Pakistan Academy of science

Islamabad, Pakistan

Pakistan Academy of science

Islamabad, Pakistan

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Ryan J.,International Center for Agricultural Research in the Dry Areas | Ibrikci H.,Cukurova University | Delgado A.,University of Seville | Torrent J.,University of Cordoba, Spain | And 2 more authors.
Advances in Agronomy | Year: 2012

Fertilizers have been largely responsible for the massive increases in world food production in the past half century that permitted accelerated global population growth to current unprecedented levels. Fertilizer use not only impacts crop yields but also affects animal production. While nitrogen (N) has been the main driver of such changes, phosphorus (P) also has a major role. Like N, the use of P fertilizers can have implications beyond the farmers' fields, if excessive amounts are applied. The past four decades have witnessed overuse of P fertilizers as well as animal manures in the intensive agricultures of some European countries and North America. Yet ironically in many areas of the world, notably Africa, agricultural output is largely constrained by low soil P in combination with little or no P fertilizer application. Rock phosphate is the global source of the raw material for P fertilizer. However, resources are finite, and therefore efficient and wise use is of paramount importance. The vast West Asia and North Africa (WANA) region is one where agricultural output is beset with major environmental constraints. Yet fertilizer use in the region is still in the incipient to early development stage, ironically in view of the fact that major deposits of exploitable rock phosphate are found in the region, mainly in Morocco and Tunisia. With the predominantly calcareous soils of the region being inherently low in available P, the main focus in the past few decades has been on promoting P use and its efficient management in rainfed and irrigated agriculture. In the 1960s and 1970s, virtually no fertilizer was used in the region, with rapid increases in N and to a lesser extent P since then. The sharp transition from low-input traditional agriculture to conventional modern agriculture has particular implications for efficient P fertilizer use from the economic and environmental standpoints. This review seeks to present a broad overview of P in countries of the WANA region, which varies considerably with respect to economic development and the level of agricultural research, education and extension. It presents the background global considerations with respect to P supplies and use, as well the agricultural context for the region, including climate and cropping systems; it draws heavily on research on soils and soil-P chemistry from Spain, which though technically excluded from WANA, has much in common with the Mediterranean region, and highlights P research from Pakistan at the eastern fringes of WANA. It highlights the discrepancy in P use between developed and developing countries such as those of WANA. The review to some extent builds on extensive research carried out in Syria by the International Center for Agricultural Research in the Dry Areas (ICARDA), with secondary emphasis on countries of the region, many of which collaborate closely with ICARDA. The review covers the past three decades, highlighting progress in field trials on fertilizer use with the region's main crops in relation to rainfall, cropping systems, soil test levels, and efforts to identify P-efficient genotypes and enhance soil P fertility with mycorrhizae. Despite the many isolated, uncoordinated, and often-overlapping, and indeed conflicting, research efforts that have taken place in the region, we have attempted to show a gradual progression in knowledge of P in relation to soils and crops. Developments with regard to P, in the overall framework of agricultural research, have contributed to increased output in the WANA region. Much of the documented research has contributed to the global information on soils of arid and semi-arid regions. Despite achievements in applied research, poorly developed technology transfer systems and weak analytical facilities remain as stumbling blocks to the widespread dissemination of the accumulated knowledge on P use to farmers. © 2012 Elsevier Inc.

Zou C.Q.,Key Laboratory of Plant Soil Interaction | Zhang Y.Q.,Key Laboratory of Plant Soil Interaction | Rashid A.,Pakistan Academy of science | Ram H.,Punjab Agricultural University | And 16 more authors.
Plant and Soil | Year: 2012

Aim: Zinc (Zn) fertilization is an effective agronomic tool for Zn biofortification of wheat for overcoming human Zn deficiency. But it still needs to be evaluated across locations with different management practices and wheat cultivars, since grain Zn concentrations may be significantly affected by locations, cultivars and management. Materials: Field experiments were conducted over 3 years with the following four Zn treatments: nil Zn, soil Zn application, foliar Zn application and soil + foliar Zn application to explore the impact of Zn fertilization in Zn biofortification of wheat. The experiments were conducted at a total of 23 experimental site-years in China, India, Kazakhstan, Mexico, Pakistan, Turkey and Zambia. Results: The results showed that foliar Zn application alone or in combination with soil application, significantly increased grain Zn concentrations from 27 mg kg-1 at nil Zn to 48 and 49 mg kg-1 across all of 23 site-years, resulting in increases in grain Zn by 84 % and 90 %, respectively. Overall, soil Zn deficiency was not a growth limiting factor on the experimental sites. A significant grain yield increase in response to soil Zn fertilization was found only in Pakistan. When all locations and cropping years are combined, soil Zn fertilization resulted in about 5 % increase in grain yield. Foliar Zn application did not cause any adverse effect on grain yield, even slightly improved the yield. Across the 23 site-years, soil Zn application had a small effect on Zn concentration of leaves collected before foliar Zn application, and increased grain Zn concentration only by 12 %. The correlation between grain yield and the effectiveness of foliar Zn application on grain Zn was condition dependent, and was positive and significant at certain conditions. Conclusion: Foliar Zn application resulted in successful biofortification of wheat grain with Zn without causing yield loss. This effect of Zn fertilization occurred irrespective of the soil and environmental conditions, management practices applied and cultivars used in 23 site-years. Foliar Zn fertilizer approach can be locally adopted for increasing dietary Zn intake and fighting human Zn deficiency in rural areas. © 2012 Springer Science+Business Media B.V.

