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排序方式: 共有562条查询结果,搜索用时 15 毫秒
71.
Ivaniele Nahas Duarte Robson Thiago Xavier de Sousa Gaspar Henrique Korndörfer Hamilton Seron Pereira 《Journal of plant nutrition》2015,38(12):1961-1972
Millet is a grass that responds to potassium fertilization and Alfa 01 and Alfa 02 are potential sources of this nutrient. Thus, the aim of this study was to evaluate the potential of as potassium sources by measuring accumulation of this nutrient in millet. The crop was grown in Ustoxic Quartzipsamment (RQo) soil. The experiment was set up in randomized blocks with three repetitions. The treatments consisting of three sources (KCl, Alfa 02, Alfa 01), two rates (200 and 400 kg ha?1 K2O) and with no K fertilization (control). Potassium chloride was used as the standard to which the other sources of potassium were compared. Two consecutive crops of millet were grown in the same pots. The first crop received potassium source application but not the second. At the end of experiment, shoot dry matter production, shoot potassium concentration, shoot accumulated potassium, soil potassium and relative agronomic efficiency were determined. The relative agronomic efficiency, calculated from crops, was 100% for KCl, was 84% for Alfa 02 and was 11% for Alfa 01. In the shoot dry matter production and accumulated potassium only Alfa 01 was not statistically different of control. Millet absorbed potassium from the Alfa 02 source in both the first and second crops. 相似文献
72.
73.
S. H. Begna D. L. Smith R. I. Hamilton L. M. Dwyer & D. W. Stewart 《Journal of Agronomy and Crop Science》2001,186(4):267-271
Identifying corn ( Zea mays L.) genotypes with faster rates of seedling emergence and leaf appearance is important in developing a corn crop with earlier canopy closure and better seasonal light interception. A greenhouse experiment was conducted twice to investigate whether corn genotypes known to vary in canopy architecture and yield potential differed in rates of seedling emergence and leaf appearance. The experiment was arranged in a randomized complete block design utilizing seven genotypes: five of the newly developed Leafy reduced-stature (LRS) types (LRS1, LRS2, LRS3, LRS4 and LRS5), one conventional type [Pioneer 3979 (P3979)], and one late-maturing big-leaf (LMBL) type. Five seeds were planted in each pot and seedling emergence was recorded every day until all seeds emerged. Leaf appearance was recorded from seedling emergence until the plants reached anthesis. There was variability among the genotypes for both seedling emergence and leaf appearance rate. Mean seedling emergence values of greater than 90 % were achieved by four of the five LRS genotypes, and the LRS types generally emerged more rapidly than the others. Leaf appearance rate showed linear increases over time; however, LRS genotypes (in particular LRS3, LRS4 and LRS5) had more rapid leaf appearance rates than the others. The LMBL hybrid ranked last for both seedling emergence (<80 %) and leaf appearance rate. Rapid seedling emergence and leaf appearance by early-maturing genotypes (LRS and P3979, especially LRS) may help these types of genotypes achieve earlier canopy closure and better use of the light available during the growing season, which is critical in a short growing season environment. 相似文献
74.
Slipped capital femoral epiphysis in calves 总被引:2,自引:0,他引:2
G F Hamilton A S Turner J G Ferguson J W Pharr 《Journal of the American Veterinary Medical Association》1978,172(11):1318-1322
75.
76.
Post mortem examination of red deer calves on a deer farm situated on hill ground in north-east Scotland revealed infection by a lungworm morphologically similar to Dictyocaulus viviparus. Trials were conducted to monitor the natural development of D viviparus infection in red deer, to investigate the value of a commercial lungworm vaccine and to evaluate methods of treating clinical cases. The findings indicate that the syndrome may be less apparent in red deer than it is in cattle, protection might be gained by vaccination and that housing and medication provide useful therapy. The extent of clinical disease is likely to depend on the general health, bodily condition and nutritional status of the animals versus the weight of infection acquired from the pasture. However, various factors can affect both sides in this confrontation. 相似文献
77.
A chlorine dioxide-containing gel was compared with 3 commercially available antimicrobials and 1 antibiotic intended for topical use. This gel was tested at 0.5 X and 4 X and was found to be more effective as a 4 X gel in treating Pseudomonas aeruginosa-infected excised wounds on mice. To further compare this gel with other antiseptics, a murine bioassay was developed. This wound model consisted of an excised cutaneous wound on the dorsum of mice which were irradiated (800 rad) and inoculated with P aeruginosa at 10-fold dilutions, from 10(-2) to 10(-10). The wounds were observed for latency of infection or mice survival time as a function of concentration of viable organisms remaining after treatment. The advantage of this model was demonstrated where a standard curve based on latency did not consume as many test subjects and yet provided an estimate of viable organisms in each wound. In this model, the chlorine dioxide-containing gel was more active than were preparations of providone-iodine, chlorhexidene, or silver sulfadiazine and was similar to polymyxin-bacitracin-neomycin ointment as a topical antiseptic. The effectiveness of the tested gel was reduced if delays in treatment were longer than 1 hour. 相似文献
78.
Semi-hardwood cuttings of Cotoneaster divaricata grown in 926 cm3-containers were top-dressed with controlled-release Osmocote (18.0 N-2.6 P-10.0 K) at levels of 0, 2, 3 or 6 g/l of container. Optimum shoot and root growth was obtained at 2 g/l. Applications of controlled-release fertilizer significantly increased foliar N and P concentration, but not foliar K. The most desirable shoot-to-root ratio occurred at 2 g/l. 相似文献
79.
Toxoplasmosis in two horses 总被引:3,自引:0,他引:3
80.