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11.
Utilization of the genetic resources of wild species to create a nontransgenic high flavonoid tomato
Willits MG Kramer CM Prata RT De Luca V Potter BG Steffens JC Graser G 《Journal of agricultural and food chemistry》2005,53(4):1231-1236
Flavonoids represent a large and important group of plant natural products that are ubiquitous in the plant kingdom. Epidemiological studies have shown the health benefits of a diet high in flavonoids. However, the dietary intake of flavonoids in most western populations is limited, creating a need to find alternative food sources for these polyphenolic secondary metabolites. The domestication of many of our cultivated food crops has resulted in alterations in the biosynthetic pathways of many essential micronutrients and vitamins through inadvertent counterselection against nutritional traits in favor of agronomic ones. Flavonoids are nearly absent from fruits of cultivated tomato (Lycopersicon esculentum Mill.), a major vegetable in human diets. Previous attempts to restore the flavonoid pathway in tomato fruits have been limited to transgenic strategies, suggesting that the problem was intractable through traditional methods. Here, we describe for the first time a nontransgenic metabolic engineering approach to developing a high flavonoid tomato using a wild tomato species (Lycopersicon pennelliiv. puberulum) and demonstrate the opportunities for restoring functional pathways using the genetic resources of wild species, resulting in production of healthier foods. 相似文献
12.
A model for optimal operation of water supply/irrigation systems of various water quality sources, with treatment plants, multiple water quality conservative factors, and dilution junctions is presented. The objective function includes water cost at the sources, water conveyance costs which account for the hydraulics of the network indirectly, water treatment cost, and yield reduction costs of irrigated crops due to irrigation with poor quality water. The model can be used for systems with supply by canals as well as pipes, which serve both drinking water demands of urban/rural consumers and field irrigation requirements. The general nonlinear optimization problem has been simplified by decomposing it to a problem with linear constraints and nonlinear objective function. This problem is solved using the projected gradient method. The method is demonstrated for a regional water supply system in southern Israel that contains 39 pipes, 37 nodes, 11 sources, 10 agricultural consumers, and 4 domestic consumers. The optimal operation solution is described by discharge and salinity values for all pipes of the network. Sensitivity of the optimal solution to changes in the parameters is examined. The solution was found to be sensitive to the upper limit on drinking water quality, with total cost being reduced by 5% as the upper limit increases from 260 to 600 mg Cl l–1. The effect of income from unit crop yield is more pronounced. An increase of income by a factor of 20 results in an increase of the total cost by a factor of 3, thus encouraging more use of fresh water as long as the marginal cost of water supply is smaller than the marginal decrease in yield loss. The effect of conveyance cost becomes more pronounced as its cost increases. An increase by a factor of 100 results in an increase of the total cost by about 14%. The network studied has a long pipe that connects two distinct parts of the network and permits the supply of fresh water from one part to the other. Increasing the maximum permitted discharge in this pipe from 0 to 200 m3 h–1 reduces the total cost by 11%. Increasing the maximum discharge at one of the sources from 90 to 300 m3 h–1 reduces the total cost by about 8%. 相似文献
13.
A 2 1/2-month-old, female German Shepherd Dog was examined because of incontinence since birth. Multiple urinary anomalies which included left renal agenesis, right hydronephrosis and hydroureter and urinary bladder dysfunction were found by excretory urography. These abnormalities were confirmed at necropsy. In addition, vesicovaginal continuity with apparent absence of the urethra was also found 相似文献
14.
