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981.
Kalanchoe blossfeldiana transformed with rol genes, termed root-inducing (Ri) lines, which had been produced through transformation using Agrobacterium rhizogenes wild-type strain ATCC15834, were tested for their postharvest performance. Flower longevity, ethylene sensitivity and display quality varied among control and chemical growth retarded plants and the Ri lines. Both chemical growth retardation and transformation with rol genes reduced the number of flowers in comparison to control plants. Detached single flowers of the two Ri lines tested, Ri line 306 and 331, had a longevity, defined as the stage where the flowers were 70% open, of 32 and 34 d, respectively, whereas chemical growth retarded and control plants had a longevity of 28 and 26 d, respectively. Ri line 331 had the significantly longest display life of 34 d to reach the stage of losing the ornamental value of the whole plant, defined as 10% wilted flowers. The corresponding display life of control and chemical retarded plants and plants of Ri line 306 was 25 d. The opening of the flowers was more synchronous in the Ri lines than control plants. Exposed to ethylene, the flowers of the Ri lines exhibited reduced responsiveness whereas chemical growth retarded and control plants were sensitive. Possible mechanisms behind the improved postharvest performance of plants transformed with rol genes are discussed. 相似文献
982.
Menghe H. Li Edwin H. Robinson Daniel F. Oberle Penelope M. Lucas Brian G. Bosworth 《Journal of the World Aquaculture Society》2012,43(1):107-113
This study examined the use of corn gluten feed (CGF) and cottonseed meal (CSM) to partially replace soybean meal and corn in diets for pond‐raised hybrid catfish, Ictalurus punctatus×I. furcatus. Five 28% protein diets containing various combinations of CGF and CSM were evaluated. Fingerling hybrid catfish (mean initial weight: 45 g/fish) were stocked into 25, 0.04‐ha ponds at a rate of 14,826 fish/ha. Fish were fed once daily to apparent satiation for a 179‐d growing season. CGF at 30% of the diet (10% CSM) and a combination of CGF and CSM up to 25% each did not affect physical quality (percentages floatability and feed dust) of the diet. No significant differences were observed in total amount of diet fed, net yield, diet consumption, weight gain, feed conversion ratio (FCR), survival, and fillet proximate nutrient composition among fish fed various diets. Results show that hybrid catfish can utilize CGF at levels up to 30% of the diet (10% CSM), and a combination of CGF and CSM up to 25% each without significantly affecting growth, diet consumption, FCR, and fillet proximate nutrient composition. However, a combination of CGF and CSM at 20% each and above reduced carcass yield. 相似文献
983.
Copper oxide nanoparticles were immobilized on quartz sand and their catalytic activity for the degradation of an organic dye was investigated. The use of nanoparticles as catalysts for non photo-induced oxidation of water contaminants is relatively new. The CuO catalyst has shown promising results when suspended in free form in batch systems. Because heterogeneous catalysis is often the preferred mode of operation for application of catalytic technology, we studied the effect of immobilization of the nanoparticles on quartz sand in a flow-through system and its implication for the catalytic process. The coated sand was packed in a column and its catalytic activity for the degradation of an organic dye was investigated in a series of flow-through experiments with hydrogen peroxide as the oxidant. Control experiments with uncoated sand were also performed for comparison. The coated sand demonstrated high catalytic ability, achieving complete oxidation of the dye. During the reaction, CO2 was produced, leading to a decrease in the water saturation in the column and reduced contact surface between the nano-CuO catalysts and the dye solution. The degradation was improved by enabling a longer residence time of the dye in the column, yielding up to 85% degradation of the dye. These results suggest that CuO nanoparticle-coated sand is an efficient catalyst for complete degradation of the organic dye. 相似文献
984.
Hydrocarbon and Toxic Metal Contamination from Tank Installations in a Northwest Greenlandic Village
Janne Fritt-Rasmussen Pernille Erland Jensen Rune Haubo Bojesen Christensen Ingela Dahll?f 《Water, air, and soil pollution》2012,223(7):4407-4416
Contamination from tank installations in the Arctic is an important issue, since tanks are a necessary feature of all communities, and may be a source of local pollution. Soil samples from below and around three tank installations and one reference site in the Northwest Greenlandic village of Tasiusaq were analysed for the total content of hydrocarbons (THC), lead, cadmium and organic content in the soil. Concentrations up to 77,000?mg/kg DW THC were found, mainly as weathered oil products. Elevated levels of lead and cadmium were also found in many of the samples, with concentrations up to 300 and 2?mg/kg DW, respectively. The tank installation areas were contaminated by THC, lead and cadmium compared to the reference site, and parts of the areas were highly contaminated, exceeding the Danish environmental quality criteria. The correlation between lead and cadmium concentrations was significant (p?<?0.01), while no correlation existed between THC and organic matter. Small spills from daily use of the tank installations are suggested to be the source of the THC contamination, whereas the lead and cadmium contamination is suggested to originate primarily from the plume of smoke from waste incineration. 相似文献
985.
