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251.
S. Bushra M. Aslam M.A. Aziz M. Ahmed 《Archives Of Phytopathology And Plant Protection》2013,46(2):205-214
This study was carried out to see the impact of Angoumois grain moth (AGM) on different cultivars of barley so that we must grow resistant variety of barley or improve those which are susceptible to it. Eggs of Sitotroga cerealella (Oliv.) were collected and reared in incubators available in Stored Product Entomology Laboratory, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, under temperature 27 ± 2°C and 60 ± 2% relative humidity. For the experiment, five different cultivars of barley; Sanober-96, Jau-83, Soorab-96, ICBA and Sterling were selected for AGM feed. After an interval of 30, 60 and 90 days of infestation, percentage damage and weight loss in grains were determined. After carrying out laboratory and field germination tests, viability of different cultivars were checked. Damage was maximum in variety Soorab (99.38%), which becomes susceptible while it was minimum in Sanober-96 (90.62%), which becomes resistant. Weight loss was maximum in variety Soorab (49.71%), which becomes susceptible and was minimum in Sanober-96 (45.32%), which becomes resistant. Damage was positively correlated with weight loss and negatively correlated with seed germination. In germination tests, on filter paper, maximum germination was found in variety Sterling (3%) which becomes resistant and it was minimum in ICBA which becomes susceptible (0%). In sand germination test, maximum seeds germinated in variety Sanober-96 (2%), and minimum seeds germinated in ICBA (0%). By calculating the percentage of losses of different cultivars, it was found that none of cultivars proved itself completely resistant or susceptible. 相似文献
252.
Buba Ibrahim Ahmed Aliya Abubakar Sani Yusuf Ringim Namwa Voncir 《Archives Of Phytopathology And Plant Protection》2013,46(7):650-658
Abstract Field experiments were carried out at the Teaching and Research Farm of the Abubakar Tafawa Balewa University, Bauchi during the rainy season of 2005. The study was carried out with sole objective of evaluating the efficacy of six selected plant materials (sweetsop, red pepper, garlic, neem, mahogany and gmalina) against the major insect pests of cowpea variety, Dan Sokoto. The experiment was laid down in randomised complete block design with seven treatments. Each treatment was replicated three times. The results of the study showed that all the plant materials used were significantly (p < 0.05) better than control where no plant material was used in controlling the population of B. tabaci, E. dolichi, M. sjostedti and C. tomentosicollis at 1, 2 and 3 days after application of the treatments. Similarly the effects of these plant materials on the number of seeds/pod showed a significant (p < 0.05) difference between plots treated with plant materials and control. On the grain yield of the crop, all the plant materials showed significant effect except mahogany and the control which were statistically similar. Furthermore, the order of level of control indicated that sweet sop has (70.7%), garlic (69.3%), neem (61.0%), red pepper (54.0%), ash (30.9%), and mahogany (3.5%). The result of the present finding therefore recommends the use of sweet sop, garlic and neem as they were found to be the most promising in the control of major cowpea insect pests. 相似文献
253.
Ahmed A. ElSharawy Guoyi Yang Xiaoping Hu 《Archives Of Phytopathology And Plant Protection》2013,46(8):646-663
Verticillium dahliae is one of the most important pathogens causing Verticillium wilt. We studied the characterisation of the genetic relationship between virulence, vegetative compatibility groups (VCGs) and inter-simple sequence repeat (ISSR). A total of 48 V. dahliae isolates, in which 16 are collected from different cotton growing regions in China and 4 isolates belonged to all known VCGs, are used. Half of them were found highly virulent. Mutants (565) were obtained using the nitrate non-utilising mutant. These mutants were grouped into three VCGs: VCG1 (27 isolates), VCG 2 (14 isolates) and VCG 3 (7 isolates). Use of ISSR indicated two main clusters that were related to VCG and virulence. Genetic diversity lineages were obviously correlated to VCGs and ISSRs according to their geographical origin, virulence and ISSR genetic variation. This study could be useful to design and develop effective management strategies beside for quarantine purposes on Verticillium wilt control. 相似文献
254.
M. Shamsul Ola Mohammed M. Ahmed Hatem M. Abuohashish Salim S. Al-Rejaie Abdullah S. Alhomida 《Neurochemical research》2013,38(8):1572-1579
Neurodegeneration is an early event in the diabetic retina which may lead to diabetic retinopathy. One of the potential pathways in damaging retinal neurons is the activation of renin angiotensin system including angiotensin II type 1 receptor (AT1R) in the diabetic retina. The purpose of this study was to determine the effect of telmisartan, an AT1R blocker on retinal level of brain derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF) and tyrosine hydroxylase (TH), glutathione (GSH) and caspase activity in the diabetic rats. The dysregulated levels of these factors are known to cause neurodegeneration in diabetic retina. Three weeks streptozotocin induced diabetic rats were orally treated or untreated with telmisartan (10 mg/kg/day). After 4 weeks of treatments, the levels of BDNF and GSH were found to be increased systemically in the sera as well as in the retina of diabetic rats compared to untreated rats as measured by enzyme-linked immunosorbent assay and biochemical techniques (p < 0.05). The caspase-3 activity in the telmisartan treated diabetic retina was decreased compared to untreated diabetic rats (p < 0.05). Western blotting experiments showed the expression levels of BDNF, CNTF and TH were increased compared to untreated diabetic rats (p < 0.05). Thus, our findings show a beneficial effect of AT1R blocker telmisartan in efficiently increasing neurotrophic support, endogenous antioxidant GSH content, and decreasing signs of apoptosis in diabetic retina. 相似文献
255.
