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Home > The Response of Maize Zea Mays. L, to Exogenously Applied Sulfur under Saline Conditions

The Response of Maize Zea Mays. L, to Exogenously Applied Sulfur under Saline Conditions

Thesis Info

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Author

Riffat, Alia

Program

PhD

Institute

University of Agriculture

City

Faisalabad

Province

Punjab

Country

Pakistan

Thesis Completing Year

2016

Thesis Completion Status

Completed

Subject

Botany

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/9613/1/Alia_Riffat_Botany_UAF_2016.docx

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727593557

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Salt tolerant and salt sensitive cultivars of maize were screened for improvement in salinity tolerance by exogenously applied sulfur as K2SO4. Seeds of eight cultivars of maize were subjected to 0, 25, 50 and 75 mM NaCl. Six levels (0, 20, 40, 60, 80, 100 mM) of sulfur were prepared in Hoglands nutrient solution by using potassium sulphate and applied in sand culture at sowing time. Results showed that salt stress reduced all germination attributed such as; germination percentage, emergence index, mean emergence time, coefficient of uniformity of emergence, vigour index, coefficient of velocity of germination, germination energy, germination speed, mean daily germination, germination value and length, fresh, dry weights of plumule and radicle and ionic accumulation. Salt stress also caused a delay to achieve 50% germination in all selected maize cultivars. The lower levels of sulfur (20, 40, 60 and 80 mM) enhanced salinity tolerance of all studied maize cultivars. Though the highest level of sulfur (100 mM) also improved salinity tolerance to some extent, it was comparatively less effective as compared to lower levels. All germination and early growth data was fed to NTSyS PC software. The tree was generated based on distance matrixes of all attributes with a higher distance reflecting higher similarity between groups. All genotypes were clustered a tolerant group (Agatti 2003, MMRI, Pearl basic, Sadaf) and a sensitive group (Sahiwal 2003, Hybrid 1898, Pak Afgoi 2003, Yousaf wala hybrid). Among the tolerant group, the highest distance was calculated for Agatti 2003 while among salt sensitive group, the least distance was observed for Pak Afgoi 2003 and Hybrid 1898. All other genotypes had intermediate tolerance levels. Among the salt tolerant group, Agatti 2003 had more germination, growth and ionic accumulation at all levels of salinity as compared to other maize cultivars therefore selected as a tolerant variety for further studies. Among the sensitive group, PakAfgoi 2003 was selected as salt sensitive one because of lowest seed germination, growth and ionic accumulation attributes under salinity. From the findings of screening experiment, 25mM and 75mM concentration of NaCl and 40mM and 80mM of sulfur was selected for further study. In the second part, seeds of selected maize hybrids (Agatti 2003 and Pak Afgoi 2003) were subjected to salinity (25, 75 mM) and sulfur (40, 80 mM) as soil amendment. Sulfur (40, 80 mM) was also applied as foliar spray. The plants were harvested after 45 days of seed germination. Various growth, physiological and biochemical parameters were studied. The results of the second experiment revealed that sulfur application improved all growth and biochemical parameters studied. The concentration of different ions (K+, Ca2+, NO3-, PO42-, SO42-) were reduced by salt treatment in leaf, shoot and root of both varieties of maize. The concentration of phenolics, lycopene and carotenoids were increased by increasing sulfur that effectively scavenged MDA and H2O2 contents in Agatti 2003 and helped plants to tolerate adverse effects of salt stress. Excessive production of secondary metabolites, such as, alkaloids and flavonoids also contributed in enhancing salt tolerance in Agatti 2003. The total soluble sugars, total free amino acids and total soluble proteins increased to a greater extent in Agatti 2003 than Pak Afgoi 2003. In comparison sensitive cultivar Pak Afgoi 2003 had high Na+ ions, H2O2 and MDA concentration. It also exhibited lower concentration of osmoprotectants, vitamins, antioxidants, biomolecules that lowered its capability to tolerate salinity. Sulfur at 40 mM level proved to be very effective for improving all growth and biochemical parameters. While higher levels (80 mM) of sulfur were not proved much effective for growth enhancement of maize cultivars both in salinized and non-salinized conditions. The tagged plants from second experiment were harvested at full mature stage. The data was recorded for yield and yield components and forage value of maize shoot. Results showed that salt stress reduced all studied yield parameters including cob length, cob per plant, total number of cobs, total number of grains, weight of 50 grain, harvest index, yield per plant, ionic contents, protein, carbohydrate, starch, vitamin, ash, fiber and ionic contents (Na+, K+, Ca2+, NO3-, PO42-, SO42-) in leaves and grains. This decrease was accompanied with an increase in sodium contents in both maize varieties. Sulfur at 40 mM level effectively increased all studied yield and biochemical parameters. In conclusion, although both varieties responded differentially to the sulfur application, Agatti 2003 showed more tolerance to salt stress by application of sulfur as compared to Pak Afgoi 2003. Additionally, the lower level of sulfur (40 mM) was much more effective in enhancing salt tolerance potential of tested genotypes as compared to its higher level i.e. 80 mM S applied as K2SO4.
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ہم کہ زندانی ہیں جس کے پیار کے

