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41.
Two mustard (Brassica juncea L. Czern and Coss.) cultivars, Pusa Jai Kisan and SS2 differing in cadmium (Cd) tolerance were treated with 0, 25 and 50 umol L-1 Cd to study the physiological basis of difference in Cd tolerance. Cultivar SS2 (Cd sensitive) accumulated greater Cd in leaves than Pusa Jai Kisan (Cd tolerant). Further, SS2 also exhibited higher contents of thiobarbituric acid reactive substances (TBARS) and H2O2 and electrolyte leakage. However, the activities of antioxidant enzymes, catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reduetase (DHAR), and glutathione reductase (GR) were higher in Pusa Jai Kisan than those in SS2. Contrarily, the activity of superoxide dismutase (SOD) was higher in SS2 than that in Pusa Jai Kisan and was the greatest at 25 umol L-1 Cd. Treatment of 25 umol L-1 Cd induced the maximum activity of enzymes. However, the activity of GR increased up to 50 umol L-1 Cd in both the cultivars. The non-enzymatic antioxidants ascorbate (AsA) and glutathione (GSH) were higher in Pusa Jai Kisan than that in SS2, whereas dehydroascorbate (DHA) and oxidized glutathione (GSSG) were higher in SS2. Photosynthesis and growth were adversely and maximally decreased by 50 umol L-1 Cd treatment in both the cultivars, but SS2 exhibited greater reductions. The protection of photosynthesis and growth and lesser reduction in Pusa Jai Kisan were associated with its capacity to restrict accumulation of Cd in leaves resulting in lower level of TBARS and H2O2 and electrolyte leakage. Moreover, Pusa Jai Kisan exhibited efficient antioxidant metabolism for removal of Cd-induced reactive oxygen species.  相似文献   
42.
This paper presents the first report of multiple anthelmintic resistance in the gastrointestinal nematodes of goats and its possible contributory factors in an irrigated area (Pakistan). A total of 18 privately owned Beetal goat flocks were selected in order to determine the anthelmintic resistance against commonly used anthelmintics. Forty to 48 animals from each flock were selected according to their weight and egg count. The three anthelmintics viz., oxfendazole, levamisole and ivermectin, were given to three groups at manufacturer’s recommended dose while one group was kept as untreated control. Anthelmintic resistance was determined through faecal egg count reduction and egg hatch tests while assessment of the contributory factors of anthelmintic resistance was measured through the rural participatory approach. Faecal egg count reduction test revealed high prevalence of anthelmintic resistance (83.3%) and it was either single (levamisole) or multiple (oxfendazole and levamisole). Egg hatch test confirmed the resistance against oxfendazole as detected with faecal egg count reduction test. None of the goat flocks was resistant to ivermectin. Copro-cultures revealed that Haemonchus contortus, Trichostrongylus colubriformis and Teladorsagia circumcincta were the most common species exhibiting resistance to levamisole and oxfendazole. Step-wise logistic regression of the data on worm control practices revealed significant role of under-dosing, low-protein diets, healthcare supervision by the traditional healers and mass treatments.  相似文献   
43.
Journal of Soils and Sediments - Molecular organic markers are an effective tool to detect the adverse effects of anthropogenic inputs in the aquatic environment. Linear alkylbenzenes (LABs) are...  相似文献   
44.
The study was conducted in Taftan rangeland in Sistan and Baluchestan, Iran, to study the effects of grazing exclusion on reclamation of vegetation cover and soil properties. After a comprehensive assessment of the vegetation types, plant sampling was carried out in sampling stands (50?×?50?m). In each stand, vegetation properties were measured using simple transect lines (50?m) method within quadrats (5?×?5?m), with a systematically randomized method. Soil sampling (75 samples) was performed along transects from the surface layer (0–30?cm). Results showed that livestock exclusion significantly affected community characteristics. The species richness (14.32), diversity (2.97), and plant cover (65.14%) showed their maximum level in the 15-year exclusion. The soil nutrient content increased during exclusion. Organic carbon (4.20%), total nitrogen (1.12%), available potassium (393.33?mg?kg?1), and available phosphorus content (17.13?mg?kg?1) attained significantly greater values under the long-term exclusion. The soil pH level (8.93) was significantly higher in the overgrazed site compared to the grazing exclusion sites. The soil electrical conductivity was statistically similar under the three treatments. The amounts of silt (63.40%) and clay (14%) were greater in the long-term exclusion compared with overgrazed rangeland. The long-term exclusion showed the lowest amount of sand (22.50%). These results imply that livestock exclusion plays an important role in vegetation restoration and soil conservation of degraded ecosystems in arid regions. We suggest that more studies are required to investigate the effect of livestock exclusion on ecosystem process in the arid rangeland regeneration.  相似文献   
45.
