De Novo Next Generation Sequencing of Plant Genomes     

Steve Rounsley  Pradeep Reddy Marri  Yeisoo Yu  Ruifeng He  Nick Sisneros  Jose Luis Goicoechea  So Jeong Lee  Angelina Angelova  Dave Kudrna  Meizhong Luo  Jason Affourtit  Brian Desany  James Knight  Faheem Niazi  Michael Egholm  Rod A. Wing 《Rice》2009,2(1):35-43

The genome sequencing of all major food and bioenergy crops is of critical importance in the race to improve crop production to meet the future food and energy security needs of the world. Next generation sequencing technologies have brought about great improvements in sequencing throughput and cost, but do not yet allow for de novo sequencing of large repetitive genomes as found in most crop plants. We present a strategy that combines cutting edge next generation sequencing with “old school” genomics resources and allows rapid cost-effective sequencing of plant genomes.  相似文献   

反相高效液相色谱法测定有机氯及含氮杀虫剂在水体·土壤沉积物及鱼体中的残留   总被引：6，自引：0，他引：6  

Shahid Mahboob  Ghazala  S. Sultana  Muhammad Rafique Asi  S. Nadeem  A.S. Chaudhry 《农业科学与技术》2009,10(5):9-12

[目的]测定水体、土壤沉积物以及鱼体内有机氯及含氮杀虫剂残留物,为科学评估杀虫剂残留对巴基斯坦地区公共卫生、农业和环境的影响提供依据。[方法]以食用鱼南亚野鲮为材料,设计2组体重,采用高效液相色谱法分别测定水体、土壤沉积物以及南亚野鲮体内α-硫丹、DDE、甲基对硫磷、异丙隆、呋喃丹、阿特拉津等含量。[结果]土壤沉积物中DDE的含量达（2．340±0．025）μg／g,在250～750g的南亚野鲮体内的含量分别为（0．270±0．0006）μg／g,但在水体中未发现DDE残留;不同饲料中农药残留物90％为有机磷、呋喃丹以及有机氯杀虫剂,6％为杀菌剂,仅4％为除草剂,在250～750g以及800～1300g的南亚野鲮体内硫丹的含量分别达到（0．491±0．0006）μg／g和（3．050±0．0608）μg/g,异丙隆的含量分别达到（0．010±0．0003）μg／g和（0．014±0．0006）μg／g,且随体重上升,其脂肪含量增加,积累的农药残留物则越多;硫丹、甲基对硫磷、阿特拉津和呋喃丹的含量在水体达到最大残留限量水平0．001μg／g。[结论]通过生物积累和在自然界中的运输以及再沉积作用,有机氯及其他杀虫剂的使用给全球的环境造成了严重污染,因此,在巴基斯坦已经禁止使用DDT等有机氯农药。  相似文献   

Vertical transmission and concurrent infection of multiple bacterial pathogens in naturally infected red tilapia (Oreochromis spp.)          下载免费PDF全文

Padmaja Jayaprasad Pradeep  Sarawut Sirithammajak  Jantana Kampeera  Warren Turner  Andrew Jeffs  Wansika Kiatpathomchai  Boonsirm Withyachumanarnkul 《Aquaculture Research》2017,48(6):2706-2717

