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21.
Irrigation and Zn fertilizer management improves Zn phyto‐availability in various rice production systems
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Hafeez ur Rehman Faiz Rasool Masood Iqbal Awan Athar Mahmood Abdul Wakeel Roghieh Hajiboland 《植物养料与土壤学杂志》2018,181(3):374-381
Zinc (Zn) is an important micronutrient for rice (Oryza sativa L.) production and its deficiency has been observed in various production systems. High grain Zn concentration is equally important for high rice yield and human health. In this work, the effects of Zn fertilization on seedling growth, grain yield, grain Zn concentration, and their association with root traits were studied under alternate wetting and drying (AWD), aerobic rice (AR), system of rice intensification (SRI), and continuous flooding (CF). Zinc fertilization (15 kg ha?1) improved nursery seedlings chlorophyll and Zn concentrations, root length, and number of roots with highest values observed in CF. At harvesting, maximum plant height, panicle length, total and panicle bearing tillers, and kernel yield were found with Zn addition in AWD and CF rice systems. Mid season drainage provided at maximum tillering and Zn fertilization increased its concentration in leaves, culms, panicles, and grains under CF and AR at physiological maturity. Most of Zn applied was allocated into culms and panicles, nevertheless, a significant increase in grain Zn concentration was also observed in all production systems. Association of leaf Zn with grain Zn concentration was stronger than with culm and panicle Zn. The results indicate that Zn application after rice nursery transplanting is more important for grain Zn enrichment in all rice systems than for increase in grain yield in all systems except AWD where grain yield was also increased. More grain yield in CF and AWD as compared to SRI and AR can also be attributed to decreased spikelet sterility and to better Zn phyto‐availability in these rice systems at physiological maturity. 相似文献
22.
Intazar Ali Zhang Shuai Asif Sajjad Hafiz Mahmood ur Rehman Cui Jin-Jie 《Phytoparasitica》2018,46(1):127-135
The green lacewing Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae) is a common and abundant predator in many cropping systems in palearctic realm and it’s conservation is helpful in sustainable pest management in agro-ecosystem. Prior to commercialization of Bt crops in any agro- ecosystem, it is necessary to evaluate the impact of Cry proteins upon non-target organisms especially biological control agents (BCA). In present study an artificial diet consisting of shrimp, beef, beef liver and egg yolk was developed to mass-rear C. pallens for its use as biological control agents in sustainable pest management. Moreover, an artificial diet based risk assessment protocol was developed to investigate the impact of Cry1Ac, Cry1Fa and Cry2Ab on the survival and reproductive performance of C. pallens adults. C. pallens was fed on diets incorporated with Cry proteins and without addition of Cry proteins (control). The same diet containing boric acid was served as a positive control. Temporal stability, bioactivity and intake of Cry proteins by C. pallens were confirmed using double-antibody sandwich, enzyme-linked immunosorbent assay and bioactivity verification bioassays. Survival and reproductive performance of C. pallens, e.g., pre-oviposition period, daily fecundity, total fecundity and 30-day old adults dry weights, exhibited non-significant differences (p?>?0.05) for the diets containing Cry1Ac, Cry1Fa and Cry2Ab (50 μg/g) against Control. However, significant reduction in survival and reproductive performance (p?<?0.05) was observed in positive control. Our findings reveal that artificial diet is a good source of nutritional requirement with enhanced survival and reproductive performance of C. pallens and can be used for mass rearing of predator in case of natural diet scarcity and Cry proteins are safe for adult C. pallens and Bt crops cultivation help in predators conservation in sustainable agriculture. 相似文献
23.
Noureen Arshad Khalid Mahmood Zia Farukh Jabeen Muhammad Naveed Anjum Nadia Akram Muhammad Kaleem Khosa 《Fibers and Polymers》2018,19(11):2219-2228
The research work was carried out to synthesize a series of novel chitosan based water dispersible polyurethanes (CS-WDPUs). The three step synthesis involves the formation of end capped PU-prepolymer was formed through the reaction between polyethylene glycol (PEG) (Mn=600 g/mole, dimethylolpropionic acid (DMPA) and isophorone diisocyanate (IPDI) followed by the preparation of neutralized NCO terminated PU-prepolymer, which lead to the chain extension by using the chitosan. The dispersion of the obtained product was carried out by adding proper proportion of water. The synthesized CS-WDPUs were applied onto the different qualities of plain weave poly-cotton printed and dyed textile swatches by employing pad-dry-cure procedures. The textile assets of the treated and untreated textile swatches were assessed, as color fastness, pilling resistance, tear and tensile strength. The results showed that the chitosan incorporation into PU backbone has significant effect on the assets of treated textiles. These synthesized CS-WDPUs are eco-friendly bio-based finishes with potential applications for polyester/cotton textiles. 相似文献
24.
