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91.
Chinmay Biswas Piyali Dey Subrata Satpathy Manoj Kumar Pratik Satya B. S. Mahapatra 《Phytoparasitica》2013,41(5):539-543
Mesta (Hibiscus sabdariffa) is an important bast fiber crop. In August 2011, there was an outbreak of a phytoplasma-like disease on H. sabdariffa in different villages of the northern coastal mesta-growing region of Andhra Pradesh, India, covering mainly two districts – Srikakulam and Vijayanagaram. The infected plants showed characteristic symptoms such as phyllody and reddening of leaves. PCR with P1/P7 universal primer pair of 16 S rDNA yielded amplicons of 1850 bp from all symptomatic mesta leaf samples similar to samples of brinjal little leaf (phytoplasma positive reference control). However, asymptomatic samples were not amplified. Multiplex nested-PCR showed simultaneous amplification of DNA fragments with phytoplasma specific primers, viz., P1/P7 universal primer pair of 16 S rDNA, nested primer pair R16F2n/R2, uvrB and DegV gene-specific uvrB-degVF/R primer generating amplicons of 1850 bp, 1200 bp and 1023bp, respectively. However, SecY-map gene specific primer SecY-mapF/R was not amplified. The 1023 bp nucleotide sequence of uvrB and DegV gene of the phytoplasma was deposited in the GenBank (NCBI) with the accession no. JX975061. NCBI BLASTn analysis of the 1023 bp products showed that the phytoplasma strain belonged to elm yellows group (16SrV-D). This is the first report that Hibiscus sabdariffa is infected by a phytoplasma and we named it mesta phyllody disease (MPD). 相似文献
92.
Aritra Saha Pabitra K. Mani Gora Chand Hazra Arup Dey Shubhadip Dasgupta 《Journal of plant nutrition》2013,36(16):2091-2102
AbstractCritical values of boron (B) for wheat nutrition in soil and plant were determined through a pot experiment with twenty-one surface soils of Alluvial flood plain and Red-latertic belt comprising three major soil orders (Entisols, Alfisols, Inceptisols) with four levels of boron. Application of boron significantly increased the dry matter yield as well as uptake of B by plants. Critical concentration of hot calcium chloride (CaCl2) extractable B in soil for wheat was found to be 0.53?mg?kg?1. The critical plant B concentration varied with growth stages and values were 7.4?mg?kg?1 at panicle initiation and 4.18?mg?kg?1 at maturity, respectively. The findings of this investigation also recommend the application of 2?kg?B?1?ha?1 for ensuring B sufficiency to wheat in Indo-gangetic alluvial and Red-Lateritic soils. 相似文献
93.
Aissaoui Fatima Hedjal-Chebheb Mariam Soltani Abir Haouel-Hamdi Soumaya Talhi Oualid Ziani Borhane Eddine Chérif Mediouni-Ben Jemâa Jouda 《植物病害和植物保护杂志》2021,128(5):1167-1176
Journal of Plant Diseases and Protection - The aims of this work were to point out the seasonal variation in chemical composition and evaluate the insecticidal activities of Mentha spicata and... 相似文献
94.
SummaryThe present study was undertaken over two consecutive years under sub-temperate climatic conditions in the mid-hill region of Himachal Pradesh (30°52'N, 77°11'E; 1,175 m asl) on loamy sand Inceptisols. The aim was to investigate the effects of irrigation and mulch material on the growth, flowering, fruiting behaviour, relative leaf water content (RLWC), yield, and quality of strawberry (Fragaria × ananassa L. ‘Chandler’). The drip irrigation treatments included irrigation with 100, 80, or 60% (coded 1.0, 0.8, and 0.6 V) of the total water requirement. Both mulches increased the minimum soil temperature to a depth of 5 cm. The drip and surface irrigation treatments raised the minimum soil temperature by 3.0º – 5.4ºC, and lowered the maximum temperature by 2.2º – 5.8ºC compared to the rainfed control. Hay mulch was more effective in raising the minimum temperature and lowering the maximum soil temperature than black polyethylene mulch. Moisture conservation increased by 2.8 – 12.8% under the black polyethylene mulch compared to the no-mulch treatment. Drip and surface irrigation methods, as well as mulching, were found to be effective for enhancing the growth, irrigation water use efficiency (IWUE), fruit yield, and quality of strawberry plants. However, the number of crowns per plant, the percentage berry set, the RLWC, root length density (RLD), and fruit yield were highest under treatment M3I3 [i.e., black polyethylene mulch plus drip irrigation (1.0 V)] by 565.5%, 94.5%, 32.8%, 394.5%, and 549.6%,respectively, compared to the no mulch plus rainfed control. The maximum IWUE values for plant biomass [1.39 metric tonnes (MT) ha–1 m–1] and fruit yield (2.79 MT ha–1 m–1) were recorded under treatment M3I5 [i.e., black polyethylene mulch plus drip irrigation (0.6 V)]; whereas, the lowest values (0.39 and 0.68 MT ha–1 m–1, respectively) were observed using treatment M1I2 (i.e., without mulch, plus surface irrigation). Fruit size, weight, sugar content, and anthocyanin content increased significantly under treatment M2I3 [i.e., hay mulch, plus drip irrigation (1.0 V)] compared with all other treatments. Total soluble solids (TSS) contents and total acidity (TA) were highest under treatment M1I1 (i.e., no mulch, plus rainfed). A linear regression model could describe the variations in quality parameters of strawberry plants grown under sub-temperate climatic conditions. Root density was found to be the best indicator with which estimate fruit quality. 相似文献
95.
