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101.
Muhammad Shahid Tiantian Xiong Nasir Masood Tibo Leveque Katelle Quenea Annabelle Austruy Yann Foucault Camille Dumat 《Journal of Soils and Sediments》2014,14(4):655-665
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102.
Muhammad Youssef Arif Saeed Alhammadi Jorge Humberto Ramírez-Prado Lorenzo Felipe Sánchez-Teyer Rosa María Escobedo-GraciaMedrano 《Genetic Resources and Crop Evolution》2018,65(2):577-590
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
103.
104.
Naeem AbbasSarfraz Ali Shad Muhammad Razaq 《Pesticide biochemistry and physiology》2012,103(3):181-188
Imidacloprid has been used as a key insecticide for controlling sucking insect pests of cotton, whereas Spodoptera litura also has been indirectly exposed to this insecticide in Pakistan. To evaluate the risk of resistance evolution and to develop a better resistance management strategy, a field collected population was selected with imidacloprid in the laboratory. Thereafter, fitness cost, realized heritability and cross resistance of imidacloprid resistance in S. litura were investigated. After 14 generations of selection with imidacloprid, S. litura developed a 137.48-fold resistance to the insecticide. Bioassay revealed that this strain showed cross-resistance to acetamiprid (RR 8.52) and a little to lamdacyhalothrin (1.92) but negative cross-resistance was found to methomyl (−0.19). The resistant strain had a relative fitness of 0.38, with substantially lower rates of larval survival, larval duration, male pupal duration, development time, emergence rate of healthy adults, fecundity, hatchability, and prolonged larval and pupal duration. Mean relative growth rate of the larvae, intrinsic rate of population increase, and biotic potential was lower for the selected populations. The estimated realized heritability (h2) of imidacloprid resistance was 0.15 in the resistant strain of S. litura. Development of the resistance may cost significant fitness for the resistant population. This study provided valuable information for further understanding the impact of imidacloprid resistance on physiological parameters of S. litura and for facilitating the development of resistance management strategies. 相似文献
105.
Shahid Hussain Muhammad Aamer Maqsood Zed Rengel Muhammad Khawar Khan 《Euphytica》2012,186(1):153-163
Estimating variation in grain mineral concentration and bioavailability in relation to grain yield and the year of cultivar
release is important for breeding wheat with increased content of bioavailable minerals. The grain yield and yield components,
grain phytate concentration, and concentration and bioavailability of minerals (zinc Zn, iron Fe and calcium Ca) in wheat
grains were estimated in 40 wheat cultivars released in Punjab (Pakistan) during the last five decades. Mean grain Zn and
Ca concentrations in current-cultivars were significantly lower (≥14%) than in obsolete cultivars released during the Green
Revolution (1965–1976). Much of this variation was related to increased grain weight in current-cultivars. There was a positive
correlation among minerals (r = 0.39 or higher, n = 40) and minerals with phytate in wheat grains (r = 0.38 or higher, n = 40). The tested cultivars varied widely in grain yield and grain phytate-to-mineral molar ratios (phytate:mineral). Compared
to obsolete cultivars, the current-cultivars had a higher phytate:mineral ratio in grains, indicating poor bioavailability
of minerals to humans. The study revealed a non-significant relationship between grain yield and phytate:mineral ratios in
grains. Therefore, breeding for lower phytate:mineral ratios in wheat grains can ensure increased mineral bioavailability
without significant reduction in the yield potential. Future breeding should be focused on developing new genotypes suitable
for mineral biofortification and with increased mineral bioavailability in grains. 相似文献
106.
Okab AB Ayoub MA Samara EM Abdoun KA Al-Haidary AA Koriem AA Hassan AA 《Tropical animal health and production》2012,44(7):1623-1629
Twenty-five intact Barki lambs with mean body weight of 24.81 ± 0.16?kg were used to investigate the effect of including in the diet sugar beet pulp (SBP) treated biologically with Trichoderma reesei or chemically with urea 4 % on nutrients digestibility, growth performance, nitrogen (N) utilization, and hematological and biochemical parameters. Two experiments were conducted. In the growth experiment, five lambs were randomly assigned to one of five dietary treatments. Lambs were offered isonitrogenous and isoenergetic concentrate feed mixture containing on dry matter basis 0 % SBP (D0), 50 % SBP (D1), 50 % SBP treated with 4 % urea (D2), 50 % SBP treated with T. reesei (D3), and 25 % SPB treated with 4 % urea plus 25 % SPB treated with T. reesei (D4). In the metabolism experiment, five rams were used in a 5?×?5 Latin square design and housed in metabolism crates for 21?days. The present study showed that inclusion of SBP at the level of 50 % (D1) negatively affected diet digestibility coefficients of crude protein, crude fiber, and ether extract, in addition to average daily gain, feed conversion, and N utilization. However, treatment of SBP with urea (D2), T. reesei (D3), or the combination (D4) of both had improved (P?0.05) these parameters with superiority of D3. Despite the significant differences in the tested hematological and biochemical parameters of lambs fed on biologically or chemically treated SBP diets, their levels remained within the physiological ranges which could indicate that treated SBP did not have any adverse effect on lambs' health. 相似文献
107.