Naila Kaneez-e-Batool Faisal Mahmood Sabir Hussain Muhammad Riaz Zahid Maqbool 《Archives of Agronomy and Soil Science》2016,62(9):1285-1292
More than 50% of global soil organic carbon stocks are stored below 20 cm of soil depth capable of massively altering global C cycle and climate. However, subsoil C dynamics are largely overlooked implicitly assuming that surface and subsoil C dynamics are similar. Here, we compared the soil C dynamics in surface and subsurface soil layers in response to nitrogen and maize leaf litter additions. Soils, sampled from 0 to 5, 15 to 35, 35 to 55 and 55 to 75 cm depths, were incubated at 25°C after adding litter, nitrogen (NH4NO3) or litter plus nitrogen. Soil respiration (C mineralization) was measured throughout the incubation period. Litter addition significantly increased C mineralization in all the soil layers. However, the soil CO2 release relative to control was more than twofold higher in 15–35 and 35–55 cm soil layers than the surface layer. Nitrogen additions significantly decreased C mineralization in 0–15 cm soil, increased in 35–55 cm and had minimal effects in the 15–35 and 55–75 cm layers. Different soil C dynamics in surface and subsurface soil layers found in our study contradict the general assumption that soil C dynamics may be treated similarly along different soil depths. 相似文献
25.
Exogenous protease supplementation of poultry by‐product meal‐based diets for broilers: Effects on growth,carcass characteristics and nutrient digestibility
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T. Mahmood M. A. Mirza H. Nawaz M. Shahid 《Journal of animal physiology and animal nutrition》2018,102(1):e233-e241
An experiment was conducted to investigate the effects of three levels (0%, 3% and 6%) of poultry by‐product meal (PBM) with or without protease on broiler growth, carcass characteristics and nutrient digestibility from 1 to 35 days. Two hundred and forty birds (n = 240) were fed equi‐caloric and equi‐nitrogenous (ME 2850 kcal/kg; CP 20%) diets throughout the experiment. The enzyme supplementation increased feed intake (p < .01) and body weight gain (p < .01), but feed:gain remained unaffected (p > .05) from 1 to 21 days. Increasing level of PBM decreased feed intake (p < .05), but body weight gain was improved (p < .05) at 3% PBM level during 1 to 21 days. The feed:gain was improved (p < .05) in birds fed diets containing 3% PBM. The feed:gain was also improved in birds fed diets containing 3% PBM from 1 to 35 days. However, feed intake and body weight gain in birds fed diets containing PBM remained unaffected. An interaction (p < .01) on feed intake between enzyme and PBM was noticed during 1 to 21 days. However, no interaction was recorded for body weight gain and feed:gain. The per cent carcass yield improved (p < .01) in birds fed diets supplemented with enzyme. The per cent breast meat yield was depressed (p < .005) in birds fed diets containing PBM. Apparent metabolizable energy (p < .001), nitrogen retention (p < .01), apparent metabolizable energy corrected for nitrogen (p < .001), and apparent digestibility coefficient for nitrogen (p < .01) improved in birds fed diets containing enzyme; however, a reverse was noticed in those fed diets containing only PBM. In conclusion, inclusion of 3% PBM along with supplementation of exogenous protease improved performance and nutrient digestibility in broilers. 相似文献
26.
Ornithobacterium rhinotracheale is a gram negative bacterial pathogen causing respiratory tract infections in poultry. Tracheal, lung and serum samples were
obtained from 21 broiler flocks of 8 farms from a slaughterhouse located in south-eastern of Iran. Among 630 tracheal and
lung samples from samples resulting from 315 chickens, 11 (3.5%) ORT isolates were identified using biochemical tests. The
isolates originated from 9 (42.9%) flocks out of 4 farms. All of the isolates were recovered from tracheal swabs and showed
an API 20NE identification biocode 0-2-2-0-0-0-4. Of the 420 serum samples examined by ELISA, 134 (31.9%) sera from 17 (81.0%)
flocks were positive for ORT antibodies. These results indicate that ORT is present in most broiler flocks with respiratory
disorders in southeast Iran. 相似文献
27.
