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21.
Detailed chemical studies and RAPD analysis were done in different populations of Podophyllum hexandrum collected from high altitude regions of North Western Himalayas. Random amplified polymorphic DNA (RAPD) analysis revealed a high degree of genetic diversity among the 12 collected accessions, attributed to their geographical and climatic conditions. HPLC analysis also revealed variation in the concentration of two major marker compounds which lead to the identification of a chemotype. The study demonstrated that RAPD and chemical markers are very useful tools to compare the genetic relationship and pattern of variation among such prioritized and endangered medicinal plants.  相似文献   
22.
Hybrid rice (Oryza sativa L.) has been proven to be effective in increasing yield potential, but lodging often limits its yield in high-yielding environments. This study was conducted to determine genotypic variation in lodging resistance and lodging-related morphological traits among hybrid and non-hybrid check varieties, and to identify the key morphological traits associated with lodging resistance. Lodging behavior of 16 rice genotypes, including 12 hybrids and four inbreds, was studied at the International Rice Research Institute farm during the 2004 wet season (WS) and 2005 dry season (DS). Grain yield and visual score of lodging were determined at maturity. Lodging-related morphological traits were measured at 30 days after flowering. Large genotypic differences in lodging-related morphological traits were observed. Among these traits, dry weight per unit length, breaking resistance, and lodging index (bending moment/breaking resistance × 100) of lower internodes were significantly correlated with visual score of lodging. Several hybrids demonstrated high lodging resistance although their average plant height was over 120 cm. The lodging-related morphological traits and visual score of lodging in these hybrids were comparable with those of the non-hybrid check varieties with strong lodging resistance. These results suggest that increases in dry weight per unit length and breaking resistance of lower internodes are primary targets for reducing lodging index, thus improving overall lodging resistance of hybrid rice in a breeding program.  相似文献   
23.
Journal of Crop Science and Biotechnology - Understanding genetic architecture of a crop germplasm is necessary for designing a successful breeding program. Herein, we evaluated a large collection...  相似文献   
24.
Marine environment has been identified as a huge reservoir of novel biometabolites that are beneficial for medical treatments, as well as improving human health and well-being. Sponges have been highlighted as one of the most interesting phyla as new metabolites producers. Dactylospongia elegans Thiele (Thorectidae) is a wealth pool of various classes of sesquiterpenes, including hydroquinones, quinones, and tetronic acid derivatives. These metabolites possessed a wide array of potent bioactivities such as antitumor, cytotoxicity, antibacterial, and anti-inflammatory. In the current work, the reported metabolites from D. elegans have been reviewed, including their bioactivities, biosynthesis, and synthesis, as well as the structural-activity relationship studies. Reviewing the reported studies revealed that these metabolites could contribute to new drug discovery, however, further mechanistic and in vivo studies of these metabolites are needed.  相似文献   
25.
This study was conducted to replace soya bean meal with maggot meal at difference percentages. A total of 120 one‐day‐old broiler chicks were divided into four groups. Four diets were formulated with maggot meal to replace soya bean meal at the rate of 0%, 10%, 20% and 30% designated as A, B, C and D respectively. Feed and water were offered ad libitum during the study which lasted for 28 days. Feed intake decreased significantly in treated groups while body weight, Feed conversion ratio and dressing percentage increased significantly in group D. Apparent metabolizable energy increased significantly in the group fed 30% maggot meal; however, no significant difference was found in dry matter, crude protein, crude fibre, ether extract, ash and nitrogen free extract between the control and treated groups. The result of sensory evaluation revealed that tenderness and juiciness increased significantly in group C and B respectively. The colour and flavour were most accepted in group B and C. The results indicate that replacement of soya bean meal at the rate of 30% in broiler feed produced most favourable results.  相似文献   
26.
27.
Lumpy skin disease (LSD) is a highly infectious disease of cattle caused by a virus belonging to the Capripoxvirus genus of the family Poxviridae. The purpose of this study is to place on record the first confirmation of LSD in the Sultanate. The disease was diagnosed and confirmed using polymerase chain reaction, histopathology, transmission electron microscopy and serum neutralization testing. The epizootic occurred in 2009 involving a large number of animals and covering a wide area including Nezwa, Alqabel, Sohar, Saham and Burimi. Morbidity and mortality rates of 29.7 and 26.3 %, and 13.6 and 15.4 % were observed at Nezwa and Sohar, respectively. The clinical signs were much more severe in Holstein–Friesian cattle compared to indigenous breeds and were characterized by multiple skin nodules covering the neck, back, perineum, tail, limbs and genital organs. Affected animals also exhibited lameness, emaciation and cessation of milk production. Oedema of limbs and brisket, and superficial lymph node enlargement were highly prominent. It is not known from where the virus originated, or how it spread to the Sultanate. The disease has become endemic in the country and is liable to extend to other Gulf Cooperation Council Countries and cause a pandemic. It is of major concern to the Omani dairy industry. Due to the widespread presence of screw worm, serious economic losses can follow outbreaks.  相似文献   
28.
