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Stripe rust is a continuous threat to wheat crop all over the world. It causes considerable yield losses in wheat crop every year. Continuous deployment of adult plant resistance(APR) genes in newly developing wheat cultivars is the most judicious strategy to combat this disease. Herein, we dissected the genetics underpinning stripe rust resistance in Pakistani wheat germplasm. An association panel of 94 spring wheat genotypes was phenotyped for two years to score the infestation of stripe rust on each accession and was scanned with 203 polymorphic SSRs. Based on D' measure, linkage disequilibrium(LD) exhibited between loci distant up to 45 c M. Marker-trait associations(MTAs) were determined using mixed linear model(MLM). Total 31 quantitative trait loci(QTLs) were observed on all 21 wheat chromosomes. Twelve QTLs were newly discovered as well as 19 QTLs and 35 previously reported Yr genes were validated in Pakistani wheat germplasm. The major QTLs were QYr.uaf.2 AL and QYr.uaf.3 BS(PVE, 11.9%). Dissection of genes from the newly observed QTLs can provide new APR genes to improve genetic resources for APR resistance in wheat crop.  相似文献   
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Tropical Animal Health and Production - Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis, a debilitating chronic disease of sheep and goats. Little is known about...  相似文献   
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Excessive and inappropriate use of fertilizers is a key factor of low sugarcane yield and degradation of soil. A two-year (2013–14 and 2014–15) field study was conducted to assess the impact of combined application of organic and inorganic fertilizers on sugarcane at research farm of Shakarganj Sugar Research Institute, Jhang, Pakistan. Experiment was conducted under randomized complete block design with three replications. Treatments were used as control (no exogenous application), spent wash (160 t ha?1), (nitrogen, phosphorus and potassium) NPK (168:112:112 kg ha?1), spent wash (120 t ha?1) + NPK (42:28:28 kg ha?1), spent wash (80 t ha?1) + NPK (84:56:56 kg ha?1), spent wash (40 t ha?1) + NPK (126:84:84 kg ha?1), and spent wash (160 t ha?1) + NPK (42:28:28 kg ha?1). Application of spent wash @ 80 t ha?1 + NPK @ 84:56:56 kg ha?1 resulted maximum crop growth rate (11.35 g m?2 d?1), leaf area index (7.78), and net assimilation rate (2.53 g m?2 d?1). Maximum number of millable canes (14), weight per stripped cane (0.90 kg), stripped cane yield (117.60 t ha?1) and unstripped cane yield (141.25 t ha?1) were observed with spent wash @ 80 t ha?1 + NPK @ 84:56:56 kg ha?1, followed by sole fertilizer application @ 168:112:112 kg NPK ha?1 and spent wash @160 t ha?1 + NPK @ 42:28:28 kg ha?1. Similar trend was observed regarding quality parameters. The maximum benefit–cost ratio (1.80) was achieved with integrated application of spent wash @ 80 t ha?1 + NPK @ 84:56:56 kg ha?1.  相似文献   
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The Tigray Plateau of Ethiopia and Eritrea is vulnerable to environmental change, yet environmental influences on the rise and fall of the civilizations that once existed there are almost unexplored. We sampled sections of gully walls for palaeoenvironmental proxies from two sites: 1) Adi Kolen on the southern outskirts of the Plateau's most developed former empire, the Aksumite, and 2) Adigrat near polities dating to at least ca. 3000 cal yr BP. A multi-proxy approach for examining local variation in palaeoenvironments was evaluated that included stable isotopic and elemental analyses (δ13CSOM, δ15N, %TOC, and %TN) of soil, and charcoal identification. An increase in δ15N values from older soils in Adi Kolen (4400 cal yr BP) and Adigrat (2900 cal yr BP) until 1200 cal yr BP is not explained by changes in δ15N that occur with time in an unchanging environment. It may instead indicate an overall decrease in rainfall from the earlier times until 1200 cal yr BP. In one Adigrat section, the decreases in organic δ13C and increases in C/N molar ratios from older to younger soil could have resulted from changes that occur over time, per se. In the remaining sections, however, δ13CSOM trends more likely reflect changes in the biomass of C4 relative to C3 plants (% C4 biomass). Changes in% C4 biomass may reflect climate and/or land use. Deciphering which may be aided by analyses of the other proxies. Identified charcoal suggests that both sites supported some juniper forest types until very recently but that forests may have been a more important and dynamic component of Adigrat's vegetation history than Adi Kolen's. If environment affected the trajectories of the kingdoms of the Tigray Plateau, these results suggest that the exact nature of the changes in climate differed among kingdoms. The kingdoms prior to 1200 cal yr BP may have been exposed to increasing aridity punctuated with relatively wetter intervals. Thereafter, general changes in climate are not apparent. Land clearing dynamics are likely to have had a more consistent effect on the trajectories of kingdoms than climate changes.  相似文献   