Protein isolates extracted from differently stabilized rice bran were analyzed to work out the food use potential. Bulk density remained higher for isolates obtained from heat stabilized bran, the treatments were found to have positive impact on the oil absorption properties, while the water absorption was slightly impaired owing to some possible configurational changes. Surface hydrophobicity and emulsion properties were improved with bran stabilization. Isolates exhibited better foaming properties owing to the flexible nature of protein molecules, with less intensive disulfide bonding, that were slightly affected by the stabilization treatment. Nitrogen solubility index followed a curved pattern with the least value near isoelectric point that showed an increasing trend toward basic pH, and parboiled protein isolates exhibited better gelling properties among the isolates.  相似文献   
46.
In the present investigation, the long-term effect of pulse crop inclusion in the maize-wheat rotation was assessed for the nutrient availability and soil-plant nutrient cycling under different nutrient management practices. Including pulses in the maize-wheat rotation improved soil organic carbon (SOC) and plant available macronutrients being higher in maize-wheat-mungbean rotation. Inclusion of mungbean to maize-wheat rotation enhanced the nitrogen (33.9%), phosphorus (46.4%), potassium (36.3%), and sulphur (55.5%) uptake in maize crop; likewise, alternate-year chickpea inclusion increased the uptake of these nutrients by 18.2, 19.1, 21.7, 32.1%, respectively. Inorganic fertilization maintained the positive annual balance of nitrogen, phosphorus, and zinc. By contrast, the nutrient balance under organic nutrient management was mostly negative. The magnitude of negative balance of potassium and sulphur was higher in inorganic than that of organic nutrient management. The low nutrient supply (particularly nitrogen) in organic fertilization largely inhibited the yield of cereal crops but not that of pulses. In view of this, the inclusion of pulses in the cereal-cereal systems could cause substantial improvement in soil fertility and sustainability in Indo-Gangetic plains. We infer that supply of nutrients like nitrogen and phosphorus in organic, and potassium and sulphur in recommended inorganic fertilization merit special attention.  相似文献   
47.
A tub experiment was conducted to assess the effect of exogenously applied trehalose (0, 10, and 20 mM) on various attributes of two rice cultivars (Bas-385 and Bas-2000) under salt stress (0, 50, 100, and 150 mM). Salinity decreased growth, gas exchange characteristics, shoot and root potassium (K+) ions, hydrogen peroxide (H2O2), total soluble proteins, activity of catalase (CAT), and yield attributes, while it increased chlorophyll contents, shoot and root sodium (Na+) and calcium (Ca2+), malondialdehyde (MDA), glycinebetain (GB), free proline, and peroxidase (POD) activity. Foliar-applied trehalose improved growth attributes, net photosynthetic rate, GB, total soluble proteins, superoxide dismutase (SOD) and yield. Yield was not obtained at 150 mM salt stress. The rice cultivar Bas-2000 showed better performance with respect to gas exchange attributes and activities of enzymatic antioxidants. Overall, varying levels of foliar-applied trehalose proved to be effective in ameliorating adverse effects of salt stress on rice.  相似文献   
48.
