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Fauzia Anjum Chattha Munawar Ali Munawar Saeed Ahmad Nagra Mohammad Ashraf Misbahul Ain Khan Samina Kosur 《Journal of Plant Growth Regulation》2013,32(2):291-297
Indazoles are valuable because of their biological activities. A series of 3-aryl-1H-indazoles have been synthesized by condensing bisulfite adduct of aromatic aldehydes with phenyl hydrazine in good yield. Different concentrations of indazoles were employed to check their effects on seed germination and early growth. The arylindazoles were proved to be growth inhibitors of root and shoot lengths of wheat and sorghum, especially at a high concentration (100 ppm). At lower concentrations growth inhibition was found to be less prominent. Seed germination and early growth of plantlets also depended on the nature of substitution on the aryl group. 相似文献
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Mid-Holocene coral community data as baselines for understanding contemporary reef ecological states
Ronan C. Roche Chris T. Perry Kenneth G. Johnson Kerry Sultana Scott G. Smithers Angus A. Thompson 《Palaeogeography, Palaeoclimatology, Palaeoecology》2011,299(1-2):159-167
Land-use changes and associated deteriorations in water quality are cited as major drivers of marine ecosystem change, and can modify community abundance and diversity on coral reefs. This study uses palaeoecological data derived from a mid-Holocene age coral reef in the Wet Tropics region of Australia's Great Barrier Reef to develop a record of coral community composition and diversity, from a period that significantly pre-dates European settlement in the region. Major changes in catchment sediment and nutrient yields since European settlement have been documented, and thus the data presented provides a baseline against which to compare contemporary ecological datasets. Natural variations in coral assemblage composition, as preserved in core records, clearly occurred in this mid-Holocene reef and were associated with the reef shallowing to sea level as it accreted vertically. Comparisons between modern and mid-Holocene coral community data from equivalent water depths did not reveal marked shifts in coral community composition and diversity, suggesting the long-term persistence of a resilient coral assemblage over these time periods. 相似文献
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Sanghee Kim Mi‐Hyun Park Jae‐Ho Jung Dong‐Ha Ahn Tahera Sultana Sejoo Kim Joong‐Ki Park Han‐Gu Choi Gi‐Sik Min 《Zoologica scripta》2012,41(3):281-292
Kim, S., Park, M.‐H., Jung, J.‐H., Ahn, D.‐H., Sultana, T., Kim, S., Park, J.‐K., Choi, H.‐G. & Min, G.‐S. (2012). The mitochondrial genomes of Cambaroides similis and Procambarus clarkii (Decapoda: Astacidea: Cambaridae): the phylogenetic implications for Reptantia. —Zoologica Scripta, 41, 281–292. We determined the complete mitochondrial (mt) genome sequences of two northern hemisphere freshwater crayfish species, Cambaroides similis and Procambarus clarkii (Decapoda: Astacidea: Cambaridae). These species have an identical gene order with typical metazoan mt genome compositions. However, their gene arrangement was very distinctive compared with the pan‐crustacean ground pattern because of the presence of a long inverted block, which included 19 coding genes and a control region (CR). Because the CR was inverted, their nucleotide frequencies showed a reversed strand‐specific bias compared with the other decapods. Based on a comparative analysis of mt genome arrangements between southern and northern hemisphere crayfish and their putative close marine relative (Homarus americanus, a true clawed lobster), we postulated that the ancestor of freshwater crayfish had a typical pan‐crustacean mtDNA gene order, similar to its marine relatives. Based on this assumption, we traced the most parsimonious gene rearrangement scenario of the northern hemisphere crayfish. In a phylogenetic study on the infraordinal relationships in reptan decapods, the lineage Lineata [Thalassinidea (Brachyura, Anomura)] was well supported, while the infraorder positions of Achelata and Astacidea remained unidentified. 相似文献
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