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181.
R. Bernaś A. Burzyński P. Dębowski A. Poćwierz‐Kotus R. Wenne 《Fisheries Management and Ecology》2014,21(5):398-409
Sea trout, Salmo trutta L., populations in the Slupia River basin have been affected by mass stocking with smolts and fry. This work is focused on a small‐scale differentiation in sea trout populations from one basin with a strong emphasis on the relationship between wild and hatchery origin fish. A total of 216 sea trout were genotyped at 10 microsatellite loci. Global FST obtained by amova was low at 0.0165. Pairwise FST were significant for all tests except wild and stocked adults. The highest pairwise difference was found between the hatchery sample and Kwacza (FST = 0.038). Analysis of the genetic structure revealed micro‐geographical differentiation with four subpopulations. The quality of the artificial spawning was found not to be adequate with a high risk of adverse effects to the whole population. All future stocking actions in the basin should consider the existing population structures. 相似文献
182.
Emília Ondrušková Zuzana Hečková-Jánošíková Slavomír Adamčík Miriam Kádasi Horáková Dominika Rakúsová-Sládková Katarína Adamčíková 《Scandinavian Journal of Forest Research》2018,33(7):650-656
Dothistroma needle blight (DNB) has been observed in Slovakia during the last two decades. Up until 2017, Dothistroma septosporum has only been detected and molecularly confirmed to cause DNB in Slovakia. Here, we report the detection of Dothistroma pini at six localities around Slovakia, representing different plantation types. Four pine species (Pinus sylvestris, P. nigra, P. mugo and P. jeffreyi) were confirmed as hosts of D. pini in Slovakia, of which only P. mugo has been previously reported as host in Slovakia. Three gene regions (ITS, EF1 –α, and ß-tubulin) of each of the 13 isolates were sequenced and assigned as D. pini. Based on ITS sequences, the studied isolates represent the haplotypes Dp_HAP.1, Dp_HAP.2. Both mating types were detected but at different localities. Our results suggest that in addition to D. septosporum, D. pini may contribute to DNB also in Slovakia. 相似文献
183.
184.
Morphological variation based on eight measured and four derived traits was studied to establish whether there was significant variation between populations and to identify the influence of the altitude on morphological differentiation among 44 natural stands of common oak (Quercus robur L.) in Bosnia and Herzegovina, ranging from 82 to 860 m. The results point to significant intra- and inter-population differences. Elevation-related variation is less pronounced and determined largely by microclimatic factors. The results could provide management strategies for species reintroduction in the study area. There are no differences in leaf morphology between the different branches of individual trees. However, there are important variations between the altitudinal groups and closely linked to environmental factors in all traits. An important recommendation is to use seeds from oak with attention to their altitudinal origin. 相似文献
185.
Cherry laurel (Prunus laurocerasus) is a native plant species in Serbian forests, but is also widely used for ornamental plantings. Following two extremely wet summers in 2014 and 2015, in spring and summer of 2016 and 2017, numerous cherry laurel plants with symptoms indicative for Phytophthora diseases, like wilting and chlorosis of leaves, dieback and bleeding bark necroses, were recorded in a park in Belgrade and in two ornamental nurseries in central Serbia. From necrotic bark samples and rhizosphere soil, self‐sterile Phytophthora isolates with woolly colonies were obtained. Due to the production of ellipsoid and elongated, non‐papillate sporangia in water and of ornamented oogonia with two‐celled antheridia in mating tests with tester strains of both Phytophthora × cambivora and P. cryptogea, these isolates were identified as P. ×cambivora which was confirmed by ITS sequence analysis. Pathogenicity of P. ×cambivora from cherry laurel (PCCL) was tested by inoculating one‐year‐old seedlings of cherry laurel under the bark. P. ×cambivora from European beech (PCB), and isolates of P. cactorum (CAC), P. cryptogea (CRY), P. plurivora (PLU) and P. ×serendipita (SER) were included as comparison. Three and a half months after inoculation, nine of the twelve plants in PCB, three in PCCL and CAC and two in PLU declined with longitudinal necroses and chlorosis, wilting and premature shedding of leaves. These results demonstrate the ability of P. ×cambivora to infect and cause decline of cherry laurel plants. The particularly high aggressiveness of the P. ×cambivora isolate from beech shows that this pathogen poses a serious risk to cherry laurel in the rare natural communities of cherry laurel and beech in Serbia. 相似文献
186.
