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91.
A field study was conducted in the Western Ghats of peninsular India to test the following two hypotheses: (1) lower floristic diversity for the cardamom hill reserves (CHR —a traditional agroforestry system of the tropics) compared to undisturbed evergreen forests and (2) a truncated vegetation structure for shade trees in the cardamom areas. The experimental sites involved three CHRs and an evergreen forest site.The CHRs, regardless of their locations, were characterized by lower floristic diversity and density than the evergreen forest site. The undisturbed forest site at Ayyappancoil registered the highest floristic richness and diversity (Simpson's floristic diversity index, D=0.93), followed by the well-managed CHR site, suggesting that managerial interventions may have a strong bearing on the floristic diversity of CHRs. The current suite of species in the CHRs included both heliophilic as well as shade-tolerant components. However, dominant tree species, their density and relative abundance exhibited marked variations among the CHR sites, albeit about one-third of the species were common at all sites.Stand physiognomy was characterized by the dominance of a single layer of trees in the CHRs, while the wet evergreen forest exhibited a multilayered canopy structure. Some of the lower height classes were poorly represented in the cardamom areas, whereas the evergreen forests depicted an inverse J shaped height distribution pattern. Implicit in the truncated stand structure of the CHR is the poor regeneration status, due to systematic removal of the lower size classes.  相似文献   
92.
A new phorbol diester, 13-O-myristyl-20-O-acetyl-12-deoxyphorbol (1), has been isolated from the benzene extract of the heartwood of Aleurites moluccana. In addition, hentriacontane, 6,7-dimethoxycoumarin, 5,6,7-trimethoxycoumarin and beta-sitostenone are being reported for the first time from this species.  相似文献   
93.
Ether and methanol extracts of Ixora coccinea dry leaves were tested for their antimicrobial activity. Ether fraction was found to be more active than the methanol fraction.  相似文献   
94.
Kumar A  Ali M 《Fitoterapia》2000,71(2):101-104
A new steroidal alkaloid, named antidysentericine, has been isolated from the seeds of Holarrhena antidysenterica and characterized as 3 beta-dimethylaminocon-5-enin-18-one (1).  相似文献   
95.
96.
The combined efficacy of spinosad and chlorpyrifos-methyl was determined against four storage psocid pests belonging to genus Liposcelis. This research was undertaken because of the increasing importance of these psocids in stored grain and the problem of finding grain protectants to control resistant strains. Firstly, mortality and reproduction were determined for adults exposed to wheat freshly treated with either spinosad (0.5 and 1 mg kg(-1)) or chlorpyrifos-methyl (2.5, 5 and 10 mg kg(-1)) or combinations of spinosad and chlorpyrifos-methyl at 30 degrees C and 70% RH. There were significant effects of application rate of spinosad and chlorpyrifos-methyl, both individually and in combination, on adult mortality and progeny reduction of all four psocids. Liposcelis bostrychophila Badonnel and L. decolor (Pearman) responded similarly, with incomplete control of adults and progeny at both doses of spinosad but complete control in all chlorpyrifos-methyl and combined treatments. In L. entomophila (Enderlein) and L. paeta Pearman, however, complete control of adults and progeny was only achieved in the combined treatments, with the exception of spinosad 0.5 mg kg(-1) plus chlorpyrifos-methyl 2.5 mg kg(-1) against L. entomophila. Next, combinations of spinosad (0.5 and 1 mg kg(-1)) and chlorpyrifos-methyl (2.5, 5 and 10 mg kg(-1)) in bioassays after 0, 1.5 and 3 months storage of treated wheat were evaluated. The best treatment was 1 mg kg(-1) of spinosad plus 10 mg kg(-1) of chlorpyrifos-methyl, providing up to 3 months of protection against infestations of all four Liposcelis spp. on wheat.  相似文献   
97.
Agroforestry Systems - Tropical agroforestry practices play a crucial role in mitigating global climate change by absorbing CO2 from the atmosphere through photosynthesis and storing carbon in...  相似文献   
98.
99.
An outbreak of sheep associated malignant catarrhal fever in crossbred cattle in a village of Andhra Pradesh, southern India, affected thirteen adult cows and two calves from a population of forty animals. All the affected animals were died between December and January 2013–14. The clinical and gross postmortem findings were typical of MCF in Indian crossbred cattle. Migrating sheep flocks were suspected source of infection for the cattle. The diagnosis was confirmed by heminested PCR in all the affected cattle and the suspected sheep flock. The PCR provided evidence of ovine herpes virus type 2.  相似文献   
100.
Malignant catarrhal fever (MCF) is a fatal herpesvirus infection of domestic and wild ruminants, with a short and dramatic clinical course characterized primarily by high fever, severe depression, swollen lymph nodes, salivation, diarrhea, dermatitis, neurological disorders, and ocular lesions often leading to blindness. In the present study, fatal clinical cases of sheep associated malignant catarrhal fever (SA-MCF) were identified in cattle in the state of Karnataka. These cases were initially presented with symptoms of diarrhea, respiratory distress, conjunctivitis, and nasal discharges. Laboratory diagnosis confirmed the detection of ovine herpesvirus-2 (OvHV-2) genome in the peripheral blood samples of two ailing animals. The blood samples collected subsequently from sheep of the neighboring areas also showed presence of OvHV-2 genome indicating a nidus of infection in the region. The positive test results were further confirmed by nucleotide sequencing of the OIE approved portion of tegument gene as well as complete ORF8 region of the OvHV-2 genome. Phylogenetic analysis based on the sequence of the latter region indicated close genetic relationship with other OvHV-2 reported elsewhere in the world.  相似文献   
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