To assess the drainable surplus of an irrigated area, a methodologybased on a groundwater-balance approach was developed and appliedin Schedule I-B of the Fourth Drainage Project near Faisalabad inPakistan. To determine the seasonal net recharge in this area, anumerical groundwater model was run in inverse mode. The data inputfor the model consisted of the geometry of the aquifer system, theaquifer parameters, and historical watertable elevations. The seasonalnet recharge values, calculated from the individual recharge anddischarge components, were tuned with the results of the inversemodelling. The advantage of such an integrated approach is that allthese components are linked. The design net recharge was estimatedfrom the historical net recharge of the wettest monsoon in the studyperiod. Its rainfall recharge values were then substituted for those of adesign monsoon. In this substitution procedure, the rainfall rechargemethodology and parameters were adopted from the tuning procedure.From this design net recharge, estimates could be made of the requireddrainable surplus, with and without drainage simulation.  相似文献   
29.

Rodents are sources of many zoonotic pathogens that are of public health concern. This study investigated bacterial pathogens and assessed their antimicrobial resistance (AMR) patterns in commensal rodents in Qatar. A total of 148 rodents were captured between August 2019 and February 2020, and blood, ectoparasites, and visceral samples were collected. Gram-negative bacteria were isolated from the intestines, and blood plasma samples were used to detect antibodies against Brucella spp., Chlamydophila abortus, and Coxiella burnetii. PCR assays were performed to detect C. burnetii, Leptospira spp., Rickettsia spp., and Yersinia pestis in rodent tissues and ectoparasite samples. Antimicrobial resistance by the isolated intestinal bacteria was performed using an automated VITEK analyzer. A total of 13 bacterial species were isolated from the intestine samples, namely Acinetobacter baumannii, Aeromonas salmonicida, Citrobacter freundii, Citrobacter koseri, Enterobacter aerogenes, Enterobacter cloacae, Escherichia coli, Hafnia alvei, Klebsiella pneumoniae, Providencia stuartii, Proteus mirabilis, Pseudomonas aeruginosa, and Salmonella enterica. The majority of them were E. coli (54.63%), followed by P. mirabilis (17.59%) and K. pneumoniae (8.33%). Most of the pathogens were isolated from rodents obtained from livestock farms (50.46%), followed by agricultural farms (26.61%) and other sources (22.94%). No antibodies (0/148) were detected against Brucella spp., C. abortus, or C. burnetii. In addition, 31.58% (6/19) of the flea pools and one (1/1) mite pool was positive for Rickettsia spp., and no sample was positive for C. burnetii, Leptospira spp., and Y. pestis by PCR. A total of 43 (38%) bacterial isolates were identified as multidrug resistant (MDR), whereas A. salmonicida (n?=?1) did not show resistance to any tested antimicrobials. Over 50% of bacterial MDR isolates were resistant to ampicillin, cefalotin, doxycycline, nitrofurantoin, and tetracycline. The presence of MDR pathogens was not correlated with rodent species or the location of rodent trapping. Seven (11.86%) E. coli and 2 (22.2%) K. pneumoniae were extended-spectrum beta-lactamases (ESBL) producers. These findings suggest that rodents can be a source of opportunistic bacteria for human and animal transmission in Qatar. Further studies are needed for the molecular characterization of the identified bacteria in this study.

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30.
A study was undertaken to evaluate the nutritional response of organically grown diets in buffaloes on nutrients utilization and nutrient efficiency for milk production. For this, ten milch Murrah buffaloes of average body weight (490.72?±?6.65 kg), milk yield (8.13?±?0.33 kg), and lactation stage (85?±?5.28 days) were distributed in inorganic (InDg) and organic dietary groups (OrDg) with five animals in each. Buffaloes of InDg and OgDg were fed sorghum hay–berseem fodder-concentrate mixture-based diets grown inorganically and organically, respectively. After 60 days of feeding, a digestion cum metabolism trial was conducted to assess feed intake, nutrient utilization, and N balance, while milk yield and composition were recorded fortnightly. DM, CP, digestible crude protein (DCP), and metabolizable energy (ME) intake (g/Kg w0.75) were similar in animals of InDg and OrDg. NDF, ADF, and hemicellulose digestibility were (P?<?0.05) higher in animals on OrDg (59.20, 51.55, and 62.67) than InDg diet (54.57, 43.72, and 56.61 %), respectively. Urinary n loss (g/day) was (P?<?0.05) lower in OrDg (67.23) than in InDg (83.55); however, milk N was comparable in animals of both dietary groups (47.36 vs 45.82 g/day). Nitrogen balance was higher in animals of OrDg (39.72) than in InDg (28.08). DCP, TDN, and ME values of both diets were similar. No effect of diet was observed on milk yield and its composition; however, increased lactation length decreased milk yield. Buffaloes on both diets had similar efficiency and conversion ratio of nutrients for milk production. Results revealed that diets (organically vs. inorganically grown) have no effect on milk yield and its composition; however, buffaloes on organic diet have higher fiber digestibility and low urinary N loss which did not affect the dietary nutrients efficiency and conversion ratio for milk production.  相似文献   
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