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121.
Aichatou Assoumane Carole Blay Abdel-Kader Alio Sanda Cédric Mariac Jean-Louis Pham Gilles Bezançon Yves Vigouroux 《Genetic Resources and Crop Evolution》2018,65(4):1187-1194
Wild crop relatives are unique genetic resources for crop adaptation. Increasing pressure from agriculture threatens these populations both by reducing their habitats and by creating opportunities for wild-cultivated hybridization. In this study, we assessed the diversity of 38 wild pearl millet populations covering the whole known distribution of the species in Africa, which extends from Senegal to Sudan. Using genetic analyses of 10 cultivated varieties as control, we demonstrate the high diversity harbored by these wild populations. Diversity patterns suggest a diversity hot-spot in the southern part of the wild population’s range. However, this high wild genetic diversity could partly be explained by introgression from cultivated varieties. Such introgression is widespread in the Sahel. We validate the impact of cultivated introgression on the diversity of the wild population using a genetic introgression model. The introgression distorts the real assessment of the diversity of the wild population, and the burden of this gene flow compromises the long term survival of the wild populations’ original genome. Our study also questions the long term survival of the crop’s wild relatives. 相似文献
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123.
Chuong V. Huynh Nguyen Phuong T. Pham Tung G. Nguyen Hai T. Nguyen Mai T. H. Tran Phuong T. 《Eurasian Soil Science》2022,55(8):1041-1051
Eurasian Soil Science - We investigate the key predictors that influence the soil organic matter (SOM) content in higher altitude plantations. This is to study the potential of carbon sequestration... 相似文献
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125.
Pham Van Thanh Jaime A. Teixeira Da Silva Ham Le Huy 《The Journal of Horticultural Science and Biotechnology》2013,88(5):473-478
SummaryThis is the first study to address the effects of permanent magnetic fields (MFs) on the in vitro growth of Phalaenopsis plantlets. Uniform Phalaenopsis Gallant Beau ‘George Vazquez’ plantlets, each with two leaves and two roots, and each approx. 2 cm in height, were excised from a mass of protocorm-like bodies (PLBs) after 3 months of sub-culture. The plantlets (n = 21) were cultured in a film culture system (‘Miracle Pack’®) under MFs of different intensity: 0.10, 0.15, or 0.20 Tesla (T). Each culture vessel at each MF intensity was cultured on the North (N) or South (S) poles of specialised magnets. The 0.15 T MF was also applied for different lengths of time (1, 2, or 3 months) at both the N and S poles. Control plantlets were simply exposed to the naturally-occurring geo-MF, and not to any induced MF. All MFs tested had a positive influence on shoot and root development, but did not influence chlorophyll contents. Among all the intensities and polarities of MF tested, 0.10 T – S had the greatest positive influence on specific growth parameters of Phalaenopsis plantlets such as maximum leaf length, root length, fresh weight and dry weight of shoots and roots, and leaf width. Constant exposure to a MF of 0.15 T for 3 months, at either the N or S poles, significantly enhanced the development of plantlets.The results obtained in this study indicate that MFs can have a positive effect on the efficiency and quality of clonal Phalaenopsis plantlets during commercial production. The MFs from commercially-produced permanent magnets enhanced Phalaenopsis plantlet growth significantly and can be used as a novel means to study the effect of MFs on plant growth and development, or to control morphogenesis in limited spaces such as space stations. 相似文献
126.
Pham Thanh-Thao Proulx Suzie Brochu Charles Moore Serge 《Water, air, and soil pollution》1999,111(1-4):251-270
Samples of treated wastewater drawn from the effluent of the Montreal Urban Community (MUC), Canada, and surface water samples from the St. Lawrence River were collected in 1993 and 1994 and analysed for PCBs and PAHs. The average concentrations of Σ13 PCBs and Σ14 PAHs in the effluent were 1.34 ± 0.71 ng L-1 and 326 ± 229 ng L-1, respectively. PCB concentrations in the effluent did not show any clear seasonal pattern in the effluent but PAH concentrations increased during the winter period. In the effluent plume, both PCB and PAH concentrations increased significantly between the upstream control site and the effluent outfall, and subsequently decreased. The profiles of PCB congeners were similar within the effluent plume and also among water masses of the St. Lawrence River. PAH profiles were also similar within the effluent plume, but were different across the two water masses of the St. Lawrence River. Based on the composition of PCB congeners, atmospheric inputs appear to represent the major source of PCBs in the St. Lawrence River. The sources of PAHs in the MUC effluent and in the St. Lawrence River water would appear to be, respectively, petroleum products and combustion-derived products. 相似文献
127.