Haque Q.,Pakistan Institute of Nuclear Science and Technology | Haque Q.,Pakistan Academy of science | Saleem H.,Pakistan Academy of science | Saleem H.,Institute of Space Technology
Physics of Plasmas | Year: 2015

The plasma density non-uniformity gives rise to the coupling of transverse magnetic electron drift vortex (MEDV) mode with the longitudinal perturbations in dissipative and non-dissipative electron plasmas. This coupling produces partially transverse and partially longitudinal low frequency instabilities in classical un-magnetized laser plasmas. The MEDV mode couples with the ion acoustic wave, when the ion dynamics is also included. Both the modes have frequencies of the same order of magnitude and couple to give rise to electromagnetic instabilities in un-magnetized plasmas. © 2015 AIP Publishing LLC.

Afzal I.,Quaid-i-Azam University | Shinwari Z.K.,Pakistan Academy of science | Iqrar I.,Quaid-i-Azam University
Pakistan Journal of Botany | Year: 2015

Endophytic bacteria can provide a useful alternative to synthetic fertilizers to improve plant growth. Wild plants are little investigated as a source of growth promoting endophytic bacteria for commercial application to crops. In present study, endophytic bacteria were isolated from Cannabis sativa L. (hemp) using two different methods to examine their ability to promote canola growth. Besides direct isolation from the roots, endophytic bacteria were also selectively isolated from the rhizosphere of C. sativa using canola. Under gnotobiotic conditions, six bacteria from the selective isolation significantly improved canola root growth, as compared to the two bacteria isolated from direct method. Overall, three isolates performed distinctly well, namely, Pantoea vagans MOSEL-t13, Pseudomonas geniculata MOSEL-tnc1, and Serratia marcescens MOSEL-w2. These bacteria tolerated high salt concentrations and promoted canola growth under salt stress. Further, the isolated bacteria possessed plant growth promoting traits like IAA production, phosphate solubilization, and siderophore production. Most isolates produced plant cell-wall degrading enzymes, cellulase and pectinase. Some isolates were also effective in hindering the growth of two phytopathogenic fungi in dual culture assay, and displayed chitinase and protease activity. Paenibacillus sp. MOSEL-w13 displayed the greatest antifungal activity among all the isolates. Present findings conclude that wild plants can be a good source for isolating beneficial microbes, and validates the employed selective isolation for improved isolation of plant-beneficial endophytic bacteria. © 2015, Pakistan Botanical Society. All rights reserved.

Alam K.,University of PeshawarKhyber Pakhtunkhwa | Shaheen K.,University of Peshawar | Blaschke T.,University of Salzburg | Chishtie F.,Pakistan Academy of science | And 2 more authors.
Aerosol and Air Quality Research | Year: 2016

The present study investigates various types of aerosol in the Lahore city of Pakistan using Aerosol Robotic Network (AERONET) data over a six year period from 2007 to 2012. Aerosol optical depths (AODs) observed was in the range 0.2–1.12. An analysis of seasonal variations in AOD has indicated that the highest AOD values occurred in summer and the lowest in winter. The urban aerosols of the study area were classified on the basis of optical parameters such as AOD, Extinction Angstrom Exponent (EAE), Absorption Angstrom Exponent (AAE), Single Scattering Albedo (SSA), Asymmetry Parameter (ASY) and Refractive Index (RI). The AAE values were in the range from 0.25 to 3.2. Real Refractive Index (RRI) and Imaginary part of the Refractive Index (IRI) values were in the range from 1.5 to 1.6 and 0 to 0.005 respectively. The major contributions to the atmospheric aerosols over Lahore were from urban industrial emissions, fossil fuel burning and road/soil dust. Higher RRI values reflected larger re-suspended road dust particles and long-range transported particles, while lower values reflected increased anthropogenic absorbing carbonaceous aerosols over the area. The AERONET retrieved SSA (0.80–0.89) and ASY (0.70–0.83) values suggested a predominance of urban industrial, vehicular and dust aerosols over Lahore. The Derivative of Angstrom Exponent (DAE) was derived at a wavelength of 500 nm and was found to indicate a predominance of fine aerosols across all seasons, particularly during summer and autumn seasons. Back-trajectory analyses using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model revealed that the major air masses over Lahore originated from India, Iran and Afghanistan. © Taiwan Association for Aerosol Research.

