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71.
Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. granatum L., were compared for the first time. Analysis of one P. protopunica and eleven P. granatum accessions was performed using three molecular markers, i.e., sequence related amplified polymorphism (SRAP), target region amplification polymorphism (TRAP), and intron targeted amplified polymorphism (ITAP), along with analysis of pgWD40 sequences, a gene involved in anthocyanin biosynthesis. All markers revealed the relationship between the two species and placed them at 33% similarity. SRAP, TRAP, and ITAP generated a total of 299, 260, and 160 bands, respectively. Of these, 78, 74, and 41 bands were specific for P. protopunica, and 92, 85, and 57 bands, respectively, were shared between both species. Sequence analysis of pgWD40~870 bp amplicons exhibited 100% identity among P. granatum accessions and 98% identity to that of P. protopunica. Phylogenetic analysis of WD40 sequences from monocot and dicot species, including both Punica species confirmed the relation between P. protopunica and P. granatum, supporting earlier reports that P. protopunica could be an ancestral species of P. granatum. Furthermore, the genetic diversity among and within P. granatum accessions from Egypt (3), Mexico (5), and Yemen (3) was assessed. Molecular marker-based relationships among region-bulked accessions was approximately the same (~90% similarity), whereas the degree of genetic variation was altered within each region. Specific bands (alleles) for accessions of each region along with those shared among them were identified. Thus, these bands could be used for pomegranate genotyping and breeding programs.  相似文献   
72.
A field experiment was conducted to evaluate effect of biochar-amended urea on nitrogen economy of soil for improving the growth and yield of wheat under field condition. Experiment plan was comprised of twelve treatments with four replications including treatments without application of urea and biochar (control) and urea only. Biochar was applied at 1–10% of the weight of urea fertilizer applied each treatment. Results showed that application of biochar at 10% with recommended dose of urea significantly improved plant height, spike length, number of tillers, number of spikelet per spike, 1000 grain weight, grain yields, biomass yield, harvesting index, nitrogen (N) concentration and uptake in grain and straw, and agronomic efficiency of nitrogen by 6.0%, 11.1%, 32.0%, 55.3%, 5.4%, 38.0%, 19.0%, 9.0%, 19.0%, 26.0%, 65.0%, 50.0%, and 63.0%, respectively, as compared to treatment comprised of recommended rate of nitrogen without biochar.  相似文献   
73.
Cr3+ sorption on strong acid exchanger Amberlyst-15(H+) is studied as a function of time and temperature using CrCl3.6H2O and [Cr4(SO4)5(OH)2] solutions. The rate is found to be governed by a mixed diffusion for both the solutions and faster for Cl1? solution than SO4 2?. The exchange capacities are found to be higher for Cl1? system than SO4 2?. From the rate constant values, the energies of activation are calculated using the well-known Arrhenius equation. Equilibrium data is explained with the help of the Langmuir equation. The Langmuir parameters are also found to be higher for exchange from the chloride solutions. Various thermodynamic parameters (??Ho, ??So, and ??Go) for Cr3+ exchange on the resin are calculated. The ??Go values are found to be negative while ??Ho and ??So are positive for both the Cr3+/Cl1? and Cr3+/SO4 2? systems. It is suggested that in case of Cl1? solutions, the metal is exchanged as Cr3+, while in case of SO4 2? solutions, the metal exchanging specie is CrSO4 +.  相似文献   
74.
Asian bears face major threats due to the impact of human activities as well as a critical lack of knowledge about their status, distribution and needs for survival. Once abundant in northern Pakistan, the Himalayan brown bear (Ursus arctos isabellinus) has been exterminated in most of its former distribution range. It presently occurs sparsely, in small populations, the Deosai National Park supporting the largest isolate. This decline might imply a reduction in genetic diversity, compromising the survival of the population. Using a combination of fecal DNA analysis and field data, our study aimed at assessing the size and genetic status of the Deosai population and give guidelines for its conservation and management. Using fecal genetic analysis, we estimated the population to be 40-50 bears, which compares well with the field census of 38 bears. The northern Pakistani brown bear population may have undergone an approximate 200-300-fold decrease during the last thousand years, probably due to glaciations and the influence of growing human population. However, in spite of the presence of a bottleneck genetic signature, the Deosai population has a moderate level of genetic diversity and is not at immediate risk of inbreeding depression. Gene flow might exist with adjacent populations. We recommend careful monitoring of this population in the future both with field observations and genetic analyses, including sampling of adjacent populations to assess incoming gene flow. The connectivity with adjacent populations in Pakistan and India will be of prime importance for the long-term survival of Deosai bears.  相似文献   
75.
Ten agricultural soils were spiked with 100 μg of Cu, Zn, and Pb g?1 of soil. The complexation of Pb by 10?4 M DTPA was determined after 60 days of metal equilibrium. A theoretical stability model of Fe, Mn, Cu, Zn, Ca, and Pb, between pH 1 and 10 was developed. It showed that CuL3? (55.4 to 63%), CuHL2? (0.1 to 9.4%), PbL3? (29.1 to 33.3%), PbHL2? (0.01 to 2.5%) and MnL3? (2.8 to 3.2%) as the predominant species between pH 6 and 9. Other species like CaL3?, CaHL2?, FeL2?, FeHL?, FeL3?, FeHL2?, ZnL3?, ZnHL2? and MnHL2? were less than 0.1% between pH 6 and 9. In the experimental soils, DTPA-Pb complexes accounted for 12.3 to 21.2% of metal complexed after 3 days of DTPA equilibriation. DTPA-Cu complexes were the major complexed species in the soils ranging between 72.5 and 82.2% after 3 days equilibriation with 10?4 M DTPA. The proportion of Zn complexed by DTPA (3.8 to 10.1%) was much greater than predicted by the theoretical model. On the contrary, Mn was not complexed in appreciable amounts by DTPA.  相似文献   
76.