Z. Jánošíková ‐ Hečková E. Ondrušková M. Barta R. Ostrovský M. Kádasi‐Horáková K. Pastirčáková M. Kobza K. Adamčíková 《Forest Pathology》2018,48(3)
The occurrence and distribution of Dothistroma needle blight (DNB) were studied in 2014–2017 around Slovakia. A total of 84 localities, both native and planted, were investigated, and the presence of DNB was confirmed in 73 of them. In all positive locations, symptoms typical of DNB were observed and the Dothistroma species was confirmed using species‐specific primers either from fungal cultures or directly from needles. Both Dothistroma species—D. septosporum and D. pini—were identified. Both species occurred together in 29 locations, only D. septosporum in 42 and only D. pini in two locations. The host range of D. septosporum included 10 pine species and two spruce species. The host range of D. pini comprised the same number of pine hosts but only one spruce species. Five pine hosts, P. aristata, P. coulteri, P. densiflora, P. jeffreyi, P. × schwerinii, and one spruce host P. abies are new hosts species of D. pini. P. densiflora and Picea pungens have earlier been reported to be susceptible for DNB. In this study, D. septosporum was found from both tree species. 相似文献
187.
Biological control of chestnut blight in Croatia: an interaction between host sweet chestnut,its pathogen Cryphonectria parasitica and the biocontrol agent Cryphonectria hypovirus 1
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188.
Monitoring of libido and semen quality parameters in melatonin‐treated French alpine bucks during the non‐breeding season
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H Valpotić V Berta S Milinković‐Tur M Samardžija J Grizelj B Špoljarić D Đuričić I Nazansky I Žura Žaja 《Reproduction in domestic animals》2017,52(6):953-961
The aim of this study was to investigate the effects of exogenous melatonin on libido and semen quality parameters in bucks during the non‐breeding season. Twelve bucks of the French alpine breed from 1.5 to 4 years of age were assigned into melatonin (MG) and control (CG) groups, with 6 bucks in each group. The experimental period was 3 months (March–May), divided into six periods of 15 days each. The bucks in the MG group received four melatonin implants at the end of March. Two semen samples were taken from the bucks by artificial vagina once per week and their libido estimated. Volume and spermatozoa concentration, their mass motility and motility, proportion of live and total abnormal and forms with abnormal head and tail were determined in the obtained ejaculate samples. The total number of spermatozoa and functional spermatozoa fraction in the ejaculate was also calculated. The MG bucks had significantly higher mass motility and motility of spermatozoa in the first half of April, and a higher proportion of live spermatozoa in the first and second half of April (p < .05). Differences in libido intensity were not significant. The results indicated that the application of melatonin significantly improved the qualitative parameters of semen in bucks, as seen in increased mass motility, motility of spermatozoa and proportion of live spermatozoa shortly following melatonin insertion. Therefore, the results of the current study are novel regarding the use of melatonin treatment during the non‐breeding season to improve the qualitative parameters of ejaculates in bucks. 相似文献
189.
Retracted: Gonad histology and serum 11‐KT profile during the annual reproductive cycle in sterlet sturgeon adult males,Acipenser ruthenus
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A Golpour C Broquard S Milla H Dadras AR Baloch T Saito M Pšenička 《Reproduction in domestic animals》2017,52(2):319-326
The aim of this study was to assess monthly testicular development in the cultured breeding stock of sterlet, Acipenser ruthenus, using histological and serum sex steroid changes. Testicular development in the adult male was examined monthly and showed four distinct phases including resting, pre‐spawning, spawning and post‐spawning. Also, seasonal changes of the testes were described according to its variations in gonadosomatic index (GSI) during different phases of testicular development. Using histology, we identified continuous spermatogenesis and asynchronous gonad development pattern in the testes of male sterlet, which shows that regulation of annual gonadal cycle is influenced by season. Results also showed variation in the GSI value and number of spermatogenic cells according to each season during annual cycle of gonad, as the highest value of GSI was recorded during spawning phase (spring; March‐May). Hormonal profiles of 11‐ketotestosterone (11‐KT) showed peak, which indicated a seasonal pattern of gonadal development. The 11‐KT concentration increased considerably during the spermatogenesis (pre‐spawning phase) and remained quite high throughout the pre‐spermiation period. In the final phase of testicular development (spawning phase), the 11‐KT markedly dropped. This study undertook an examination of complete reproductive development in cultured sterlet sturgeon to provide a valuable guide for the future sterlet studies, and allows comparison of reproductive development between sturgeon species. 相似文献
190.
Nina Zupančič 《Journal of Soils and Sediments》2017,17(4):1073-1083