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61.
Globally among biotic stresses, diseases like blight, rust and blast constitute prime constraints for reducing wheat productivity especially in Bangladesh. For sustainable productivity, the development of disease-resistant lines and high yielding varieties is vital and necessary. This study was conducted using 122 advanced breeding lines of wheat including 21 varieties developed by Bangladesh Wheat and Maize Research Institute (BAMRI) with aims to identify genotypes having high yield potential and resistance to leaf blight, leaf rust and blast diseases. These genotypes were evaluated for resistance against leaf blight and leaf rust at Dinajpur and wheat blast at Jashore under field condition. Out of 122 genotypes tested, 20 lines were selected as resistant to leaf blight based on the area under the diseases progress curve (AUDPC) under both irrigated timely sown (ITS) and irrigated late sown (ILS) conditions. Forty-two genotypes were found completely free from leaf rust infection, 59 genotypes were identified as resistant, and 13 genotypes were identified as moderately resistant to leaf rust. Eighteen genotypes were immune against wheat blast, 42 genotypes were categorized as resistant, and 26 genotypes were identified as moderately resistant to wheat blast. Molecular data revealed that the 16 genotypes showed a positive 2NS segment among the 18 immune genotypes selected against wheat blast under field conditions. The genotypes BAW 1322, BAW 1295, and BAW 1203 can be used as earlier maturing genotypes and the genotypes BAW 1372, BAW 1373, BAW 1297 and BAW 1364 can be used for lodging tolerant due to short plant height. The genotypes WMRI Gom 1, BAW 1349 and BAW 1350 can be selected for bold grain and the genotypes WMRI Gom 1, BAW 1297, BAW 1377 can be used as high yielder for optimum seeding condition but genotypes BAW 1377 and BAW 1366 can be used for late sown condition. The selected resistant genotypes against specific diseases can be used in the further breeding program to develop wheat varieties having higher disease resistance and yield potential.  相似文献   
62.
Tristeza is a devastating viral disease in all the citrus growing countries throughout the world and has killed millions of citrus trees in severely affected orchards. The citrus species grafted on sour orange rootstock are affected by this disease. Predominantly, the sweet orange, grapefruit and lime trees grafted on sour orange exhibit severe symptoms like quick decline, vein clearing, pin holing, bark scaling and degeneration leading to variable symptoms. Symptomatic expression of Citrus tristeza virus (CTV) in different hosts has been attributed to virus isolates which are from severe to mild. Different serological and molecular assays have been deployed to differentiate the strains of CTV. Citrus tristeza virus is diversified towards its strains on the basis of biological, serological and molecular characterization. Phenotypic expression is due to genetic alteration and different molecular basis have now been adopted for strain differentiation. This review will give a brief idea about the different CTV isolates, their characterization based on nucleic acid and serological assays. Different methods along with salient features for strain characterization has also been reviewed. This review will also open the new aspects towards formulation of management strategies through different detection techniques.  相似文献   
63.
Plant and Soil - Success in agronomic biofortification of maize and wheat is highly variable. This study aimed to elucidate the differences in uptake and translocation of foliar-applied zinc (Zn)...  相似文献   
64.
65.
The length-weight relationships (LWRs) of six Nemacheilid species (Schistura chindwinica, S. fasciata, S. khugae, S. minuta, S. reticulata and S. rubrimaculata) have been analyzed. Fish samples were collected on quarterly basis from March 2018 to February 2019. Sampling was performed using cast nets (mesh size 5–10 mm; about 50 sq m area covered each time and water depth was 4 ft approx.), and electrofishing (Ultrasonic Inverter Electro Fisher, 24 volts, 4 m) in the day time. The total length (TL) of individual fish was measured to 0.1 cm with a digital caliper and body weights (BW) were measured to 0.001 g with digital electronic balances. The parameters for the LWR equations were calculated, and the respective statistics such as the 95% confidence interval for parameters “a” and “b” are provided as well as the coefficient of correlation. For five species a new maximum total length has been documented.  相似文献   
66.
Molecular Biology Reports - Hepatocellular carcinoma (HCC) is the most common primary liver cancer characterized by dysregulation of several crucial cellular signaling pathways such as...  相似文献   
67.

Non-albicans Candida species and other rare yeasts have emerged as major opportunistic pathogens in fungal infections. Identification of opportunistic yeasts in developing countries is mainly performed by phenotypic assay, which are time-consuming and prone to errors. The aim of the present study was to evaluate PCR-RFLP as a routinely used identification technique for the most clinically important Candida species in Iran and make a comparison with a novel multiplex PCR, called 21-plex PCR. One hundred and seventy-three yeast isolates from clinical sources were selected and identified with sequence analysis of the D1/D2 domains of rDNA (LSU rDNA) sequencing as the gold standard method. The results were compared with those obtained by PCR-RFLP using MspI restriction enzyme and the 21-plex PCR. PCR-RFLP correctly identified 93.4% of common pathogenic Candida species (C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, and P. kudriavsevii (=?C. krusei)) and was able to identify 45.5% of isolates of the uncommon yeast species compared to the D1/D2 rDNA sequencing. Compared with PCR-RFLP, all common Candida species and 72.7% of uncommon yeast species were correctly identified by the 21-plex PCR. The application of the 21-plex PCR assay as a non-sequence-based molecular method for the identification of common and rare yeasts can reduce turnaround time and costs for the identification of clinically important yeasts and can be applied in resource-limited settings.

  相似文献   
68.
Archives of Microbiology - Severe acute respiratory syndrome virus 2 (SARS-CoV-2) belongs to the single-stranded positive-sense RNA family. The virus contains a large genome that encodes four...  相似文献   
69.
Neurochemical Research - Alzheimer's disease (AD) is age-dependent neurological disorder with progressive loss of cognition and memory. This multifactorial disease is characterized by...  相似文献   
70.
Journal of Plant Growth Regulation - Plant biofibers are of great economic and commercial importance. Among various fiber producing crops, cotton (Gossypium hirsutum L.), hemp (Cannabis sativa L.),...  相似文献   
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