Bluetongue virus (BTV), a member of Orbivirus genus (family Reoviridae), is a non-contagious infection of domestic and wild ruminants. The current study was designed to detect various serotypes of BTV in small ruminants of Khyber Pakhtunkhwa (KPK) province of Pakistan, along with their effects on hemato-biochemical parameters. A total of 408 serum samples in four districts (Mansehra, Abbottabad, Swabi, and Kohat) of KPK from small ruminants were screened based on competitive ELISA (cELISA). A total of 204 (50%) samples were found positive for BTV group–specific antibodies. The seropositive samples were processed for the detection of BTV serotypes through real-time polymerase chain reaction (qPCR). Out of 204 cELISA-positive samples, 60 (29.41%) were found positive through qPCR. Three serotypes [6, 8, 9] were detected from Mansehra District and two from Kohat [2, 8] and Abbottabad [6, 8], while only one from Swabi [8]. The serotype “8” was found consistently in all the four study districts. A significant (p?<?0.05) increase in the level of blood urea nitrogen (BUN) and alkaline phosphatase (ALP) was recorded in goats, whereas aspartate aminotransferase (AST) in sheep infected with BTV, compared to healthy animals. The hematological parameters showed significantly (p?<?0.05) raised total leucocyte count (TLC) in both sheep and goats, whereas only hematocrit (HCT) value was increased significantly (p?<?0.05) in infected sheep. This is the first report on serotyping of BTV among small ruminants in Pakistan.

