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941.
Roghayeh Shahriaripour Ahmad Tajabadipour Isa Esfandiarpoor Vahid Mozafary 《Communications in Soil Science and Plant Analysis》2018,49(18):2284-2290
Phosphorus (P) fertilization is commonly based on soil testing, for which a variety of different soil P extraction methods are in use. In this research, the correlation and calibration of five extraction techniques for available P were studied: Soltanpour and Schwab, Olsen, EDTA-Na2, Paauw and Morgan in 168 different soil samples from 63000 ha of Sirjan pistachio orchards of Kerman province, Iran. The Morgan reagent extracted the most P and then EDTA-Na2> Olsen> Soltanpour and Schwab> Paauw extracted more phosphorus, respectively. Positive and significant correlation (P < 0.05) existed among all extractants. The correlation coefficients between different extractants and plant P concentration indicated that, EDTA-Na2 (P < 0.01), Olsen and Paauw methods (P < 0.05) had positive and significant correlation with leaf P concentration and thus with due attention to acceptable relationship with plant indices, the Olsen and EDTA-Na2 methods could be used to advise on available P. 相似文献
942.
943.
Ahmad Maryudi Ani A. Nawir Dewi A. Sekartaji Purnomo Sumardamto Ris H. Purwanto Ronggo Sadono Priyono Suryanto Emma Soraya Djoko Soeprijadi Agus Affianto Rohman Rohman Slamet Riyanto 《Small-Scale Forestry》2017,16(1):119-131
Smallholder timber plantations may offer opportunities for farmers to increase their income. Nonetheless, such opportunities are often lost largely due to unfavorable regulations imposed on harvesting and marketing of timber. Adverse impacts are worsened because the regulations are not effectively communicated to smallholder farmers. We assessed the level of smallholder knowledge of existing regulations and found it very low. In part, this correlated to their socio-demographic characteristics. Poor literacy skills and a low level of education make it difficult for older farmers’ to increase their knowledge. This is compounded by the limited information channels that can reach the farmers. Improving smallholders’ knowledge by providing information concerning markets and regulations in a timely and clear manner could help smallholders exercise coping strategies and priorities when selling their timber that would in turn reduce the negative impacts of regulations. The roles of village authorities could be crucial. They are close to the smallholders and could channel the information. The government could provide training and incentives for them to be more active in communicating the regulations to the smallholders. 相似文献
944.
Shreen Deeb Nusair Yousef Sa’id Abu Zarour Ahmad A. Altarifi 《Water, air, and soil pollution》2017,228(7):266
The polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) are persistent environmental pollutants. Recently, there have been an increasing demand to assess different biomarkers as early alarming indicators of environmental pollution. This study is the first to investigate the effects of PCDD/Fs on acetylcholinesterase (AChE) activity and histopathology of the body wall (epidermis, circular, and longitudinal muscles) of earthworm Eisenia andrei (Oligochaeta, Lumbricidae) using acute filter paper toxicity test. It is also exploring the selected biomarkers as a potential tool for evaluating soil quality. Earthworms were exposed to 0, 0.5, 1.0, and 1.5 ng/cm2 PCDD/Fs. The treated worms expressed progressive abnormal morphological signs with incrementing doses of dioxins, such as coiling, curling, and body swelling. At the highest dose, some worms demonstrated skin discoloration, loss of body segmentation, and body part detachment. The AChE activity was significantly decreased (p < 0.001) in all treated animals compared to control. The mixture induced circular muscle hyperplasia at 0.5 ng/cm2. However, the mixture at 1.5 ng/cm2 caused epidermal atrophy with cell pyknosis and necrosis in all layers of the body wall. Image analysis revealed significant reduction in the thickness of the epidermis (p < 0.001) at all doses with relative to control. Herein, we report that 48 h of acute exposure of E. andrei to dioxins/furans induced morphological changes, reduced the activity of AChE, and induced histopathological alterations. The outcomes can be utilized as endpoints that could be added to earthworm’s standardized short tests for ecotoxicity studies. 相似文献
945.
Javid Ahmad Bhat Biswapati Mandal Gora Chand Hazra 《Communications in Soil Science and Plant Analysis》2017,48(4):395-404
Twenty acid soils of West Bengal, India, representing Alfisols, Entisols and Inceptisols orders, were studied to characterize their acidity in relation to physicochemical properties. Total potential acidity (TPA), pH-dependent acidity (PDA), total acidity (TA), hydrolytic acidity (HA) and exchange acidity (EA) ranged from 2.02–6.90, 1.75–6.05, 1.18–2.75, 0.98–1.90 and 0.06–0.85 cmol(p+) kg?1, respectively. Relative order for all forms of acidity was: Entisols>Alfisols>Inceptisols. Average contribution of EA to TPA and TA was 9.7% and 19.7%, respectively, and that of PDA to TPA was 90.1%. Contribution of electrostatically bound H+ to EA was highest for Inceptisols followed by Entisols>Alfisols, and reverse was true for electrostatically bound aluminum (Al3+). All forms of acidity showed significant positive correlations with organic carbon (C) forms of Al but negative correlations with pH of soil. They also showed significant correlations with each other. Soil pH, organic C and exchangeable Al caused most of the variations in different forms of soil acidity. 相似文献
946.