Salma Kloula Ben Ghorbal Abdelwaheb Chatti Mohamed Marwan Sethom Lobna Maalej Mouadh Mihoub Sana Kefacha Moncef Feki Ahmed Landoulsi Abdennaceur Hassen 《Current microbiology》2013,67(1):112-117
The changes in lipid composition enable the micro-organisms to maintain membrane functions in the face of environmental fluctuations. The relationship between membrane fatty acid composition and UV-C stress was determined for mid-exponential phase and stationary phase Pseudomonas aeruginosa. The total lipids were obtained by dichloromethane/methanol (3:1) and were quantified by GC. The TLC analysis of phospholipids showed the presence of three major fractions phosphatidylethanolamine, phosphatidylglycerol, and cardiolipin. Significant modifications, as manifested by an increase of UFA, were obtained. Interestingly, this microorganism showed a remarkable capacity for recovery from the stressful effects of UV-C. 相似文献
256.
Bakr Mohamed El-Zawahry Omar Ahmed AzzamNagla Sameh Zaki Heba Mohamed Abdel-RaheemDalia Ahmed Bassiouny Mervat Mamdooh Khorshied 《Gene》2013
PTPN22 1858C>T gene polymorphism has been associated with several autoimmune disorders including alopecia areata. The aim of the current study was to investigate the effect of the inherited genetic polymorphism 1858C>T of PTPN22 gene on the predisposition to severe forms of alopecia areata and its effect on the response to DPC treatment. To achieve our aim, PTPN22 1858C>T genotyping was performed by PCR-based restricted fragment length polymorphism (PCR-RFLP) analysis. The study included 103 Egyptian patients with extensive alopecia areata treated by DPC. Hundred healthy age and sex matched blood donors were included in the current study as a control group. Results of genotyping showed that PTPN22 CT and TT mutant genotypes were significantly higher in AA patients compared to controls and conferred increase risk of AA (OR = 2.601, 95% CI = 1.081–6.255). Statistical comparison between AA patients with wild and mutant genotypes revealed that the duration of the illness was significantly longer in those harboring the mutant genotypes. Moreover, the association of other autoimmune diseases as atopy and diabetes mellitus was higher in patients with mutant genotypes. Furthermore, PTPN22 1858C>T genetic polymorphism did not affect the patients' response to DPC immunotherapy. 相似文献
257.
Amal S. El-Shal Sally M. Shalaby Nader M. Aly Nearmeen M. Rashad Ahmed M. Abdelaziz 《Molecular biology reports》2013,40(11):6063-6073
Obesity, insulin resistance, and hyperandrogenism are considered crucial parameters of polycystic ovary syndrome (PCOS) which might be related to vitamin D metabolism. The aim of this study was to investigate the associations between polymorphisms (TaqI and ApaI) in the vitamin D receptor gene (VDR) and PCOS among Egyptian women. We aimed also to elucidate the impact of these polymorphisms on vitamin D level, hormonal and metabolic parameters of PCOS. One hundred and fifty Egyptian women with PCOS and 150 unrelated controls were enrolled in this study. Polymorphisms of VDR Taq-I T/C (rs731236) and Apa-I A/C (rs7975232) gene were genotyped using polymerase chain reaction restriction fragment length polymorphism (PCR–RFLP). Serum 25 hydroxy vitamin D [25(OH) D] levels were measured by high-performance liquid chromatography. PCOS women had significantly lower levels of 25(OH) D compared to healthy women. Our results revealed that Taq-I CC genotype and C allele were associated with increased risk of PCOS, while the Apa-I polymorphism was not. Haplotype Taq-I C/ Apa-I C was associated with a higher PCOS risk more than controls. Moreover, there was a significant decrease of 25(OH) D levels in carriers of haplotype Taq-I C/ Apa-I C (with variant alleles) compared to the non-carriers. Results showed also that there was an obesity- VDR Taq-I genotypes interactions. These results suggested that, VDR Taq-I gene polymorphism is associated with increased risk of PCOS in Egyptian women. 相似文献
258.
Margret Rave-Fränk Ihtzaz Ahmed Malik Hans Christiansen Naila Naz Sadaf Sultan Ahmad Amanzada Martina Blaschke Silke Cameron Shakil Ahmad Clemens Friedrich Hess Giuliano Ramadori Federico Moriconi 《Radiation and environmental biophysics》2013,52(3):321-338
The liver is considered a radiosensitive organ. However, in rats, high single-dose irradiation (HDI) showed only mild effects. Consequences of fractionated irradiation (FI) in such an animal model have not been studied so far. Rats were exposed to selective liver FI (total dose 60 Gy, 2 Gy/day) or HDI (25 Gy) and were killed three months after the end of irradiation. To study acute effects, HDI-treated rats were additionally killed at several time points between 1 and 48 h. Three months after irradiation, no differences between FI and HDI treatment were found for macroscopically detectable small “scars” on the liver surface and for an increased number of neutrophil granulocytes distributed in the portal fields and through the liver parenchyma. As well, no changes in HE-stained tissues or clear signs of fibrosis were found around the portal vessels. Differences were seen for the number of bile ducts being increased in FI- but not in HDI-treated livers. Serum levels indicative of liver damage were determined for alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (γGT) and lactate dehydrogenase (LDH). A significant increase of AP was detected only after FI while HDI led to the significant increases of AST and LDH serum levels. By performing RT-PCR, we detected up-regulation of matrix metalloproteinases, MMP-2, MMP-9, MMP-14, and of their inhibitors, TIMP-1, TIMP-2 and TIMP-3, shortly after HDI, but not at 3 month after FI or HDI. Overall, we saw punctual differences after FI and HDI, and a diffuse formation of small scars at the liver surface. Lack of “provisional clot”-formation and absence of recruitment of mononuclear phagocytes could be one explanation for scar formation as incomplete repair response to irradiation. 相似文献
259.
260.