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Environmental pressure, land utilization, and economic feasibility have resulted in the development of recirculating aquaculture systems (RAS). For many RAS, sludge is collected and washed from the system to waste stabilization ponds (WSPs). However, disposal of brackishwater aquaculture sludge into WSP is often prohibited because the high salinity can interfere with treatment. Moreover, there are problems associated with WSPs because of elevated salt content, such as the common practice of reusing treated water and land application of stabilized sludge. We tested and compared the treatment of brackishwater aquaculture sludge in an upflow anaerobic sludge blanket (UASB) reactor as an alternative to a WSP. In UASB, wastewater flows upward through a blanket of granular sludge and is treated by anaerobic micro‐organisms. Reduction in organic matter and 5‐d biochemical oxygen demand by 97 and 91%, respectively, was achieved in a UASB as compared to corresponding reductions of 22 and 41% in a WSP. During the UASB digestion process, methane is produced and recovered. Overall, a reduction in potential environmentally harmful factors such as salinization, land requirements, greenhouse gas emissions, as well as transportation costs are achieved, making the UASB reactor an attractive possible alternative for saline aquaculture sludge management.  相似文献   
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ABSTRACT Mixed infections of cucurbits by Cucumber mosaic virus (CMV) and potyviruses exhibit a synergistic interaction. Zucchini squash and melon plants coinfected by the potyvirus Zucchini yellow mosaic virus (ZYMV) and either Fny-CMV (subgroup IA) or LS-CMV (subgroup II) displayed strong synergistic pathological responses, eventually progressing to vascular wilt and plant death. Accumulation of Fny- or LS-CMV RNAs in a mixed infection with ZYMV in zucchini squash was slightly higher than infection with CMV strains alone. There was an increase in CMV (+) strand RNA levels, but no increase in CMV (-) RNA3 levels during mixed infection with ZYMV. Moreover, only the level of capsid protein from LS-CMV increased in mixed infection. ZYMV accumulated to similar levels in singly and mixed infected zucchini squash and melon plants. Coinfection of squash with the potyvirus Watermelon mosaic virus (WMV) and CMV strains increased both the Fny-CMV RNA levels and the LS-CMV RNA levels. However, CMV (-) strand RNA3 levels were increased little or not at all for CMV on coinfection with WMV. Infection of CMV strains (LS and Fny) containing satellite RNAs (WL47-sat RNA and B5*-sat RNA) reduced the accumulation of the helper virus RNA, except when B5*-sat RNA was mixed with LS- CMV. However, mixed infection containing ZYMV and the CMV strains with satellites reversed the suppression effect of satellite RNAs on helper virus accumulation and increased satellite RNA accumulation. The synergistic interaction between CMV and potyviruses in cucurbits exhibited different features from that documented in tobacco, indicating there are differences in the mechanisms of potyvirus synergistic phenomena.  相似文献   
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The methanol extract of Butea monosperma seeds, tested in vitro, showed significant anthelmintic activity.  相似文献   
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Eucalyptus spp. and their hybrids are frequently cloned and mass planted across farmland tracts and commercial plantations in northern India. It is a viable feeder species to the paper and pulp industries in this region. In 2018 and 2019, during field surveys conducted in northern India, a serious leaf blight disease was frequently observed in E. tereticornis plantations. Isolation from the blighted leaf samples consistently yielded fungal isolates having Calonectria‐like morphology. Morphological features coupled with sequence analysis of partial β‐tubulin (TUB2) and partial translation elongation factor‐alpha (TEF1) gene regions of two fungal isolates confirmed the species as Ca. cerciana. In detached leaf assays and glasshouse inoculation experiments, both isolates produced symptoms similar to those observed on the naturally infected leaves. Koch's postulates were fulfilled by re‐isolating Ca. cerciana from the inoculated leaves. This work is the first to confirm that Ca. cerciana is associated with a serious leaf blight disease of Eucalyptus in northern India and is an important addition to the taxonomy of Calonectria fungi in India.  相似文献   
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Segregation for salinity tolerance and ISSR markers based molecular polymorphism were investigated in a F3 plant population raised via single-seed descent method from a cross between salt-tolerant indica rice variety CSR10 and salt-susceptible premium traditional Basmati rice variety Taraori Basmati HBC19. A total of 130 F3plants were evaluated individually for salinity tolerance on 1–9 scale on the basis of seedling growth parameters; the average score ranged between 1.7 to 8.3. Frequency distribution curve obtained using the salinity tolerance data of F3 population and a chi-square analysis, showed a good fit to a normal distribution. Eleven plants each in the category of salt-tolerant and salt-susceptible were selected from the segregating F3 population for ISSR marker analysis. A total of 149 bands (4–11 bands per primer) ranging from 200 to 3530 bp were scored for the two rice varieties and the selected CSR10 × HBC19 segregating F3 plants using 26 ISSR primers. Of these, 89 were monomorphic and 60 were polymorphic. Of the 60 polymorphic bands,36 and 20 bands were specific to CSR10 andHBC19 respectively. The remaining four bands were amplified using UBC primers 810,848, 853 and 886 and present in only some of the CSR10 × HBC19 F3 plants. Notably, ISSR primers with dinucleotide repeat motif and 5'-anchored end amplified more number of bands (7.0 bands/primer) compared to3'-anchored dinucleotide primers (5.4bands/primer), but 3'-anchored dinucleotide primers revealed higher level of polymorphism (2.6 polymorphic bands/primer) compared to 5'-anchoreddinucleotide primers (1.43 polymorphic bands/ primer). While distribution of majority of the polymorphic bands were more or less in the expected ratios in salt-tolerant and/or salt-sensitive F3segregating plants, but some of the bands amplified using UBC ISSR primers 823, 825,826, 849, 853, 864, 866 and 884 showed highly skewed distribution. Such polymorphic bands stand greater chances of having a linkage with the genes/ QTLs for salinity tolerance and shall be the target for further studies. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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An in vitro propagation method for female plants of Momordica dioica (Roxb.) has been established. The nodal segments were harvested and the cut ends of the explants were sealed with wax and then surface sterilized and cultured. Bud breaking occurred on Murashige and Skoog’s (MS) agar-gelled medium + 2.0 mg L−1 6-Benzylaminopurine (BAP) + 0.1 mg L−1 Indole-3 acetic acid (IAA). The cultures were amplified by passages on MS medium supplemented with 1.0 mg L−1 BAP + 0.1 mg L−1 IAA. Further, shoot amplification (29.2 shoots per vessel) was achieved by subculturing of in vitro regenerated shoot clump on MS medium + 0.5 mg L−1 BAP + 0.1 mg L−1 IAA. The micropropagated shoots were subsequently transferred for root formation on half-strength MS medium + 2.0 mg L−1 Indole-3 butyric acid (IBA) with 89% success rate. The in vitro-regenerated shoots were also rooted ex vitro with 34% success. These plantlets were hardened in the greenhouse and transferred to the field. The established protocol is suitable for true to type cloning of mature female plant of M. dioica.  相似文献   
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Sediments from Lunkaransar dry lake in northwestern India reveal regional water table and lake level fluctuations over decades to centuries during the Holocene that are attributed to changes in the southwestern Indian monsoon rains. The lake levels were very shallow and fluctuated often in the early Holocene and then rose abruptly around 6300 carbon-14 years before the present (14C yr B.P.). The lake completely desiccated around 4800 (14)C yr B.P. The end of this 1500-year wet period coincided with a period of intense dune destabilization. The major Harrapan-Indus civilization began and flourished in this region 1000 years after desiccation of the lake during arid climate and was not synchronous with the lacustral phase.  相似文献   
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