Advancements in Life Sciences, volume 3, issue 1
Published online: 25-November-2015
ISSN 2310-5380
IN THIS ISSUE
Review Articles:
Development of herbicide resistant crops through induced mutations
Muhammad Rizwan, Sajjad Akhtar, Muhammad Aslam, Muhammad Jawad Asghar, pages 01-08
Read Abstract Herbicide resistance is an innate characteristic of crop plants. It enables them to survive and propagate even in the presence of lethal doses of herbicides in the surroundings. Genetic tolerance in crops towards herbicides may have several benefits. It may increases safety margins between weed and crop sensitivity and also expands applicability of a particular herbicide. Besides, it can also lower the operating cost for weed control as compared to manual weeding and crop rotation which is normally prohibited by herbicide persistence. Herbicide resistant crops are developed through transformation of a plant with either native or mutant resistant genes, seed mutagenesis, plant cell or tissue culture and through other traditional plant breeding techniques. Seed mutagenesis is a non-transgenic approach, which is found to be most economical and perfect approach. Moreover, all commercial herbicide tolerant crops were derived from single nucleotide substitution of genes and trait can be incorporated into elite varieties because of incomplete dominance and non-pleiotropic effect of the alleles of all commercial herbicide tolerant mutations.
Full Length Research Articles:
Sensory and histamine assessment of the freshness of Sardine (Sardine sindensis) during different storage conditions
Rozina Sardar, Sohail Hassan Khan, Zafar Tanveer, pages 09-15
Read Abstract Background: Storage of fish under refrigerated conditions from the time it is caught until when it is consumed has been found to be very important in reducing outbreaks of histamine poisoning. Methods: Low temperatures control bacterial histamine formation during fish processing. The shelf life of sardine (sardine sindensis) during storage at ambient temperature (33°C), ice box temperature (0°C) and freezing temperature (-7°C) were studied in terms of sensory and histamine production. The sensory acceptability limit was up to one day at ambient temperature and 11 days at ice storage condition. However, freezing storage had a good preserving effect on sensory acceptability at the end of experiment. The formation of histamine was determined at day 0, 1, 2, 3, 4, 7, 8, 9, 11, 14, 16 and 18 of experiment using high performance liquid chromatography (HPLC) fluorometeric method. Results: Histamine development had not exceeded the permissible level (200 mg/kg) recommended by the FAO (2012) during storage condition at -7°C throughout the experiment. At 0°C, histamine concentration was lower than safe level for up to 16 days (135 mg/kg). At ambient temperature, the sardine was spoiled on 3rd day and histamine concentration was found 500.48 mg/kg which was above the FAO recommended level for histamine. Conclusion: Freezing storage condition has a good preserving effect on sensory acceptability and histamine production and seems the best means of storage.
Molecular confirmation of Bdv2 gene in wheat germplasm and its field based assessment for resistance against barely yellow dwarf viruses
Samra Kausar, Shahid Hameed, Irfan ul Haque, Kamran Saleem, Madiha Zamurrad, Muhammad Ashfaq, pages 16-22
Read Abstract Background: Barley yellow dwarf in wheat is an important viral disease among wheat cultivating areas of the world. It is gradually progressing as a major threat to wheat crop in Pakistan due to availability of favorable environmental conditions. The use of resistant cultivar is environmentally safest method for disease control so, it is necessary to develop resistant cultivars before epidemic outbreaks. Methods: The most commonly used wheat variety Inqilab91 was crossed with BYDV / CYDVresistant variety TC14. F1 generation obtained from the P1 cross was then allowed to self-cross. 61 plants were selected from F2 generation on the basis of disease tolerance or susceptibility and only tolerant plants were included for further experiments in the study. The presence of BDV2 among F2 generation was confirmed by sequence characterized amplified region (SCAR) markers in 6 (91, 96, 110, 119, 121 and 131) out of 61 genotypes which were then backcrossed with recurrent parent. Advance analysis regarding the presence of resistance source among the selected F2 generation was carried out using ELISA. Moreover, appearance of symptoms, agronomic values for different parameters, green house and field responses were also kept under consideration to characterize and confirm the presence of BDV2 among plants. Results: Results indicated that majority of F2 segregating population showed less yellowing, low viral titer and good agronomic values. ELISA value, glasshouse and field analysis showed that seven genotypes (30, 81, 89, 91,101,110 and 121) were resistant, and twenty-four genotypes were found moderately resistant. Tolerance was detected in genotypes 31, 47, 48, 50, 52, 56, 57, 60, 61, 94, 103, 106, 113, 115, 127, 140 and 413. Conclusion: Wheat lines containing Bdv2 genes showed resistance in both field and glasshouse. These wheat germplasm could be used as a source of resistance in CDRP-NARC for the further development of resistant wheat varieties against BYDV / CYDV.
