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101.
102.
The Arabian Seas Region plays an important role in the global landings and trade of sharks and rays. The United Arab Emirates (UAE) and Yemen, two countries with stark socio‐economic differences, serve as major regional trade hubs for shark and ray products and four countries (Oman, Pakistan, UAE and Yemen) supply nearly 11% of dried fin exports to Hong Kong. Yet, little information is available on the characteristics of this trade and the fisheries contributing to it. Here, we review the fisheries characteristics, trade, utilization and distribution chain of sharks and rays in 15 countries of the Arabian Seas Region based on published and grey literature, landing surveys, field observations and interviews with fishermen and traders. Although regional shark fisheries remain mostly artisanal, reported shark and ray landings represent 28% of the regional total fish production, reaching 56,074 mt in 2012 (7.3% of total world catches), with Iran, Oman, Pakistan and Yemen ranking as the primary catchers. Utilization and distribution patterns are complex, vary between landing sites and countries, and remain unmonitored. Based on widespread over‐exploitation of most teleost fisheries, current exploitation levels for most sharks and rays are potentially unsustainable. The situation is exacerbated by limited research and political will to support policy development, the incomplete nature of fisheries data, as well as insufficient regulations and enforcement. A better understanding of shark and ray fisheries will be key for regulating trade, promoting conservation and developing management initiatives to secure food security, livelihoods and biodiversity conservation in the region. 相似文献
103.
Manuel Soto-Dávila Danixa Martinez Ricardo Oyarzún Juan P. Pontigo Carolina Vargas-Lagos Francisco J. Morera Julia Saravia Fábio Zanuzzo Luis Vargas-Chacoff 《Journal of fish diseases》2020,43(1):111-127
Pathogen interactions with cultured fish populations are well studied, but their effects on native fishes have not been characterized. In Chile, the disease caused by bacterial species Piscirickettsia salmonis represents one of the main issues and is considered to be one of the important pathogens in the field of aquaculture. They have been found to infect native fish. Therefore, it is necessary to understand the impact of P. salmonis on native species of local commercial value, as well as the potential impact associated with the emergence of antibiotic-resistant strains of P. salmonis. Due to this purpose, the native fish Eleginops maclovinus was used in our study. Fish were randomly distributed in tanks and intraperitoneally inoculated with two strains of P. salmonis. No mortality was recorded during the experiment. Cortisol, glucose and total α-amino acid levels increased in fish injected with AUSTRAL-005 strain compared to sham-injected and LF-89-inoculated fish. Moreover, results showed an increase in the activity of carbohydrates and lipids metabolism in liver; and an increase in the carbohydrates, lipids and total α-amino acid metabolism in muscle after injection with AUSTRAL-005. Our results suggest that P. salmonis modulates the physiology of E. maclovinus and the physiological impact increase in the presence of the antibiotic-resistant strain AUSTRAL-005. 相似文献
104.
Potato (Solanum tuberosum L.) is a major food and cash crop mainly grown by small-scale farmers in the highland regions of Uganda. Changing global weather patterns require varieties that are able to grow within the short rainfall cycles and yield optimally under the prevailing conditions. The objectives of this study were to estimate the combining ability effects for early maturity, yield and yield related traits in potato. Eighteen F1 families generated from two sets of 12 parents using a North Carolina Design II were evaluated for days to 50% flowering, leaf senescence, yield and yield related traits in two different locations. Both additive and non-additive genetic effects influenced the expression of traits. However, additive genetic effects were predominant over the non-additive for most of the traits. The GCA/SCA ratios were 0.68 and 0.78 for days to 50% flowering and average tuber weight. Broad sense heritability estimates were 0.70 for total tuber weight and 0.78 for days to 50% flowering. The predominance of additive genetic effects imply that, genetic gains can be achieved through different selection methods and traits transferred to the respective progenies. Parents Rwangume, 396,038.107, 395,011.2, NKRK19.17, 393,077.54, Kimuri, and 392,657.8 had desirable GCA effects for the number of days to flowering and yield related traits. Families of Rwangume?×?NKRK19.17, 393,077.54?×?395,011.2, 396,038.107?×?Rwangume and 396,038.107?×?395,011.2 had desirable SCA effects for yield and number of days to 50% flowering. The selected parents and families will be subjected to further clonal evaluation and selection. 相似文献
105.
