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Cao Dinh Hung Chang-Hee Hong Seon-Ki Kim Kyu-Han Lee Jea-Young Park Min-Woo Nam Dae-Ho Choi Hye-In Lee 《Acta Physiologiae Plantarum》2016,38(6):152
Light-emitting diodes (LEDs) are useful for the growth of many plants, but not known for blueberry species. This study examined the effects of fluorescent lamps and 100 % red, 80 % red plus 20 % blue, 50 % red plus 50 % blue, and 100 % blue LEDs on the growth and development of highbush blueberry shoots under aseptic and non-aseptic conditions. Results revealed that monochromatic blue LEDs accumulated the highest contents of leaf chlorophylls. In contrast, monochromatic red LEDs inhibited chlorophyll accumulation, but produced the longest shoots and roots and provided high percentages of side shoot formation from ex vitro plants. Mixed LEDs, particularly 50 % red plus 50 % blue light, improved plant growth with respect to notably increased shoot and root biomass. Direct rooting of in vitro shoots under non-aseptic conditions was readily achieved using a commercial mixture of perlite and peat moss with high humidity controls. These findings obviously suggest the efficient use of LEDs to replace traditional fluorescent lamps in large-scale propagation of the highbush blueberry, and also pave the way for future studies on LEDs for standardizing micropropagation protocols to shrub crops and woody plants. 相似文献
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Nèjia Farhat Amine Elkhouni Walid Zorrig Abderrazak Smaoui Chedly Abdelly Mokded Rabhi 《Acta Physiologiae Plantarum》2016,38(6):145
Magnesium nutrition is often forgotten, while its absence adversely affects numerous functions in plants. Magnesium deficiency is a growing concern for crop production frequently observed in lateritic and leached acid soils. Competition with other cations (Ca2+, Na+, and K+) is also found to be an essential factor, inducing magnesium deficiency in plants. This nutrient is required for chlorophyll formation and plays a key role in photosynthetic activity. Moreover, it is involved in carbohydrate transport from source-to-sink organs. Hence, sugar accumulation in leaves that results from the impairment of their transport in phloem is considered as an early response to Mg deficiency. The most visible effect is often recorded in root growth, resulting in a significant reduction of root/shoot ratio. Carbohydrate accumulation in source leaves is attributed to the unique chemical proprieties of magnesium. As magnesium is a nutrient with high mobility in plants, it is preferentially transported to source leaves to prevent severe declines in photosynthetic activity. In addition, Mg is involved in the source-to-sink transport of carbohydrates. Hence, an inverse relationship between Mg shortage and sugar accumulation in leaves is often observed. We hereby review all these aspects with a special emphasis on the role of Mg in photosynthesis and the structural and functional effects of its deficiency on the photosynthetic apparatus. 相似文献
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Teodora Popova Stanislava Grozeva Velichka Todorova Gergana Stankova Nikolay Anachkov Velichka Rodeva 《Acta Physiologiae Plantarum》2016,38(11):273
Anther culture is one of the most important and useful tool to create pure lines for plant breeding programs rapidly. Some pepper genotypes are recalcitrant and embryogenic frequency in anther culture is still low or reaction is not observed at all. Temperature stress (low or high) can facilitate switching the microspore to sporophyte developmental pathway. In this study, some differences were found in embryogenic reaction among the pepper genotypes and culture media variants, depending on duration of cold treatment of flower buds. Experimental results indicated that embryogenic efficiency decreased under low-temperature stress. Nevertheless, positive effect of cold pretreatment on direct embryo induction was obtained in four genotypes—cultivar Hebar, hybrid 50/01 and lines 668/02 and 1312/02. Increasing of embryogenic reaction after cold pretreatment was observed in media variants C (24 h) and MS-3 + (24 and 48 h), while on medium variant C-0 direct embryo formation was registered only after 48 h cold pretreatment. These results show that the donor genotypes have specific requirements for type and duration of temperature pretreatment and also culture media for induction of androgenesis with higher frequency. 相似文献
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Marc Artiga 《Biology & philosophy》2016,31(4):483-505
Naturalistic theories of representation seek to specify the conditions that must be met for an entity to represent another entity. Although these approaches have been relatively successful in certain areas, such as communication theory or genetics, many doubt that they can be employed to naturalize complex cognitive representations. In this essay I identify some of the difficulties for developing a teleosemantic theory of cognitive representations and provide a strategy for accommodating them: to look into models of signaling in evolutionary game theory. I show how these models can be used to formulate teleosemantics and expand it in new directions. 相似文献
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Olga Maslova Oleg Fedevych Nadiia Shuvalova Olena Deryabina Volodymyr Zhovnir Miroslav Novak Peter Kruzliak 《Cell and tissue banking》2016,17(2):335-339
The need for selection of the optimal material for the manufacturing of cardio-patches can be resolved by the use of cryostored autologous pericardial tissue. This short communication is a concise fragment of a large-scale research and demonstrates only the efficiency of cell culturing before and after pericardial preservation in the low temperature conditions. 相似文献
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Despite a recent surge of interest in temporary lentic systems, a strong theory linking the biota to its environment has not
emerged. Using data from 10 temporary ponds at Mammoth Cave National Park, Kentucky, USA, we investigated how invertebrate
communities were structured along environmental gradients, both between and within ponds. Samples were collected with a benthic
corer in winter and spring, and a sweep net in spring. Six between-pond and two within-pond datasets were created. Between-pond
analyses yielded significant CCA’s with only one of the six data sets. The ranges of environmental variables (EV’s) within
ponds were often similar to the ranges of EV’s when averaged and compared between ponds. Some taxa were aggregated in a single
pond, and richness increased with pond area. The theory that richness increases with hydroperiod did not apply to these systems.
Within-pond analyses yielded more consistent relationships, with both CCA’s being significant. Sample depth was the best predictor
of invertebrate richness and abundance, with most taxa preferring shallow habitats. Richness and abundance were higher in
both shallow ponds and shallow areas of deep ponds than in deep areas of deep ponds. Standardizing sample depth may be an
effective way to remove this gradient as a confounding variable in future research. The presence of within-pond gradients,
possibly coupled with the limited dispersal and random colonization of tolerant taxa, makes between-pond comparisons difficult.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorised users.
Handling editor: S. Declerck 相似文献
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