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41.
ROBIN SHARP 《Ibis》1995,137(S1):S219-S223
The Biodiversity Convention requires parties to prepare national plans with strategies for the conservation of biodiversity. The U.K. produced its Action Plan in January 1994, one of the first countries to do so. The document of nearly 200 pages sets out the rationale for conserving biodiversity and the U.K. scientific tradition which underpins our understanding of biodiversity and describes in very summary form the key characteristics of U.K. biodiversity and the resources we devote to sustaining it, both in situ and ex situ, as well as our contribution to assisting conservation outside the U.K. It goes on to consider the role of education and public information and the need to improve the coordination and accessibility of scientific data and monitoring. Finally, it sets out a range of targets and commitments including a proposal to set up machinery, involving non-governmental interests, to agree on specific targets for key species and habitats in 1995. The main emphasis of the Plan and the work ahead is to create a collaborative framework for the large but fragmented efforts by the public voluntary sectors to reverse recent losses of biodiversity. In many ways bird conservation and population monitoring provide a benchmark for other species work. Bird conservation will benefit from the increased integration of effort and scientific analysis which looks at the interaction of species, habitats and wider land use issues and the effect of sectoral policies such as agriculture, energy and transport. 相似文献
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Background
Affymetrix High Density Oligonuclotide Arrays (HDONA) simultaneously measure expression of thousands of genes using millions of probes. We use correlations between measurements for the same gene across 6685 human tissue samples from NCBI's GEO database to indicated the quality of individual HG-U133A probes. Low correlation indicates a poor probe. 相似文献48.
Root Growth and Water Uptake by Maize Plants in Drying Soil 总被引:16,自引:0,他引:16
Sharp, R. E and Da vies, W. J. 1985. Root growth and water uptakeby maize plants in drying soil. J. exp. Bot. 36: 14411456. The influence of soil drying on maize (Zea mays L.) root distributionand use of soil water was examined using plants growing in thegreenhouse in soil columns. The roots of plants which were wateredwell throughout the 18 d experimental period penetrated thesoil profile to a depth of 60 cm while the greatest percentageof total root length was between 2040 cm. High soil waterdepletion rates corresponded with these high root densities.Withholding water greatly restricted root proliferation in theupper part of the profile, but resulted in deeper penetrationand higher soil water depletion rates at depth, compared withthe well watered columns. The deep roots of the unwatered plantsexhibited very high soil water depletion rates per unit rootlength. Key words: Maize, roots, water deficit, soil water depletion 相似文献
49.
Growth and Water Relations of Wilty Mutants of Tomato (Lycopersicon esculentum Mill.) 总被引:2,自引:0,他引:2
In contrast to some previous reports on the growth of the ABA-deficientwilty mutants of tomato, growth was at least as rapid in themutants as in the wild type, as long as an adequate plant waterstatus was maintained by growing the plants under mist. Moreover,shoot extension was greater and the rate of leaf productionmore rapid in the mutants. Stomatal changes in response to environmentand to time in the light-dark cycle were generally similar inboth wilty mutants and the wild type, though the wild-type weregenerally more closed. Grafting experiments confirmed that thegenotype of the shoot was dominant in determining stomatal aperture,though wild-type rootstocks could cause a slight reduction inthe stomatal conductance of mutant leaves. The effect on plantwater relations of draughting only part of the root system wasinvestigated in a split-root experiment. Withholdingwater from only part of the root system was found to lower significantlythe mean leaf water potential, even though the potential evaporationrate was kept very small. Key words: Abscisic acid, stomata, tomato 相似文献
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The usefulness of exogenous nicotine as a factor in the induction of morphogenesis in a tobacco tissue culture medium has been demonstrated. Nicotiana rustica callus cell cultures were grown on a modified Murashige and Skoog medium with 2 mg/l indoleacetic acid (IAA) and 0.2 mg/l kinetin (MMS). Root morphogenesis was induced in roller tube callus cell cultures and solid callus cell cultures grown on MMS without kinetin supplemented with 10–100 mg/l nicotine. Optimal nicotine concentration for root induction was 50 mg/l. Other tests using varying combinations of IAA, kinetin and nicotine produced no obvious morphogenesis, although some changes in the amount of callus growth and endogenous protein concentration did correlate with nicotine concentration relative to the presence of IAA and/or kinetin. In liquid MMS medium, 14C-nicotine was primarily incorporated into the protein fraction of cultured cells while primarily incorporated into the cell wall and/or cell membrane fraction of cells cultured on MMS without kinetin in the medium. In MMS without IAA and MMS without both IAA and kinetin, there was incorporation, but to a lesser extent in both the protein and the cell wall and/or cell membrane fractions. 相似文献