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Molecular and Biological Studies of Papaya Ringspot Virus Isolates from Brazil and Cuba
Douglas Rodríguez Martínez,
Priscilla de Sousa Geraldino Duarte,
Justo González Olmedo,
Antonia dos Reis Figueira
Issue:
Volume 2, Issue 5, September 2014
Pages:
209-218
Received:
6 August 2014
Accepted:
19 August 2014
Published:
30 August 2014
Abstract: The coat protein genes of 21 Papaya ringspot virus (PRSV) isolates from Brazil and 7 isolates from Cuba were sequenced and analyzed, and the symptoms induced by the virus isolates were evaluated in papaya (Carica papaya L. cv. Solo) and squash (Cucurbita pepo L. cv. Caserta). The virus isolates were grouped in phylogenetic trees by geographic region, presenting the highest nucleotide and amino acid identities with those isolates collected in the same regions. The American and Indian isolates, from GenBank were grouped together in the tree, and the Brazilian isolates were grouped by state; the Cuban isolates from the eastern region were closer to the American isolates than to those from the central-west region. Typical mosaic symptoms, grouped according to intensity, were observed in the inoculated papaya and squash seedlings. The variability of the coat protein genes confirmed that virus control using cross-protection and transgenic plants requires the selection of region-specific virus isolates in each country.
Abstract: The coat protein genes of 21 Papaya ringspot virus (PRSV) isolates from Brazil and 7 isolates from Cuba were sequenced and analyzed, and the symptoms induced by the virus isolates were evaluated in papaya (Carica papaya L. cv. Solo) and squash (Cucurbita pepo L. cv. Caserta). The virus isolates were grouped in phylogenetic trees by geographic regio...
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Optimization of Fermentation Medium Compositions from Dewatered Wastewater Sludge of Beer Manufactory for Bacilus Thuringiensis Delta Endotoxin Production
Nguyen Thi Hoa,
Tang Thi Chinh,
Dang Thi Mai Anh,
Ngo Dinh Binh,
Le Thi Minh Thanh
Issue:
Volume 2, Issue 5, September 2014
Pages:
219-225
Received:
11 August 2014
Accepted:
28 August 2014
Published:
10 September 2014
Abstract: Optimization of medium compositions from dewatered wastewater sludge of beer manufactory for delta endotoxin production by Bacillus thuringiensis was investigated in flask fermentation. Its composition consisted of wastewater sludge hydrolysis broth with several agricultural byproducts (rice bran, soybean meal, corn flour) and mineral salts (MgSO4.7H2O; K2HPO4; KH2PO4; MnSO4; CaCl2; NaCl). Rice bran and MgSO4.7H2O, CaCl2 were all found to have a significant influence on delta endotoxin production. The optimal concentration of these three factors were then sequentially investigated using the response surface methodology with a central composite design. The resulting optimal medium components for delta endotoxin production were determined as follows: WWS (20 g/l, dry weight), CaCl2 (0.3 g/l), MgSO4.7H2O (0.32 g/l), and rice bran (5.8 g/l). Using this optimized fermentation media, the yield of delta endotoxin was increased by 34% to 565 mg/l compared with unoptimal medium. Viable cell and spore counts obtained in optimum fermented broth were 1.25x109 CFU/ml, 1.07x109 CFU/ml, respectively. The LC50 value of Bacillus thuringiensis serovar isralensis against Culex quinquefasciatus was 0.056 mg/l and there was no significant difference between LC50 value of bacterium grown in the medium.
Abstract: Optimization of medium compositions from dewatered wastewater sludge of beer manufactory for delta endotoxin production by Bacillus thuringiensis was investigated in flask fermentation. Its composition consisted of wastewater sludge hydrolysis broth with several agricultural byproducts (rice bran, soybean meal, corn flour) and mineral salts (MgSO4....
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Pollen Analysis of Apis mellifera Honey Collected from Nigeria
Joshua Kayode,
Sunday Dele Oyeyemi
Issue:
Volume 2, Issue 5, September 2014
Pages:
226-231
Received:
23 August 2014
Accepted:
3 September 2014
Published:
20 September 2014
Abstract: Pollen analyses of twelve honey samples collected in two successive years (2011-2012) from different towns and villages in Ekiti State, South western Nigeria were carried out in order to ascertain their pollen compositions. The results from the analysis revealed eighty-five taxa belong to thirty-three botanical families. Of these, thirty-two were identified to generic level and forty-five plants were identified to the specific level. The number of pollen grains in the honey samples varied significantly (between 4,818 - 85,087 pollen grains), indicating their richness in pollen grains. Also in this study, some important honey plants such as Spondias mombin, Alchornea cordifolia, Lannea sp, Asteraceae, Alchornea sp, Rubiaceae, Elaeis guineensis, Pavetta sp, Oldenlandia corymbosa, Triplochiton scleroxylon, Mimosops warneckii, Blighia sapinda, Piptadeniastrum africanum, Entada gigas, Tithonia diversifolia, and Combretaceae/Melastomataceae have been identified to be characteristics of vegetation typical of Ekiti State and reflection of common pollen load and nectar sources.
Abstract: Pollen analyses of twelve honey samples collected in two successive years (2011-2012) from different towns and villages in Ekiti State, South western Nigeria were carried out in order to ascertain their pollen compositions. The results from the analysis revealed eighty-five taxa belong to thirty-three botanical families. Of these, thirty-two were i...
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Effects of Biochar Derived from Maize Stover and Rice Straw on the Early Growth of their Seedlings
Alie Kamara,
Mary Mankutu Mansaray,
Abibatu Kamara,
Patrick Andrew Sawyerr
Issue:
Volume 2, Issue 5, September 2014
Pages:
232-236
Received:
20 June 2014
Accepted:
8 July 2014
Published:
20 October 2014
Abstract: Crop residues such as maize and rice are important sources of nutrients and their restitution to the soil is an important residue management strategy for maintaining or improving soil and crop productivity. However, most maize and rice farmers in Sierra Leone burn crop residues during land preparation thereby depriving the soil of this vital resource. An alternative approach is the recycling of crop residues through biochar production. This study was therefore carried out to assess the effects of (i) maize stover biochar on the early growth of maize and (ii) rice straw biochar on the early growth of rice. In this study, biochar (0g, 12.5g, 25.0g, 37.5g and 50.0g) was mixed with 3kg of soil (fine sandy loam) and placed in perforated black polythene bags. Maize or rice seeds (3 per pot) were planted to 2cm depth and later thinned to one plant per pot. All pots were placed in the open under direct sunlight and rainfall. No supplemental irrigation was done since there was sufficient rainfall to supply the required moisture. The experiment was laid in completely randomized design with five treatments and three replications. After four weeks, the experiment was terminated. Mean plant height, stem girth, fresh- and dry-shoot weights of both maize and rice plants generally increased significantly (p<0.05) relative to the control at biochar applications ≥8.3g/kg soil. The results showed that growing maize and rice on soils treated with biochar derived from their residues (maize stover and rice straw respectively) has the potential to improve crop production. Confirmatory field trials and costs/benefits analysis of converting rice and maize residues to biochar will serve as a good guide for policy makers and end-users (farmers) for increased productivity of maize and rice in Sierra Leone.
Abstract: Crop residues such as maize and rice are important sources of nutrients and their restitution to the soil is an important residue management strategy for maintaining or improving soil and crop productivity. However, most maize and rice farmers in Sierra Leone burn crop residues during land preparation thereby depriving the soil of this vital resour...
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