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排序方式: 共有246条查询结果,搜索用时 78 毫秒
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Daniele Grifoni Marco Napoli Francesco Sabatini Simone Orlandini Marco Mancini Gaetano Zipoli Anna Dalla Marta 《Journal of Agronomy and Crop Science》2019,205(4):422-432
A UV exclusion experiment was conducted on durum wheat (Triticum durum Desf. var. Claudio) grown in pots. Plants were grown under three different radiative treatments in greenhouses covered with plastic filters: Teflon, transparent to the entire region of natural UV‐visible sunlight (TEF); polyester, transparent above 312 nm (MYL, excluding UVB) and Lee, transparent above 400 nm (LEE, excluding both UVA and UVB). Analyses have been carried out to determine the concentration of photosynthetic pigments in leaves, UV‐absorbing compounds, nitrogen and carbon in leaves, culms and spikes and proteins and gluten in grains. In particular, plants grown under UV exclusion showed a reduction in protein and dry gluten content (consequently without variation in the ratio dry gluten/protein), but at the same time, a significant increase of gluten index, which is a parameter to define the quality of gluten, was observed. The results highlighted the influence played by UV radiation on some biochemical parameters, mainly UV‐absorbing compounds, leaf nitrogen and grain protein characteristics of durum wheat cultivated under Mediterranean conditions. In particular, natural level of UV in the Mediterranean improves the characteristics of durum wheat flour important for pasta production (high dry gluten level), while the UV exclusion could improve characteristics of flour important for bread production (high gluten index). 相似文献
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A procedure was developed to obtain non-embryogenic callus and regenerated lines from root segments of Zea mays grown in aseptic conditions. The activity of glutathione-S-transferases (GSTs), for non-embryogenic callus, was determined toward 1-chloro-2,4-dinitrobenzene (CDNB) and it was compared with that obtained for corn seedlings grown without hormones. For the callus masses, increases of specific activity toward CDNB and the kinetic parameter Vmax were observed with respect to corn seedlings. The procedure permitted the regenerating of tissues from callus explants, therefore the GST(CDNB) activity and the effect of the safener benoxacor on its expression were investigated for the regenerated tissues grown in agarized substrate and in liquid medium. These explants showed a constitutive GST(CDNB) activity higher than corn seedlings and this activity was increased, for both tissues, in response to the presence of the safener benoxacor in the growing medium. The GST activity for the above tissues was also assayed toward benoxacor and terbuthylazine, metolachlor and fluorodifen herbicides. Measurable GST activity was found toward some of the above chemicals and it was found to be significantly enhanced in response to benoxacor treatment. 相似文献
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Mologni Omar Lyons C. Kevin Marchi Luca Amishev Dzhamal Grigolato Stefano Cavalli Raffaele Röser Dominik 《European Journal of Forest Research》2021,140(4):745-759
European Journal of Forest Research - The growing interest in accessing steep terrain is pushing the expansion of the operating range of ground-based machines through winch-assist technology.... 相似文献
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Silvio Peixoto Ronaldo O. Cavalli Dariano Krummenauer Wilson Wasielesky Fernando D''Incao 《Aquaculture (Amsterdam, Netherlands)》2004,230(1-4):197-204
The application of artificial insemination techniques as a way to overcome the lack of mating of the closed thelycum Farfantepenaeus paulensis under large scale conditions is reported. The performance of artificially inseminated females (49.4±11.6 g) maintained in conventional versus unisex maturation systems was compared. Groups of unilaterally eyestalk-ablated females were artificially inseminated with one compound spermatophore soon after molting. The percentage of fertilized spawns increased from 26% before the use of artificial insemination to 57% afterwards. The reproductive performance of inseminated females held in conventional or unisex maturation systems showed no significant differences. Artificial insemination was considered a practical approach to overcome the lack of mating of F. paulensis under large-scale conditions with acceptable reproductive performance. The results also indicate the possibility of holding females separately from males, which could mean significant improvements in maturation systems through the increase in the stocking density of spawning females. 相似文献
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Sandro Froehner Daniele Botelho Souza Karina Scurupa Machado Edson Cordova da Rosa 《Water, air, and soil pollution》2010,210(1-4):33-41
The Barigüi River watershed is located in the metropolitan region of Curitiba, Southern Brazil, passing through several neighboring counties. In recent years, due to growth and disorderly occupation along the river, in addition to lack of sanitation, the Barigüi River suffered a very large inflow of untreated domestic wastewater. Current programs to monitor the watershed use traditional physical–chemical parameters. Here, the presence of some molecular tracers found in domestic effluents was investigated, such as caffeine and coprostanol at some selected sites in Barigüi River. Caffeine is highly soluble in water and its presence in water bodies is due to the disposal of untreated sewage. Caffeine is eliminated in the urine (approximately 0.5% to 10% of the consumption). The samples were collected in three campaigns, two in dry weather and another during a week in the rainy season. The results showed that caffeine concentration ranged between zero and 753.5 μg g?1. Higher values were found on rainy days. Caffeine showed a positive correlation between BOD and nitrate; it also showed a positive correlation with coprostanol, a fecal biomarker. Finally, caffeine has been shown to be a good parameter to determine the contamination by domestic wastewater. 相似文献
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Silvio Peixoto Wilson Wasielesky Jr Fernando D'Incao Ronaldo O. Cavalli 《Journal of the World Aquaculture Society》2003,34(1):50-56
The reproduction of wild-caught Farfantepenaeus paulensis in captivity has been successfully achieved since 1983. However, year-round supply of wild broodstock is costly and unpredictable. This study compares the reproductive performance of animals of similar size (females from 32–33 g and males from 19–21 g) but from different sources: estuary-caught juveniles reared indoors for 9 mo and wild-caught adults from shallow coastal waters. Groups of 20 males and 30 unilaterally eyestalk-ablated females were maintained for 60 d in four maturation tanks under controlled environmental conditions. A higher number of eggs per spawning event (78,414 ± 34,491) and total egg production (4,469,600) were observed for the wild females. Nevertheless, captive females produced a higher number of nauplii (1,788,259) due to their higher percentage of fertilized spawns. Therefore, within the size range of this study, the reproductive performance of estuary-caught F. paulensis juveniles over-wintered indoors was found to be equivalent to that of wild-caught females from shallow coastal waters. 相似文献
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Maria?Teresa?Dell'AbateEmail author Anna?Benedetti Alessandra?Trinchera Daniele?Galluzzo 《Biology and Fertility of Soils》2003,37(2):124-129
Carbon and nitrogen mineralisation of leather meal fertilisers were studied in two soils characterised by different respiration activity. Both C and N mineralisation were highest in the most active soil, and when leather meal was added as a powder rather than as 2- to 4- and 4- to 6-mm particles. Fast and slow soluble N pools were determined after extraction with cold water and with hot buffer, respectively. The N remaining after the second extraction with hot buffer was named slow-release N. The percentage of slow-release N rose as the size of the applied leather meal particles increased, whereas fast soluble N was highest in the coarsest (4-6 mm) fertiliser. 相似文献