for sampling stable flies compared to other
designs. The NZI and Vavoua tsetse type trap were compared and although there were no
significant difference the NZI trap proved to be more reliable and user friendly for this study.
Stable flies were more abundant from late December with a peak in numbers late in January
through February and became less abundant from early March. Minimum to no fly abundance
occurred in the winter months from May to June 2013. The data indicated a strong edge effect
for the stable flies, the flies were more abundant in pens and corridors that were surrounded by
vegetation, manure run off and holding ponds. The numbers collected in traps were correlated
with stable fly counts on the cattle to be used in calculating a future threshold in chemical
control. Preliminary observations on the influence of temperature, wind speed and rainfall were
also made. This research will form part of a larger project to determine an integrated fly
management program for the feedlot. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014
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BASES PARA LA GESTIÓN INTEGRADA DE PEZOTHRIPS KELLYANUS (BAGNALL) (THYSANOPTERA: THRIPIDAE) EN CÍTRICOSPlanes Insa, Laura 10 August 2016 (has links)
[EN] Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) is a new citrus pest in the Mediterranean basin. Nymphs of P. kellyanus refuge and feed on the surface of young fruitlets. This feeding habit causes rings of tissue scar around the apex as fruit mature and leads to economic losses because of the reduced market value of the affected fruit.
Despite the worldwide distribution and economic importance of P. kellyanus, its biological control is still under development and chemical control is the only alternative for growers. In order to improve the integrated management of P. kellyanus we determined the seasonal trend of P. kellyanus nymphs during the period in which the young fruitlets are sensitive to thrips damage. We studied the diurnal distribution of ¿rst and second generation P. kellyanus nymphs, as well as, the spatial distribution within the tree of the nymphs and damages. These results will improve the sampling protocols and the insecticide applications. The seasonal trend (number of generations attacking the fruit) and damages of P. kellyanus nymphs depended on the orchards and years. This result emphasizes the importance of sampling weekly from petal until six weeks later. Furthermore, according to the data obtained, when there is a second generation of P. kellyanus nymphs, this is generally more damaging.
Pezothrips kellyanus nymphs showed a clear preference for fruit located at the top of the trees, which coincided with the highest percentage of damaged fruit in this area. P. kellyanus nymphs were uniformly distributed and the cardinal directions and time of day does not seem to be an important factor to develop a sampling plan or to spray insecticides.
The next objective was to determine the efficacy of three insecticides (chlorpyrifos, spinosad and spirotetramat) to control P. kellyanus nymphs. These insecticides were selected because of their different mode of action. Chlorpyrifos and spinosad significantly reduced the percentage of damaged fruit when there was one generation of nymphs. However, their persistence was not enough to prevent the attack of a second generation of nymphs. Spirotetramat had not a shock effect against this pest and it could not avoid the attack of a second generation. We analysed the side effects of these three insecticides on natural enemies present at the time of the treatment. Spinosad as spirotetramat negatively affected phytoseiids. Due to low populations of other natural enemies we could not assess the side effects on them. Therefore, we decided to study the side effects of these insecticides on coccinelids and parasitoids under laboratory conditions.
Lethal and sublethal side effects of spirotetramat on adults and larvae of Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) were evaluated under laboratory conditions by topical application and by ingestion of treated individuals of Planococcus citri Risso (Hemiptera: Pseudococcidae). Spirotetramat resulted harmless when directly applied on larvae and adults of C. montrouzieri, since it did not affect survival, longevity, fecundity, egg hatching, and offspring survival. When larvae and adults of C. Montrouzieri were fed with treated prey, spirotetramat was also classified as harmless.
We studied lethal and sublethal effects of spirotetramat, spinosad and chlorpyrifos on Aphytis melinus DeBach (Aphelinidae Hymenoptera), the main parasitoid of Aonidiella aurantii (Maskell) (Hemipteta: Diaspididae). For A. melinus adults, chlorpyrifos and spinosad were classified as toxic but spirotetramat resulted moderately toxic. For immature (larvae), chlorpyrifos was moderately toxic, spirotetramat was slightly toxic and spinosad resulted harmless. Takin into consideration these results, spirotetramat could be used against P. kellyanus in orchards where population levels are low and an application against A. aurantii is also need because this insecticide shows high efficacy against this pest. / [ES] Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) es actualmente una plaga más en los cítricos valencianos, cuyas ninfas, al alimentarse de la superficie de los frutos recién cuajados, producen unas escarificaciones circulares alrededor del pedúnculo que devalúan el valor del fruto en el mercado.