The current study aimed to evaluate the efficacy of selenium nanoparticles (SeNPs), combined or loaded with chitosan (COS), in broiler chickens reared under standard management protocols. The parameters under investigation were production performance, organ development, components of the intestinal barrier, and ileal microbial count. Two hundred and forty day-old chicks were raised in five groups, with each group containing eight replicates (n=6/replicate). The control group received a basal diet whereas the other four groups received basal diets supplemented with SeNPs (0.5 mg/kg), COS (200 mg/kg), SeNPs+COS (0.5 mg/kg SeNPs + 200 mg/kg COS), and SeNPs-loaded COS (SeNPs-L-COS) (200 mg/kg) respectively. On day 35, two birds/replicate were sampled to collect the viscera under investigation. The results revealed that dietary inclusion of SeNPs-L-COS increased (p<0.05) the body weight gain and improved (p<0.05) feed conversion ratio. Similarly, SeNPs-L-COS supplementation increased (p<0.05) the small intestinal villus surface area as well as the count of acidic goblet cells and intraepithelial lymphocytes when compared with the control group. Whereas the total goblet cell count was higher (p<0.05) in the small intestines of both the SeNPs+COS and SeNPs-L-COS groups. Microbial analysis of ileal contents also revealed an increase (p<0.05) in Lactobacilli species count with a concurrent decrease (p<0.05) in Escherichia coli count in the SeNPs-L-COS group when compared with the COS and control groups. Based on the results of the current trial, we can conclude that supplementation with SeNPs-L-COS is a superior combination for promoting the gut health and performance of broilers.  相似文献   
49.
Summary

The aim of this study was to evaluate the anti-oxidant activities of petroleum ether, methanol, ethyl acetate, and aqueous extracts of the aerial parts and inflorescences of the herb, Artemisia amygdalina Decne. Methanolic extracts of the aerial parts and aqueous extracts of the inflorescences gave the maximum levels of inhibition (90.6% and 76.4%, respectively) in the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay when compared to ascorbic acid, which showed 77.9% inhibition. The superoxide radical scavenging activity was highest in methanolic extracts of the aerial parts and in methanolic extracts of inflorescences (94.3% and 88.5%, respectively). These values were comparable to the reference standard, ascorbic acid, which showed 92.8% superoxide radical scavenging activity. In the deoxyribose assay, α-tocopherol showed 50.1% inhibition, while methanolic extracts of the aerial parts and inflorescences showed 46.2% and 46.4% inhibitory activity, respectively, against hydroxyl radicals. In the ferric thiocyanate assay, petroleum ether extracts of the aerial parts showed 78.7% inhibition, while ethyl acetate extracts of inflorescences showed 80.2% inhibition. The commercial standard, α-tocopherol, showed 79.7% scavenging activity. Extracts of A. amygdalina may provide an alternative source of natural anti-oxidant activity.  相似文献   
50.
Cotton jassid, Amrasca devastans (Distant), is an economically important pest of various crops (i.e. cotton, okra, brinjal) and has the potential to become resistant against insecticides due to the intense use of insecticides in the region which entails high selection pressure. To monitor the resistance levels against recently used new chemistry insecticides (nitenpyram, spirotetramat, chlorfenapyr, fipronil, emamectin benzoate, sulfoxaflor, and flonicamid), four field populations of A. devastans collected from Khanewal, Multan, Muzaffargarh and Lodhran districts were examined by leaf dip bioassays. The results revealed the 32.95–136.47 fold resistance to nitenpyram, 23.03–56.74 fold to spirotetramat, 10.84–31.33 fold to chlorfenapyr, 1.20–9.43 fold to fipronil, 3.27–43.77 fold to emamectin benzoate, 0.66–2.81 fold to sulfoxaflor and 0.59–1.25 fold to flonicamid in different field populations, compared to the susceptible strain. Based on present study findings, it may be suggested to discontinue the use of nitenpyram, spirotetramat, chlorfenapyr and emamectin benzoate for which the populations were resistant and the rotational use of fipronil, sulfoxaflor and flonicamid for which the populations were susceptible. Proactive resistance management approaches such as judicious use of insecticides with proper dose selection, time of spray on early stages and correct method of application are necessary to prevent the development of resistance.  相似文献   
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