Ahmad Khakwani Muhammad Imran Iftikhar Ahmad Rashid Waqas Sabir Hussain Sajid Mahmood Nadeem 《Communications in Soil Science and Plant Analysis》2017,48(1):73-82
This study was conducted to assess the efficacy of bio-organic phosphate (BOP) and diammonium phosphate (DAP) fertilizers for improving the growth, yield, plant phosphorus (P) content and profitability of wheat cultivation under systems of wheat intensification (direct seeding and nursery transplantation) and conventional sowing (broadcasting). BOP was formulated by enriching the compost with rock phosphate and inoculated with plant growth-promoting rhizobacterial (PGPR) strain, Bacillus thuringiensis strain K5. Results revealed the supremacy of BOP over DAP, and the direct seeding method over the other sowing methods in almost all parameters studied. The application of BOP significantly (p ≤ 0.05) increased the plant height, root length, number of tillers per plant, wheat biomass, number of grains per spike, 1000-grain weight, grain yield, straw and grain P contents in direct seeded wheat in comparison to DAP fertilization. Furthermore, application of BOP and direct seeding of wheat generated more profit per hectare compared with the other treatments. 相似文献
947.
Vermicompost can have an effective role in plant growth and nutrition. It can also reduce the harmful effects of stress caused by environmental factors. This study was a factorial experiment with a completely randomized plot design and three replications. The results showed that the calcium concentration (+40% +39%) of root and calcium (+71% +67%) and potassium contents (+49% +59%) of leaf under conditions of moderate and severe water stress increased under vermicompost treatments at the ratio of 30%. Sodium absorption (?37% ?21%) in moderate and severe conditions was significantly reduced by vermicompost treatment. In moderate and severe water stress, the growth medium of 30% vermicompost significantly enhanced proline (+39%) and soluble protein content (+28%) compared to the control. In conclusion, our results proved vermicompost fertilizer due to its structural properties and components, served to reduce the negative effects of water stress by increasing the absorption of calcium (Ca) and potassium (K), and decreasing sodium (Na) absorption that resulted in increased evaluations for proline and protein content. 相似文献
948.
Rajni Sinha U. S. Jaiswal M. Feza Ahmad Praveen Kumar Mishra Suparna Sinha 《Journal of plant nutrition》2017,40(13):1805-1815
Information about the nutritional status of a plant is a basic prerequisite for its adequate nutrition and is crucial to achieve high-yield productivity. Assessing the annual amount of nutrient that a tree needs to absorb in order to successfully complete a vegetative and reproductive growth is a fundamental step for developing rational fertilization in orchards. We are unaware of any report describing macro- and micronutrient dynamics in fruit at different growth stages of mango. Seven cultivars of mango (Dashehari, Langra, Mahmood Bahar, Menka, Sabri, Sundar Langra and Zardalu) were selected for the study. Different macronutrients such as nitrogen, phosphorus, potassium, calcium and magnesium (N,P, K, Ca, and Mg) and micronutrients such as iron, manganese, zinc and copper (Fe, Mn, Zn, and Cu) were analyzed at four growth stages, namelymarble stage, prestone formation stage, stone hardening stage and harvest stage. There was a significant variation in nutrient content of fruits throughout the developmental stages irrespective of cultivars. There was no definite trend of nutrient variation among cultivars but in general, most of the nutrients like N, P, K, Mg, Mn, Zn, and Cu were the highest at the marble stage, and Ca and Fe at the stone hardening stage. 相似文献
949.
冷季牦牛和黄牛采食行为、血清生化指标与瘤胃发酵参数的比较研究 总被引:1,自引:0,他引:1
本试验为研究冷季营养匮乏对放牧牦牛和黄牛血清生化指标、瘤胃发酵参数及放牧行为的影响,选取体重相近、健康无病的4岁母牦牛和母黄牛各10头,分别于2018年11月、2019年1和3月佩戴MOOnitor监测系统对其放牧行为进行研究.在试验期末(2019年3月)采集牧草样品、瘤胃液和血液,用于牧草营养成分、血清生化指标和瘤胃... 相似文献
950.
Mahroo Esmaeili Ali Rafe Seyed‐Ahmad Shahidi Azade Ghorbani Hasan‐Saraei 《Cereal Chemistry》2016,93(1):58-63
The functional properties of proteins from Tarom and Shiroodi cultivars were determined and compared with technological aspects of food and nutraceutical applications. Shiroodi has higher protein content than Tarom, and the yields of protein obtained were 72.88 and 66.36%, respectively. Nitrogen solubilities of rice bran protein of Tarom were more than Shiroodi at all pH levels. In addition, higher solubility was found in acidic or alkaline conditions. Although the rice bran proteins had lower emulsifying properties than bovine serum albumin, they had similar foaming properties in comparison with egg white. Tarom isolates had a significantly higher solubility, emulsifying property, and foaming stability and greater surface properties than Shiroodi isolates. The results showed the surface hydrophobicities of rice bran protein were greater than casein and ovalbumin and lower than other proteins such as bovine serum albumin. Water and oil absorption capacities were 1.03 and 1.66 for Tarom and 87.3 and 75.3 for Shiroodi, respectively. The bulk densities of Tarom and Shiroodi were also 0.55 and 0.53 g/mL, which make them suitable for weaning food and other industrial applications. As a result, these rice bran proteins showed higher hydrophobicity than that of other rice bran protein varieties as well as more functionality. Thus, they have good potential in the food and pharmaceutical industries. 相似文献