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101.
Mountain ecosystems are fragile and sensitive to changes. The past few decades have witnessed substantial changes in every aspect of the bio-physical and socio-cultural environment of the northern mountainous belt of Pakistan. Population growth and the associated household dynamics accompanied by agricultural and economic transformations and improvements in transportation network have initiated and accelerated unprecedented changes in the bio-physical setup particularly land use patterns and distribution of natural resources. Forests resources are one of the most important natural assets of this region and several communities in remote mountainous areas of the region still depend on these resources for subsistence. The present study aims to explore the changes occurring in the socio-economic environment particularly population growth and household dynamics and their impacts on forest cover and diversity of the Hindu Raj Mountains of northern Pakistan. The study relies on remote sensing and GIS technology for characterizing forest cover dynamics and questionnaire data for household changes. Findings reveal that significant changes have occurred in the basic household characteristics and population changes are resulting in a high rate of deforestation in the study area.  相似文献   
102.
Gladiolus corms were grown in media contaminated with cadmium (Cd) (50 mg kg?1) and supplemented with silicon (Si) and potassium (K). The role of Si and K for mitigation of Cd toxicity was evaluated. Cd-induced stress generated significantly increased level of oxidative stress markers including hydrogen peroxide (H2O2), and malondialdehyde (MDA) in gladiolus. The application of K and Si improved the production of protein and proline in the treated plants. Moreover, K and Si supplemented plants exhibited an improvement in the activity of antioxidant enzymes and a reduction in the level of MDA, H2O2 and Cd uptake under Cd stress. Application of K and Si also enhanced the uptake of mineral nutrients including calcium (Ca), magnesium (Mg), manganese (Mn), sulfur (S) and K. The plants supplemented with K and Si exhibited a higher amount of total phenolics and flavonoids. The combined effect of Si and K was more pronounced regarding beneficial effects on gladiolus plants compared to individual effect of these elements under Cd stress. The current research reveals that Si and K may improve gladiolus growth by decreasing the oxidative stress and Cd uptake and by increasing the activity of antioxidant defense enzymes, the quantity of secondary metabolites and plant nutrition.  相似文献   
103.
To evaluate the effects of different irrigation and nutrient concentration strategy on growth, yield, water use efficiency (WUE), fruit quality and substrate salt accumulation, tomatoes were grown with five different levels of water (W: 50%, 75%, 100%, 125% and 150%) and nutrient concentrations (N: 0.5, 0.75, 1.0, 1.5 and 2.0 times of Hoagland strength(X)). Fruit quality index was determined by normalization of fruit quality parameters. Deficit irrigation at standard concentration of nutrients reduced yields by 17.43% and 15.52% for T7 (W75%-N1.0x) and 49.54%–51.99% for T8 (W50%-N1.0x) during spring-summer (SS) and fall-winter (FW) seasons, respectively. Contents of total soluble solids (TSS), titrable acidity (TA) and sugar acid ratio (SAR) were all increased in water-deficit treatments. T8 was found to be highest in TSS, TA and SAR except SAR in FW. Over-irrigation with excessive and standard Hoagland nutrient concentration caused non-significant reduction in yield except T6 (W125%-N1.0x) in SS. T2 (W100%-N2.0x) and T4 (W100%-N1.5x) caused more substrate salt accumulation which resulted in significant decrease in yield and WUE. Through economic analysis, over-watering along with excessive nutrients caused profit reductions. Considering water saving, yield and fruit quality through economic analysis, T7 found to be optimal strategy.  相似文献   
104.
The effect of total mixed ratios containing wheat middlings (WM) as a corn grain substitute on the growth performance and carcass traits of Comisana ewe lambs was evaluated. Forty ewe lambs, with average live body weight of 13 ± 0.3 kg (mean ± SEM), were allocated randomly to two isocaloric and isonitrogenous diets for 50 days. Control diet contained 400 g/kg of dry matter (DM) of corn as the main starchy source, whereas experimental diet contained 600 g/kg DM of WM. In vivo nutrient apparent digestibility of the two diets was determined using Comisana rams (mean body weight, 65 ± 2.3 kg) and indicated significant (P < 0.05) differences for neutral detergent fibre, acid detergent fibre, cellulose and hemicellulose fractions. Results from the trial using Comisana ewe lambs showed that growth traits were unaffected by dietary treatments as well as none of the carcass measurements examined (P > 0.05). These findings indicate that WM results as a suitable feed ingredient for growing ewe lambs that can be a satisfactory substitute to conventional grain source.  相似文献   
105.
Besides being an essential macronutrient for plant growth, potassium (K) also acts as a stress-relieving agent against various biotic and abiotic stresses, especially water stress. An experiment consisting of three lowland Thai rice varieties (Pathumthani 1, RD57, RD41), two cultivation methods [dry direct seeding (DDS), transplanting (TP)] and four K doses (0, 80, 120,160?kg ha?1) under alternate wetting and drying (AWD) water regime was conducted to investigate the impact of K and cultivation method on lowland rice varieties subjected to AWD. Pathumthani 1 had significantly higher grain yield at the 120?kg K ha?1 compared with all other K doses. RD57 and RD41 had maximum grain yield at the 80 and 120?kg K ha?1, respectively, which was significantly higher than the control; however, grain yield among different K doses was mostly similar for RD57 and RD41. K application at the rate of 120?kg ha?1 for Pathumthani 1 and 80?kg ha?1 for RD57 and RD41 could be a feasible option. The performance of DDS and TP was better at the 80 and 120?kg K ha?1, respectively. Application of K at the optimum dose with proper selection of variety and cultivation method could help in sustainable rice production.  相似文献   
106.
