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991.
Munir Ahmad Dost Muhammad Maria Mussarat Abid Ali Khan Shah Faisal Khan Muhammad Waqas Javed 《Journal of Soils and Sediments》2017,17(4):936-948
Purpose
The main purpose of this research work was to assess soil nutrient, spatial variability, and their mapping through GIS for better fertilizer recommendation and management.Materials and methods
Soil samples (0–20-cm depth) were collected from major crop areas of district Chitral, northern Pakistan during April 2014. The crops areas were divided into eight main sampling units. Each sampling location was recorded through GPS point. The samples were then brought to laboratory of Soil and Environmental Sciences, for further analysis.Results and discussion
The overall results showed that Zn content was the most deficient nutrient followed by K with 86 and 64% of samples, respectively. These results are different from other plain and agricultural areas which are dominantly deficient in order of N > P > K that could be associated to steep topography, climatic condition, and parent materials. The analyzed nutrients varied independently as indicated by their lower correlation values but showed stronger spatial patterns. Gaussian, linear, and exponential models were used depending on mean prediction error (MPE), root mean square standardize prediction error (RMSSPE), and nugget values for semivariogram analysis and consequent mapping of different nutrients through GIS.Conclusions
The N and P were weakly distributed, while K and all micronutrients had strong spatial pattern suggesting that only N and P were managed during farming practices and that varied irregularly in the sampled area. In contrast to other plain agricultural areas of the country, the Zn and K were the most deficient elements and should be applied with suitable Zn and K fertilizers for optimum crop production in the area. This low Zn and K contents would be associated to the parent materials, low pH, and high organic matter contents especially in high altitude and comparatively high P content in the soil. The prepared maps can help on site-specific recommendation of fertilizers for farmers, researcher, and planners.992.
Results characterizing the fabric of soil aggregates are discussed. Experimental evidence and theoretical substantiation of
the fabric of soil aggregate are given. Soil aggregates are characterized by the tight packing of water-stable particles arranged
into certain layers. The curves of aggregate destruction follow the exponential law, which reflects the layered fabric of
the aggregates and the distribution of the ”nuclei” of waterstable aggregates in them. 相似文献
993.
Khan N Katsube-Tanaka T Iida S Yamaguchi T Nakano J Tsujimoto H 《Journal of agricultural and food chemistry》2008,56(13):4955-4961
To obtain fundamental information for nutritional improvement of rice (Oryza sativa) seed proteins, the alpha polypeptides of the major storage protein glutelin varied over the genus Oryza were qualitatively and quantitatively characterized with unique methods. The polypeptides were maximally separated by two-dimensional electrophoresis (2D-PAGE) composed of nonequilibrium pH gradient gel electrophoresis (NEPHGE) and higher temperature SDS-PAGE. Then the subunit for each polypeptide spot was identified with the sequential immunodetection called a step-by-step detection method, making use of highly subunit-specific antibodies. The comparative analysis showed considerable variation in the accumulation level of A-type and B-type glutelin subunits and found unknown glutelin subunits that were unable to be identified with the antibodies used. Wild species accumulating a high amount of lysine-rich B-type glutelin subunits and unknown unique subunits were identified as they might play a crucial role in nutritional quality improvement of the cultivated rice. 相似文献
994.
Bench scale kinetic experiments were conducted to examine the use of cell immobilization in calcium alginate to remove ammonia in anaerobic sludge digester supernatant. Two systems, immobilized nitrifiers and co-immobilized nitrifiers and denitrifiers, were studied with and without the addition of methanol. Results indicated that partial nitrification (to nitrite) was achieved in both systems. The co-immobilized reactors did not exhibit the extent of nitrite accumulation observed in the solely nitrifying reactors. The nitrifying reactors were unable to buffer the hydrogen ion production, during the nitrification process, to the level the co-immobilized cell reactors achieved. Both of these differences suggested the occurrence of denitrification in the co-immobilized reactors. Scanning electron microscopic images of bacteria immobilized in the alginate spherical beads support the results of the kinetic experiments. Nitrifiers colonized in the 100–200 μm peripheral layer of the beads. Large voids caused by nitrogen gas due to denitrification were found in a number of co-immobilized bead samples. 相似文献
995.
Haider Iqbal Khan 《水稻科学》2018,25(6):357-362
A field experiment was carried out to evaluate the feasibility of inoculating rice seedlings with biofertilizers (Azospirillum and Trichoderma) in order to reduce the use of chemical inorganic nitrogen (N) fertilizer on rice variety BU Dhan 1. The plant performances were better when 25% less inorganic N was applied with Trichoderma and combined application of Trichoderma and Azospirillum. Plants contained the highest chlorophyll concentrations when they were treated with 75% N + Trichoderma. Considering the yield attributes, 75% N + Trichoderma and 75% N + Trichoderma + Azospirillum performed similar to the control. The grain yield of rice was similar to the recommended dose even with 25% less N application. Application of Trichoderma resulted higher yield, followed by combined application with Azospirillum. Results revealed the greater scope of applying biofertilizer (Trichoderma) to supplement chemical N fertilizer with optimum yield of rice. 相似文献
996.
997.
