Search or add a thesis

Advanced Search (Beta)
Home > Morphological and Biochemical Adaptations of Local Cultivars of Barley Hordeum Vulgare L. under Drought

Morphological and Biochemical Adaptations of Local Cultivars of Barley Hordeum Vulgare L. under Drought

Thesis Info

Access Option

External Link

Author

Kausar, Rehana

Program

PhD

Institute

Pir Mehr Ali Shah Arid Agriculture University

City

Rawalpindi

Province

Punjab

Country

Pakistan

Thesis Completing Year

2015

Thesis Completion Status

Completed

Subject

Botany

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/7653/1/Rehana%20Kausar%2006-arid-764%20Ph.D%20Thesis%20full%20pdf.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676726725125

Similar


Barley (Hordeum vulgare L.) ranks fifth among important crops worldwide having the annual production of 136 million metric tonnes. In comparison with other cereal crops, it is more tolerant to water shortage, cold environments and salinity and hence is a crop of marginal lands. Drought is an important factor limiting barley yield because about two third of the area of barley production in Pakistan is rainfed. The present study was focused to unravel the morphological and biochemical dynamics and processes underlying adaptation to drought in local genotypes of barley. After initial screening in hydroponics at early growth stage, the barley genotypes were grouped into drought sensitive and tolerant categories using Ward’s hierarchical clustering procedure. The drought sensitive group comprised of nine genotypes (004186, Jau-83, Sanober-96, 004222, Haider-93, 004325, 005130, Soorab-96 and Jau-87) while the tolerant group consisted of six genotypes (004223, 004360, Frontier -87, 004201, 017655 and 005137). Drought linked simple sequence repeat (SSR) primers also separated sensitive and tolerant genotypes into different groups in UPGMA clustering. Among the drought sensitive group, 004186 was found to be the most sensitive genotype and 004223 as the most tolerant one in the tolerant group. Dehydrins are the proteins who play an important role in plant adaptation to drought. Immunoblots were used to characterize dehydrins in local barley genotypes. The maximum dehydrin expression was found in the most drought tolerant genotype 004223 while the most sensitive genotype 004186 lack this expression. Further characterizations of barley genotypes were done in a pot experiment at tillering, booting and milking stages of development. The data recorded was analysed using CRD. The milking stage came out 18 to be the most responsive towards drought. Genetic diversity analysis was done using Inter simple sequence repeat (ISSR) primers. The resultant dendrogram clustered barley cultivars and landraces into two separate groups. Global changes in protein profiles of the most sensitive (004186) and the most tolerant genotype (004223) were further investigated using proteomics technique. After the extraction of proteins from shoots, their separation was carried out by 2D-PAGE and staining was done with coomassie brilliant blue. Among the commom proteins between sensitive and tolerant genotypes in response to drought, the expression of Vacuolar Proton ATPase subunit E was increased while Photosystem I reaction centre II was decreased. Many of the proteins involved in photosynthesis and metabolism were decreased in the sensitive genotype under drought, however, they were increased in the tolerant genotype. Similarly, proteins related to energy, defense and transportation were also increased in the tolerant genotype only. To further investigate the response of three most drought tolerant genotypes (004223, 004360 and Frontier-87), a confirmatory experiment was conducted using proteomics approach. Among these genotypes, the twofold increase in the expression of Alpha SNAP and Methionine synthase alongwith Glycine decarboxylase indicated their crucial role in water stress tolerance. In conclusion, these target proteins involved in maintaining ion balance, chromatin protection and suppression of ROS came out to be the candidates for drought stress acclimation in barley genotypes.
Loading...
Loading...

Similar Books

Loading...

Similar Chapters

Loading...

Similar News

Loading...

Similar Articles

Loading...

Similar Article Headings

Loading...

الباب الثالث: الشاعرة المعروفة بروين شاکر

الباب الثالث: الشاعرة المعروفة بروين شاکر

بروین شاکر شاعرۃ أردیۃ معروفۃ، ولدت، وتعلمت في کراتشي، وھي أکبر شاعرات الباکستان، ولکن أصل أجدادھا من الھند، وسنتحدث في ھذا الباب عن ھذہِ الشاعرۃ المعروفۃ من حیث ولادتھا، نشأتھا، تعلیمھا، زواجھا، دواوینھا، عملھا الأدبي، أولادھا، أعمالھا غیر الأدبیۃ ثقافتھا، ثم وفاتھا، وأھم مؤلفاتھا الشعریۃ، وأهمية قصائدھا بین الشاعرات الأخریات باعتبارها من أعظم شاعرات الغزل الأردو الحر والحزین ومکانتھا بین الشعراء والشاعرات وفکرتھا عن العشق وأسلوبھا في الشعر۔

اسلامی فوجداریت کا ضابطۂ قرائن

Qara’in - usually translated as circumstantial evidence - is a derived form of Arabic word " " قر ن which literally means a fact associated or accompanied with an event or circumstances. But when an event or circumstances discloses such associated or accompanied fact then such a fact becomes circumstantial evidence. Both proto-juristic and modern legal terms held circumstantial evidence for an evidence which is offered to prove certain attendant circumstances from which the existence of the fact at issue may be inferred. In Islamic Law, majority of jurists do not endorse Qara’in as an authoritative evidence, particularly, in offences leading to corporal punishments. On the other side, Ibn Farhun from Malikites and Ibn Qayyem from Hanbalites terms it equal to the direct evidence of Iqrar and Shahadah. It is not very strange that Dr. Anwarullah, a prominent Muslim scholar and Prof. Robert Preach are of the opinion that circumstantial evidence is, after all, more authentic even than the aforesaid two evidences. Herbert Broom- a western legal expert- also says that certain hidden facts can be deducted from the mode of a relevant act or to some extent it is modus operandi which gives birth to a circumstantial evidence. In this shortened article the juristic opinion of some early and contemporary legal experts has been discussed as to judge the legal mode and authenticity of circumstantial evidence.