R. Brand Phillips Brian D. Cooke Victor Carrión Howard L. Snell 《Biological conservation》2012,147(1):264-269
Alien species can negatively affect global biodiversity, especially on islands. Significant advances in methods for eradicating mammals from islands have been achieved. In contrast, development of methods for eradicating birds from islands has lagged and few islands have had alien birds successfully eradicated. We report on a 7 year campaign to remove rock pigeons from the Galapagos Islands. To date this is the largest successful eradication of an alien bird from an island system and the only eradication of rock pigeons from an island. Multiple methods were tested and used, including alpha-chloralose, however, shooting with a high-powered air rifle was the most efficient removal technique. Incorporating the support of the community and local agencies into the campaign was critical to the success of the project. 相似文献
986.
Esmaeil S. Nadimi Ole Green Victoria Blanes-Vidal Jakob J. Larsen Lars P. Christensen 《Biosystems Engineering》2012,112(3):236-247
Animal forage plays an important role in agriculture. To maintain the silage quality during storage, preserving it from decomposition by wrapping the harvested crop with plastic stretch film is crucial. Any failure in the preserving process permits the infusion of oxygen, which allows the growth of undesirable aerobic microorganisms and silage decomposition. To study the state of the silage, temperature inside the stack could be used as indicator of decomposition. However, no previous study has developed a model that can detect decomposition based on abnormal temperature variations inside a silage stack. The first objective of this paper was to develop a structured nonlinear model to estimate the dynamics of temperature variations measured by a wireless sensor network-based monitoring system (nRF95E) inside a silage bale and stack prior to the decomposition process. The requirement of a robust nonlinear model is that sensor nonlinearities that are inherent in nature are considered. The results showed that a Hammerstein-Wiener (HW) model with sigmoid network performed the best in terms of percentage of fit (91.70%) between the measured and simulated output. The second objective was to estimate the length of time required to detect the decomposition process after the airtight seal was punctured using the model. The error between the predicted model output and the sensor readings exceeded a preset threshold interval 17 days after the cover film was punctured and 9 days after the decomposition process was detected due to the odour released. 相似文献
987.
Biochemical characterization of QTLs associated with endosperm modification in quality protein maize
Nancy Y. Salazar-Salas Karen V. Pineda-Hidalgo Jeanett Chavez-Ontiveros Roberto Gutierrez-Dorado Cuauhtémoc Reyes-Moreno Luis A. Bello-Pérez Brian A. Larkins Jose A. Lopez-Valenzuela 《Journal of Cereal Science》2014
Genetic analysis using quality protein maize (QPM) recombinant inbred lines derived from K0326Y QPM and W64Ao2 identified three quantitative trait loci (QTL) in bins 1.06, 7.02 and 9.03 associated with opaque2 endosperm modification. We evaluated the effects of these QTLs on protein accumulation and starch physicochemical properties. The QTL in bin 1.06 is close to α-zein genes, and vitreous individuals with this QTL had increased accumulation of 19-kDa α-zein, 27-kDa γ-zein and legumin-1. The QTL in bin 7.02 corresponds to the γ-zein locus, and greater accumulation of this protein was found in vitreous individuals. The QTL in bin 9.03 is close to starch biosynthetic genes; greater accumulation of granule-bound starch synthase and amylose was observed in vitreous kernel samples with this locus and that in bin 1.06, as well as less gelatinization enthalpy and crystallinity. Vitreous kernels contained angular-shaped/compact starch granules and more short-intermediate length chains of amylopectin. These results support that endosperm modification in QPM is associated with increased accumulation of γ-zein and other storage proteins, but also show that synthesis of less crystalline starch with more amorphous regions at the periphery of granules, which favor their packing and association with endosperm proteins, may also be an important factor. 相似文献
988.
Adusei-Fosu Kwasi Rolando Carol A. Richardson Brian van Leeuwen Rebecca Gaskin Robyn Bader Martin K.-F. Pathan Amin K. 《植物病害和植物保护杂志》2021,128(6):1501-1515
Journal of Plant Diseases and Protection - Myrtle rust is a serious fungal disease caused by Austropuccinia psidii affecting a number of Myrtaceae species in New Zealand and elsewhere. Control with... 相似文献
989.
990.