Hashmi A.H.,Institute of Biomedical and Genetic Engineering | Ahmad N.,Institute of Biomedical and Genetic Engineering | Riaz S.,Institute of Biomedical and Genetic Engineering | Ali L.,Institute of Biomedical and Genetic Engineering | And 4 more authors.
Genes and Immunity | Year: 2014

Recent discovery of single-nucleotide polymorphisms located in the upstream region of interleukin-28B (IL28B) has shown association with interferon (IFN) treatment response especially in hepatitis C virus (HCV) genotype 1-infected patients. Pakistan, being the country with second highest prevalence of HCV with predominantly 3a genotype infection, bears a significant disease burden. The present study was conducted to evaluate the effect of rs12979860 genotypes on treatment response in HCV-3a-infected patients. This study shows that the CC genotype is providing protection against infection to HCV. But once infected, the CC genotype patients show viral persistence following IFN therapy. The TT genotype is assisting the 3a patients in viral clearance after IFN treatment. To our knowledge, this is the first study showing rs12979860 genotype association with IFN response in Pakistani HCV-3a-infected patients. © 2014 Macmillan Publishers Limited.

Zahra N.B.,Quaid-i-Azam University | Shinwari Z.K.,Quaid-i-Azam University | Shinwari Z.K.,Pakistan Academy of science | Qaiser M.,University of Karachi
Pakistan Journal of Botany | Year: 2015

The use of herbs for therapeutic purpose is as old as human history. In Pakistan a major part of population is dependent on the traditional medicine derived from plants for primary health care system. The interest in the use of traditional system of medicine has gained popularity globally. The developed countries are shifting their focus to further research based on the indigenous knowledge collected from aboriginal people. The present study reviews the ethno-medicinal uses of family Apiaceae reported from Pakistan. Out of 167 species reported from Pakistan, 66 are found to be used medicinally. Most commonly treated disorders by use of Apiaceae herbal flora are gastrointestinal tract and liver disorders (28%) followed by cough, cold and respiratory tract problems (11%). The plant parts frequently used are roots (22%) followed by whole plant material (19%), leaf material (18%), fruit (13%), seed (12%), stem, flower, aerial parts (5%) and sap (1%). It is suggested to carry out similar studies for other families to explore the indigenous knowledge for the development of commercial products and to collectively document the scattered existing knowledge. © 2015, Pakistan Botanical Society. All rights reserved.

Jan S.A.,Quaid-i-Azam University | Shinwari Z.K.,Quaid-i-Azam University | Shinwari Z.K.,Pakistan Academy of science | Rabbani M.A.,Pakistan National Agricultural Research Center
Pakistan Journal of Botany | Year: 2016

Salt stress is one of the major abiotic stresses that affect normal morpho-physiological and biochemical processes of Brassica rapa. In present study the effect of salt stress on three important ecotypes of B. rapa (brown sarson, yellow sarson and Toria) was studied. The plants were regenerated at four NaCl levels (0, 50,100 and 150 mmol). The effect of salt stress on shoot length, root length, shoot fresh and dry weight, root fresh and dry weight, leaf relative water content (RWC), proline and chlorophyll a, b, a+b contents were recorded. The high salt stress significantly decreased the shoot length, root length, shoot fresh weight, shoot dry weight, and root fresh weight and root dry weight of all three ecotypes. The genotype 25007 (brown sarson) showed better morphological performance followed by Toria as compared to other genotypes. The RWC values and chlorophyll a, b and a+b contents were decreased up to several fold at high salt levels (50,100 and 150 mmol), while proline contents increased at these concentrations. Maximum RWC values and proline contents were recorded in genotype 25007 followed by Toria. The chlorophyll a, b and a+b amounts were higher in Toria followed by 25007 respectively. The brown sarson and Toria ecotypes showed better performance at high salinity levels as compared to yellow sarson. The resulted screened salt tolerant genotypes will be useful for salt affected area. © 2016, Pakistan Botanical Society. All rights reserved.