Effects of chronic mild stress on apomorphine induced behavioral sensitization in different brain regions of rats in relation to serotonin change
Muhammad Farhan, Darakshan Jabeen Haleem, pages 23-28
Read Abstract Background: The impacts of unpredictable stressors have influence on neurochemical and behavioral parameters in laboratory animals. Stress induced behavioral changes particularly those associated with anxiety like behavior may activate topographically organized mesolimbic cortical serotonergic system. This study was designed to investigate the influence of unpredictable stress on behavioral and neurochemical parameters in apomorphine treated rats. Methods: Initially, the animals were divided into two groups as Unstressed and stressed (uncontrollable chronic mild stress or UCMS). Both groups of animals were subdivided into two groups; i.e. saline and apomorphine administrated animals at dose 1.0 mg/kg. Behavioral manipulations was observed by monitoring the locomotor activity and exploratory activity. Neurochemical estimation of 5-hydroxytryptamine (5-HT) was done by High performance liquid chromatography (HPLC). Animals were decapitated 24hr post apomorphine injection and different regions of brain (dorsal and ventral striatum), of animals were collected and stored at -70°C. Results: This preclinical study showed that the UCMS induced hypophagia were promoted in apomorphine administrated animals. Apomorphine induced hyperlocomotion were more prominent in unstressed animals than that of stressed groups. It implies that apomorphine is effective in the retrieval from UCMS induced depressive symptoms in rats. Neurochemical study showed decreased level of 5-HT in unstressed animals than stressed animals in response to apomorphine administration. Conclusion: This study, therefore establish the relation between stress and addiction at behavioral as well as neurochemical level to better understand the idea whether intolerable stress promotes addiction.
Selection of potent bacterial strain for over-production of PHB by using low cost carbon source for eco-friendly bioplastics
Rahat Abdul Rehman, Abdul Qayyum Rao, Zahoor Ahmed, Ambreen Gul, pages 29-35
Read Abstract Background: The microbial PHB production is a promising tool for the plastic industry for the synthesis of environmental friendly, biodegradable plastic in contrast to the conventional petro-chemical based non-degradable plastics. The selection of potent bacterial strains, inexpensive carbon source, efficient fermentation and recovery processes are important aspects that were taken into account during this study. Methods: Different bacterial strains i.e. Bacillus Spp, P. putida and P. fluorescens were screened for maximum PHB production. Under media optimization, various carbon and nitrogen sources (alone or in combination) were used to achieve the maximum PHB production. Finally the degradation tests of the PHB sheet were also performed to test its biodegradability potential. Results: Shake flask studies have shown the PHB concentrations upto 7.02, 4.50 and 34.4 mg/g of dry cell mass of P. putida, P. fluorescens and Bacillus Spp. respectively. Almost same results were observed at laboratory scale production of PHB in 10 L fermenter i.e. 6.28, 6.23 and 39.5 mg/g of dry cell mass by P. putida, P. fluorescens and Bacillus Spp. respectively. On the basis of these observations, Bacillus Spp. was chosen for laboratory scale PHB production. Corn steep liquor (4%) was chosen as the best medium to achieve the highest PHB contents. Isolated PHB has shown biodegradation in soil up to 86.7% at 37oC. Conclusion: The Bacillus Spp. Proved to be the best strain for PHB production on only 4% CSL which is cheapest and easily available.