Luong Bui Bich Hanh Phung Thi My Rinh Pham Dinh Trang Pham Minh Thang Do Trong Stephen Harper 《Communications in Soil Science and Plant Analysis》2019,50(1):102-107
Inductively coupled plasma-mass spectroscopic (ICP-MS) analysis of leaves from 22 cabbage crops in the Sa P? and B?c Hà districts of Láo Cai Province, North-Western Vi?t Nam, revealed unexpectedly high concentrations of chromium (Cr) and nickel (Ni). The concentrations were strongly linearly related (r2 = 0.94), indicating sample contamination during grinding through a stainless-steel hammer mill. We tested this hypothesis in two ways. First, brown rice ground through the same mill was contaminated not only by Cr and Ni, but also cobalt (Co), iron (Fe) and molybdenum (Mo). Second, scanning electron microscopy/energy dispersive analysis of x-rays (SEM/EDS) of the ground samples revealed small fragments with co-located Fe, Cr and Ni, consistent with stainless steel wear fragments. Other grinders may perform differently and we suggest that quality assurance protocols for trace metal analysis of plants should include testing for grinder wear metals. Lastly, brown rice appears to be convenient for investigating contamination of plant tissues during grinding. 相似文献
128.
Phytochemical investigation of Laureliopsis philippiana resulted in isolation of a new bisbenzylisoquinoline alkaloid (1) named laureliopsine A. The structure was established by spectroscopic methods, including 2D homo- and heteronuclear NMR experiments. This finding of a bisbenzylisoquinoline alkaloid in Laureliopsis supports its close relationship to Atherosperma and its taxonomic segregation from Laurelia. 相似文献
129.
Let MB Jacobsen C Pham KA Meyer AS 《Journal of agricultural and food chemistry》2005,53(13):5429-5437
The ability of rapeseed oil and/or different antioxidants (alpha- and gamma-tocopherol mixture, ascorbyl palmitate, and EDTA) to protect fish-oil-enriched milk emulsions against oxidation was investigated. Tocopherol isomers in concentrations similar to those found in natural rapeseed oil were added to rapeseed oil stripped of natural tocopherols. The rapeseed oil with added tocopherols significantly inhibited oxidation in the fish-oil-enriched milk emulsions. In contrast, the emulsions with only fish oil and added alpha- and gamma-tocopherol were less stable than the emulsions with fish oil alone. When added individually, the gamma-tocopherol seemed to inhibit oxidation more efficiently than alpha-tocopherol. Ascorbyl palmitate (AP) almost completely retarded oxidation in the fish-oil-enriched milk emulsions, as determined by PV, volatile oxidation products, and sensory evaluation. AP also prevented the otherwise prooxidant effect of tocopherols added to fish oil before emulsification. No interactions between AP, tocopherols, and EDTA were observed, and EDTA added alone to fish oil did not show antioxidant properties in the milk emulsions. Overall, the results showed that addition of AP or rapeseed oil containing natural tocopherols to fish oil was equally efficient in inhibiting oxidation in the fish-oil-enriched milk emulsions. 相似文献
130.
M. Wenneker K. T. K. Pham M. E. C. Lemmers F. A. de Boer P. J. van Leeuwen T. C. Hollinger F. G. van de Geijn B. P. H. J. Thomma 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(1):213-217
In a survey for postharvest diseases of apples and pears in the Netherlands, an unknown postharvest fruit rot was observed. The disease appeared to originate from infected lenticels. A fungus was consistently isolated from the decayed fruits. The fungal pathogen was isolated on potato dextrose agar, and at low temperatures development of a fast-growing whitish mycelium was observed. Growth of this fungus was observed between 1 and 20 °C with an optimum at 15 °C, while incubation of mycelium at 25 °C resulted in no growth. The isolates did not produce asexual or sexual spores. The isolates were characterized and identified by morphology and molecular phylogenetic analysis. Genomic DNA was isolated and amplified using ITS1-ITS4, EF1 and RPB2 primers, and BLAST searches in GenBank placed the fungus taxonomically in the genus Fibulorhizoctonia, with the highest matches to F. psychrophila. Pathogenicity of representative isolates from apple and pear fruit was confirmed under laboratory conditions. To the best of our knowledge this is the first report of F. psychrophila causing lenticel spot on apple and pear, and also the cause of a whitish mould on storage bins. 相似文献