Hoy en día, el control químico es prácticamente la única alternativa contra este trips. Para mejorar la gestión integrada de P. kellyanus es necesario un mayor conocimiento sobre su biología y ecología en campo. Para ello, se ha seguido la dinámica poblacional de las ninfas de P. kellyanus durante el periodo en que los frutos recién cuajados son más sensibles a los daños producidos por las ninfas. Se ha estudiado la distribución de la plaga dentro de los árboles y su movimiento a lo largo del día, factores necesarios para estimar la población de trips y para afinar las aplicaciones de productos fitosanitarios. Tanto la dinámica como los daños variaron según parcelas y años. Tras la caída de pétalos se observaron una o dos generaciones de ninfas que produjeron daños en los frutos. Resultado que subraya la necesidad de realizar muestreos semanales desde la caída de pétalos hasta incluso después del tratamiento contra la primera generación. Además, según los datos obtenidos, cuando se da una segunda generación de P. Kellyanus, ésta es más dañina para los frutos. Las ninfas de P. kellyanus mostraron una preferencia por los frutos situados en la parte alta de la copa, coincidiendo con el mayor número de frutos dañados en esta zona. La distribución de las ninfas fue uniforme en las cuatro orientaciones del árbol y a lo largo del día. Por lo tanto, estos factores no parecen ser claves a la hora de desarrollar un plan de muestreo o realizar aplicaciones fitosanitarias.
A continuación se determinó la eficacia de tres insecticidas (clorpirifos, spinosad y spirotetramat), con diferente modo de acción, en el control de las ninfas de P. kellyanus. Clorpirifos y spinosad redujeron significativamente el porcentaje de frutos dañados cuando se dio una sola generación de ninfas P. Kellyanus, sin embargo no evitaron el ataque de una segunda generación de ninfas. Spirotetramat no presentó un efecto de choque y no evitó el segundo ataque. En estos trabajos de campo, se analizaron los efectos secundarios de los insecticidas sobre los enemigos naturales presentes en el momento de los tratamientos. Spinosad como spirotetramat afectaron negativamente a las poblaciones fitoseidos en campo. Debido a las bajas poblaciones del resto de enemigos naturales no pudo evaluarse los efectos secundarios sobre ellos y se estudiaron en condiciones de laboratorio sobre coccinélidos y parasitoides.
Se determinaron los efectos letales y subletales de spirotetramat en adultos y larvas de Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae), por aplicación directa de los productos y por ingestión de presa, Planococcus citri Risso (Hemiptera: Pseudococcidae), previamente tratada por los productos. Spirotetramat resultó inocuo al aplicarse directamente sobre larvas o adultos de C. montrouzieri, y no afectó a la supervivencia, longevidad fecundidad, fertilidad y y supervivencia de la descendencia. Spirotetramat también resultó inocuo al alimentar a adultos y larvas de C. montrouzieri con presa previamente tratada. Se determinaron los efectos letales y subletales de los tres insecticidas sobre Aphytis melinus DeBach (Hymenoptera: Aphelinidae), principal parasitoide de Aonidiella aurantii (Maskell) (Hemipteta: Diaspididae) en cítricos. En adultos, clorpirifos y spinosad resultaron tóxicos mientras que spirotetramat resultó moderadamente tóxico. Sobre inmaduros de A. melinus, clorpirifos resultó moderadamente tóxico, spirotetramat ligeramente tóxico y spinosad inocuo. Así, spirotetramat se podría utilizar contra P. kellyanus en parcelas con niveles poblacionales bajos cuando deba tratarse también cont / [CAT] Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) és, actualment, una plaga més dels cítrics valencians. Les nimfes es refugien i s'alimenten de la superfície dels fruits recentment quallats que produeix unes escarificacions circulars al voltant del peduncle del fruit i devaluen el seu valor al mercat. Hui en dia, el control químic és pràcticament l'única alternativa contra aquest trips. Per poder millorar la gestió integrada de