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【目的】西瓜是一种广受欢迎的夏季水果,籽用西瓜(籽瓜)、黏籽西瓜和普通西瓜是3种重要的栽培类型,但对其果实中代谢物全面鉴定的研究很少,比较这3种西瓜果实的代谢组学差异,为明确驯化改良对不同类型西瓜代谢组的影响提供新见解。【方法】试验以5份籽用西瓜、5份黏籽西瓜和6份普通西瓜为材料,对成熟期果肉进行广泛靶向代谢组学检测,采用SIMCA-P、MetaboAnalyst 5.0、Origin等软件对代谢组数据进行分析。【结果】LC-MS分析共检测到323种代谢物,包括51种氨基酸及其衍生物、21种核苷酸及其衍生物、14种碳水化合物、32种有机酸、52种脂质、36种类黄酮、32种羟基肉桂酰衍生物等。PCA和聚类分析显示,籽用西瓜和黏籽西瓜的代谢组学轮廓差异较小,籽用西瓜的代谢组轮廓介于黏籽西瓜和普通西瓜之间。对分类贡献率较大的代谢物是蔗糖、柠檬酸、L-谷氨酸、L-苏氨酸、葫芦素类、香草酸糖苷异构体、脂质类等。聚类热图分析显示黏籽西瓜中特有的代谢物是葫芦素及其衍生物等,籽用西瓜中的绿原酸、LysoPE脂质类等化合物含量较高,普通西瓜中的糖类、精氨酸、阿魏酸及C18-2和C18-3不饱和脂肪酸等物质含量较高。比较分析共鉴定出156种差异代谢物,籽用西瓜与黏籽西瓜的主要差异代谢物有对香豆醛、阿魏酸、肉桂酸、蔗糖、葫芦素D O-葡萄糖苷、葫芦素E异构体、牡荆素、松柏醇等。籽用西瓜与普通西瓜的主要差异代谢物有脂质类、类黄酮类、有机酸类和糖类等。随着作物进化的程度增加,营养类代谢物质含量增加,抗性相关的代谢物质含量减少。【结论】籽用西瓜和黏籽西瓜的果实代谢组差异比籽用西瓜和普通西瓜的差异小,籽用西瓜的代谢轮廓介于黏籽西瓜和普通西瓜之间。除了表型和基因组差异外,代谢组差异也可以作为区分品种的重要依据。本研究首次在代谢组学水平比较了3种类型西瓜果实的差异,对深入理解西瓜种质资源,培育保健型西瓜新品种有重要的指导意义。  相似文献   
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Dairy farming is vulnerable to global warming and climate change. Improving and maintaining conception rates (CRs) have a paramount importance for the profitability of any dairy enterprise. There is an antagonistic relationship between fertility and milk yield, and intensive selection for milk yield has severely deteriorated reproductive efficiency. Irrespective of geography and husbandry, modern dairy cows experience heat stress (HS) effects leading to fertility declines, but it worsens in tropical climates. The threshold of HS experience among modern dairy cow has lowered, leading to decreased thermal comfort zone. Studies show that this threshold is lower for fertility than for lactation. HS abatement and robustness response to lactation yield lead to negative energy balance, and cow's reproductive requirements remain unfulfilled. The adverse effects of HS commence from developing oocyte throughout later stages and its fertilization competence; the oestrus cycle and oestrus behaviour; the embryo development and implantation; on uterine environment; and even extend towards foetal calf. Even cows can become acyclic under the influence of HS. These harmful effects of HS arise due to hyperthermia, oxidative stress and physiological modifications in the body of dairy cows. Proper assessment of HS and efficient cooling of dairy animals irrespective of their stage of life at farm is the immediate strategy to reduce fertility declines. Other long- and short-term mitigation strategies to reduce fertility declines during HS include feeding care, reducing disease and mastitis rates, using semen from cooled bulls, timed artificial inseminations (AI), allied hormonal interventions and use of embryo transfer technology. Ultimate long-term solution should be well-planned breeding for fertility improvement and HS tolerance.  相似文献   
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World over the traditional knowledge has always formed the foundation for development of modern medicines as a result of scientific follow up of the traditional knowledge. Andaman archipelago represents one of the greatest emporia of ethno botanical wealth in India where aboriginal native tribes of ancient culture remain in their virginity and possess abundant ethnic knowledge. The Jarawas of Andaman Island are one such primitive and dwindling community. Jarawas inhabit the Jarawa Reserve located along the western parts of the South and Middle Andamans. A brief account of anthropology of the tribe is given. Results of ethnobotanical studies of Jarawa tribe have been enumerated which revealed interesting plants which can be further prioritized for scientific evaluation and Bioprospection for product development. The species like Alpinia manii, Amomum aculeatum, belonging to Zingiberaceae and Pseuduvaria prainii, Orophea katschallica of Annonaceae are shown to have effective insect and bee repellent properties. Such leads should be subjected to further scientific scrutiny for development of global level products having mosquito and other disease causing insect repellent properties. While this achieves the human welfare aspects, at the same time boosts the economy of the region. The Jarawas possess extensive knowledge of the plants of the surrounding forests and use them in their daily life for food, medicine, shelter, fibres, ornaments, bows and arrows and for many other needs. Such plants are enumerated with correct botanical names, family, Jarawa names, plant parts used along with details of use.  相似文献   
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