Faba bean (Vicia faba L.) has high utility as a food and soil fertility improving crop. One of the major fungal pathogens of faba bean is Botrytis fabae, the causative agent of chocolate spot. The disease affects significantly the leaf, stem, pod and seed of faba bean compromise its productivity in the smallholder farming sector. Nonetheless, there are limited resistant/tolerant faba bean varieties available and disease control technology options. Therefore, it was prudent to evaluate faba bean landraces for chocolate spot resistance. Fifty landraces together with ten improved varieties were evaluated both in the field and in the greenhouse under natural and artificial inoculation with previously selected aggressive Botrytis fabae isolate (Iso-016) from West Gojjam, in Ethiopia. There were highly significant differences (p?<?0.001) among the landraces for reaction to the disease and agronomic traits. Significant positive correlation was recorded between reaction of genotypes in the field and greenhouse disease data. The overall mean disease epidemics varied from 92.5 to 697.5 for the area under disease progress curve (AUDPC). The highest level of resistance was found in the ICARDA lines, ILB-4726, ILB-938 and BPL-710. Of all 18 landrace collections displayed significantly lower disease reaction than the susceptible check. However the resistance was moderate. The selected eighteen landraces will be recommended for use in breeding for chocolate resistance. Overall, resistance was highly heritable, suggesting that phenotypic selection can be exploited to improve chocolate spot resistance in faba bean varieties. 相似文献
106.
107.
108.
Optimizing nitrogen use efficiency in wheat and potatoes: interactions between genotypes and agronomic practices 总被引:1,自引:0,他引:1
Eleanor Y. Swain Leonidas Rempelos Caroline H. Orr Gavin Hall Rachel Chapman Mftah Almadni Elizabeth A. Stockdale Jonathan Kidd Carlo Leifert Julia M. Cooper 《Euphytica》2014,199(1-2):119-136
One approach to decrease the environmental impact of crop production and reduce costs is to optimize agronomic practices and genotypes so that nutrients are used more efficiently. In this study the effects of agronomic practices (rotations, crop protection, fertilization) on yields, nitrogen use efficiency (NUE) and associated parameters were studied in an experiment using two winter wheat genotypes (Cordiale and Scaro) in one season and two potato genotypes (Sarpo Mira and Sante) in two seasons. The wheat showed no varietal differences in yield and NUE; instead the fertilization regime was the main factor affecting yield and NUE with higher values observed when conventional fertilization was used. The exception was for wheat grown after three years grass/clover ley when there was no added yield benefit from conventional fertilization of the organically bred variety (Scaro). This demonstrates the potential for N fixing crops to provide sufficient N to high yielding cereals if grown for long enough prior to planting. The greatest gains in NUE were achieved by combining an N efficient genotype with conventional crop management in an organic rotation. Fertilization and genotypic variation were the main factors affecting potato tuber yield and NUE, with the late maturing Sarpo Mira displaying elevated yields and NUE compared with the early maturing Sante. The use of organic fertility sources resulted in lower NUE, but N release from organic sources may increase NUE of future crops. This highlights the need for long-term nutrient balance and modelling studies to assess NUE at the crop rotation scale. 相似文献
109.
Water, Air, & Soil Pollution - Nineteen soil samples (SE Spain) with very different chemical physical properties and developed over different parent materials were contaminated by adding... 相似文献
110.
Julia B. Montgomery Wendy M. Duckett Andrea C. Bourque 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(7):751-754
A 6-year-old mare was presented for evaluation of dysuria and pollakiuria. A
pelvic mass, which caused obstruction of urinary outflow, was identified.
Evidence of renal failure was also present. Due to poor prognosis the mare was
euthanized. A postmortem examination revealed a pelvic lymphoma that surrounded
and compressed the urethra. 相似文献