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991.
First finding of a quarantine pest,Atherigona (Acritochaeta) orientalis Schiner (Diptera: Muscidae), in Korea 下载免费PDF全文
The invasive quarantine pest fly, Atherigona (Acritochaeta) orientalis Schiner, is observed for the first time in tomato greenhouses in Gyeongsangbuk‐do, Korea. The genus Atherigona Rondani is also newly added to Korean fauna. Allium tuberosum is listed as a new host crop for this species. Some morphological characteristics for accurate identification and host lists are given to provide plant quarantine information for pest management. 相似文献
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994.
Absence of Mate Choice and Postcopulatory Benefits in a Species with Extreme Sexual Size Dimorphism 下载免费PDF全文
Marie‐Claire Chelini Eileen A. Hebets 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(2):95-104
Most hypotheses related to the evolution of female‐biased extreme sexual size dimorphism (SSD) attribute the differences in the size of each sex to selection for reproduction, either through selection for increased female fecundity or selection for male increased mobility and faster development. Very few studies, however, have tested for direct fitness benefits associated with the latter – small male size. Mecaphesa celer is a crab spider with extreme SSD, whose males are less than half the size of females and often weigh 10 times less. Here, we test the hypotheses that larger size in females and smaller size in males are sexually selected through differential pre‐ and postcopulatory reproductive benefits. To do so, we tested the following predictions: matings between small males and large females are more likely to occur due to mate choice; females mated to small males are less likely to accept second copulation attempts; and matings between small males and large females will result in larger clutches of longer‐lived offspring. Following staged mating trials in the laboratory, we found no support for any of our predictions, suggesting that SSD in M. celer may not be driven by pre‐ or post‐reproductive fitness benefits to small males. 相似文献
995.
We used a mitochondrial and nuclear DNA phylogeny to evaluate the relationships among all noddies (Anous and Procelsterna, Laridae) and to clarify their classification. The Lesser Noddy Anous tenuirostris and Black Noddy Anous minutus form a pair of closely related sister‐species, as do the Blue Noddy Procelsterna albivitta and Grey Noddy Procelsterna cerulea. Blue and Grey Noddies are embedded within the dark noddies and are the sister‐clade to the Lesser and Black Noddies, indicating that the genus Anous in its current definition is not monophyletic. Thus, we propose to merge all noddies into the genus Anous Stephens 1826 , and to consider Procelsterna Lafresnaye 1842 as a junior synonym. 相似文献
996.
Integration of habitat models to predict fish distributions in several watersheds of Northern Spain 下载免费PDF全文
A. M. González‐Ferreras J. Barquín F. J. Peñas 《Zeitschrift fur angewandte Ichthyologie》2016,32(1):204-216
Species distribution models and consensus models allow knowing the distribution of species in large areas where there is no field data and identifying the most important drivers for those distributions. In this study, seven individual models were used to obtain a consensus model to determine the potential distribution for six freshwater fish species in several watersheds of Northern Spain. Moreover, three different methods of model evaluation were used for performance comparison. Fish data were obtained from databases provided by different organisms related to aquatic systems containing information on 759 field sites sampled between October 2002 and June 2011 using electrofishing techniques. Dependent variables were obtained after filtering field sites according to a human pressure gradient analysis, while independent variables were derived from a Synthetic River Network for the study area. The ‘best’ individual models were obtained using Random Forest, Generalized Boosted Models and Generalized Additive Models, but with differing results among species and evaluation methods. The different consensus models revealed a high degree of adjustment between modelled and observed data. The most important factors related to fish distributions were the width of the valley floor, mean annual flow, average catchment elevation, distance to the sea, and total catchment area. The importance and critical limits of presence‐absence for these key variables differed among species. Use of these models could assist in the prioritization and selection of specific catchment and river reach actions for fish population management, restoration and/or conservation. 相似文献
997.
998.
