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991.
Sorghum [(Sorghum bicolor L.) Moench] is a highly productive crop plant, which can be used for alternative energy resource, human food, livestock feed or industrial purposes. The biomass of sorghum can be utilized as solid fuel via thermochemical routes or as a carbohydrate substrate via fermentation processes. The plant has a great adaptation potential to drought, high salinity and high temperature, which are important characteristics of genotypes growing in extreme environments. However, the climate change in the 21st century may bring about new challenges in the cultivated areas. In this review, we summarize the most recent literature about the responses of sorghum to the most important abiotic stresses: nutrient deficiency, aluminium stress, drought, high salinity, waterlogging or temperature stress the plants have to cope with during cultivation. The advanced molecular and system biological tools provide new opportunities for breeders to select stress‐tolerant and high‐yielding cultivars. 相似文献
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994.
Abstract – Programmes of habitat restoration usually assume that the targeted populations will readily colonise the newly provided habitat. However, this assumption may not always hold, and the success of restoration may be impaired if the individuals are driven to aggregate in areas of the habitat already available instead of spreading to new ones. We investigated how weirs situated along a river could drive Atlantic salmon (Salmo salar) to aggregate their redds and tested whether aggregation intensified at low fish density. For this, we applied spatial point pattern analysis to a data set consisting on the distribution of salmon redds in a small river over 15 years (1992–2006). Within the habitat suitable for spawning, redds were significantly aggregated, especially in the first 15 morphodynamic units below weirs. Our results suggest that the constraint imposed by obstacles on redd distribution should be considered when conducting habitat restoration. 相似文献
995.
J. Adriana Sañudo-Barajas John Labavitch Carl Greve Tomás Osuna-Enciso Dolores Muy-Rangel Jorge Siller-Cepeda 《Postharvest Biology and Technology》2009,51(2):158-167
Cell wall disassembly in ripening climacteric fruit is a highly complex process where ethylene plays a crucial role. Ethylene inhibitors can be used to explore the changes in the cell wall matrix and cross-linked polysaccharides in ethylene-regulated processes. The results of applying the ethylene receptor blocking inhibitor 1-methylcyclopropene (1-MCP) and the ethylene-releasing compound ethephon (2-chloroethylphosphonic acid) indicate that softening of ‘Maradol’ papaya fruit is dependent on ethylene. When fruit were induced to ripen extensively by exposure to a high dose of ethephon, 1-MCP inhibited the subsequent softening dramatically, but when inhibition of the ethylene response was caused by application of 1-MCP, subsequent fruit treatment with ethephon promoted extensive loss of galactose from the water-soluble polysaccharides, but this was not accompanied by fruit softening. The cell wall changes accompanying normal fruit softening were pectin solubilization and polyuronide depolymerization and these processes occurred simultaneously. Polygalacturonase likely is responsible for the ripening-associated changes in ‘Maradol’ papaya fruit texture and pectin polymer integrity. An increase in extractable fruit polygalacturonase follows the increased presence of pectin-derived oligosaccharides. 相似文献
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G Barnabé 《Aquaculture (Amsterdam, Netherlands)》1979,16(4):369-374
This system uses the shelter of the harbour entrance and coastal polluted zones for aquaculture purposes. Water from the open sea is supplied by forced circulation to the rearing area, which is separated from harbour water by a plastic sheet. Rafts, enclosures or cages can be used for intensive rearing of mollusks or fish. 相似文献
999.
We studied changes in the parameters of the acid-base balance of the blood in cattle before animal transport to the slaughterhouses, after transport, after stunning and before bleeding. At the same time we studied the occurrence of DFD meat by measuring the pH value of the muscle and by determining the meat color. We found out that the disorder of acid-base balance was less manifest, with respect to the large capacity of the buffer systems of the blood, than the changes caused by glycogenolysis in the muscle. 相似文献
1000.
The percentual change in the content of pro-acrosin taking place in ram semen preserved for a short and long time was examined in the period from April to October. Two diluents for keeping semen at the temperature of 16 degrees C and one diluent for keeping semen at 3 to 4 degrees C were used in short-time preservation. The content of pro-acrosin was measured 2, 8 and 12 hours after dilution. The lactoso-yolk diluent and the diluent after Milovanov (1980) were used for cryopreservation. The content of pro-acrosin was examined before and after semen freezing. In short-time preservation, no statistically significant decrease of pro-acrosin content was demonstrated in the H Milch diluent (Peter, 1975) at the storage temperature of 16 degrees C and in the diluent after Milovanov (1980) at the temperature of 3 to 4 degrees C. In the diluent prepared after Milovanov (1980) a significant decrease of pro-acrosin content during preservation was recorded at the storage temperature of 16 degrees C. When the short-time preservation diluents were compared, significant differences in pro-acrosin content were found between them. In the long-time preservation diluents a significant difference in pro-acrosin content was found before and after semen freezing; the difference between the short- and long-time preservation diluents was also significant. A positive correlation was found between sperm activity and pro-acrosin content. 相似文献