Genetic analysis of important antioxidant compounds in cabbage (Brassiaca oleracea var. capitata L.)
Chander Parkash Sandeep Kumar Nisha Thakur Satish Kumar S. S. Dey Reeta Bhatia 《Journal of Crop Improvement》2017,31(3):418-437
The paucity of research on development of antioxidant-rich hybrids in cabbage by utilizing combining ability estimates, gene action, and heterosis motivated us to undertake this study. We made 60 crosses between 5 cytoplasmic male-sterile lines and 12 male-fertile testers during the summer of 2015, as per the line × tester design. The seedlings of all the parents and 60 F1 crosses, along with three checks, were transplanted during the Rabi (winter) season of 2015–2016 and evaluated using a randomized complete-block design. Combining ability, gene action, and heterosis were determined for different antioxidant compounds. Experimental results revealed that the range of cupric ion reducing antioxidant capacity (CUPRAC) [parents = 1.26–7.33 and hybrids = 0.04–6.54 μmol trolox/g], ferric reducing ability of plasma (FRAP) [parents = 1.65–4.76 and hybrids = 0.16–4.67 μmol trolox/g], β-carotene (parents = 0.44–2.29 and hybrids = 0.04–1.89 μg/100 g), and chlorophyll-a (parents = 0.71–4.08 and hybrids = 0.19–3.08 mg/g f.w.) for hybrids was lower than that of the parents because of outbreeding depression. The parental lines 6A, 208A, 83-5-8, and Sel-5-83-6 were found to be good general combiners for most of the antioxidant compounds studied. Based on the mean performance, specific combining ability effects and heterosis, five hybrid combinations viz., 9A × KIRC-8 for CUPRAC and FRAP; 208A × C-122 for ascorbic acid; 6A × Chhaki-2 for total carotenoids and β-carotene; 831A × Chhaki-2 for chlorophyll-a; and 6A × 83-5-8 for chlorophyll-b and total chlorophyll content, were most promising. The ratio of general combining ability (GCA) and specific combining ability (SCA) variances, i.e., [2 σ2g/(2σ2g + σ2s)], which reflects the relative importance of GCA versus SCA, was less than unity for different antioxidant compounds, which implied that for these traits, nonadditive gene effects were more important than additive effects. The numerical values of range for contribution of lines × testers interaction for different traits (41.47–70.18%) were found to be higher than the individual contribution of lines (11.24–47.22%) and testers (8.31–21.76%). Hence, heterosis could be exploited for developing antioxidant-rich hybrid cabbage. 相似文献
96.
Impact of the Community‐based Fish Culture System on Expenditure and Inequality: Evidence from Bangladesh 下载免费PDF全文
A. B. M. Mahfuzul Haque Madan Mohan Dey 《Journal of the World Aquaculture Society》2016,47(5):646-657
This study investigated the impact of a Community‐based Fish Culture (CBFC) system on household expenditure and how expenditure inequality in the fish‐producing communities has changed due to involvement in the CBFC system. Six floodplains, comprising three project sites and three controls, were chosen from three river basin areas of Bangladesh; data for this study were collected for a period of 3 yr. A propensity score matching method was used to evaluate the impact of CBFC on household expenditure; while a Gini coefficient and Gini decomposition were used to estimate inequality. The results show that the CBFC system has a positive and significant impact on fish culture community household expenditure. Results also reveal that the CBFC system has an equalization effect on food, clothing, and healthcare expenditure. Furthermore, this management system helps to distribute total expenditure 15% more equally among the fish culture communities. 相似文献
97.
