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101.
Muhammad Abdullah Jia Li Sidra Ghazanfar Jaleel Ahmed Imran Khan Mazhir Nadeem Ishaq 《东北农业大学学报(英文版)》2015,(2):80-86
Under the umbrella of WTO, the reduction in trade barriers has forced the policy makers to focus on the export competitiveness. Rice is an important source for foreign exchange earnings for the economy of Pakistan, keeping in mind of this fact, the competitiveness of Pakistan’s rice with other major exporters was examined by applying revealed competitive advantage. The domestic consumption trends of rice among the major rice exporting countries were also analyzed in the current study. The results revealed that as compare to other major exporters of rice in the world, Pakistan had high competitive and comparative advantage in the production of rice. The comparison of the movements in comparative advantage indices for Pakistan with the major world rice competitors/exporters showed that Pakistan possessed relatively high comparative and competitive advantages in rice production. The declining domestic per capita consumption of rice and increasing trends in competitiveness for Pakistan clearly revealed the expected potential of higher growth which meant that rice exports from Pakistan could continue to play an important role for the earnings of foreign exchange. In order to exploit the potential benefits of rice exports, we need to strengthen the competitiveness in rice sector of Pakistan. 相似文献
102.
Systemic control of cattle grubs (Hypoderma spp.) in steers treated with Warbex and weight gains associated with grub control. 总被引:1,自引:1,他引:0
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When applied to yearling steers on November 30, pour-on applications of famphur at 40 or 50 mg/kg were unsatisfactory for systemic grub control as they only reduced the number of warble grubs by 52.2 and 68.4%, respectively. The treatments, which had no adverse effects on the health of steers or cellular constituents of their blood, reduced the whole-blood cholinesterase, with the maximum reduction occurring 15 days after treatment. Low ambient temperatures prevailing at the time of treatment and during the two following weeks might have impeded the absorption of famphur through the skin and reduced its effectiveness for grub control. With the grub damage kept to the minimum by weekly manual removal of warble grubs, the groups treated with famphur at 40 or 50 mg/kg outgained (P less than 0.05) the untreated group by 29.9 and 13.4 kg/steer, respectively, during the posttreatment period of 181 days. These results indicate the economic benefits of grub control. 相似文献
103.
A commercially available inactivated Mycoplasma gallisepticum (MG) bacterin was administered to chickens on a multiple-age farm endemically infected with MG. A total of 3400 MG-free pullets were vaccinated with the MG bacterin at 19 weeks of age, and 4300 unvaccinated pullets served as controls. The vaccinated group became serologically positive by the rapid plate agglutination (RPA) test within 3 weeks, and the unvaccinated group became positive in 7 weeks. The hemagglutination-inhibition test responses were observed at approximately the same time as the RPA in both of the groups. Egg production and mortality through 50 weeks of age did not differ significantly between the two groups. MG was isolated from birds of the vaccinated and control groups near the termination of the study. 相似文献
104.
105.
M. M. A. Khan Samiullah S. H. Afaq R. M. Afridi 《Journal of Agronomy and Crop Science》1995,174(2):91-98
A pot experiment was conducted on Black nightshade ( Solanum nigrum L.) to study the effect of urea nitrogen and select the optimum dose required for its vegetative and reproductive growth, leaf NPK content, yield of fruit and fruit solasodine. Urea was applied at 0.0, 0.45, 0.90, 1.35, 1.80 and 2.25 g N per pot which contained 3.5 kg soil. Seeds were sown directly in pots and plant samples were drawn at fortnightly intervals for recording growth and yield parameters. In addition, solasodine content in fruit and N, P and K in leaves were also estimated. The results showed that all the parameters were influenced by N. In general, N at 1.80 g per pot was optimal. 相似文献
106.
1. Dwarf egg layer (Narmada XL) dwarf broiler (DB) and normal bodied sib (NB) hens were studied under cyclic summer hot and dry heat stress of 21.1 to 45.5 degrees C for a period of 50 d. The genotype effect for egg production was significant (P less than 0.01). 2. N-XL and DB genotypes laid 12.1% more eggs than NB. Egg production declined by 3.17, 1.27 and 3.25% for a rise in temperature (maximum) of 1 degree C for N-XL, DB and NB genotypes respectively. 3. Egg production in Narmada XL declined by 42% compared to 25% in the dwarf broilers. The regression coefficients differed significantly. 4. For polygenically identical DB and NB broiler breeder hens the heat stressor significantly reduced egg production 1.98% more in the NB genotype compared with DB with a 1 degree C rise in temperature. 5. Mortality was less in the N-XL as compared to DB, but NB hens showed 11.7% more mortality than dwarfs. 相似文献
107.
108.
Lateral spread of S6 strain Mycoplasma gallisepticum (MG) was studied in small populations of chickens. One experimentally exposed bird served as the source of infection, and the presence of MG-agglutinating antibody was evidence of infection in individuals. The results were subjected to survival data analysis. In the seven experiments, four similar but not identical phases of lateral spread were observed: phase 1, a generally long latent phase (median 15, range 12-21 days) before antibody was first detected in the MG-inoculated bird; phase 2, a generally short period (median 1, range 1-21 days) in which infection gradually appeared in 5-10% of the population; phase 3, a fairly constant characteristic phase (median 24, range 7-32 days) in which 90-95% of the remaining population developed MG antibody; phase 4, a generally short terminal phase (median 4, range 3-19 days) in which the remainder of the population became positive. Increasing the population density increased the rate at which lateral spread occurred. 相似文献
109.
A. R. Khan 《Journal of Agronomy and Crop Science》1988,161(4):234-237
A simple approach was undertaken to estimating bare soil evaporation in a soil column in a laboratory. The measurement of soil heat flux and soil water flux at various depths provides a practical means of assessing and evaluating the position of the drying front (evaporation zone) in the soil. 相似文献
110.