Horizontal transmission of various bacterial pathogens in tilapia is well described, but there is scant information regarding their vertical transmission. This study aimed to determine the possibility of vertical transmission of two commonly reported bacterial pathogens (Francisella noatunensis subsp. orientalis and Shewanella putrefaciens) in natural stocks of red tilapia (Oreochromis spp.). Vertical transmission of these pathogens via gametes was evaluated using in vitro fertilization from 10 different families and analysing for the presence of bacteria in milt, unfertilized eggs, fertilized eggs and offspring at various ages (1‐day‐old larvae, 10‐day‐old fry and 30‐day‐old fingerlings), as well as water samples using colorimetric LAMP assay. The study revealed that both F. n. orientalis (6/10) and S. putrefaciens (4/10) was transmitted vertically to the fertilized eggs. Analysis of the water samples from different water sources (brood stock tanks, hatching chamber and larval rearing tanks) showed that both the pathogens were present in water samples with highest prevalence for F. n. orientalis followed by S. putrefaciens. Analyses for the presence of two pathogens in various organs (gonads, gill, liver, spleen, kidney and brain) of the healthy tilapia broodstock without any clinical symptoms of disease demonstrated they were carriers of S. putrefaciens and F. n. orientalis. This is the first documented evidence that vertical transmission via the broodstock of tilapia may also play an important role in transmitting these problematic pathogens to their progeny and underlines the necessity to modify the current disease management strategies in tilapia aquaculture.  相似文献   

稻麦秸秆旋耕作业中受力与位移分析     

郭俊  姬长英  Chaudhry Arslan  方会敏  张庆怡 《农业机械学报》2016,47(10):11-18

常见稻麦秸秆在实际作业过程中与刀具作用发生2种变形:挤压秸秆发生弯曲变形和剪切秸秆发生剪切变形,根据2种变形设置弯曲试验和剪切试验,分别测试15~30 mm/min加载速率下弯曲强度和剪切强度。试验结果表明,小麦秸秆抗弯强度随着加载速率增加而减小;水稻秸秆抗弯强度随着转速增加,表现为先增加后减小。小麦秸秆剪切强度随着加载速率增加,表现为先增加后减小;水稻秸秆剪切强度随着加载速率增加而增加。其次在田间试验中,根据2种变形设置横纵向秸秆以及180~280 r/min的刀轴转速,并对其反旋作业。采用同位素示踪法,即根据标记秸秆前后坐标变化值来代替机具在幅宽范围内纵横向秸秆的位移变化,将得到的标记点坐标在三维坐标系中用Matlab绘制成曲线,该曲线形状与旋耕刀片在刀轴上排列相似。耕作后位移和坐标结果表明:水稻秸秆位移大于小麦秸秆位移,水稻秸秆标记点位移变化较小麦秸秆标记点位移变化均匀;2种秸秆排列方式对应2种分布情况:纵向标记秸秆坐标在X轴上以零点对称分布,横向标记秸秆坐标在X、Z轴上两侧对称分布。基于以上因素考虑,实际作业中,选择刀轴转速230 r/min以及改变秸秆在田间排列方式,以使秸秆还田效果达到更佳。  相似文献   

Exposure to salinity stress cause ovarian disruption in a stenohaline freshwater teleost,Heteropneustes fossilis (Bloch, 1794)     

Banalata Mohanty  Kunal Gupta  Gyan Babu  Himanshu Pal  Pradeep Verma 《Aquaculture Research》2020,51(5):1964-1972

Stenohaline freshwater fish with narrow salinity tolerance are susceptible to saline stress from global climate change and anthropogenic activities. The present study elucidated that saline exposure during the sensitive window of preparatory phase of oocyte maturation significantly affected gonadosomatic index, ovarian histology and morphometric features of oocytes in a stenohaline freshwater catfish, Heteropneustes fossilis (Bloch, 1794) in a dose (2 ppt, 5 ppt)—and duration (8, 24 days)‐dependent manner. The gonads of H. fossilis show annual maturation cycle. Loss of integrity of ovigerous lamellae, disruption of ovarian stroma, disrupted oolemma, ooplasmic vacuolization, damaged germinal vesicles and altered morphometry of previtellogenic oocytes, such as chromatin‐nucleolus, early perinucleolar and late perinucleolar, elucidated consistent effects of saline exposure except at 8 days exposure to 2 ppt of saline. Increased salinity might have affected the transmembrane ion/water transport and disrupted the osmotic balance in ovary that eventually led to impairment in growth of ovary and oocyte maturation. The susceptibility of ovary to comparatively less concentrations of saline exposure might be due to sensitiveness of ovary/oocytes during the early phase of growth. Fluctuating salinity along with other stressors can affect metabolic and growth rates, fecundity and ultimately survival of fish.  相似文献   