107.
This experiment was conducted to assess nutritional potential of corn steep liquor (CSL) as an alternative protein source in broiler's diet. A total of 280‐day‐old unsexed broiler chicks were randomly distributed into four experimental groups in a simple randomised experimental design (each group had seven replicates; 10 birds per each). Four iso‐nitrogenous and iso‐caloric broiler starter and finisher diets (C, LCSL, MCSL and HCSL) were formulated containing 0%, 5%, 10% and 15% CSL respectively. Results revealed that chicks fed MCSL diet had significantly (p ≤ .05) the heaviest Body weight, highest Body weight gain and the lowest feed conversion ratio followed by those fed HCSL diet. In the starter period, LCSL and MCSL diets resulted in better (p ≤ .05) dry matter (DM) (89.57%) and crude protein (67.67%) digestibilities respectively. In the finisher period, DM, crude fibre and fat digestibilities were not affected by CSL inclusion levels; while crude protein digestibility was significantly (p ≤ .05) high in the groups fed LCSL and HCSL diets. The CSL inclusion had no effect on blood haematology except serum uric acid, which tended to increase with increasing CSL levels. No microscopic changes were exhibited on liver, heart, kidneys and intestine of birds across all dietary treatments. However, crops in birds fed HCSL diet showed moderate to severe hypertrophy and hyperplasia of the mucosal lining. The study showed that CSL could be added up to 15% in broiler's diet without any adverse effect on bird's performance.  相似文献   
108.
Melatonin and its receptors play a crucial role in the regulation of the animal reproductive process, primarily in follicular development. However, the role that melatonin performs in regulating hormones related with reproduction remains unclear. Melatonin and its receptors are present both in female and male animals’ organs, such as ovaries, heart, brain and liver. Melatonin regulates ovarian actions and is a key mediator of reproductive actions. Melatonin has numerous effects on animal reproduction, such as protection of gametes and embryos, response to clock genes, immune‐neuroendocrine, reconciliation of seasonal variations in immune function, and silence or blockage of genes. The growth ratio of reproductive illnesses in animals has raised a remarkable concern for the government, animal caretakers and farm managers. In order to resolve this challenging issue, it is very necessary to conduct state‐of‐the‐art research on melatonin and its receptors because melatonin has considerable physiognomies. This review article presents a current contemporary research conducted by numerous researchers from the entire world on the role of melatonin and its receptors in animal reproduction, from the year 1985 to the year 2017. Furthermore, this review shows scientific research challenges related to melatonin receptors and their explanations based on the findings of 172 numerous research articles, and also represents significant proficiencies of melatonin in order to show enthusiastic study direction for animal reproduction researchers.  相似文献   
109.
The present study was designed to study the effect of traditional antibiotic combination (streptomycin and penicillin; SP) and relatively modern combination of antibiotics (gentamycin, tylosin, lincomycin and spectinomycin; GTLS) in extender on bacterial control and spermatozoal quality of liquid buffalo bull semen stored at 5°C. Semen collected from Nili‐Ravi buffalo bulls (n = 10) was diluted with skim milk extender containing either SP (streptomycin 1000 μg/ml and penicillin 1000 IU/ml), GTLS (gentamycin 500 μg/ml, tylosin 100 μg/ml, lincomycin 300 μg/ml and spectinomycin 600 μg/ml) or negative control with no antibiotics (NA). Liquid semen was stored at 5°C for 5 days. Aerobic bacteria isolated from buffalo semen were Pseudomonas aeruginosa and Staphylococcus aureus. The only facultative anaerobic bacterium isolated was Klebsiella pneumoniae. In vitro antibiotic sensitivity test revealed that Ps. aeruginosa and Staph. aureus were susceptible to gentamycin. Staphylococcus aureus and K. pneumoniae were susceptible to tylosin and linco‐spectinomycin. Total aerobic bacterial count was significantly lower in semen samples treated with GTLS than those of SP on third and fifth day of storage at 5°C. There was no difference (p > 0.05) in sperm motility, longevity and plasma membrane integrity (PMI) in extender containing SP or GTLS combination until the third day of storage at 5°C. On fifth day of storage sperm motility, longevity and PMI was significantly better in extender containing SP compared with GTLS and NA. Intact acrosomes, and sperm head, mid piece and tail abnormalities remained similar (p > 0.05) because of antibiotics up to 5 days of storage. In conclusion, GTLS is more capable than SP for bacterial control of buffalo bull semen. Moreover, GTLS and SP are equally efficient in preserving spermatozoal quality of extended buffalo bull semen for 3 days at 5°C.  相似文献   
110.
This study was designed to observe physiological indices of a spring maize response with the integration of beneficial microorganism, organic and inorganic nitrogen (N) fertilizer, and N levels. Field experiments were conducted in three replications during 2014 and 2015 at Agronomy Research Farm, the University of Agriculture Peshawar, Pakistan. Different beneficial microbes (BM) (with BM and without BM), organic (farm yard manure, FYM) and inorganic (ammonium nitrate) N ratios (0:100, 25:75, 50:50, 75:25, and 100:0), and nitrogen levels (N) (100, 150, and 200 kg ha?1). Beneficial microorganism, 50:50 ratio of organic and inorganic N, and 200 kg N ha?1 seem better in terms of improving SPAD value, plant height (cm), leaf rea (cm2), and leaf area index (LAI) of spring maize. Therefore, the application of BM, 50:50 ratio of organic and inorganic N, and 200 kg N ha?1 were recommended for enhancing crop physiology in agro-climatic condition for Peshawar, Pakistan.  相似文献   
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