Fatemeh Rostami Mahmood Nafisi Bahabadi Farzad Salehi Hamidreza Nooryazdan 《Journal Of Applied Aquaculture》2013,25(4):309-321
ABSTRACTLitopenaeus vannamei postlarvae were exposed to 0, 6, 13, and 19 mg/L total ammonia nitrogen (TAN) treatments. After 45 days, shrimp weight and length were lowest under TAN concentrations of 13 and 19 mg/L (P ≤ 0.05). Maximum weight gain was observed in control and 6 mg/L treatments. Mortality was highest (80.55 ± 4.80%) under 19 mg/L reared in 35 ppt salinity. Average intermolt periods of PLs exposed to 0, 6, 13, and 19 mg/L TAN were 11.5 ± 0.7, 10.8 ± 1.3, 9.4 ± 1.0, and 8.7 ± 0.6 days under 35 ppt and 11.1 ± 0.5, 10.7 ± 0.6, 10.1 ± 0.5, and 9.5 ± 0.2 days under 45 ppt salinity. Although TAN increased postlarvae molting frequency, its negative effects on the shrimp growth and survival of PLs was directly linked to its concentration and exposure duration. Higher salinity reduces the effects of ammonia and increases the survival. 相似文献
28.
Ghulam Abbas Tariq Manzoor Khan Jehanzeb Farooq Abid Mahmood Rana Nadeem Abbas Wajad Nazeer Amjad Farooq Zuhair Hasnain Muhammad Naeem Akhtar 《Frontiers of Agriculture in China》2011,5(4):443-449
This research was conducted to explore genetic material that can yield better under salt stress conditions. The experiment
was laid out using 27 upland cotton genotypes in a RCBD 2 factorial arrangement with two replications. Saline water (NaCl
at 20 dS/m) was applied after satisfactory emergence was achieved. The crop was raised to maturity and data relating to yield,
fiber quality and ionic traits were recorded. Analysis of variance showed significant variations in the germplasm. Plant height,
bolls per plant, boll weight, GOT%, staple length, staple strength, K+ and K+/Na+ ratio under salinity stress showed a highly significant correlation with seed-cotton yield. The highest direct effect on
seedcotton yield per plant was exhibited by bolls per plant and boll weight. The results from the correlation and path coefficient
analyses revealed that although the K+/Na+ ratio had a strong positively significant association with seedcotton yield, its direct effect on the seed-cotton yield was
negative and thus selection on the basis of K+/Na+ may not be fruitful. Hence, only indirect selection through bolls per plant and boll weight may be effective in increasing
the seedcotton yield per plant under salinity stress. 相似文献
29.
Qudsia Nazir Muhammad Javed Akhtar Muhammad Imran Azhar Hussain Sajid Mahmood 《Journal of plant nutrition》2017,40(9):1339-1350
This study was conducted to evaluate the simultaneous use of plant growth promoting rhizobacterium (QS1) and different combinations of urea-nitrogen and biogas slurry-nitrogen for improving growth, yield, and nutritional quality of field grown okra. The isolate QS1 was identified as Bacillus sp. QS1 based on its ribosomal ribonucleic acid (rRNA) sequence analysis. Results revealed that among the combinations, the application of 50% urea-nitrogen + 50% biogas slurry-nitrogen was optimal for improving crop performance. This combination significantly (p ≤ 0.05) promoted okra growth viz. plant height (69.63–80.03 cm), no of branches per plant (14–18), shoot fresh weight (86.66–136.25 g/plant), root fresh weight (22.5–26.58 g/plant), and fruit yield (8.5–13.5 kg/plot) compared to the plants receiving 100% urea-nitrogen. The interactive effective of this nitrogen combination and QS1 inoculation produced the highest growth and yield response. Similarly, the same treatment improved nitrogen, phosphorus, potassium, and protein contents in shoot and fruit of okra compared to other treatments. 相似文献
30.
Rabbani H Ostadkarampour M Danesh Manesh AH Basiri A Jeddi-Tehrani M Forouzesh F 《Iranian Biomedical Journal》2010,14(3):77-82
Background: The ectopic expression of receptor tyrosine kinase Ror1 has been reported in patients with hematological malignancies such as chronic lymphocytic leukemia and acute lymphoblastic leukemia. Here we report, for the first time, expression of ROR1 gene in both tumor tissues and peripheral blood mononuclear cells (PBMC) from patients with renal cancer (RC). Methods: In the current study, the expression of ROR1 gene was semi-quantitatively measured in PBMC and tumor tissues from 16 RC patients as well as PBMC from 22 healthy individuals relative to the expression of the housekeeping gene phosphoglucomutase 1 by RT-PCR. Results: Our results showed that ROR1 was expressed at gene level in 81.3% of renal tumor tissues (13 out of 16) whereas it was expressed in 94% of PBMC from RC patients (15 out of 16). A weak expression of ROR1 was observed in PBMC of 4 out of 22 healthy individual. A significant expression of ROR1 was observed in PBMC from RC patients when compared to that in PBMC from normal healthy individuals (P<0.001). The expression of ROR1 in PBMC may reflect a shedding of tumor cells into blood stream. Conclusion: We conclude that detection of a high level of ROR1 expression in blood cells might assist in early detection of renal malignancies, providing taking into consideration the clinical symptoms of the disease. Key Words: ROR1, Ectopic expression, Renal cancer 相似文献