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911.
Several genotypes, number given within parenthesis, of chickpea, pigeonpea, urd bean, mung bean and soybean, differing in seed characteristics were analyzed for phytic acid, in vitro protein digestibility (IVPD), protein, total phosphorus, and seed size. Phytic acid contents and IVPD values differed significantly among and within these species. Phytic acid content (mg/g) was the highest in soybean (36.4) followed by urd bean (13.7), pigeonpea (12.7), mung bean (12.0) chickpea (9.6). On an average, phytic acid constituted 78.2 percent of the total phosphorus content and this percentage figure was the highest in soybean and the lowest in mung bean. In vitro protein digestibility (IVPD) of pigeonpea and chickpea genotypes varied from 60.4 to 74.4 percent and 65.3 to 79.4 percent, respectively. The IVPD values of genotypes of mung bean, urd bean and soybean ranged from 67.2 to 72.2 percent, 55.7 to 63.3 percent and 62.7 to 71.6 percent, respectively. There was a significant negative correlation between phytic acid and IVPD of these genotypes. Phytic acid was significantly and positively correlated with protein but the magnitude of correlation was very low in chickpea and pigeonpea. Results indicate that the genotypes of pulses with low phytic acid content could be identified and used in breeding program to improve their nutritive value and utilization.  相似文献   
912.
Soil bulk density (BD) and effective cation exchange capacity (ECEC) are among the most important soil properties required for crop growth and environmental management. This study aimed to explore the combination of soil and environmental data in developing pedotransfer functions (PTFs) for BD and ECEC. Multiple linear regression (MLR) and random forest model (RFM) were employed in developing PTFs using three different data sets: soil data (PTF‐1), environmental data (PTF‐2) and the combination of soil and environmental data (PTF‐3). In developing the PTFs, three depth increments were also considered: all depth, topsoil (<0.40 m) and subsoil (>0.40 m). Results showed that PTF‐3 (R2; 0.29–0.69) outperformed both PTF‐1 (R2; 0.11–0.18) and PTF‐2 (R2; 0.22–0.59) in BD estimation. However, for ECEC estimation, PTF‐3 (R2; 0.61–0.86) performed comparably as PTF‐1 (R2; 0.58–0.76) with both PTFs out‐performing PTF‐2 (R2; 0.30–0.71). Also, grouping of data into different soil depth increments improves the estimation of BD with PTFs (especially PTF‐2 and PTF‐3) performing better at subsoils than topsoils. Generally, the most important predictors of BD are sand, silt, elevation, rainfall, temperature for estimation at topsoil while EVI, elevation, temperature and clay are the most important BD predictors in the subsoil. Also, clay, sand, pH, rainfall and SOC are the most important predictors of ECEC in the topsoil while pH, sand, clay, temperature and rainfall are the most important predictors of ECEC in the subsoil. Findings are important for overcoming the challenges of building national soil databases for large‐scale modelling in most data‐sparse countries, especially in the sub‐Saharan Africa (SSA).  相似文献   
913.
Thermographic assessment of scab disease on apple leaves   总被引:1,自引:0,他引:1  
Phytopathogenic fungi may affect both the cuticular and the stomatal conductance of plant tissue resulting in significant modifications of leaf temperature. Venturia inaequalis colonizes apple leaves below the cuticle (subcuticularly) causing scab disease. The suitability of digital infrared thermography for sensing and quantifying apple scab was assessed by investigating the effects of V. inaequalis on the water balance of apple leaves in relation to the disease stage and the severity of scab. Transpiration was measured by infrared thermo-imaging to evaluate spatial heterogeneity of the leaves in response to localized infections. Fungal development was assessed microscopically. Subcuticular growth of the pathogen caused localized decreases in leaf temperature before symptoms appeared that significantly increased the maximum temperature difference (MTD) of leaves. The MTD increased with scab development and was strongly correlated to the size of infection sites (r2linear = 0.85) and overall disease severity (% diseased leaf area, r2square = 0.71). In later stages of the disease, the MTD decreased because of leaf senescence. Thermographic measurements revealed differences in disease severity resulting from disease stage, resistance of host tissue and differences in the aggressiveness of V. inaequalis isolates. Subcuticular growth of the pathogen was beyond the area of conidia production, therefore, the area of leaf with increased transpiration was larger than the scab lesions; the proportion decreased from >70% in the early stages to <20% for mature lesions. Leaf transpiration was increased by all stages of scab development, therefore, MTD may be used not only for the differentiation between diseased and non-diseased leaves, but also for disease quantification, e.g. in screening systems and monitoring in precision agriculture.  相似文献   
914.