Search of Cotton Leaf Curl Vurl Tolerant Gene S by Differential Display

Cotton Leaf Curl Virus (CLCuV) is mainly one of the ruthless cause of cotton damage in Pakistan for which, until now, no passable therapy is available. In my present work, the local tolerant cultivar of Gossypium hirsutum (CIM-482) was initially tested via cotton leaf curl virus disease (CLCuD) epidemiological studies using reported disease rating scale and molecular diagnostic PCR technique. A susceptible cotton cultivar (S-12) was also used as inoculum source during disease optimization and as positive control for CLCuV infection in molecular detection of CLCuV from experimental plants. Disease epidemiological studies and molecular diagnostics confirmed CIM-482 as highly tolerant and S-12 as highly susceptible cotton variety. For the identification of CLCuV inducible genes, comparison of gene expression between control and tolerant plants was carried out using Differential Display Reverse Transcriptase PCR (DDRT) approach. Screening through 99 primer-pair combinations of 15 arbitrary and 12 anchored primers resulted in up-regulation of 42 cDNA transcripts from the tolerant samples which consistently displayed high differential intensity in comparison to control under disease stress. Only 18 differentially expressed transcripts (DETs) ranging in size from 103-1145bp were screened out as induced gene fragments; the other 24 were abandoned since false positives through reamplification, cloning & sequencing. The identified transcripts are reported first time against CLCuV infectivity and submitted as novel ESTs to GenBank database with accession numbers JZ495600- JZ495613. Homology search revealed that out of 18 transcripts, 14 showed very significant homologies with reported gene/ protein sequences while the rest of 4 transcripts remained uncharacterized due to non-significant homology with any of the known genes/proteins. The mRNA expression profiling via real time PCR of DETs also revealed that most of the transcripts showed up-regulated expression in tolerant samples as compared to controls except that of DET3 (P2T6a) and DET10 (P5T4b) which showed non-significant expression in disease tolerance. On the basis of highly up-regulated expression profile of DET17, transposon filtration and significant homology of transcript DET17 (P9T6a) with Gossypium arboreum protein, supposedly involved against CLCuV disease, it was selected and full length gene, G. hirsutum DNA-binding disease resistance RPS2-like gene (GhRPS2), with accession number KR809372, amplification was carried out through RACE (Rapid Amplification of cDNA Ends). A nucleotide sequence of 2677bp generated of 767 amino acids long open reading frame, which has 87.19kDa protein. It also has an upstream 5‟-UTR of 204bp and a downstream 3‟-UTR sequence of 169bp. The gene expression level was also confirmed and evaluated by real-time PCR which revealed high expression as compared to CLCuV diseased leaves. The genomic DNA PCR of full-length gene revealed that no introns were detected in the protein encoding sequence of GhRPS2 gene. Gene homology studies using bioinformatics tools depicted that GhRPS2 protein possessed high percentage similarity within the same taxon ranging from 98% to 92% with predicted disease resistance proteins of Gossypium spp. (G. hirsutum, G. arboreum and G. raimondii). It also exhibited 85% similarity with predicted bHLH transcription factors of above mentioned Gossypium spp. These percentage similarities are elevated enough for consideration of GhRPS2 protein to be DNA-binding protein family member, conferring disease resistance. The consensus sequences of two functional protein domains were found in the GhRPS2 protein .i.e., Leucine rich-repeat (LRR) domain and basic-helix loop helix (bHLH) DNA-binding protein domain. InterProScan results revealed the predicted GhRPS2 protein to be a member of transcription factor-related protein family. The diverse online sub cellular localization servers depicted that GhRPS2 protein might be localized in nucleus and cell membrane. The functional annotation of GhRPS2 sequence via Blast2Go analysis revealed its significant homology with disease resistance RPS-2 like protein of Gossypium arboreum (KHG12782). G. arboreum was also found to be the top hit species with highest similarity index. Functional annotation of full-length gene (GhRPS2) at molecular level depicted that it is involved mainly in binding activity with protein and nucleic acids, having dimerization capability for proteins and transcriptional regulation while binding with DNA. The signaling pathway map of GhRPS2 gene, identified using KEGG pathway database clearly indicated a signaling map related to plant-pathogen interactions. The likely function of GhRPS2 gene from this pathway map was revealed to be in the effector-triggered immunity. RPS2 gene (KEGG id: K13459) in combination with other defense related genes ultimately led to hypersensitive response (HR) which itself is a defense mechanism against pathogenic infections in plants. The tissue-specific expression profiling of GhRPS2 gene via real-time PCR from leaf, root & stem tissues which clearly displayed high expression of GhRPS2 in leaf tissue in comparison to stem and roots.