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21.
Xing X Koch AM Jones AM Ragone D Murch S Hart MM 《Proceedings. Biological sciences / The Royal Society》2012,279(1731):1122-1130
During the process of plant domestication, below-ground communities are rarely considered. Some studies have attempted to understand the changes in root symbionts owing to domestication, but little is known about how it influences mycorrhizal response in domesticated crops. We hypothesized that selection for above-ground traits may also result in decreased mycorrhizal abundance in roots. Breadfruit (Artocarpus sp.) has a long domestication history, with a strong geographical movement of cultivars from west to east across the Melanesian and Polynesian islands. Our results clearly show a decrease in arbuscular mycorrhizas (AMs) along a domestication gradient from wild to recently derived cultivars. We showed that the vesicular and arbuscular colonization rate decreased significantly in more recently derived breadfruit cultivars. In addition, molecular analyses of breadfruit roots indicated that AM fungal species richness also responded along the domestication gradient. These results suggest that human-driven selection for plant cultivars can have unintended effects on below-ground mutualists, with potential impacts on the stress tolerance of crops and long-term food security. 相似文献
22.
Marie Helleberg Bamenla Q Goka Bartholomew D Akanmori George Obeng-Adjei Onike Rodriques Jorgen AL Kurtzhals 《Malaria journal》2005,4(1):1-7
In sub-Saharan Africa the highest overlap between malaria and HIV infections occurs in female adolescents. Yet control activities for these infections are directed to different target groups, using disparate channels. This reflects the lack of priority given to adolescents and the absence of an accepted framework for delivering health and health-related interventions to this high-risk group. In this paper it is argued that female adolescents require a continuum of care for malaria and HIV – prior to conception, during and after pregnancy and that this should be provided through adolescent services. The evidence for this conclusion is presented. A number of African countries are commencing to formulate and implement adolescent-friendly policies and services and disease control programs for malaria and HIV will need to locate their interventions within such programs to ensure widespread coverage of this important target group. Failure to prioritize adolescent health in this way will seriously limit the success of disease control programs for malaria and HIV prevention. 相似文献
23.
Susan J. Murch Chunzhao Liu Rosaura M. Romero Praveen K. Saxena 《Plant Cell, Tissue and Organ Culture》2004,78(1):63-68
Crescentia cujete L. is a widely distributed medicinal tree with a diverse range of phytochemicals used as medicinal compounds. Seedlings of
wild-harvested C. cujete were established in vitro and used as the starting material for the establishment of axenic cultures. Shoots were proliferated from nodal segments
and were maintained over a period of more than 2 years by sequential subculture on a medium containing 1.0 μmol l−1 kinetin. De novo regeneration was induced on petiole sections cultured onto a medium containing thidiazuron in combination with 2,4-dichlorophenoxyacetic
acid. Axenic cultures were also used to test the efficiency of three different cultivation systems for production of biomass
of C. cujete. Growth of plantlets in a temporary immersion bioreactor resulted in significant increases in biomass, leaf number, shoot
height and transplant efficiency. Plantlets grown in the bioreactors were acclimatized under greenhouse conditions. Together,
these experiments have established optimized parameters for propagation and growth of C. cujete plantlets in a sterile controlled environment for biochemical characterization and production of high-quality medicinal products. 相似文献
24.
Mithila Jugulam Murch Susan J. KrishnaRaj Sankaran Saxena Praveen K. 《Plant Cell, Tissue and Organ Culture》2001,67(1):1-9
Recent advances in the development of protocols for in vitro culture and genetic manipulation have provided new avenues for the development of novel varieties of Pelargonium and for use as model systems for investigating the factors controlling plant morphogenesis. Optimized techniques of meristem culture have supplemented the culture indexing methods in commercial greenhouse production resulting in availability of large-scale pathogen indexed planting material. Currently, technologies are available for the mass in vitro propagation of F1 hybrid Pelargonium through both organogenesis and somatic embryogenesis. The somatic embryogenesis model system has allowed researchers to identify critical factors controlling plant morphogenesis in vitro such as regulation of regeneration by growth regulators, choice of explant and characterization of induction and expression phases of morphogenesis in Pelargonium. Also, optimization of technologies for genetic transformation of Pelargonium opened up the possibilities for developing genotypes with novel characters, including resistance to some of the major diseases. Finally, the development of regeneration systems for Pelargonium spp. has facilitated conventional crop improvement programs, thereby providing a valuable resource to the horticultural industry. 相似文献
25.
Keith W.T.Goulding 《中国科学:生命科学英文版》2005,48(Z2)
The nitrogen (N) cycle is essentially 'leaky'. The losses of small amounts of nitrate to waters and of ammonia and nitrous oxide to the atmosphere are a part of the global biogeo-chemical N cycle. However, intensive agricultural production, industry and vehicle use have more than doubled the amount of 'reactive' N in the environment, resulting in eutrophication, ecosystem change and health concerns. Research has identified agricultural practices that cause large losses of N and, in some cases, developed solutions. This paper discusses the problems of maintaining productivity while reducing N losses, compares conventional with low input (integrated) and organic farming systems, and discusses wider options. It also looks at the need to integrate studies on N with other environmental impacts, set in the context of the whole farm system, to provide truly sustainable agricultural systems. 相似文献
26.