To facilitate weed suppression, oilseed rape or canola (Brassica napus) has been genetically modified (GM) over the last two decades to incorporate herbicide tolerance (HT). The introduction of oilseed rape in commercial agriculture raises concerns about potential adverse agronomic and environmental effects linked to both the genetic modification and altered agricultural practice. How will this new crop modify the existing cropping practice? What are the potential agro-environmental implications of its introduction? This paper analyses and schematises recorded and conceivable agricultural practice changes with GMHT oilseed rape introduction and its likely agro-environmental effects. It develops a conceptual systematics of influencing factors, subsequent practice changes and likely agro-environmental effects. The results can be used to design the mandatory monitoring of adverse GM crop effects.  相似文献   
915.
Ion-selective electrodes have recently been designed for determining the ionized concentration of magnesium (Mg2+) in serum. This development may allow new insights into some metabolic diseases of cattle. For this report, the concentrations of Mg2+, total magnesium (Mgtot), ionized calcium (Ca2+), total calcium (Catot), and inorganic phosphate (Pi) were determined in sera from seventeen 3-to 16-year-old Brown Swiss and crossed Simmental/Red Holstein cows during the periparturient period. In each animal, a transient increase of Mg2+ and Mgtot serum concentrations was observed in association with the transient decrease in serum concentrations of Ca2+, Catot and Pi after parturition. On average, throughout the study, the serum Mg2+ concentrations were 68.5% of those of Mgtot, whereas the serum Ca2+ concentrations were 52% of those of Catot. The possible mechanisms involved in the transient increase of Mg2+ and Mgtot serum concentrations are discussed.Abbreviations Ca2+ ionized calcium - Catot total calcium - Mg2+ ionized magnesium - Mgtot total magnesium - Pi inorganic phosphate - PTH parathyroid hormone - PTHrP parathyroid homrone related protein  相似文献   
916.
917.
Two strains of E. coli O139:K12 (B):H1 were compared in vitro and in the intestinal environment. Both strains colonized the small intestines of experimentally inoculated pigs and exhibited in vivo a similar relationship to the microvillus border as enterotoxigenic E. coli (ETEC). Strain 107/86 grown on blood agar expressed numerous long flexible non-haemagglutinating fimbriae which were antigenically distinct from the known fimbriae of porcine ETEC. It adhered in vitro to porcine enterocyte brush border fragments. Strain 124/76 grown on blood agar was devoid of fimbriae and did not adhere to brush border fragments. However, fimbriae morphologically and antigenically indistinguishable from those of strain 107/86 were detected in the intestinal environment by direct immunofluorescence and by immuno electron microscopy.  相似文献   
918.
919.
Response surface(RSM)methodology based on a three-level three-factor Box-Behnken design of experiment was used to optimize the exopolysaccharide content(EPC)and the mycelium biomass in submerged cultivation by Clitocybe sp. AS 5.112. The critical factors selected for the investigation were cultivation temperature,time and volume of medium,based on the results of previous Plackett-Burman design. By analyzing the response surface plots,the optimum ranges of cultivation temperature,time and medium volume for obtaining over 1 253.00μgmL-1 of EPC lie in 24.3-25.8℃,9.7- 10.2d and 76.0-90.0 mL,respectively. While for obtaining over 8.32 mg mL-1 of dry cell weight(DCW),the above variables would be in the range of 23.8- 24.8℃,9.6- 10.3 d and 71.0 - 98.0mL,respectively. By solving the inverse matrix from the quadratic regression equations,the optimal conditions to gain 1 265.45μgmL-1 of EPC were 25.0℃,9.9d and 83.4mL,to gain8.50mg mL-1 of DCW were 24.4℃,9.9d and 87.1mL. In order to obtain the maximum yield of EPC and DCW at the same time,the above conditions would be 24.5℃,9.9d and 84.7mL,respectively,in this situation,the maximum predicted EPC and DCW were 1 261.60μgmL-1and 8.47 mg mL-1,respectively.. The experimental data under various conditions have validated the theoretical values.  相似文献   
920.
A juvenile male mixed breed dog was presented for lethargy, exercise intolerance, and aggression when touched on the head. Cyanosis, tachycardia, and tachypnea were observed and persisted during oxygen supplementation. Arterial blood gas analysis by co‐oximetry identified an increased methemoglobin concentration (27%; normal, <2%) with normal arterial oxygen tension. The methemoglobinemia and associated clinical signs resolved after administration of methylene blue (1 mg/kg) IV, and the dog was discharged. The affected dog's whole‐genome sequence contained 2 potentially causal heterozygous CYB5R3 missense mutations suggesting that cytochrome b5 reductase deficiency was responsible for the methemoglobinemia. This hypothesis was confirmed by enzyme analysis that identified cytochrome b5 reductase activity in the affected dog's erythrocytes to only approximately 6% of that in a control sample. Clinical signs recurred 11 days after discharge but normalized and the methemoglobin concentration decreased with methylene blue administration PO (1.5 mg/kg, initially daily and then every other day).  相似文献   
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