Shahjahan Ahmed | Balochistan University of IT, Engineering and Management Sciences, Quetta. (original) (raw)

Papers by Shahjahan Ahmed

International Journal of Biology and Biotechnology, 2015

Rice is a staple food to almost one-third population of the world. The crop sustainability must t... more Rice is a staple food to almost one-third population of the world. The crop sustainability must therefore be considered to keep pace with the growing world population. Microorganims are one of the key factors affecting crop productivity and quality. Of particular interest is the plant rhiszosphere microbiome which has gained enormous attention in recent years due to their role both as pathogen and plant growth promoting agents. Accordingly, the present study is aimed at identification of bacteria isolated from soil samples collected from rice fields of district Jaffarabad, which belongs to the major rice growing area of Pakistan. Six strains B9, B15, B34, B40, B52 and B53 were identified as genus Bacillus whereas isolate B12 as genus Staphylococcus based on morphological and biochemical properties and 16S rRNA gene sequence analysis. Isolates B9, B40 and B53 showed 99% similarity to Bacillus thuringiensis, Bacillus anthracis and Bacillus endophyticus respectively. Conflicting result...

Journal of Applied and Emerging Sciences, 2016

An elevated content of arsenic (As) in ground water in large area of Pakistan is becoming a serio... more An elevated content of arsenic (As) in ground water in large area of Pakistan is becoming a serious threat to its inhabitants. Hi-tech technologies may not be feasible to remove As in rural and poverty hit areas of Pakistan because of being expensive and high operational costs. Some of the aboriginal technologies which involve Evaporation, co-precipitation and oxidation techniques are in use in rural areas of many regional countries like India, Bangladesh and Nepal quite successfully. These indigenous technologies have been proved to be good alternative to modern technologies. They are highly resilient and have great adaptability to our local conditions and can be used as good adaptable options in the scenario of climate change and increased water pollution. For operation of these technologies no electricity is needed and no pressure is required. No expensive chemicals, no mechanical complexity and no expensive membranes are involved in fabrication of these equipments. Yet highly pr...

Bu calisma marul (Lactuca sativa L.)'da buyume ve tohum veriminde farkli fosfor duzeylerinin ... more Bu calisma marul (Lactuca sativa L.)'da buyume ve tohum veriminde farkli fosfor duzeylerinin etkisini arastirmak amaciyla yapilmistir. Iki farkli marul cesidi, Grand Rapids ve Romaine sirasiyla 60 kg/ha ve 80 kg/ha olmak uzere iki farkli fosforlu gubre duzeyinde tesaduf bloklari (RCBD) deneme deseni kullanarak test edilmistir. Denemelerin fosfor olmaksizin tohum parametreleri ile duyusal olarak degerlendirmesinin yani sira, tohumun gevrekligi ve rengi her 10 gunde bir incelenmistir. Fosforlu gubrenin artisinin her iki marul cesidinin verimi, yer ortusu ve raf omru uzerinde olumlu bir etkiye sahip oldugu gorulmustur. Bununla birlikte, Romaine cesidine kiyasla Grand Rapids cesidinin tohum gelisiminde faz gecisi olmasi icin yeterli olcude soguga maruz kalmamasina ragmen, Grand Rapids’in verim bakimindan Romaine’den onemli olcude daha ustun bir performans gosterdigi bildirilmistir. Test edilen iki marul cesidinin daha iyi bir verim ve tohum gelisimi gostermelerini etkileyecek olan b...

Journal of Applied and Emerging Sciences, 2016

Tomato (Solanum lycopersicum L.) hybrid variety trials were conducted at “Directorate of vegetabl... more Tomato (Solanum lycopersicum L.) hybrid variety trials were conducted at “Directorate of vegetable seed production farm Quetta” where two varieties of tomato (Riogrande & Dolor) were evaluated on the basis of days to flowering, fruit setting, length and width of fruit, average fruit weight, plant height , yield, maturity period and producing new hybrid variety which is suitable for climate prevailing in Quetta. The development strategy was “Inter-varietal Hybridization” and hybrid progeny often have a higher yield, increased resistance to disease, and an enhanced performance in different environment compared with the parental lines. Cost effective mechanism to create commercial hybrid seed parental line is one of the vital components which ultimately examine the commercial viability of hybrid varieties. Emasculation was aimed at first generation (F1) hybrid seed utilization globally in term of salient cultivars and volume of utilized seed. (F1) hybrid seed can be characterized into ...

