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Home > Influence of Nickel Stress on Growth, Morpho- Physiological and Anatomical Attributes of Sunflower Helianthus Annuus L.

Influence of Nickel Stress on Growth, Morpho- Physiological and Anatomical Attributes of Sunflower Helianthus Annuus L.

Thesis Info

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External Link

Author

Muhammad Sajid Aqeel Ahmad

Program

PhD

Institute

University of Agriculture

City

Faisalabad

Province

Punjab

Country

Pakistan

Thesis Completing Year

2011

Thesis Completion Status

Completed

Subject

Natural Sciences

Language

English

Link

http://prr.hec.gov.pk/jspui/handle/123456789/1866

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676726459594

Similar


The phytotoxic effects of Ni-stress on seed germination, growth, physiological and anatomical attributes were appraised in this study. The available sunflower germplasm was exposed to varying levels of Ni (0, 10, 20, 30, 40, 50 and 60 mg L -1 ). The lowest level of nickel (10 mg L -1 ) showed some improvement in seed germination and reduced the time to achieve 50% germination; it was found to be associated with improvement in Mg contents, activity of hydrolytic enzymes and concentration of reducing and non- reducing sugars, and free amino acid over time. However, higher levels of nickel had a significant inhibitory effect on seed germination that was directly correlated with reduction in K and activity of hydrolytic enzymes leading to alterations in concentration of crucial bio-molecules involved in control of seed germination. Based on the data generated a Ni-tolerant (Hysun-33) and a -sensitive (SF-187) hybrids were selected for further studies. In vegetative stage experiments, seeds of two selected sunflower hybrids were exposed to different levels of Ni (0, 10, 20, 30 and 40 mg L -1 ). Although low levels of Ni had a non- significant effects, high Ni-levels significantly reduced vegetative growth and yield has result of reduction in photosynthetic rate (A), stomatal conductance (g s ), water use efficiency (WUE) and Ci/Ca ratio. However, transpiration rate (E) increased with increase in external nickel. Leaf water and turgor potentials, and relative water contents (RWC) decreased while leaf turgor potential and membrane permeability (electrolyte leakage) increased in both sunflower hybrids. The concentration of soluble proteins increased at lower level of Ni application (10 and 20 mg L -1 ) but decreased with further increase in concentration of external Ni in all harvest intervals. However, the reverse was true for the concentration of free amino acids and soluble sugars. Proline concentration increased consistently with increasing concentration of external Ni. The concentration of nutrients such as Ca, N, P, K, Cu, Zn, Mg, Mn and Fe generally decreased in root, stem, leaves as well as achenes except for achene P and Mg which were not much affected under Ni-stress. The changes in all growth, biochemical, and physiological parameters appeared to be highly correlated with build-up of high Ni levels in root, stem and leaves of both sunflower hybrids over time. The anatomical features of root, stem and leaves were also significantly altered under Ni stress. Root exodermal thickness increased at the lowest level of Ni application (10 mg L - 1 ) but decreased consistently with further increase in Ni concentration. In contrast, root exodermal cell area, increased consistently with increase in external Ni concentration. Shoot and leaf exodermal and second layer thickness and area also increased consistently with increase in external Ni levels. Although, root, stem and leaf cortical, vascular region, metaxylem and phloem thickness and area were not affected at the lowest level (10 mg L - 1 ) of Ni, it decreased consistently with increase in external Ni as well as plant maturity. The reverse was true for leaf adaxial and abaxial stomatal density. In comparison, their thickness decreased during early stages but increased with increasing plant maturity. Leaf abaxial epidermal thickness and area, and leaf lamina thickness increased but spongy mesophyll thickness and area decreased with increase in external Ni as well as time. On the basis of data presented in this study, Hysun-33 was found to be more tolerant as compared to that of SF-187.
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تعداد ازواج