Awais MM Akhtar M Iqbal Z Muhammad F Anwar MI 《Tropical animal health and production》2012,44(2):323-328
The present paper reports the prevalence of coccidiosis in industrial broiler chickens in Faisalabad, Punjab, Pakistan to
determine the occurrence of different species of Eimeria in the area and to assess their correlation with the environmental conditions including temperature, humidity and rainfall.
The study was conducted from January 2009 to December 2010. Examination of chicken guts revealed 43.89% (n = 3,283/7,480) prevalence of coccidiosis. The highest prevalence (27.04%) was recorded of Eimeria tenella followed by Eimeria maxima (22.42%), Eimeria acervulina (19.89%) and Eimeria necatrix (4.02%). The prevalence of disease was significantly higher (P < 0.05) in autumn (60.02 ± 4.38) followed by summer (47.42 ± 2.92), spring (36.92 ± 2.27) and winter (29.89 ± 3.43). Likewise,
prevalence of different species of Eimeria also varied (P < 0.05) in different seasons of the year except that of E. necatrix. A strong correlation (P < 0.05) of environmental conditions with the overall and species-wise prevalence of coccidiosis was recorded except E. necatrix. 相似文献
108.
Hussain R Auon M Khan A Khan MZ Mahmood F Ur-Rehman S 《Tropical animal health and production》2012,44(3):477-481
Seroprevalence, clinical findings, and lesions of contagious caprine pleuropneumonia (CCPP) in Beetal goats were recorded
during an outbreak. The overall seroprevalence of CCPP was 32.50%. Confirmation of Mycoplasma mycoides in serum was carried out using counter immunoelectrophoresis (CIE) technique. The highest CIE-positive cases were recorded
in the older goats (51.72%) as compared to young ones. Nasal swabs collected from 39 goats showing respiratory signs were
found positive for M. mycoides. The most consistent clinical findings were mild to severe cough, purulent nasal secretion, emaciation, dyspnea, increased
respiration rate, and pyrexia. Mortality due to CCPP was 9.17%. Consolidation of lungs exhibited the highest frequency (100%),
followed by alveolar exudation (90.90%) and pleural adhesion (72.72%). Among the microscopic lesions, septal peribronchiolar
fibrosis exhibited the highest frequency (81.81%), followed by fibrinous pleuritis (63.63%) and peribronchiolar cuffing of
mononuclear cells (54.54%) in lungs. From these results, it was concluded that CCPP under subtropical conditions has high
prevalence in Beetal goats and leads to significant mortality. 相似文献
109.
Syed Ajijur Rahman Muhammad Hasan Imam Denyse J. Snelder Terry Sunderland 《Small-Scale Forestry》2012,11(4):529-538
In the Padma floodplain of Bangladesh, the traditional system of agriculture has become unsustainable due to high population growth. Mango-based agroforestry which has been practiced by the farmers since the 1990s, is a promising alternative and is considered as one of the few options to lift farmers out of poverty and improve livelihood security. This paper examines the potential of mango-based agroforestry to improve livelihoods, using data collected by rapid rural appraisal, farmer participatory research, stakeholder analysis and a farm household survey in six representative villages in the floodplain. Farmers with the least land were found to allocate a higher percentage of their land to agroforestry, and the increased income from agroforestry compared to other agricultural systems helps reduce relative poverty. This income maintains basic household needs, providing food security and fuelwood, and contributes to healthcare, housing and sanitation conditions, and meeting educational expenses. 相似文献
110.
Kazmi I Rahman M Afzal M Gupta G Saleem S Afzal O Shaharyar MA Nautiyal U Ahmed S Anwar F 《Fitoterapia》2012,83(1):142-146
A new stearoyl glucoside of ursolic acid, urs-12-en-3β-ol-28-oic acid 3β-d-glucopyranosyl-4′-octadecanoate and other compounds were isolated from the leaves of Lantana camara L. The structure of this new glycoside was elucidated and established by standard spectroscopic methods. In streptozotocin-induced diabetic rats it showed significant reduction in blood glucose level. 相似文献