Genetics and Molecular Research, 2012

Cytoplasmic male sterile line RC 7 of Chinese cabbage produces mature anthers without pollen. To ... more Cytoplasmic male sterile line RC 7 of Chinese cabbage produces mature anthers without pollen. To understand the mechanisms involved, we examined the ultrastructural changes during development of the microspores. Development of microspores was not affected at the early tetrad stage. During the ring-vacuolated period, some large vacuoles appeared in the tapetum cells, making them larger, extending to the anther sac center during the monocyte period. At the same time, the tapetum degenerated as the microspores aborted, resulting in pollendeficient anthers. As a result, the locules collapsed and the anthers shriveled. The callose was degraded in the pollen walls; abnormal deposits of electrodense material gave rise to irregular spike-shaped structures, rather than the characteristic rod-like shape of the B7 bacula. The internal intine wall of RC 7 was thinner than that of the B7 type. At the mitosis I microspore stage, the tapetum cells contained multiple plastids, with numerous small spherical plastoglobuli, and lipid bodies. Based on these observations, we suggest that RC 7 abortion may be due ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 11 (4): 4145-4156 (2012) H.-F. Zhao et al. to mutated genes that normally regulate development of the pollen wall and cell walls in the RC 7 line.

American Journal of Botany, 1986

Immature cotyledons of open-pollinated fruits from three sour cherry cultivars (Prunus cerasus L.... more Immature cotyledons of open-pollinated fruits from three sour cherry cultivars (Prunus cerasus L.) were excised and cultured on Murashige and Skoog medium supplemented with various combinations of auxin and cytokinin to induce somatic embryogenesis. Somatic embryogenesis occurred principally when using the combinations of 2,4-dichlorophenoxyacetic acid plus kinetin. Using a-naphthaleneacetic acid or 6-benzylaminopurine reduced the incidence of somatic embryogenesis. Conversely, formation of cotyledon-like structures, leaves, shoots and roots was enhanced. The addition of 0.1 mg l À1 3-indolebutyric acid to the inductive medium was beneficial to the induction of somatic embryogenesis. In a few cases, secondary somatic embryos formed and well-developed somatic embryos germinated. Of the three cultivars tested,`Scharo È' was less responsive than`Gerema' and`Schattenmorelle' when cultured under equivalent conditions. After trisectioning the cotyledons of cultivar`Gerema', morphogenic gradients were apparent in shoot and leaf formation but not in root and somatic embryo formation. The embryonic axes attached to the cotyledons of cultivar`Schattenmorelle' had an inhibitory effect on morphogenesis.

The study was conducted to investigate the effects of different phosphorous levels on the growth ... more The study was conducted to investigate the effects of different phosphorous levels on the growth and seed yield of the lettuce (Lactuca sativa L.). Two lettuce varieties namely Grand Rapids and Romaine were tested on various phosphorus fertilizer levels i.e. 60 kg and 80 kg per hectare using Randomized Complete Block under factorial Design (RCBD). The treatment without phosphorus was seed parameters as well as sensory evaluation including crispiness and color were examined after interval of each 10 days. We report that the increase in the phosphorus fertilizer has positive effects on yield, ground cover and shelf life of both varieties; however Grand Rapids significantly showed superior performance than that of Romaine. Furthermore, Romaine developed seeds not observed in case of Grand Rapids cultivar seemingly due to insufficient chilling hours required for phase transition. Further investigations are suggested at molecular level to decipher the components involved in better yield and seed development in both varieties tested.

Genetics and Molecular Research, 2011

Activity and expression of polygalacturonase (PG), a hydrolytic enzyme involved in ultrastructura... more Activity and expression of polygalacturonase (PG), a hydrolytic enzyme involved in ultrastructural changes in the pericarp of sweet pepper (Capsicum annaum), were investigated at different ripening stages of the pepper cultivars Mandi and Talanduo. Molecular cloning of CaPG was carried out by constructing a cDNA library from three stages of fruit ripening. Morphological determination, PG assay, RT-PCR, and ultrastructural studies were used to quantify changes in CaPG gene expression in the pericarp from green, color change and fully ripened stages. We found that CaPG gene expression, PG activity and striking changes in the structure of the cell wall occurred with the transition of ripening stages. CaPG gene expression was high (obvious PCR products) in mature and ripened stages of both cultivars; however, the CaPG gene was not expressed in preclimacteric fruits or vegetative tissues. We conclude that developmental regulation of CaPG gene expression is instrumental for sweet pepper fruit ripening; its expression during ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 10 (4): 3275-3290 (2011) S.S. Ahmed et al. development leads to dissolution of middle lamella and eventually disruption of the fully ripened cell wall.

