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71.
Growth,survival, and heavy metal (Cd and Ni) uptake of spinach (Spinacia oleracea) and fenugreek (Trigonella corniculata) in a biochar‐amended sewage‐irrigated contaminated soil 下载免费PDF全文
Uzma Younis Muhammad Farooq Qayyum M. Hasnain Raza Shah Subhan Danish Ahmad Naeem Shahzad Saeed Ahmad Malik Seema Mahmood 《植物养料与土壤学杂志》2015,178(2):209-217
Irrigation of arable land with contaminated sewage waters leads to the accumulation of trace metals in soils with subsequent phyto‐/zootoxic consequences. In this study, biochar derived from cotton sticks was used to amend an agricultural silt‐loam soil that had been previously irrigated with trace metal contaminated sewage waters. Metal accumulation and toxicity to spinach (Spinacia oleracea) and fenugreek (Trigonella corniculata) was investigated by measuring concentrations of Cd and Ni in plant tissues and various photosynthetic and biochemical activities of plants. Positive impacts of biochar on both spinach and fenugreek were observed in terms of biomass production that increased from 29% to 36% in case of spinach, while for fenugreek this increase was 32% to 36%. In the control treatment there was an increase in malondialdihyde, soluble sugar, and ascorbic acid contents, indicating heavy metal stress. Biochar applications increased soluble proteins and amino acids in plants and reduced the uptake of Cd from 5.42 mg kg?1 at control to 3.45 mg kg?1 at 5% biochar amended soil and Ni (13.8 mg kg?1 to 7.3 mg kg?1 at 5% biochar) by the spinach plants. In fenugreek, the Cd was reduced from 7.72 mg kg?1 to 3.88 mg kg?1 and reduction in Ni was from 15.45 mg kg?1 to 9.46 mg kg?1 at 5% biochar treated soil, reducing the possibility of transfer up the food chain. This study demonstrates that the use of biochar made from cotton‐sticks, as an amendment to arable soils that have received contaminated irrigation water, could improve plant growth and decrease Cd and Ni uptake to crops, alleviating some of the negative impacts of using sewage waters on arable land. 相似文献
72.
73.
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
74.
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
75.
76.
Mahr-un-Nisa Shahzad MA Phillips CJ Sarwar M 《Tropical animal health and production》2012,44(5):947-952
Urea is a common ingredient of the diets of intensively fed lambs, but is increasingly required for industrial processes.
Maize steep liquor (MSL) is a by-product of maize grain degradation to produce starch that may be a suitable replacement.
Fifty growing lambs were fed on equinitrogenous diets in which between 0% and 80% of the urea was replaced by MSL; their growth
and metabolism were recorded over 70 days. Increasing replacement of urea by MSL increased feed intake and nutrient digestibilities,
leading to increased growth rates, more efficient feed conversion, and increased nitrogen retention. Concentrations of triiodothyroxin,
thyroxin, glucose, and methionine were increased by replacement of urea by liquor, and plasma urea was reduced. This study
suggests that MSL is a suitable replacement for up to 80% of urea in the diet of rapidly growing lambs. 相似文献
77.
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
78.
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
79.
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
80.
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