Rafique E.,Pakistan National Agricultural Research Center | Rashid A.,Pakistan National Agricultural Research Center | Rashid A.,Pakistan Academy of science | Mahmood-ul-Hassan M.,Pakistan National Agricultural Research Center
Plant and Soil | Year: 2012

Aims: The cotton (Gossypium hirsutum L.)-wheat (Triticum aestivum L.) cropping system practised in >3 million ha of irrigated Aridisols in Pakistan is pivotal to its national economy and food security. Thus, the prevalent stagnation in its productivity is a matter of serious concern. Widespread deficiency of zinc (Zn) in these low organic matter alluvial calcareous soils is amongst the suspected constraints. Therefore, studying the impact of improved nutrient management strategies and crop residue recycling on crop productivity and soil Zn balances was thought imperative. Methods: A 5-year permanent layout field experiment was conducted on two predominant soil series of the cotton-wheat belt [i. e., Awagat (coarse loamy mixed, hyperthermic Fluventic Camborthid) and Shahpur (fine silty mixed, hyperthermic Fluventic Camborthid)] to compare the impact of (1) Farmers' fertilizer use (FFU); (2) Recommended fertilizer use (RFU); and (3) Integrated nutrient management (INM) on crop productivity and apparent soil Zn balances. The nutrient management strategies were compared with and without cotton-wheat residue recycling, in flat-bed sown and raised-bed sown cotton systems. Results: Under the FFU treatment, Zn deficiency occurred both in wheat and cotton. Overall lowest mean yields (Mg ha-1), obtained with FFU, were: seed cotton-Awagat, 2. 19; Shahpur, 2. 45; wheat grain-Awagat, 3. 03; Shahpur, 3. 94. Yield increases with RFU were: cotton, 24 % in Awagat and 18 % in Shahpur soil; wheat, 37 % in Awagat and 24 % in Shahpur soil (P ≤ 0. 05). With INM, crop yields were slightly higher than with RFU. Also, cotton yields were ~10 % greater on raised beds than on flat beds. Crop residue also increased yield of both crops, up to 10 %. Zinc uptake patterns of both crops were closely related to their yields. Fertilizer Zn use efficiency by the cotton-wheat system, in both soils, was quite low, i. e., 1. 78-2. 36 % of the annually applied 5 kg Zn ha-1. Thus, ~98 % of the applied Zn was retained (fixed) in the soils. Though Zn input from organic sources (i. e., crop residue and farm yard manure) was inadequate to meet crop requirements, Zn use efficiency from organic sources was much greater, i. e., 13-24 %. As Zn uptakes by the cropping system were quite low (i. e., 62-123 g Zn ha-1 by cotton; 74-170 g Zn ha-1 by wheat) compared with Zn inputs (i. e., 1. 12-1. 79 kg Zn ha-1 year-1), all nutrient management treatments, including FFU, resulted in positive apparent Zn balances in both soils. Conclusions: Thus, unlike nutrient balances for macronutrients, apparent Zn balances have little significance in predicting fertilizer Zn need of the cropping system. Despite positive soil Zn balances, even without using fertilizer Zn, prevalence of Zn deficiency in cotton and wheat crops may be attributed to high Zn fixation in calcareous soils rather than low total Zn content in the soils. In this scenario, soil testing and plant analysis remain the reliable approaches for diagnosing Zn deficiency problem. © 2012 Springer Science+Business Media B.V.

Shinwari Z.K.,Quaid-i-Azam University | Khalil A.T.,Quaid-i-Azam University | Nasim A.,Pakistan Academy of science
Archivum Immunologiae et Therapiae Experimentalis | Year: 2014

Over the last few decades biosecurity and biosafety have emerged as a prominent public health concern due to some high-profile accidents. Effective strategies to deal with the outbreak, whether deliberate or non-deliberate requires a multidisciplinary approach and coordinated decision-making by various state departments such as health, forensics, agriculture, environment, intelligence, law and enforcement, etc. In a dynamic global environment and the overwhelming asymmetric threats from the non-state actors, it is of utmost importance to understand the biosecurity issues and initiate a coordinated global effort to cope with biosecurity and biosafety breaches and develop an as effective response mechanism. An attractive choice for the terrorists, state enemies and non-state actors is the use of biological weapons. An unwanted incident may not only bring chaos to the people, but also can inflict severe economic damage industrially and locally as was in the notorious foot-and-mouth disease outbreak. Because of special geopolitical compulsion, Pakistan is one of the hot spots where special action needs to be taken. The current review focuses on the various approaches, technologies that can be used to alleviate the chances of biosafety and biosecurity incident and emphasizes the role of modern technology that can be used in this regard. © 2014 L. Hirszfeld Institute of Immunology and Experimental Therapy.

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