P. kellyanus és necessari un major coneixement sobre la seua biologia i ecologia en camp. Per a això, s'ha avaluat la dinàmica poblacional de les nimfes de P. kellyanus durant el període on els fruits recentment quallats són més sensibles als danys produïts per les nimfes. A més, s'ha estudiat la distribució de la plaga dins dels arbres i el seu moviment al llarg del dia, factors necessaris per a estimar la població de trips i per afinar les aplicacions de productes fitosanitaris. Tant la dinàmica com els danys van variar segons parcel¿les i anys, després de la caiguda de pètals es van observar una o dues generacions de nimfes que van produir danys als fruits. Aquest resultat subratlla la necessitat de realitzar mostrejos setmanals des de la caiguda de pètals fins i tot després del tractament contra la primera generació. Segons les dades obtingudes, quan es dóna una segona generació de P. kellyanus, aquesta és més perjudicial per als fruits. Les nimfes van mostrar un clara preferència pels fruits situats a la part alta de la copa, coincidint amb el major nombre de fruits danyats en aquesta zona. No obstant això, la distribució de les nimfes va ser uniforme en les quatre orientacions de l'arbre i la seva abundància tampoc va variar al llarg del dia. Per tant, son factors que no semblen ser claus a l'hora de desenvolupar un pla de mostreig o realitzar aplicacions fitosanitàries.
El següent objectiu va ser determinar l'eficàcia de tres insecticides (clorpirifos, spinosad i spirotetramat), amb acció diferent, en el control de les nimfes de P. kellyanus. Clorpirifos i spinosad van reduir significativament el percentatge de fruits danyats quan es va donar una sola generació de nimfes, però no varen evitar l'atac d'una segona generació de nimfes. Spirotetramat no va presentar un efecte de xoc contra aquesta plaga i tampoc va evitar l'atac d'una segona generació. En aquests treballs de camp, se va analitzar els efectes secundaris d'aquests tres insecticides sobre els enemics naturals presents en el moment dels tractaments. Spinosad i spirotetramat van afectar negativament les poblacions fitoseids en camp. Com varen ser baixes les poblacions de la resta d'enemics naturals es va estudiar els efectes secundaris sobre coccinélids i parasitoids en condicions de laboratori.
Es varen determinar els efectes letals i subletals de spirotetramat en adults i larves de Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) per aplicació directa dels productes i per ingestió de presa, Planococcus citri Risso (Hemiptera: Pseudococcidae), prèviament tractada pels productes. Spirotetramat va resultar innocu a la aplicació directa sobre larves o adults de C. montrouzieri, no va afectar la supervivència, longevitat fecunditat, fertilitat i supervivència de la descendència. I el mateix quan adults i larves de van ser alimentats amb presa prèviament tractada.
Finalment, es van determinar els efectes letals i subletals dels tres insecticides sobre Aphytis melinus DeBach (Hymenoptera: Aphelinidae), principal parasitoid de Aonidiella aurantii (Maskell) (Hemipteta: Diaspididae) en cítrics. En adults, clorpirifos i spinosad van resultar tòxics, spirotetramat va resultar moderadament tòxic. Sobre immadurs de A melinus, clorpirifos va resultar moderadament tòxic, spirotetramat lleugerament tòxic i spinosad innocu. Així, spirotetramat es podria utilitzar contra P. kellyanus en parcel¿les amb nivells poblacionals baixos aprofitant el tractament contra A. aurantii al p / Planes Insa, L. (2016). BASES PARA LA GESTIÓN INTEGRADA DE PEZOTHRIPS KELLYANUS (BAGNALL) (THYSANOPTERA: THRIPIDAE) EN CÍTRICOS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63676 / TESIS
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Diversity and Habitat Selection of Papilionidae in a Protected Forest Reserve in Assam, Northeast India / Boidiversität und Lebensraumwahl der Schmetterlingsfamilie Papilionidae in Assam, Nordost IndienBarua, Kamini Kusum 23 January 2008 (has links)
No description available.
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