Optimal conditions for cold-shock induction of triploidy in red tilapia     

Padmaja Jayaprasad Pradeep  Thekkeparambil Chandrabose Srijaya  Anuar Hassan  Anil Kumar Chatterji  Boonsirm Withyachumnarnkul  Andrew Jeffs 《Aquaculture International》2014,22(3):1163-1174

Production of sterile triploid red tilapia [Oreochromis mossambicus (Mozambique tilapia); Peters, 1852 × Oreochromis niloticus (Nile tilapia); Linnaeus, 1758] is an effective strategy to overcome their prolific breeding. Optimal conditions for cold-shock induction of triploidy in red tilapia were investigated by experimentally examining two variables: appropriate temperature of the shock and duration of shock treatment. A constant time after insemination of 4 min was used to determine the best combination of temperature (6, 7, 8, 9, 11, 13, 15 °C) with different durations of shock (10, 20, 30, 40, 50 min) with resultant ploidy level verified karyotypically. Shock duration for 30 min at a temperature of 9 °C was found most effective in producing maximum triploidy (98.7 %) with higher rates of hatching (63.2 %) and survival up to yolk-sac stage (75.8 %). The chromosome count confirmed that triploid percentages were higher when cold shock was used for longer durations at each temperature; however, hatching rates were generally decreased. The maximum triploid yield (82.1 %) obtained was higher than the yield obtained using heat shock (72.7 %) in red tilapia previously. The application of the results of this study has the potential to greatly improve the production of triploid red tilapia in commercial aquaculture.  相似文献   

Growth Performance of Triploid Red Tilapia Reared Under Laboratory Conditions     

Padmaja J. Pradeep  Thekkeparambil C. Srijaya  Anuar Hassan  Anil K. Chatterji  Rajeev Raghavan  Boonsirm Withyachumnarnkul 《Journal Of Applied Aquaculture》2013,25(2):176-189

Triploidy could reduce breeding activity in tilapia without the use of hormones. In this study, the effect of triploidy on survival, growth, and gender of a line of red hybrid tilapia (Oreochromis mossambicus X Oreochromis niloticus) was assessed relative to the performance of diploid siblings. Triploidy was induced by preventing second polar body extrusion by applying either heat or cold shock. Growth was similar for both ploidies during the first 90 days of culture. However, at the age of 120 days, the average body weight of triploids produced by heat shock (215.5 ± 3.61 g) was significantly higher than that of cold shock (192.7 ± 2.6 g) and the diploid control (191.9 ± 1.74 g). Survival among triploids was inferior to diploids. Percentage of males in the triploid population was 82.9% in the heat-shocked treatment group, 54.8% in the cold-shock treatment, and 50% in the diploid control. Maximum attainable weight of red tilapia was calculated by applying the Ford-Walford growth plot: 650 g (heat-shocked triploids), 490 g (cold-shocked triploids), and 440 g in the diploid control.  相似文献   

Evaluation of potato seed tubers from different sources in the Punjab plain of Pakistan     

Altaf Hussain Chaudhry  Syed Mahfooz Ali Shah  Kh. Imdad Hussain  Ch. A. H. Tariq  Raymon E. Webb 《American Journal of Potato Research》1984,61(11):703-709

Inability to produce large quantities of high quality, relatively diseasefree potato seed is a major constraint to providing economic support to a highly important and rapidly expanding potato production industry in Pakistan. Studies were undertaken for 5 years to evaluate productivity of seed of cultivars Red Bad, Ajax, Atica, Patrones, Montana, Cosima, Desiree, and Cardinal grown at five environmentally diverse locations in Pakistan versus seed of the same cultivars imported from Europe. The productivity trials were conducted during the autumn and spring seasons at the Ayub Agricultural Research Institute, Faisalabad (Punjab Plains). The results from the 5-year test period indicate that seed of each of the cultivars produced in the high hills (Baluchistan, Northwest Frontier Province) and during autumn (September to December) in the Punjab Plains, the latter cold stored until the following September, are equally as productive as seed imported from Europe.  相似文献   