Efficiency of utilisation of energy from maize- and broken rice-based diets in old White Leghorn and Rhode Island Red laying hens. 总被引:1,自引:0,他引:1
1. The efficiency of utilisation of metabolisable energy (ME) for maintenance (k(m)) from diets containing maize and broken rice (BR) at 500 g/kg was studied in old White Leghorn (WL) and Rhode Island Red (RIR) laying hens using the respiration calorimetry technique. The maize-based diet contained 180.8 g crude protein (CP)/kg and 16.4 MJ gross energy (GE)/kg while the BR-based diet contained 173.2 g CP/kg and 16.3 MJ GE/kg. Diets were fed for 10 d, while an energy and nitrogen metabolism study was conducted during 3 d on an ad libitum-fed diet followed by another 3 d on two-thirds of the ad libitum-fed quantity. 2. ME values for the maize- and BR-based diets for WL hens were 73.3% and 77.6% of the GE, whereas for the RIR hens these were 77.7% and 80.0%, respectively. 3. Fasting heat productions, determined at the end of 24 h fast for WL and RIR hens were 473.2 and 366.1 kJ/kg W0.75/d, respectively. During fasting WL and RIR hens utilised body energy reserves with efficiencies of 84.9% and 73.7%, respectively. 4. The k(m) of maize- and BR-based diets for the WL hens were 81.6% and 79.6%, whereas for the RIR hens these were 74.2% and 76.0%, respectively. 5. ME for maintenance of WL and RIR hens were 589 and 499.6 kJ/kg W0.75/d, respectively. 6. It is concluded that although WL and RIR hens differ significantly in energy metabolism, their efficiency of utilisation of energy from maize- and BR-based diets are similar. 相似文献
998.
Antigens from larvae of Hyalomma anatolicum anatolicum were extracted and purified by immunoaffinity chromatography using immunoglobulin ligands from cross-bred animals immunized with soluble larval antigen. Affinity-purified antigen (Aff-TLE) and a total larval extract (TLE) were used to immunize cross-bred (Bos indicus×Bos taurus) cattle. The group immunized with Aff-TLE rejected 71.6% of larvae and 77.3% of nymphs. However, the rejection percentages were lower in the TLE-immunized group. No significant changes in the feeding period, moulting percentages or moulting period of engorged larvae and nymphs were recorded. There was, however, a significant decrease in the number of resultant nymphs p<0.01) and adults (p<0.01) in the ticks fed on the Aff-TLE-immunized group. The Aff-TLE antigen was 93.3% purified. SDS-PAGE analysis identified a 39 kDa protein, reported for the first time, as the antigen responsible for the induction of resistance in the host. 相似文献
999.
Ascochyta blight of chickpea in Australia: identification, pathogenicity and mating type 总被引:4,自引:0,他引:4
The aetiology of blight of chickpea in South Australia was studied following sporadic disease outbreaks over several years that had been tentatively identified as Phoma blight. Nine fungal isolates from diseased chickpeas were tested for pathogenicity in the glasshouse, of which two caused symptoms resembling those of Ascochyta blight. The two aggressive isolates were identified as Ascochyta rabiei based on morphological characteristics of cultures and RAPD analysis. This was further confirmed by successful mating to international standard isolates, which showed that the two Australian isolates were MAT1-1. These isolates are accessioned as DAR 71767 and DAR 71768, New South Wales Agriculture, Australia. This is the first time that A. rabiei has been positively identified in commercial chickpeas in the southern hemisphere. The pathogen was found (in 1992) in only one of 59 seed samples harvested throughout Australia between 1992 and 1996 and tested using International Seed Testing Association methods. The teleomorph has not been found in Australia and results to date suggest that only one mating type is present. This suggests that quarantine restrictions on imported chickpea seed should be retained to prevent the introduction of the opposite mating type. 相似文献
1000.
Muhammad Ali Khan Noorul Amin Arsalan Khan Muhamamd Imtiaz Farmanullah Khan Imran Ahmad Asad Ali Badshah Islam 《Gesunde Pflanzen》2016,68(4):191-200
A green atmosphere and interaction with nature (plants and flowers) can considerably improve the human senses and sanity by decreasing the stress associated with anxiety, depression, neurotic impairment, and other psychologic symptoms. The current paper reports a therapeutic horticultural study’s findings regarding the effect of indoor foliage plants and flower arrangements on health prospects of surgical patients. Two surgical wards, ward A (with foliage plants and arranged flowers) and ward B (without foliage plants and flowers), were selected for the study. A total of 270 patients were randomly assigned to either ward to give 135 patients in each. Patients admitted to ward A had significantly more optimistic and promising health improvements than those in ward B. Provision of foliage plants and flower arrangements to the patients in ward A resulted in shorter postoperative stays, lower intake of analgesics, lower pain intensity, less stress fatigue, and improved vital signs (blood pressure, heart rate, respiration rate, body temperature) as compared to patients in ward B. Moreover, analyses showed that patients in ward A had a stronger psychologic frame of mind regarding their recovery from surgery and had more positive emotions and feelings regarding their stay in the hospital. They also felt that the ward atmosphere was more calming, pleasant, and satisfactory. Additionally, small group discussions and focal interviews with ward doctors and nurses confirmed the findings of the questionnaire that foliage plants & flower arrangements create a cherished environment in the ward, reduce patients’ stress, improve medical and psychologic status of patients, and also conveye positive messages of the hospital. These findings confirm the therapeutic value of horticultural activities, particularly in surgical patients in a stressed hospital setting. 相似文献