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591.
Dormancy release in potato tubers: A review 总被引:1,自引:0,他引:1
Warren K. Coleman 《American Journal of Potato Research》1987,64(2):57-68
Dormancy release in potato tubers is reviewed in the context of recent biochemical and physiological research with particular emphasis on describing ambiguities in the literature. A complex picture of dormancy release emerges with hypothetical multiple roles for most major plant growth regulator groups which occur within the tuber. Current literature continues to support the “inhibitor/promoter” hypothesis with the critical events associated with dormancy release involving a shift in the growth regulator ratio in favor of promoters and subsequent establishment of positive feedback between the bud and the mobilized food reserves. Dormancy release by external chemical agents possesses immediate practical applications such as dormancy breaking of seed tubers for export or local use, incorporation into seed multiplication programs and rapid post-harvest disease testing procedures. In addition, research using these chemical agents as experimental probes should prove useful in exploring the control mechanisms associated with dormancy release. 相似文献
592.
William E. Artz Cathryn C. Warren John W. Erdman Jr. Ricardo Villota 《Plant foods for human nutrition (Dordrecht, Netherlands)》1990,40(1):95-98
The feed efficiency and selected organ weights of rats fed diets containing 3 or 7% corn fiber, extruded corn fiber or silica were compared to rats fed a fiber-free diet. No significant differences were found in feed efficiency, spleen, lung or liver weights for any of the treatments relative to the fiber-free control diet. 相似文献
593.
Warren K. Coleman Gary Hawkins Jeff McInerney Marcus Goddard 《American Journal of Potato Research》1992,69(7):437-445
Tuber dormancy can be released immediately in many commercially important potato cultivars by brief treatment (1-2 days) with bromoethane (BE) vapor at room temperature. The development of a large scale technology for BE application and safe removal through a capturing technique is necessary for successful application of this dormancy release method. Ideally, BE treatment of seed tubers would occur in a closed environment that would capture BE vapor in an unaltered form and allow controlled release for treatment of subsequent tuber lots. Results of screening studies for adsorbents indicate that the medium capacity activated carbon adsorbent, YAO has: i) a high capacity for BE; ii) a low capacity for water; and, iii) adsorbs and de-adsorbs BE quickly and easily. A plausible design of a large scale, dormancy release facility is presented. The proposed facility should meet present goals of the seed potato industry in an environmentally responsible manner. 相似文献
594.
Hostetler JA Onorato DP Nichols JD Johnson WE Roelke ME O'Brien SJ Jansen D Oli MK 《Biological conservation》2010,143(11):2789-2796
Estimates of survival for the young of a species are critical for population models. These models can often be improved by determining the effects of management actions and population abundance on this demographic parameter. We used multiple sources of data collected during 1982-2008 and a live-recapture dead-recovery modeling framework to estimate and model survival of Florida panther (Puma concolor coryi) kittens (age 0-1 year). Overall, annual survival of Florida panther kittens was 0.323 ± 0.071 (SE), which was lower than estimates used in previous population models. In 1995, female pumas from Texas (P. c. stanleyana) were released into occupied panther range as part of an intentional introgression program to restore genetic variability. We found that kitten survival generally increased with degree of admixture: F1 admixed and backcrossed to Texas kittens survived better than canonical Florida panther and backcrossed to canonical kittens. Average heterozygosity positively influenced kitten and older panther survival, whereas index of panther abundance negatively influenced kitten survival. Our results provide strong evidence for the positive population-level impact of genetic introgression on Florida panthers. Our approach to integrate data from multiple sources was effective at improving robustness as well as precision of estimates of Florida panther kitten survival, and can be useful in estimating vital rates for other elusive species with sparse data. 相似文献
595.
Zolensky ME Zega TJ Yano H Wirick S Westphal AJ Weisberg MK Weber I Warren JL Velbel MA Tsuchiyama A Tsou P Toppani A Tomioka N Tomeoka K Teslich N Taheri M Susini J Stroud R Stephan T Stadermann FJ Snead CJ Simon SB Simionovici A See TH Robert F Rietmeijer FJ Rao W Perronnet MC Papanastassiou DA Okudaira K Ohsumi K Ohnishi I Nakamura-Messenger K Nakamura T Mostefaoui S Mikouchi T Meibom A Matrajt G Marcus MA Leroux H Lemelle L Le L Lanzirotti A Langenhorst F Krot AN Keller LP Kearsley AT 《Science (New York, N.Y.)》2006,314(5806):1735-1739
The bulk of the comet 81P/Wild 2 (hereafter Wild 2) samples returned to Earth by the Stardust spacecraft appear to be weakly constructed mixtures of nanometer-scale grains, with occasional much larger (over 1 micrometer) ferromagnesian silicates, Fe-Ni sulfides, Fe-Ni metal, and accessory phases. The very wide range of olivine and low-Ca pyroxene compositions in comet Wild 2 requires a wide range of formation conditions, probably reflecting very different formation locations in the protoplanetary disk. The restricted compositional ranges of Fe-Ni sulfides, the wide range for silicates, and the absence of hydrous phases indicate that comet Wild 2 experienced little or no aqueous alteration. Less abundant Wild 2 materials include a refractory particle, whose presence appears to require radial transport in the early protoplanetary disk. 相似文献
596.
Warren EH Vigneron NJ Gavin MA Coulie PG Stroobant V Dalet A Tykodi SS Xuereb SM Mito JK Riddell SR Van den Eynde BJ 《Science (New York, N.Y.)》2006,313(5792):1444-1447
CD8-positive T lymphocytes recognize peptides that are usually derived from the degradation of cellular proteins and are presented by class I molecules of the major histocompatibility complex. Here we describe a human minor histocompatibility antigen created by a polymorphism in the SP110 nuclear phosphoprotein gene. The antigenic peptide comprises two noncontiguous SP110 peptide segments spliced together in reverse order to that in which they occur in the predicted SP110 protein. The antigenic peptide could be produced in vitro by incubation of precursor peptides with highly purified 20S proteasomes. Cutting and splicing probably occur within the proteasome by transpeptidation. 相似文献
597.
598.
599.
600.
A. Warren 《Land Degradation \u0026amp; Development》2002,13(6):449-459
Land degradation cannot be judged independently of its spatial, temporal, economic, environmental and cultural context. Evaluations are therefore almost infinitely variable and very dynamic. These observations are examined in two contexts, first in two case studies. One, from the southern Levant, makes use of a long and well‐documented history of environmental assessment that varied greatly between communities. The other, from contemporary Niger, shows finer scale differences among villagers. Second, the dynamic and multiple assessment of futures (sustainability) is illustrated with data from the same case study in Niger. In this wider context, multiplicity and dynamicity are largely a consequence of the choice of model of the environmental or social future. The usually positive difference between large‐scale and finer scale assessments of degradation is dubbed the [social delivery ratio]. Simplified systems of evaluation may be necessary for allocation, but they need to be treated with great caution if the argument here is accepted. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献