Strong sexual selection in males against a mutation load that reduces offspring production in seed beetles 下载免费PDF全文
Theory predicts that sexual reproduction can increase population viability relative to asexual reproduction by allowing sexual selection in males to remove deleterious mutations from the population without large demographic costs. This requires that selection acts more strongly in males than females and that mutations affecting male reproductive success have pleiotropic effects on population productivity, but empirical support for these assumptions is mixed. We used the seed beetle Callosobruchus maculatus to implement a three‐generation breeding design where we induced mutations via ionizing radiation (IR) in the F0 generation and measured mutational effects (relative to nonirradiated controls) on an estimate of population productivity in the F1 and effects on sex‐specific competitive lifetime reproductive success (LRS) in the F2. Regardless of whether mutations were induced via F0 males or females, they had strong negative effects on male LRS, but a nonsignificant influence on female LRS, suggesting that selection is more efficient in removing deleterious alleles in males. Moreover, mutations had seemingly shared effects on population productivity and competitive LRS in both sexes. Thus, our results lend support to the hypothesis that strong sexual selection on males can act to remove the mutation load on population viability, thereby offering a benefit to sexual reproduction. 相似文献
999.
Hyeong-Kyu Jeon Hansol Park Dongmin Lee Seongjun Choe Kyu-Heon Kim Woon-Mok Sohn Keeseon S. Eom 《The Korean journal of parasitology》2016,54(2):181-185
Human sparganosis is a zoonotic disease caused by infection with larval forms (procercoid/plerocercoid) of Spirometra spp. The purpose of this study was to identify Spirometra spp. of infected snakes using a multiplex PCR assay and phylogenetic analysis of mitochondrial DNA sequence data from the spargana of terrestrial snakes obtained from Korea and China. A total of 283 snakes were obtained that included 4 species of Colubridae comprising Rhabdophis tigrinus tigrinus (n=150), Dinodon rufozonatum rufozonatum (n=64), Elaphe davidi (n=2), and Elaphe schrenkii (n=7), and 1 species of Viperidae, Agkistrodon saxatilis (n=60). The snakes were collected from the provinces of Chungbuk, Chungnam, and Gyeongbuk in Korea (n=161), and from China (n=122). The overall infection rate with spargana was 83% (235/283). The highest was recorded for D. rufozonatum rufozonatum (100%), followed by A. saxatilis (85%) and R. tigrinus tigrinus (80%), with a negative result for E. davidi (0%) and E. schrenkii (0%). The sequence identities between the spargana from snakes (n=50) and Spirometra erinaceieuropaei () or S. decipiens ( KJ599680) control specimens were 90.8% and 99.2%, respectively. Pairwise genetic distances between spargana (n=50) and S. decipiens ranged from 0.0080 to 0.0107, while those between spargana and S. erinaceieuropaei ranged from 0.1070 to 0.1096. In this study, all of the 904 spargana analyzed were identified as S. decipiens either by a multiplex PCR assay (n=854) or mitochondrial cox1 sequence analysis (n=50). KJ599679相似文献
1000.
Differences in defence responses of Pinus contorta and Pinus banksiana to the mountain pine beetle fungal associate Grosmannia clavigera are affected by water deficit 下载免费PDF全文
Adriana Arango‐Velez Walid El Kayal Charles C. J. Copeland L. Irina Zaharia Inka Lusebrink Janice E. K. Cooke 《Plant, cell & environment》2016,39(4):726-744
We tested the hypotheses that responses to the mountain pine beetle fungal associate Grosmannia clavigera will differ between the evolutionarily co‐evolved host lodgepole pine (Pinus contorta var. latifolia) and the naïve host jack pine (Pinus banksiana) and that these responses will be influenced by water availability. G. clavigera inoculation resulted in more rapid stem lesion development in lodgepole than in jack pine; water deficit delayed lesion development in both species. Decreased hydraulic conductivity was observed in inoculated lodgepole pine seedlings, likely because of tracheid occlusion by fungal hyphae and/or metabolite accumulation. Drought but not inoculation significantly impacted bark abscisic acid levels. Jasmonic and salicylic acid were implicated in local and systemic responses of both species to G. clavigera, with salicylic acid appearing to play a greater role in jack pine response to G. clavigera than lodgepole pine. Water deficit increased constitutive levels and/or attenuated induced responses to G. clavigera for several monoterpenes in lodgepole but not jack pine. Instead, inoculation of well‐watered but not water deficit jack pine resulted in a greater number of xylem resin ducts. These findings reveal mechanisms underlying differences in G. clavigera‐induced responses between lodgepole and jack pine hosts, and how water availability modulates these responses. 相似文献