تعدد ازواج
وَلَقَد اَرسَلناَ رَسُلاََ مِنّ قَبلِکَ وَ جَعَلناَ لَھُم اَزوَاجاََ وَّ ذُرِّ یَّۃََ ( رعد۔ع۶)
ََ ڈاکٹر محمد حمید اللہ ( پیغمبر اسلام ۲۲۸۔۲۲۷) لکھتے ہیں تاریخی طور پر کسی مذہب کے قوانین میں بیویوں کی تعداد پر کہیں پابندی نہیں لگائی گئی۔ بائبل میں مذکور تمام پیغمبروں کی ایک سے زیادہ بیویاں تھیں حتیٰ کہ عیسائیت میں بھی جو’’ ایک وقت میں ایک بیوی‘‘ کے قانون کی علامت بن گئی ہے‘ عیسیٰ ؑ نے خود بھی کبھی تعداد ازواج کے خلاف ایک لفظ نہیں کہا جب کہ مذہبی علوم کے ممتاز مسیحی ماہرین مثلاََ لوتھر میلنتھون اور بوسر وغیرہ نے تو میتھو کی انجیل (۲۵۔۱۔۱۲) میں دس کنواریوں کی تمثیل سے تعداد ازواج کا جو از حاصل کرنے میں کسی ہچکچاہٹ کا مظاہرہ نہیں کیا کہ عیسیٰ ؑ بیک وقت ایک مرد کی دس لڑکیوں سے شادی کے امکان کو پیشِ نظر رکھ رہے تھے۔اگر مسیحی اس اجازت سے فائدہ اٹھانا نہیں چاہتے( جو ان کے مذہب کے بانی نے دی) تو قانون بہ ہر حال تبدیل نہیں ہوا۔ (حاشیہ پر رقم طراز ہیں )یک زوجگی ( ایک وقت میں ایک بیوی) کا اس طرح تصور کہ دوسری شادی( بہ یک وقت دو بیویاں) کو سنگین جرم ، گناہ اور لعنت قرار دیا جائے بہت کم یاب ہے اور شادی کے ایسے منفرد ، مثالی اور کڑے پن پر مبنی نظریہ کی مثال آج کے جدید دور سے پہلے شاید ہی ملتی ہو اور یہ صورت حال بھی مغربی تہذیب کی دورِ حاضر کی جدیدیت کا ثمر ہے۔ یہ مسیحی دینی نظریہ سے اخذ کردہ قانون نہیں۔( انسائکلو پیڈیا۔ باب شادی)
یہ نہیں کہا جا سکتا کہ یک زوجگی ، مسیحیت نے مغربی دنیا میں متعارف کروائی۔ مسیحیت بشپ اور پادری کے سوا باقی لوگوں کے لیے تعداد ازواج یعنی ایک سے زیادہ شادی...

The Health and Sanitary Status of Mamanwa Indigenous People in Selected Areas in Caraga Region

This study aims to determine the health and sanitary status of the Mamanwa indigenous people in selected areas in CARAGA Region. The respondents were the Mamanwa people who are residents of Cantugas, Mainit, Surigao del Norte community, and Kitcharao, Agusan del Norte community. The study used descriptive research design utilizing questionnaire and personal interview in gathering the data. The total population of the respondents is 69 and respondents from both communities were selected based on simple random design.   The study used percentage and mode/majority criterion, weighted mean, and Kendal-tau correlation. The findings showed that in the extent of health and sanitation education which was divided into three factors: Factor 1 which is the regularity of adopting health and sanitation practices shows a mean rating described as always except for item 9. Factor 2 was about exposure to health and sanitation campaign and education show a mean rating of sometimes. Factor 3 is about awareness on health and sanitation show a mean rating of sometimes. On the economic status of Mamanwa people which was the (factor 1) economic status of Mamanwa parents, 75.4% of the Mamanwa parents send their children to school and 64.9% of Mamanwa parents’ allocated budget for clothing and other personal necessities. On social status of the location (factor 2), only 35.1% of the respondents said that they have proper waste disposal and segregation.  The results showed that Mamanwa children regardless of sex and age were undernourished and there is a significant relationship between the regularity of adopting health and sanitation practices with hygiene on health care where it had an R-value of 0.47 and 0.35 respectively. Lastly, only economic factor on the social status of the location had a significant relationship on the health status of Mamanwa children in terms of BMI which had an R-value -0.20 and p-value 0.049.