In Vitro and In Silico Characterization of G-Protein Coupled Receptor (GPCR) Targets of Phlorofucofuroeckol-A and Dieckol     

Pradeep Paudel  Su Hui Seong  Se Eun Park  Jong Hoon Ryu  Hyun Ah Jung  Jae Sue Choi 《Marine drugs》2021,19(6)

Phlorotannins are polyphenolic compounds in marine alga, especially the brown algae. Among numerous phlorotannins, dieckol and phlorofucofuroeckol-A (PFF-A) are the major ones and despite a wider biological activity profile, knowledge of the G protein-coupled receptor (GPCR) targets of these phlorotannins is lacking. This study explores prime GPCR targets of the two phlorotannins. In silico proteocheminformatics modeling predicted twenty major protein targets and in vitro functional assays showed a good agonist effect at the α2C adrenergic receptor (α_2CAR) and an antagonist effect at the adenosine 2A receptor (A_2AR), δ-opioid receptor (δ-OPR), glucagon-like peptide-1 receptor (GLP-1R), and 5-hydroxytryptamine 1A receptor (5-TH_1AR) of both phlorotannins. Besides, dieckol showed an antagonist effect at the vasopressin 1A receptor (V_1AR) and PFF-A showed a promising agonist effect at the cannabinoid 1 receptor and an antagonist effect at V_1AR. In silico molecular docking simulation enabled us to investigate and identify distinct binding features of these phlorotannins to the target proteins. The docking results suggested that dieckol and PFF-A bind to the crystal structures of the proteins with good affinity involving key interacting amino acid residues comparable to reference ligands. Overall, the present study suggests α_2CAR, A_2AR, δ-OPR, GLP-1R, 5-TH_1AR, CB₁R, and V_1AR as prime receptor targets of dieckol and PFF-A.  相似文献   

IMAGING OF PHEOCHROMOCYTOMA IN 2 DOGS USING p-[¹⁸F] FLUOROBENZYLGUANIDINE     

Clifford R.  Berry  DVM  Timothy R.  Degrado  PhD  Felicia  Nutter  DVM  Pradeep K.  Garg  PhD  Edward B.  Breitschwerdt  DVM  MS  Kathy  Spaulding  DVM  Kevin D.  Concannon  DVM  Michael R.  Zalutsky  PhD  R. Edward Coleman    MD 《Veterinary radiology & ultrasound》2002,43(2):183-186

p-[18F]Fluorobenzylguanidine ([18F]PFBG) is a norepinephrine analog that has been developed as a positron emission tomography (PET) imaging radiopharmaceutical. Myocardial sympathetic innervation, neuroendocrine structures, and tumors can be noninvasively imaged with [18F]PFBG. In this study, the uptake characteristics of [18F]PFBG were investigated in 2 dogs with a spontaneous pheochromocytoma. The extent of the pheochromocytoma was well documented in both dogs on the PET study. The standardized uptake values within the pheochromocytomas were greater than 25 by 10 min, and were 37 and 50 by 45 min in each dog. A third dog that was suspected to have an adrenal mass was also studied. In this dog, the [18F]PFBG study was normal. Surgical exploration and adrenal biopsy confirmed the [15F]PFBG imaging findings in both dogs. In each dog, there was rapid blood-pool clearance (within 10 min after intravenous administration of the [18F]PFBG), with high uptake specific within the myocardium and adrenal medulla. The results indicate that [18F]PFBG may be useful for imaging canine pheochromocytomas and aid in differentiating adrenal masses.  相似文献