Tomato (Lycopersicon esculentum Mill) is edible, often red berry-type fruit and a rich source of ... more Tomato (Lycopersicon esculentum Mill) is edible, often red berry-type fruit and a rich source of Fe, Vitamin A, B and C. It is widely cultivated all over the world. E8 gene is related to ethylene biosynthesis in plants. Ethylene is responsible for growth and ripening of fruits. The present study was carried out to detect and amplify the E8 Promoter in the leaves and fruits of Tomato, Spring onion, Capsicum and Lettuce. The CTAB Protocol of Doyle and Doyle (1990) were used for DNA extraction from leaves and fruits and quality was checked on gel electrophoresis. PCR program for E8 was optimized and PCR products were sequenced. The sequencing results were aligned and Blast. The result indicated that in Tomato fruit the E8 gene is detected and amplified as compare to leaves and other plants. This E8 primer will be utilized for different fruits as well.

Genetics and Molecular Research, 2012

Molecular chaperones of plasmid pBI121 carrying CaMV35S promoter and a nucleotide sequence of pla... more Molecular chaperones of plasmid pBI121 carrying CaMV35S promoter and a nucleotide sequence of plasmid pBI221 were inserted into plasmid pCAMBIA2300 to construct an intermediate vector: pVBG2307. This novel vector pVBG2307 contains a greatly expanded multiple cloning site with an adjacent imported CaMV35S promoter sequence. This vector allows controlled transformation of DNA in both Escherichia coli and Agrobacterium tumefaciens. Cloned PG, orf456, ipt genes and E8, a fruiting promoter, were amplified by PCR of cDNA libraries of Capsicum annum and Lycopersicon esculentum and were then transferred into vector pVBG2307. The viability of this vector was demonstrated, as it regulated PG, orf456, ipt and E8 genes in E. coli and could be transferred into Agrobacterium strain EHA105-4.

Objective: To highlight the prevalence and epidemiology of New Delhi metallo-s-lactamase-1.produc... more Objective: To highlight the prevalence and epidemiology of New Delhi metallo-s-lactamase-1.producers in pus samples. Methods: The cross-sectional study was conducted from April to August 2018at the Biotechnology Laboratory, Balochistan University of Information Technology Engineering and Management Sciences, Quetta, Hi-tech Laboratory, Centre for Advance Studies in Vaccinology and Biotechnology, University of Balochistan, Quetta, and Microbiology Laboratory, Bolan Medical Complex Hospital, Quetta, Pakistan. Biochemical and molecular approaches were used for the identification of the isolates and Modified Hodge Test for the phenotypic detection of class-A carbapenemase activity. Minimum Inhibitory Concentration was performed using E-test and broth microdilution method. Molecular basis of carbapenemase activity was ascertained by the recognition of blaNDM-1 gene in the isolates. Results: Of the 300 pus samples taken from surgical/burn units,6(2%) blaNDM-1 harbouring isolates were foun...

Cloned elements of expression vector pBI121 carrying transcription initiation codon namelycaulifl... more Cloned elements of expression vector pBI121 carrying transcription initiation codon namelycauliflower mosaic virus section 35S and a nucleotide sequence NOS functioning transcription termination codon of cloning plasmid pBI221 were inserted into a precursor cloning plasmidpCAMBIA2300 to construct an intermediate vector termed as pVBG2307. Resultant vector pVBG2307 offers vast multiple cloning site with an adjacent imported CaMV35S promoter andtranscription stop codon sequences on its left border. This vector allows controlled transformation and regulation of nucleic acids in both E. coli and Agrobacterium tumefaciens. Many clonedCaPG, orf456, ipt genes and E8 (a fruiting promoter), were amplified from cDNA libraries of sweet pepper (Capsicum annum) and tomato (Lycopersicon esculentum) and were thentransferred into vector pVBG2307. The viability of this vector was demonstrated, as it regulated CaPG, orf456, ipt and E8 genes in Escherichia coli and could be transferred into tumor indu...

Methods in Molecular Biology, 2017

Plant cells respond to stresses and exogenous environmental stimuli. Production of altered levels... more Plant cells respond to stresses and exogenous environmental stimuli. Production of altered levels of reactive oxygen species (ROS) is one of a typical cellular responses against such stimuli. These responses are detectable through various techniques including luminol-based bioassays. Luminol-based bioassays provide an excellent opportunity for detection of ROS in plant leaf tissue when challenged with some exogenous stimuli like phytohormones, cytokinins, auxins, ABA, etc. The luminol-based protocol in point aims at measuring changes in the H2O2 levels of Arabidopsis leaf discs when exposed to phytohormone cytokinins. However, utility of the luminol-based ROS determination protocol is quite wide. We specifically optimized this protocol to quantify the effect of cytokinins on ROS production by Arabidopsis leaves.