An Efficient Scheme for Lung Nodule Detection

Lung cancer has been one of the major threats to human life for decades in both developed and under developed countries with the smallest rate of survival after diagnosis. The survival rate can be increased by early nodule detection. Computer Aided Detection (CAD) can be an important tool for early lung nodule detection and preventing the deaths caused by the lung cancer. In this dissertation, we have proposed a novel technique for lung nodule detection using a hybrid feature set. The proposed method starts with pre-processing, removing any present noise from input images, followed by lung segmentation using optimal thresholding. Then the image is enhanced using multi scale dot enhancement filtering prior to nodule detection and feature extraction. Finally, classification of lung nodules is achieved using Support Vector Machine (SVM) classifier. The feature set consists of intensity, shape (2D and 3D) and texture features, which have been selected to optimize the sensitivity and reduce false positives. In addition to SVM, some other supervised classifiers like K-Nearest-Neighbour (KNN), Decision Tree and Linear Discriminant Analysis (LDA) have also been used for performance comparison. The extracted features have also been compared class-vise to determine the most relevant features for lung nodule detection. The proposed system has been evaluated using 850 scans from Lung Image Database Consortium (LIDC) dataset and k-fold cross validation scheme. The main research work done in this dissertation is summarized in the following section. 1. The proposed method starts with the segmentation of lung volume from pre-processed input CT images. Lung segmentation has a critical importance as it is pre-requisite to the nodule detection. Any in-accurate lung volume segmentation can lead to the low accuracy of whole system. In this dissertation, we propose a fully automated segmentation method for lung volume from CT scan images which consists of series of steps. Initially, the CT image is segmented by using optimal thresholding and the lung volume is obtained using connected component labeling method and other irrelevant information is removed at this stage. The resultant image at this stage contains holes which is filled with the hole filling algorithm e.g. morphological operations. Finally, the lung contour is smoothed by rolling ball algorithm to include any juxta pleural nodules. 2. After lung segmentation, image enhancement is done to detect the low-density nodules. Image enhancement plays an important role in detection of these nodules by enhancing them and reducing false positives by weakening the other structures in lung region. In this thesis, a multi scale dot enhancement filter is used to detect these low-density nodules which may remain undetected in the absence of any enhancement algorithm and can affect the accuracy of the system. In the first step, a Gaussian smoothing on all the corresponding 2D slices is performed to reduce the noise and sensitivity effect. After Gaussian smoothing, Hessian matrix and its eigen values |?2|<|?1| are calculated for every pixel to determine the local shape of the structure. The suspected pulmonary nodule region exhibits the form of a circular or oval object whereas vascular tissue structures presents a line-like elongated structure. Therefore, this property can be used to distinguish different shape structures present in lung region. This process is repeated for different scales and finally we integrate the filter’s output values to obtain the maximum value for the best enhanced effect and generate the resultant image. After image enhancement, lung nodule candidates are detected using optimal thresholding. Then a rule-based analysis has been made based on some initial measurements like area, diameter and volume whether to keep or discard the detected nodule candidate. The advantage of rule-based analysis is that it eliminates the objects which are too small or too big to be considered as a nodule candidate and thus reduces the workload for the next stage. 3. A hybrid feature set is obtained after rigorous experimentation which increases the classification accuracy and reduces the false positive per scan considerably. The proposed feature set plays a crucial role in the overall performance of the CAD system. We selected a large pool of features initially and then trimmed down the set on the basis of accuracy and false positive per scan and ultimately obtained the proposed hybrid feature set. 4. The classification of pulmonary nodules is done using SVM algorithm. In the classification phase, the suspected pulmonary nodules are divided into true pulmonary nodules and false pulmonary nodules. SVM as a high-dimensional multi-feature hyperplane differentiation algorithm performs considerably well in a situation where it must decide only between the two classes i.e., nodule or non-nodule and the features of the suspected pulmonary nodules refer mainly to the two classes and the Gaussian Radial Basis Function (RBF) kernel function can increase its linear separability which makes the detection and classification of pulmonary nodules more accurate. 5. We have done an extensive evaluation of our proposed system on Lung Image Database Consortium (LIDC). LIDC is a publicly available database accessible from The Cancer Imaging Archive (TCIA). We have considered the 850 scans (LIDC-IDRI-0001 to LIDC-IDRI 0844) of this dataset, which contains nodules of size 3-30 mm fully annotated by four expert radiologists in two consecutive sessions. K-fold cross-validation scheme is used for model selection and validation whereas the k value varies for 5, 7 and 10. An exhaustive grid search has been used to tune the hyperparameters of SVM classifier. Some other classifiers have also been used for classification of lung nodule candidates. An attempt has also been made to determine the most relevant feature class for lung nodule detection system. The achieved sensitivities at detection and classification stages are 94.20% and 98.15%, respectively, with only 2.19 FP/scan. The results of our proposed method show the superiority of our scheme as compared to other systems with increased sensitivity and reduced FP/scan. The main contribution of this dissertation is the presentation of a relatively simple nodule detection scheme that has a very good performance in an extensive experimental analysis. In addition, the proposed feature set has helped in reducing the false positives significantly and has increased the sensitivity of the proposed system. Moreover, a comparison has been made to determine the most relevant feature class in extracted feature set. The overall sensitivity has been improved compared to the previous methods and FP/scan have been reduced significantly.