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Islolation and Characterization of Plant Based Pesticides

Thesis Info

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Author

Khan, Saira

Program

PhD

Institute

COMSATS University Islamabad

City

Islamabad

Province

Islamabad.

Country

Pakistan

Thesis Completing Year

2018

Thesis Completion Status

Completed

Subject

Biotechnology

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/12660/1/Saira%20Khan_Comsats.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676726527235

Similar


Isolation and Characterization of Plant Based Pesticides With the pace of constant population growth, the demand for sufficient and safer food is continuously increasing around the globe. On the other hand, global loss to crops due to pests, diseases and weeds is significantly high, warranting excessive use of pesticides, threatning environmnet and food safety. The most frequently used pesticides are synthetic posing several associated pre and post application problems such as residual toxicity that results in compromising the safety of food and causing insect resistance. An alternative approach may be to utilize plant’s secondary metabolites that plants actually synthesize in their defense against pests and pathogens. The major aim of current research study was, therefore, to identify, isolate, and characterize at biochemical and molecular level the potent insecticidal compounds from plant sources. To achieve this aim, seven plants namely Cinnamomum camphora, Eucalyptus sideroxylon, Isodon rugosus, Boenninghausenia albiflora, Calotropis procera, Daphne mucronata, and Tagetes minuta were selected. The crude and purified extracts of each of these plants were used to screen for their toxic effects against six economically important agricultural pests, each representing a separate insect order; Acyrthosiphon pisum (Hemiptera), Drosophila melanogaster (Diptera), Tribolium castaneum (Coleoptera), Spodoptera exigua (Lepidoptera), Schizaphis graminum (Hemiptera) and Bactrocera zonata (Diptera). Aphids were the most susceptible insects with 100% mortality observed after 24 h for all the plant extracts tested. Further bioassays with lower concentrations of the plant extracts against aphids revealed that the extracts from Isodon rugosus (Lamiaceae) (LC50 36.2 ppm and LC90 102.1 ppm) and Daphne mucronata (Thymelaeaceae) (LC50 126.2 ppm and LC90 197.5 ppm) found out to be the most toxic to aphids, A. pisum. These most toxic and active plant extracts were further fractionated in different solvent fractions on polarity basis and their insecticidal activity was further evaluated. While all fractions showed considerable mortality in aphids, the most active was the butanol fraction from Isodon rugosus with an LC50 of 18 ppm and LC90 of 48.2 ppm. Further bioactivity guided fractionation of the butanol fraction results in isolation of bioactive principle compound that was identified through various spectroscopic techniques as rosmarinic acid with LC50 0.2 ppm and LC90 5.4 ppm. There was no significant difference between LCs of purified rosmarinic acid and of commercial rosmarinic acid. Further, two key genes, hydroxyphenylpyruvate reductase and rosmarinic acid synthase, known to involve in biosynthesis of rosmarinic acid were targeted to clone from Isodon rugosus. Only one of these genes, hydroxyphenylpyruvate reductase was successfully cloned in Isodon rugosus which consequently will open the way to explore all other genes responsible for biosynthesis of rosmarinic acid. The molecular knowledge regarding biosynthetic pathway will help in biotechnological production of rosmarinic acid and to produce aphid resistant plants through genetic engineering approaches. Considering the high mortality rate in aphids to a significantly low concentration of the rosmarinic acid from Isodon rugosus, could be exploited and further developed as a potential eco-friendly plant-based insecticide against sucking insect pests.
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ملازمت

اعلیٰ تعلیم حاصل کرنے کے بعد فکر معاش اور غم روزگار فطری بات ہے۔ لیکن پروفیسر عبدالحق نے جس طرح تن دہی اور جس مساعدت کے ساتھ اپنا علمی سفر طے کیا اس طرح سےا نہیں ملازمت میں بھی ہولیات فراہم ہوگئیں۔ ایک توان کی علمی لیاقت اور ادبی صلاحیتیں دوسری شریف اساتذہ کی سر پرستی اور پھر پروفیسر خواجہ احمد فاروتی جیسے جو ہر شناس کی تیز نگاہ جو ہر قابل کو پہچان گئی۔ ابھی پروفیسر عبد الحق پی۔ ایچ۔ ڈی کے وایوا سے فارغ ہی ہوئے تھے کہ پروفیسر محمد حسن نے پروفیسر خواجہ احمد فاروقی کے ایما پر پروفیسر محمود الہی صدر شعبہ اردو گورکھپور یو نیورسٹی کو خط لکھا جس میں پروفیسر عبدالحق کو دہلی طلب کرنے کے لیے لکھا تھا۔ یہاں شعبہ اردو دہلی یونیورسٹی دہلی میں تین مہینے کے لیے ایک عارضی جگہ خالی تھی۔ ڈاکٹر شرافت حسین مرزا جو ریسرچ اسٹنٹ کے طور پر کام کر رہے تھے وہ تین ماہ کی رخصت پر اپنے وطن جانے والے تھے۔ خواجہ احمد فاروقی کی یہ خوبی تھی کہ وہ کسی اسامی کو خالی رہتا نہیں دیکھ سکتے تھے۔ اس سال 1965 ء میں صدیق الرحمان قدوائی لیکچرار شعبہ اردو اپنے ریسرچ کے کام سے تین ماہ کی رخصت پر چلے گئے ۔ ان کی جگہ گورکھپور سے ڈاکٹر فضل الحق کو لیکچرر مقرر کر دیا گیا۔ پروفیسر عبدالحق کو بھی تین ماہ کے لیے دہلی طلب کیا گیا تھا لیکن جب وہ 17 دسمبر 1965ء کو دہلی تشریف لائے تو معلوم ہوا کہ ڈاکٹر شرافت حسین مرزا نے چھٹی کی درخواست واپس لے لی ہے تو پروفیسر عبد الحق واپس جون پور جانے کے لیے تیار ہو گئے لیکن خواجہ احمد فاروقی نے از راہ شفقت انہیں روک لیا اور تقریبا ًچھ ماہ کے بعد فاروقی صاحب(Post-Doctoral Fellowship) کی کوششوں سے...

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Mian Muhammadi (son of Hazrat Mian Umer) was a great sufi saint and Islamic scholar of Khyber Pakhtunkhwa Pakistan in 19th century and born in a well known village “Chamkani” of district Peshawar.  He was a multi dimensional personality of his time being a saint respectful to the all sects of Muslims, as a poet of Arabic and Pashto, and a scholar having a systematic program for publication of the books. He has authored a number of books in various fields of Islamic Studies and Shariah adopting a unique methodology in writing. He, the Mian Muhammadi, has spent his whole life in quenching the spiritual thirst of the local Muslim of that era on one hand, and spreading the knowledge on other hand. In the present paper, personal life, services as well as academic effects of this great saint have been discussed scholarly in order to bring forth his life sketch and contributions before the scholars.

Existence and Uniqueness of Solutions for Nonlinear Functional Equations

In 1922, the Polish mathematician Stefan Banach established a signicant xed point theorem known as the Banach Contraction Principle, BCP which is one of the most prominent results of analysis and considered to be the main source of metric xed point theory. It is the most widely applied xed point result in many branches of mathematics because it requires the structure of complete metric space with a contractive condition on the map which is easy to test in this setting. The BCP has been expanded in many di⁄erent directions. In fact, there is a huge amount of literature dealing with extensions/generalizations of this important theorem. A multivalued function is the one which takes values as a set. In the last forty years, the theory of multivalued functions has progressed in a number of ways. 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