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111.
保护性耕作下西南旱三熟农田土壤水分动态及产量效应 总被引:1,自引:0,他引:1
以西南地区麦/玉/薯三熟制种植模式为研究对象,研究了不同保护性耕作模式下旱地土壤水分动态变化、水分利用效率、作物产量和经济效应。结果表明,不同保护性耕作对整个农田生态系统产量和水分利用效率具有显著影响。秸秆覆盖(TS)、地膜覆盖(TM)、秸秆覆盖+地膜覆盖(TSM)和垄作+秸秆覆盖+地膜覆盖(RSM)能改善7,10月份0—60cm土层土壤含水量及贮水量,而垄作(R)、垄作+秸秆覆盖(RS)和垄作+地膜覆盖(RM)的作用不明显。与平作(CK)相比,RSM,RM,RS,TSM,TM,TS和R分别使系统增产10.52%,6.11%,6.77%,4.59%,5.12%,3.15%,1.24%。这些处理对水分利用效率和降水利用效率的增幅分别为1.26%~11.08%,1.27%~10.57%。研究结果说明,从WUE、降水利用效率、产量效应、经济效益这4个方面来看,垄作+秸秆覆盖+地膜覆盖耕作模式综合效益最佳。 相似文献
112.
Bahador Bagheri Bahram Sohrabi Ali Akbar Movassaghpour Simin Mashayekhi Afagh Garjani Mehriar Shokri Masoud Pezeshkian Alireza Garjani 《Iranian Biomedical Journal》2014,18(2):76-81
Bacground: Evidence from several lines of investigations suggests that Toll-like receptor 4 (TLR4) is involved in atherosclerosis as a bridge between innate and acquired immunity. Percutaneous coronary intervention (PCI) can trigger inflammation through activation of human TLR4 (hTLR4) on monocytes. Hydrocortisone as an anti-inflammatory and immuno-suppressant agent has multiple mechanisms of action. In this study, we aimed at assessing the effects of hydrocortisone on monocyte expression and activity of hTLR4 in patients underwent PCI. Methods: Blood samples were taken from a total of 71 patients with chronic stable angina who were scheduled for a PCI, before the intervention. Thirty patients received 100 mg hydrocortisone prior to the procedure. Control group was composed of 41 patients underwent PCI without receiving hydrocortisone. Blood collection was repeated 2 and 4 h after PCI. The expression of hTLR4 on the surface of CD14+ monocytes and the serum levels of TNF-α and IL-1β were measured using flowcytometry and Sandwich ELISA. Results: Compared with controls, hydrocortisone significantly reduced monocyte expression of hTLR4 in test group (P<0.01). In addition, it had a significant effect on reduction of serum concentrations of TNF-α and IL-1β in test group in a time-dependent manner (P<0.01). Conclusion: In this study, hydrocortisone was able to reduce the hTLR4/CD14 positive monocytes and its related pro-inflammatory cytokines, thus it can decrease inflammatory responses following PCI. Key Words: Toll-like receptor 4, Cytokines, Hydrocortisone 相似文献
113.
Qumer Iqbal Muhammad Amjad Muhammad Rafique Asi Agustin Ariño 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(4):358-363
Studies were conducted to investigate the accumulation pattern of capsaicinoids and antioxidants such as carotenoids, ascorbic acid and phenolic compounds in three hot pepper hybrids at five different harvesting stages: immature green, mature green, color break, red ripe and dried fruit. Capsaicin and dihydrocapsaicin contents were maximum at mature green stage in both Sky Red (61.30 and 43.76 mg/100 g) and Wonder King (43.93 and 26.16 mg/100 g) hybrids, whereas Maha hybrid reached top values at color break stage (39.13 and 24.20 mg/100 g). The accumulation of total carotenoids showed an 8-fold increase from red ripe (12 mg/100 g) to dried fruit stage (96 mg/100 g), while a noticeable decline by 76 % was observed for ascorbic acid at same harvesting stages (150 vs. 36 mg/100 g, respectively). The three hot pepper hybrids showed great variations in the evolution of total phenolic contents during harvesting stages. Overall, the mature green stage was ideal to acquire maximum pungency due to capsaicinoids, while peppers at red ripe stage were best sources of ascorbic acid and dried fruits contained higher levels of total carotenoids. 相似文献
114.
Internal bond (IB) strength is one of the most important me-chanical properties that indicate particleboard quality. The aim of this study was to find a simple regression model that considers the most ... 相似文献
115.