ہم کہ زندانی ہیں جس کے پیار کے
چھیڑیے قصے نگاہِ یار کے

موت کی وادی ہے جلوہ حسن کا
عشق کے سب دائرے ہیں دار کے

آنکھ کے تیور، مَیں اُن کے کیا کہوں
دل جگر چھلنی ہیں اس تلوار کے

اُن سے دوری جان لیوا ہو گئی
قرب کے وعدے تھے مجھ سے یار کے

تم فضاؔ مجھ زیست کا سامان ہو
اولیں ہو آخریں بھی پیار کے

بلاغة القرآن الكريم وتحدت ترجمة المعاني القرآنية الثانية إلى اللغة الأردية

His research paper is meant to explain the difficulties of translation of rhetorical and implicit meanings of Qur᾽ān into Urdu language as the translation of such meanings of Qur᾽ān is seriously a difficult job for reasons including the tacit relationship of meanings with the words’ structure and because these meanings take effect of social and mental characteristics of a particular group of people speaking a common language and also for the reason that the meanings change their position with the incessantly changing condition of mind and culture. Given the above facts the writer put forth analysis of four Urdu translations of Sūrah Al-Ḍuḥā after having studied their rhetorical aspects and implicit meanings in interpretations of different interpreters. The translations are as under. 1. Translation of Shaykh Abdul Qādir (d. 1233 A. H) named as “Maudihul Qur᾽ān”. 2. Translation of Aḥmad Raḍa Khan Braylvi (d. 1340 A. H) named as “Kanz ul ᾽Īmān fi Tarjama Al-Qur᾽ān” 3. Translation of Ashraf ‘Alī Thānvi (d. 1362 AH) with the name “Bayān Al-Qur᾽ān”. 4. Translation of Abdul Mājid Daryā Abādī (d. 1977 A. D) which is in literary style with attractive language. The writer has highlighted the lapses and shortcomings of these translations in rhetorical perspectives of Qur᾽ān and its implicit meanings and has also underlined the difficulties faced by these translators in a descriptive table. Findings and suggestions are given at the end.

Experimental Investigations of Iron Oxide Based Nanostructures and Their Correlation With Theory