27.
Romano Ngui Noor Amira Abdul Halim Yamuna Rajoo Yvonne AL Lim Stephen Ambu Komalaveni Rajoo Tey Siew Chang Lu Chan Woon Rohela Mahmud 《The Korean journal of parasitology》2016,54(5):673-678
Epidemiological study on strongyloidiasis in humans is currently lacking in Malaysia. Thus, a cross-sectional study was carried out to determine the prevalence of Strongyloides stercoralis infection among the inhabitants of longhouse indigenous communities in Sarawak. A single stool and blood sample were collected from each participant and subjected to microscopy, serological and molecular techniques. Five species of intestinal parasites were identified by stool microscopy. None of the stool samples were positive for S. stercoralis. However, 11% of 236 serum samples were seropositive for strongyloidiasis. Further confirmation using molecular technique on stool samples of the seropositive individuals successfully amplified 5 samples, suggesting current active infections. The prevalence was significantly higher in adult males and tended to increase with age. S. stercoralis should no longer be neglected in any intestinal parasitic survey. Combination of more than 1 diagnostic technique is necessary to increase the likelihood of estimating the ‘true’ prevalence of S. stercoralis. 相似文献
28.
Halil brahim GÜLER Fulya AY AL Zehra CAN Yakup KARA Oktay YILDIZ Ali Osman BELDÜZ Sabriye ANAKI Sevgi KOLAYLI 《Turkish Journal of Biology》2021,45(4):530
Propolis is a multi-functional bee product rich in polyphenols. In this study, the inhibitory effect of Anatolian propolis against SARS-coronavirus-2 (SARS-CoV-2) was investigated in vitro and in silico. Raw and commercial propolis samples were used, and both samples were found to be rich in caffeic acid, p-coumaric acid, ferulic acid, t-cinnamic acid, hesperetin, chrysin, pinocembrin, and caffeic acid phenethyl ester (CAPE) at HPLC-UV analysis. Ethanolic propolis extracts (EPE) were used in the ELISA screening test against the spike S1 protein (SARS-CoV-2): ACE-2 interaction for in vitro study. The binding energy values of these polyphenols to the SARS-CoV-2 spike and ACE-2 protein were calculated separately with a molecular docking study using the AutoDock 4.2.6 program. In addition, the pharmacokinetics and drug-likeness properties of these eight polyphenols were calculated according to the SwissADME tool. The binding energy value of pinocembrin was highest in both receptors, followed by chrysin, CAPE, and hesperetin. Based on the in silico modeling and ADME (absorption, distribution, metabolism, and excretion) behaviors of the eight polyphenols, the compounds exhibited the potential ability to act effectively as novel drugs. The findings of both studies showed that propolis has a high inhibitory potential against the Covid-19 virus. However, further studies are now needed. 相似文献
29.
JUN GONG SHAN GAO DAVID McL. ROBERTS KHALED A.S. AL‐RASHEID WEIBO SONG 《The Journal of eukaryotic microbiology》2008,55(6):492-500
ABSTRACT. A new marine cyrtophorian ciliate Trichopodiella faurei n. sp., which belongs to the order Dysteriida, family Hartmannulidae, was investigated at the morphological and molecular levels. A combination of morphological features of the organism including the oval body shape, 2–3 contractile vacuoles, 22–28 nematodesmal rods in the cytopharyngeal basket, and 31–39 somatic kineties, distinguishes it from all other known congeners. In reconstructed small subunit (SSU) rRNA phylogenies, T. faurei groups with Isochona, a representative genus of the subclass Chonotrichia. The similarity of the infraciliature between hartmannulids and several chonotrichian examples also suggests that these taxa should be closely related. A new S943 intron belonging to group IC1 was identified in the SSU rRNA gene of this species. This intron is phylogenetically related to the S891 introns previously found in the suctorians Acineta sp. and Tokophrya lemnarum, and their internal guide sequences share four nucleotides, indicating that these introns were vertically inherited from a common phyllopharyngean ancestor and that reverse splicing might have been involved in the transposition. 相似文献
30.
ZHUO SHEN XIAOFENG LIN HONGAN LONG MIAO MIAO HONGBIN LIU KHALED A. S. AL‐RASHEID WEIBO SONG 《The Journal of eukaryotic microbiology》2008,55(6):510-514
ABSTRACT. The urosylid genus Pseudoamphisiella was established by Song (1996) with hitherto only two known congeners. In the present work, the morphology and infraciliature of a new member, Pseudoamphisiella quadrinucleata n. sp., a form with conspicuous alveolar layer and four macronuclear nodules isolated from the coastal waters both near Hong Kong and near Guangzhou, South China were investigated using living observation and protargol silver impregnation methods. Pseudoamphisiella quadrinucleata differs from other two known forms mainly by the number of macronuclear nodules: constantly four vs. two in Pseudoamphisiella alveolata and 24–57 in Pseudoamphisiella lacazei. To support this, the sequence of the small subunit rDNA of P. quadrinucleata n. sp. showed 14 and 74 nucleotides in comparison with that of the two known congeners, respectively, which hence firmly supports the validity of the new species. 相似文献