Huawei Su Yachun Wang Qian Zhang Fuwei Wang Zhijun Cao Muhammad Aziz Ur Rahman Binghai Cao Shengli Li 《Tropical animal health and production》2013,45(7):1495-1503
Twenty multiparous Chinese Holstein dairy cows calving in hot summer (S group), were compared with 20 similar control cows calving in cool autumn (C group). Diets were the same for both groups; prepartum diets had relatively low energy density. Average temperature–humidity index was 76.5 and 53.0 in summer and autumn, respectively. S group cows had significantly higher rectal temperatures (39.6 vs. 39.0 °C) and respiration rates (79.0 vs. 31.3 breaths/min) than C group, and consumed less feed (prepartum 8.0 vs. 12.3 kg/day, postpartum 16.3 vs. 21.2 kg/day). Calculated energy balance (EB) was ?7.98 vs. ?5.15 Mcal/day for S group prepartum and postpartum, respectively. In contrast, EB was 1.36 vs. ?2.03 Mcal/day for C group prepartum and postpartum, respectively. S group produced significantly less milk than C group by 15.4 % (5.2 kg/day) and 26.8 % (10.2 kg/d) for milk yield and energy-corrected milk, respectively. Percentages of milk fat (3.28 vs. 4.29 %), protein (3.08 vs. 3.33 %), and solids-not-fat (8.46 vs. 8.78 %) were significantly lower for S group. Milk urea nitrogen (19.54 vs. 13.31 mg/dL) was significantly higher in S group. Significantly lower feed efficiency was observed in S group (1.56 vs. 1.66). During the entire transition period, S group had significantly lower circulating glucose levels. S group had significantly higher levels of nonesterified fatty acids (NEFA) prepartum, but after 14 days in milk, NEFA was significantly lower. We conclude that increasing dietary energy density during transition period (especially prepartum) is necessary to minimize adverse effects of hot season. 相似文献
116.
1. A study was designed to investigate the comparative effect of supplementary vitamin E, vitamin C, probiotics and dietary crude protein concentration on semen traits and seminal plasma biochemical parameters in male broiler breeders after Zn-induced moulting. 2. A total of 180 male broiler breeders were induced to moult at 65 weeks of age by mixing ZnO in diet at the rate 3000?mg/kg of feed. After moulting, the males were divided into six groups that were given feed supplemented with: vitamin C (500?IU/kg), vitamin E (100?IU/kg), protein (140?g CP/kg), probiotics (50?mg/kg) and the combination of these components, while one group was kept as a control. Semen samples were collected weekly and semen volume, spermatozoa concentration, motility and dead spermatozoa percentage were determined. Seminal plasma was separated to determine the concentration of total antioxidant capacity (TAC), homocysteine, paraoxonase (PON1), arylesterase, ceruloplasmin, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities. 3. Semen volume was significantly higher in the vitamin E and C groups compared to the control. Spermatozoa motility was higher in the vitamin E group and dead spermatozoa percentage was significantly lower in the vitamin C group compared with the control group. 4. Seminal plasma TAC was higher in the vitamin E group, homocysteine was lower in the vitamin C and E groups. PON1 was higher in the combination group. Arylesterase increased significantly in the vitamin C and combination groups over time. Seminal plasma AST was significantly lower in the vitamin C and E supplemented groups whereas ALT decreased significantly only in the vitamin E group compared with the control. Higher concentrations of ceruloplasmin were observed in the combination group compared with the other treatments. 5. It was concluded that additional vitamin E and C or their combination was the most potent nutrient treatment for improving the semen traits and seminal plasma biochemical characteristics in male broiler breeders after Zn-induced moulting. 相似文献
117.
Muhammad MUSHTAQ Iftikhar HUSSAIN Afsar MIAN Shahid MUNIR Irfan AHMED Abdul Aziz KHAN 《Integrative zoology》2013,8(3):285-292
This research study evaluated the effect of different additives on the bait consumption by Indian crested porcupine, a serious forest and agricultural pest, under field conditions. Different additives (saccharin, common salt, bone meal, fish meal, peanut butter, egg yolk, egg shell powder, yeast powder, mineral oil and coconut oil) at 2 and 5% each were tested for their relative preference, using groundnut–maize (1:1) as basic bait. All the additives were tested under a no‐choice test pattern. For control tests, no additive was mixed with the basic bait. Saccharin at 5% concentration significantly enhanced the consumption of bait over the basic bait, while 2% saccharin supplemented bait resulted in a non‐significant bait consumption. All other additives did not enhance the consumption of the bait material; rather, these worked as repellents. However, the repellency was lowest with the common salt, followed by egg yolk, egg shell powder, bone meal, peanut butter, mineral oil, fish meal and yeast powder, while coconut remained the most repellent compound. The present study suggested that groundnut–maize (1:1) supplemented with 5% saccharin was the preferred bait combination, and can be used with different rodenticides for the management of Indian crested porcupine. 相似文献
118.