The present study deals with synthesis of different iron oxide (magnetite, maghemite and hematite) based nanostructures using sol-gel method. The main emphasis is to experimentally synthesize iron oxide based nanostructures and to correlate these results with theory. Molarity, pH, temperature and surfactant of the sol are important parameters to control morphology. Hence, in this research work all of the 4 parameters were optimized to study their effect on structural, morphological, optical and magnetic properties. In the first step seven different sols with varying concentrations from 1.8 to 0.6 mM are synthesized. The concentration of 1.4 mM results in a pure magnetite phase whereas others show mixed magnetite and maghemite phases. Free growth of iron oxide nanostructures, including nanoneedles, nanorods, nanospheres and nanobrushes, are observed in scanning electron microscope images. In the second step 1.4mM sol concentration is used and nine sols are synthesized with pH 1 to 9. Samples exhibit magnetite phase with superparamagnetic nature at low pH (1, 2 & 6) with 50nm diameter nanoparticles. For pH 3-5 hematite phase is observed while with further increase in pH (7&8) maghemite phase is achieved. Annealing for pH 1-8 only strengthened the existing phases rather than transformation. Maghemite and hametite phases are observed at pH 9 with annealing at 200 oC and 300 oC respectively. In the third step effect of surfactants was studied in detail. PVA, triton X-100 and oleic acid are used as surfactants. Sols thus prepared are analyzed magnetically before and after room temperature aging. Superparamagnetic behaviour is observed for iron oxide sol synthesized using oleic acid as surfactant, and therefore was selected for further studies. The amount of oleic acid is varied as 5%, 10% and 15% by volume. Shape and morphology of iron oxide nanoparticles strongly depend on calcination temperature, which is varied from 300˚C to 900˚C. Iron oxide sol with 15% by volume show superparamagnetic behavior while sols prepared with 5% and 10% oleic acid show dia-ferromagnetic and para-ferromagnetic mixed behavior. Two types of NPs are observed in SEM images; one with shell and one without shell with 10% oleic acid. Cubic NPs with size less than 25nm and highest dielectric constant of ~107.5 (log f = 5.0) is observed with 15% oleic acid at 500˚C. ZnO is selected for iron oxide based nanostructures. Once again sol-gel method has been employed for synthesis of iron oxide added ZnO nanoparticles. The dopant concentration is varied as 1wt% to 5wt%. Ferromagnetic behavior of Fe added ZnO nanoparticles arise due to the presence of long range oscillating interactions among the free charge carriers. The band gap of these iron oxide based nanostructures is in the range of 3.05eV to 3.48eV. Mn/Fe co-doped ZnO structures are also prepared by simple sol-gel and spin coating method. Five different sols with the change in concentration (1-5wt%) of both Mn and Fe are synthesized. Molar ratio of Mn and Fe is kept constant, i.e., 1:1. Sols are spun onto glass and copper substrates by spin coating method followed by the post magnetic field annealing at 300 ˚C for 1 h. XRD results show incorporation of Mn and Fe in the host lattice up to a dopant concentration of 4wt%. Small crystallites of Mn and Fe2O3 are observed by increasing the dopant concentration to 5wt%. VSM results indicate room temperature ferromagnetism in all samples. Moreover, Mn/Fe co-doped thin films show magnetic hysteresis equivalent to that of multilayered structure, indicating that such complex structures can be replaced by a single ZnO layer with co-doping of Mn and Fe. Density functional theory is used for the theoretical investigation of iron oxide based nanostructures. Amsterdam Density Functional (ADF) software with BAND tool is used. Generalized Gradient Approximation (GGA) and Local Density Approximation (LDA) are used in order to correlate structural, optical and magnetic properties of iron oxide based nanostructures. With basis set of TZ2P geometry optimization is achieved. Underestimation of electronic properties of all phases is observed by GGA and LDA. While, improved value of band gap is obtained by GGA+U and LDA+U. Exchange correlational potential is also optimized in case of GGA+U calculations. Hubbard potential (U eV) is optimized and lowest value of U i.e. 0.6 eV is used for all calculations for wüstite, hematite, maghemite and magnetite. Total DOS and partial density of states for iron and oxygen are also studied for both approximations. Analysis of the density of states confirms the strong hybridization between Fe 3d and O 2p states in iron oxide. In all cases (magnetite, maghemite and hematite) density of states plots confirm that the main reason for the magnetic properties in iron oxide based nanostructures is the d orbital electrons. As a result, a good correlation of theory with experiment is being reported in this thesis.