Pakistan Journal of Zoology, 2016

Cloned elements of expression vector pBI121 carrying transcription initiation codon namely caulif... more Cloned elements of expression vector pBI121 carrying transcription initiation codon namely
cauliflower mosaic virus section 35S and a nucleotide sequence NOS functioning transcription
termination codon of cloning plasmid pBI221 were inserted into a precursor cloning plasmid
pCAMBIA2300 to construct an intermediate vector termed as pVBG2307. Resultant vector
pVBG2307 offers vast multiple cloning site with an adjacent imported CaMV35S promoter and
transcription stop codon sequences on its left border. This vector allows controlled transformation
and regulation of nucleic acids in both E. coli and Agrobacterium tumefaciens. Many cloned
CaPG, orf456, ipt genes and E8 (a fruiting promoter), were amplified from cDNA libraries of
sweet pepper (Capsicum annum) and tomato (Lycopersicon esculentum) and were then
transferred into vector pVBG2307. The viability of this vector was demonstrated, as it regulated
CaPG, orf456, ipt and E8 genes in Escherichia coli and could be transferred into tumor inducing
Agrobacterium strain EHA105-4.

We studied the efficiency of maintaining and restoring cytoplasmic male sterility (CMS) systems i... more We studied the efficiency of maintaining and restoring cytoplasmic male sterility (CMS) systems in pepper (Capsicum annuum L.). An Rf-linked molecular marker was employed to analyze the interaction between 6 CMS lines (A), 5 maintainers (B), and 6 restorers (C). Sterility was maintained in the matings of lines 201A x 200B, 203A x 200B, 206A x 200B, 200A x 201B, 206A x 201B, 200A x 202B, 200A x 203B, 200A x 206B, and 201A x 206B. All 6 restorers restored the fertility of lines 200A, 202A, 203A, and 204A, except that 213C could not restore the fertility of lines 200A and 204A. However, the 6 restorers had diverse restoring abilities in individual CMS lines. The Rf-linked molecular marker was amplified by PCR in lines 207C, 208C, and 213C. This DNA marker was only found in the F1 hybrids M39, M14, M19, M25, M13, M20, and M22. We conclude that the restorers 208C and 207C can transmit the Rf gene or the Rf-linked marker to F1 hybrids.

To elucidate how physiological and biochemical mechanisms of chilling stress are regulated by abs... more To elucidate how physiological and biochemical mechanisms of chilling stress are regulated by abscisic acid (ABA) pretreatment, pepper variety (cv. 'P70') seedlings were pretreated with 0.57 mM ABA for 72 h and then subjected to chilling stress at 10°/6°C (day/night). Chilling stress caused severe necrotic lesions on the leaves and increased malondialdehyde and H 2 O 2 levels. Activities of monodehydroascorbate reductase (DHAR), dehydroascorbate reductase, glutathione reductase, guaiacol peroxidase, ascorbate peroxidase, ascorbate, and glutathione increased due to chilling stress during the 72 h, while superoxide dismutase and catalase activities decreased during 24 h, suggesting that chilling stress activates the AsA-GSH cycle under catalase deactivation in pepper leaves. ABA ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 11 (4): 4063-4080 (2012) W.L. Guo et al.

Cytoplasmic male sterile line RC7 of Chinese cabbage produces mature anthers without pollen. To u... more Cytoplasmic male sterile line RC7 of Chinese cabbage produces mature anthers without pollen. To understand the mechanisms involved, we examined the ultrastructural changes during development of the microspores. Development of microspores was not affected at the early tetrad stage. During the ring-vacuolated period, some large vacuoles appeared in the tapetum cells, making them larger, extending to the anther sac center during the monocyte period. At the same time, the tapetum degenerated as the microspores aborted, resulting in pollen-deficient anthers. As a result, the locules collapsed and the anthers shriveled. The callose was degraded in the pollen walls; abnormal deposits of electrodense material gave rise to irregular spike-shaped structures, rather than the characteristic rod-like shape of the B7 bacula. The internal intine wall of RC7 was thinner than that of the B7 type. At the mitosis I microspore stage, the tapetum cells contained multiple plastids, with numerous small spherical plastoglobuli, and lipid bodies. Based on these observations, we suggest that RC7 abortion may be due to mutated genes that normally regulate development of the pollen wall
and cell walls in the RC7 line.

International Journal of Biology and Biotechnology, 2015

Journal of Applied and Emerging Sciences, 2016

Genetics and Molecular Research, 2012

American Journal of Botany, 1986

Genetics and Molecular Research, 2011

Genetics and Molecular Research, 2012

Methods in Molecular Biology, 2017

Pakistan Journal of Zoology, 2016