  相似文献   
77.
辣椒热泵干燥特性及工艺参数优化   总被引:4,自引:3,他引:4  
为了提高干制辣椒品质,降低干燥能耗,该文应用热泵干燥技术干燥辣椒。首先探究干燥温度和铺料厚度对干燥特性的影响,绘制出含水率和干燥速率变化曲线。在此基础上,将分阶段控温和改变铺料厚度结合起来对辣椒进行热泵干燥,运用响应面法中的Box-Behnken设计,考察第一阶段温度、第二阶段温度、铺料厚度和三者的交互作用对品质得分、单位能耗、干燥时间的影响,并建立回归方程,得出最佳工艺参数。结论如下:温度越高,干燥速率越大,含水率下降越快;铺料厚度越大,干燥速率越小,含水率下降越慢;第一阶段温度是影响单位能耗的主要因素(P0.05),较低的第一阶段温度能降低单位能耗;第二阶段温度对品质得分影响显著(P0.05),对干燥时间影响极显著(P0.01),第二阶段温度在60℃左右时能得到品质较佳的干辣椒,且在一定程度上提高了干燥效率;铺料厚度对品质得分、干燥时间的影响极显著(P0.01),对单位能耗的影响显著(P0.05),铺料厚度在45 mm左右干燥获得的辣椒品质较佳,而且能节约能耗,提高干燥效率。综合优化参数为:第一阶段温度48℃、第二阶段温度61℃、铺料厚度44 mm,在此工艺条件下获得的干燥辣椒品质得分为8.64,单位能耗为92.05 k J/kg,干燥时间为896.02 min。研究结果为热泵干燥技术应用于辣椒干制提供参考。  相似文献   
78.

Purpose

The present research aimed to assess the influence of two phosphorous (P) amendments on metal speciation in rhizosphere soil and the soil–plant transfer of metals.

Materials and methods

Complementary experiments were performed: field experiments on a contaminated cultivated soil and laboratory experiments on an uncultivated contaminated soil to highlight the mechanisms involved in metal-phosphorous interactions. In laboratory experiment, P amendments were added at 120 mg P/kg of soluble KH2PO4 amendment and 9,000 mg P/kg of solid Ca5(PO4)3OH amendment.

Results and discussion

Field-culture results showed the possible food-chain contamination due to Pb, Cd, Cu, and Zn phytoaccumulation by pea and mustard plants from a cultivated agricultural soil. Moreover, P-metal complexes were observed by microscopy in the rhizosphere soil. In laboratory experiments, the application of P amendments significantly increased Pb and Zn level in rhizosphere soil compared to control. Phosphate amendments significantly increased metal-P fraction and decreased “oxides” and “organic matter” fractions of Pb and Zn. Soluble-P amendment was more effective than solid P amendment in changing Pb and Zn speciation. The changes in metal speciation are higher in the rhizosphere soil of pea than tomato. Application of P amendments increased Pb and Zn TF root/soil but decreased TF shoot/root.

Conclusions

The effectiveness of in situ metal immobilization technique varies with the type and quantity of applied P amendment as well as plant and metal type.  相似文献   
79.
Zizyphus oxyphylla Edgew is used in Pakistan as a folk medicinal remedy for inflammatory conditions, pains especially rheumatic pain, fevers, allergy and diabetes. The aim of the current study was to scientifically validate the folk use of Z. oxyphylla Edgew by using the isolated compound in vitro and in vivo levels. Kushecarpin A was isolated from ethyl acetate fraction of the plant crude extract. Molecular docking simulations predicted Kushecarpin A as a potential new lipoxygenase (LOX) inhibitor. Kushecarpin A showed significant lipoxygenase inhibition (IC50: 7.2 ± 0.02 μM) thus validated computational prediction. It also exhibited significant and highly significant inhibition (p < 0.05 and p < 0.01) of carrageenan-induced hind paw oedema at the doses of 5, 10 and 20 mg/kg. Kushecarpin A seems to be a potentially new anti-inflammatory compound responsible for anti-inflammatory activities of Z. oxyphylla Edgew. In vitro and in vivo anti-inflammatory inflammatory activities were found in good agreement with the folk medicinal use of Z. oxyphylla Edgew in inflammatory disorders.  相似文献   
80.
Seed presoaking improves wheat germination under marginal moisture conditions. The duration of seed presoaking was studied at The University of Arid Agriculture, Rawalpindi, using 10 wheat varieties. Seed presoaking beyond 12 h does not improve germination further, and beyond 21 h, germination rate is drastically reduced.  相似文献   
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