Yohannes Misskire Tekalign Mamo Abi M. Taddesse Uri Yermiyahu 《Journal of plant nutrition》2019,42(4):307-322
Vertisols are characterized by deficiency of nutrients and recently, potassium (K), a major plant nutrient in crops, is gaining attention because of crop removal, fixation by clay minerals and leaching. A field experiment was conducted during the 2015 and 2016 main cropping seasons to test the effect of potash fertilizer on Vertisols of East Gojjam at Gudalima and Dejen/Tik sites using teff crop. The K rates (applied as muriate of potash) were 0, 50,100, and 150?kg ha?1. The experiment was laid out in a randomized complete block design in three replications. The results indicated that the plant height, panicle length, number of effective tillers, dry matter and grain yield of teff increased significantly (P?<?0.05) with applied K. The highest dry matter and grain yield (6966.4 and 2418.2 kg ha?1, respectively) were obtained from the application of 100 kg ha?1 KCl. Total uptake of N, P, and K were enhanced significantly with K treated plots than those without and K efficiency was improved due to the rate of K. The present study demonstrated the importance of K application to supplement NPS for optimum dry matter and grain yield of teff on Vertisols of the study sites. 相似文献
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Improving the sustainability of irrigation systems requires the optimization of operational parameters such as irrigation threshold and irrigation amount. Numerical modeling is a fast and accurate means to optimize such operational parameters. However, little work has been carried out to investigate the relationship between irrigation scheduling, irrigation threshold, and irrigation amount. Herein, we compare the results of HYDRUS 2D/3D simulations with experimental data from triggered drip irrigation, and optimize operational parameters. Two field experiments were conducted, one on loamy sand soil and one on sandy loam soil, to evaluate the overall effects of different potential transpiration rates and irrigation management strategies, on the triggered irrigation system. In both experiments, irrigation was controlled by a closed loop irrigation system linked to tensiometers. Collected experimental data were analyzed and compared with HYDRUS 2D/3D simulations. A system-dependant boundary condition, which initiates irrigation whenever the matric head at a predetermined location drops below a certain threshold, was implemented into the code. The experimental model was used to evaluate collected experimental data, and then to optimize the operational parameters for two hypothetical soils. The results show that HYDRUS 2D/3D predictions of irrigation events and matric heads are in good agreement with experimental data, and that the code can be used to optimize irrigation thresholds and water amounts applied in an irrigation episode to increase the efficiency of water use. 相似文献
17.
Brenner J Orgad U 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(1):141-143
An epidemiological investigation of an outbreak of intestinal atresia in Israeli Holstein-Friesian newborn calves showed a linkage with rectal palpation for early pregnancy diagnosis, performed less than 42 days after insemination. The odds of an exposed calf, i.e., one born to a dam that was diagnosed by early palpation as having intestinal atresia were 119.7 times higher than one born in normal control herds (95% CI; 7.4-1946.3). A total of 682 calves-at-risk was recorded from mid-1998 to mid-2000 and a total of 47 calves (6.9%) were born with intestinal atresia during this period. Two forms of intestinal atresia were recognized at post-mortem: atresia coli and atresia ilei. 相似文献
18.
Uri Bargai VMD AB DVSc Theodor Nobel DVM† Shmuel Pearl DVM† 《Veterinary radiology & ultrasound》1984,25(5):235-239
Ten beef bulls infected with Besnoitiosis were examined radiographically and pathologically. Eight of these were slaughtered soon after diagnosis; two were left for a six-month observation period. The radiographic findings were focal and branching-tree calcification of the testes. Histopathologic examination proved these calcifications to be necrotic sections of the seminiferous tubules. Radiography of the testes as a means of evaluating the fertility status of the infected bull is recommended. 相似文献
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20.
Bruno C. Perez Julio C. C. Balieiro Roberto Carvalheiro Fabio Tirelo Gerson A. Oliveira Junior Juliana M. Dementshuk Joanir P. Eler Jos B. S. Ferraz Ricardo V. Ventura 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(1):23-39
The objective of the present study was to investigate the impact of considering population structure in cow genotyping strategies over the accuracy and bias of genomic predictions. A small dairy cattle population was simulated to address these objectives. Based on four main traditional designs (random, top‐yield, extreme‐yield and top‐accuracy cows), different numbers (1,000; 2,000 and 5,000) of cows were sampled and included in the reference population. Traditional designs were replicated considering or not population structure and compared among and with a reference population containing only bulls. The inclusion of cows increased accuracy in all scenarios compared with using only bulls. Scenarios accounting for population structure when choosing cows to the reference population slightly outperformed their traditional versions by yielding higher accuracy and lower bias in genomic predictions. Building a cow‐based reference population from groups of related individuals considering the frequency of individuals from those same groups in the validation population yielded promising results with applications on selection for expensive‐ or difficult‐to‐measure traits. Methods here presented may be easily implemented in both new or already established breeding programs, as they improved prediction and reduced bias in genomic evaluations while demanding no additional costs. 相似文献