Ghosh Arkendu Dey Koyel Hassan Md. Abu Bauri Fatik Kumar Das Bikash Chandra Bhowmick Nilesh Dey Amarendra Nath Das Soumitra Sahu Pradip Kumar 《Genetic Resources and Crop Evolution》2022,69(7):2585-2604
Genetic Resources and Crop Evolution - Semecarpus anacardium L. is a potential underutilized edible, highly nutritious fruit crop with ample medicinal properties grown in some localized pockets of... 相似文献
98.
A velogenic Newcastle disease virus isolate typed to belong to group C1 by monoclonal antibody typing was adapted 50 times
in chicken embryo fibroblast cell culture and 60 times in Vero cells. At every 10th passage the virus was characterized on
the basis of mean death time, intracerebral pathogenicity indices and viral titration studies. A gradual reduction in the
virulence of the virus was noted as the passage number increased. RT-PCR of a 254 bp region of the fusion gene encompassing
the fusion protein cleavage site was carried out for the virulent as well as cell culture-adapted viruses at every 10th passage
level. The amplicons were subsequently digested with three restriction enzymes, viz. AluI, HaeIII and PstI. It was found out that there was difference in banding patterns between the virulent and adapted viruses, indicating nucleotide
substitutions in the virulent virus when it was sequentially passaged onto cell culture systems. 相似文献
99.
Philip JY Da Cruz Francisco J Dey ES Buchweishaija J Mkayula LL Ye L 《Journal of agricultural and food chemistry》2008,56(20):9350-9354
Solvent extracted cashew nut shell liquid (CNSL), conventionally known as natural CNSL, is a mixture of several alkenyl phenols. One of these alkenyl phenols is anacardic acid, which is present at the highest concentration. In view of anticipated industrial applications of anacardic acid, the objective of this work was to isolate anacardic acid from natural CNSL by supercritical carbon dioxide (scCO 2). In this study, the solubility data for natural CNSL in scCO 2 under a range of operating conditions of pressure (100, 200, and 300 bar), temperature (40 and 50 degrees C), and CO 2 flow rate (5, 10, and 15 g min (-1)) were established. The best scCO 2 working conditions were found to be 50 degrees C and 300 bar at a flow rate of 5 g min (-1) CO 2. Using 3 g of sample (CNSL/solid adsorbent = 1/2) under these scCO 2 conditions, it was possible to quantitatively isolate high purity anacardic acid from crude natural CNSL (82% of total anacardic acid) within 150 min. The anacardic acid isolated by scCO 2 was analyzed by different spectroscopic techniques (UV-vis, FT-IR, and (1)H NMR) and HPLC analysis, indicating that the anacardic acid isolated by scCO 2 has better quality than that obtained through a conventional method involving several chemical conversion steps. 相似文献
100.
Fire affects the physical and chemical properties and soil biological activity of natural ecosystems. This study was conducted in the Miyan Tang region, Ilam Province in western Iran. The study site was 110 hectares, where we sampled soils in areas that were classified by fire severity: low (LS), high (HS) and medium severity (MS), and unburned (UB), which served as the control. In each severity class, 25 transect points were randomly selected for measurement. Around each transect plot center, 3 soil samples were selected randomly and soils collected from the 0 to 20 cm depth were combined into a composite sample that was used in laboratory analysis to represent conditions at that point. Plots in the UB and LS fire classes had similar soil conditions and had higher values of factors such as saturated moisture, organic carbon, carbon dioxide, and silt and clay content. In contrast, plots in the HS and MS fire severity classes were clustered in the positive direction along the first axis that represented gradients in soil acidity, electrical conductivity, cation exchange capacity, accessible phosphorus, accessible potassium, bulk density, and sand. Soil attributes were similar in areas of HS and MS fire severity classes, whereas soil conditions in the LS class and UB controls were most similar. Fire in the LS areas either did not significantly alter the physical–chemical soil properties and microbial basal respiration, or soils were able to recover quickly after being burned. 相似文献