Muhammad Ashraf Muhammad Afzal Rashid Ahmad Muhammad A. Maqsood Sher M. Shahzad Mukkram A. Tahir 《Archives of Agronomy and Soil Science》2013,59(4):385-398
Adequate regulation of mineral nutrients plays a fundamental role in sustaining crop productivity and quality under salt stress. We investigated the ameliorative role of potassium (K as K2SO4) in overcoming the detrimental effects of sodium chloride (NaCl) on sugarcane genotypes differing in salt tolerance. Four levels of NaCl (0, 100, 130 and 160 mM) were imposed in triplicate on plants grown in gravel by supplying 0 and 3 mM K. The results revealed that application of NaCl significantly (p ≤ 0.05) increased sodium (Na+) but decreased K+ concentrations in shoots and roots of both genotypes with a resultant decrease in K+/Na+ ratios. Physical growth parameters and juice quality were also markedly reduced with increasing NaCl concentrations compared with controls. However, addition of K alleviated the deleterious effects of NaCl and improved plant growth under salt stress. Cane yield and yield attributes of both genotypes were significantly (p ≤ 0.05) higher where K was added. Juice quality was also significantly (p ≤ 0.05) improved with the application of K at various NaCl levels. The results suggested that added K interfered with Na+, reduced its uptake and accumulation in plant tissues and consequently improved plant growth and juice quality in sugarcane. 相似文献
119.
Feng-lian LÜ Miao-miao HOU Hong-tao ZHANG Asif Khan Muhammad Ayaz Ciren QIANGJIU Chang-lu HU Xue-yun YANG Ben-hua SUN Shu-lan ZHANG 《农业科学学报》2019,18(1):169-178
A high crop yield with the minimum possible cost to the environment is generally desirable. However, the complicated relationships among crop production, nitrogen (N) use efficiency and environmental impacts must be clearly assessed. We conducted a series of on-farm N application rate experiments to establish the linkage between crop yield and N2O emissions in the Guanzhong Plain in Northwest China. We also examined crop yield, partial factor productivity of applied N (PFPN) and reactive N (Nr) losses through a survey of 1 529 and 1 497 smallholder farms that grow wheat and maize, respectively, in the region. The optimum N rates were 175 and 214 kg ha–1 for winter wheat and summer maize, respectively, thereby achieving the yields of 6 799 and 7 518 kg ha–1, correspondingly, with low N2O emissions based on on-farm N rate experiments. Among the smallholder farms, the average N application rates were 215 and 294 kg ha–1 season–1, thus producing 6 490 and 6 220 kg ha–1 of wheat and maize, respectively. The corresponding PFPN values for the two crops were 36.8 and 21.2 kg N kg–1, and the total N2O emissions were 1.50 and 3.88 kg ha–1, respectively. High N balance, large Nr losses and elevated N2O emissions could be explained by the overdoses of N application and low grain yields under the current farming practice. The crop yields, N application rates, PFPN and total N2O for wheat and maize were 18 and 24% higher, 42 and 37% less, 75 and 116% higher, and 42 and 47% less, correspondingly, in the high-yield and high-PFPN group than in the average smallholder farms. In conclusion, closing the PFPN gap between the current average and the value for the high-yield and high-PFPN group would increase crop production and reduce Nr losses or the total N2O emissions for the investigated cropping system in Northwest China. 相似文献
120.
Muhammad Nurfaiz Abd Kharim Aimrun Wayayok Abdul Rashid Mohamed Shariff Ahmad Fikri Abdullah 《Communications in Soil Science and Plant Analysis》2019,50(5):639-649
Knowing actual nutrient requirements for rice plants is crucial in supplying the correct amount of fertilizer, especially nitrogen since nitrogen is one of the most key limiting nutrients in rice cultivation. A preliminary study of variable rate application (VRA) on System of Rice Intensification (SRI) planting by using organic foliar fertilizer was carried out to determine the effectiveness of precision fertilization. Foliar fertilizer was formulated based on actual nitrogen needed by rice plants using Soil-Plant Analyses Development (SPAD) chlorophyll meter measurements. The experiment was laid out in a randomized complete block design (RCBD) with four treatments (50% fixed rate, 100% fixed rate, 150% fixed rate and VRA) and four replications for each treatment. Plant growth performances (plant heights, number of tillers, number of panicle and flower) and yield performances (grain yield, number of grain, 1000-grain weight and number of spikelets) were recorded during the study. The results showed that foliar application of VRA resulted in significantly higher yield performances; grain yield (13.65 g), number of grain (807.50), 1000-grain weight (16.79 g), and number of spikelets (7.50) compared to uniform fertilizer applications. VRA treatments had the highest SPAD readings at every planting stage during the experiment; however, a high nitrogen supply was needed during the mid-tillering stages (35 DAT) compared to other fertilizer rates. Besides, VRA application shows the most savings in term of total nitrogen supply (415 µg) compared to uniform rates application; 50% fixed rate (400 µg), 100% fixed rate (810 µg), and 150% fixed rate (1210 µg). 相似文献