Open Access Original Research Article

Investigation of the Salt Tolerance of Wheat Genotypes: Changes in Antioxidants, Total Protein, K+/Na+ Ions and Grain Yield

Shabnam Kamyab, Bahram Heidari

Biotechnology Journal International, Page 1-10
DOI: 10.9734/BBJ/2016/26656

Salt stress causes huge losses of agricultural productivity worldwide, negatively affects soil properties and limits plants growth. In the present study, response of 11 wheat (Triticum aestivum) landrace varieties, 2 commercial cultivars and 2 promising lines to three levels of salinity (EC= 7, 14 and 21 dS m-1) was assessed based on variations in grain yield, antioxidants, and Na+ and K+ ions. Pots were daily weighed and irrigation with saline solution (1:1 ratio of NaCl and CaCl2 salts) was performed based on field capacity (FC) 50 days after sowing at the four-leaf stage of growth. Results of linear regression showed that K+/Na+ ratio had strong direct relation (R2=0.98) in root and leaf. Correlation between grain yield in control and salinized conditions was supported by positive regression coefficient (b=0.853) in regression equation (R2=0.65). This correlation showed that superior genotypes in control condition produced higher grain yield under salinized conditions. Enzymatic antioxidants (superoxide dismutase, SOD and peroxides, POD) and total protein content were increased as the level of salinity increased from EC= 7 to EC=21 dS m-1. K+/Na+ ratio in the leaf and grain yield were reduced as the level of salinity increased. Overall, results showed that great variations was existed between genotypes for three types of traits and selections can be made using a weighted index defined based on changes in antioxidants, protein, ions and grain yield.

Open Access Original Research Article

Dietary Effect of Different Drying Methods and Graded Inclusion Levels of Ginger (Zingiber officinale) on the Performance and Gut Morphology of Broilers

G. O. Adeyemo, E. O. Ogunshote, O. G. Longe

Biotechnology Journal International, Page 1-9
DOI: 10.9734/BBJ/2016/24716

The effect of processing methods and varying dietary inclusion levels of ginger on performance and gut morphology of broilers was studied. Ten experimental diets designated as diet 1 (control 0% ginger inclusion), diet 2 (sundried ginger at 1%), diet 3 (sundried ginger at 1.5%), diet 4 (sundried ginger at 2%), diet 5 (air-dried ginger at 1%), diet 6 (air-dried ginger at 1.5%), diet 7 (air-dried ginger at 2%), diet 8 (oven-dried ginger at 1%), diet 9 (oven-dried ginger at 1.5%) and diet 10 (oven-dried ginger at 2%) were fed to the broilers ad-libitum. The experimental design was a 3 by 3 factorial arrangement in a completely randomized design. Three hundred broilers were used for the experiment; they were randomly allotted to the ten dietary treatments with 5 replicates per treatment and 6 birds per replicate. The birds were weighed weekly to determine their weight gain, body weight and feed conversion ratio. Thirty finisher birds were sacrificed and the ileum and duodenum removed for gut histo-morphometry.

Results showed that drying methods influenced performance. This was observed for the average body weight gained per bird per day while the effect of the inclusion level was observed on the feed conversion ratio. Factor interaction was observed for weight gained/bird per day and feed conversion ratio. However, only numerical differences were observed for average final body weight/bird and average feed intake /bird/day.

Duodenal and ilea, villous height showed significant effect (P<0.05) of drying method, inclusion levels and treatment interaction with the control having the highest mean values. 

It can be concluded that supplementing broiler feed with air-dried ginger at 1.5% inclusion level can be effective as it led to an increase in the final body weight, average body weight gained per day per bird and average feed intake. No effect of drying methods and inclusion levels were observed for the histo-morphometry.

Open Access Original Research Article

Metagenomic Analysis of Microbial Communities in the Soil-mousse Surrounding of an Amazonian Geothermal Spring in Peru

Sujay Paul, Yolanda Cortez, Nadia Vera, Gretty K. Villena, Marcel Gutiérrez-Correa

Biotechnology Journal International, Page 1-11
DOI: 10.9734/BBJ/2016/27519

Aim: Aguas Calientes (AC) is one of the very few geothermal springs located deep into the Amazon rainforest in Peru. The main aim of this study was to generate an illumina based high resolution microbial phylogenetic profile of the soil-mousse surrounding of an Amazonian geothermal spring like AC.

Study Design: Soil-mousse surrounding of AC geothermal spring was subjected to metagenome sequencing using Illumina HiSeq platform.

Place and Duration of Study: Soil samples were collected from the surrounding of Aguas Calientes (7°21'12'' S, 75°00'54'' W). The duration of the study was from 2013-2016.

Methodology: Metagenomic DNA was extracted from pooled soil samples using PowerSoil® DNA isolation kit and analyzed at 16S rRNA V3-V4 hypervariable region by amplicon metagenome sequencing on Illumina Hiseq platform. QIIME pipeline was used for 16S RNA detection, clustering and Operational Taxonomic Units (OTUs) picking followed by Biom file generation and statistical analysis. Functional analysis of 16S amplicons was performed using the default settings of PICRUSt.

Results: A total of 72 bacterial phyla and 3 archaeal phyla were detected in AC soil. Proteobacteria (50.09%) was found to be the highest represented phylum among bacterial communities while among archaeal communities Crenarchaeota (0.26%) dominated the sample. More than 50% of the sequences in AC soil were found unidentified/novel at the genus level. A plausible facultative mutualistic relationship was predicted among some members of the communities. In Clusters of Orthologs (COGs) analysis, most of the sequences were found to be associated with “Amino acid transport and metabolism” (8.3%) category, while among predicted Kyoto Encyclopedia of Genes and Genomes (KEGGs) pathways "Membrane transport" (12.1%) was the most abundant one.

Conclusion: This is the first report of a high resolution microbial phylogenetic profile of an Amazonian geothermal spring soil-mousse surrounding. Although a very diverse group of the bacterial and archaeal population was observed in the sample, a large portion of unidentified thermophilic microbial members was also noticed which need to be studied.

Open Access Original Research Article

Screen House and Field Resistance of Taro Cultivars to Taro Leaf Blight Disease (Phytophtora colocasiae)

Fokunang Charles, Mbong Grace, Manju Evelyn, Tembe Estella, Rachid Hanna

Biotechnology Journal International, Page 1-15
DOI: 10.9734/BBJ/2016/14317

Introduction: Taro leaf blight disease cause by Phytophtora colocasiae has become an economic disease in Cocoyam growing regions of Cameroon.

Aims: To screen for resistance 10 improved and 4 local cultivars of taro against taro leaf blight disease.

Study Design: A randomized complete block design study.

Place of Study: Studies were conducted at the International Institute of Tropical Agriculture (IITA) Yaounde Nkolbisson from July 2013 to January 2014.

Methodology: Taro cultivars from tissue culture were planted in the screen house conditions and tested for virulence and pathogenicity with 4 isolates of Phythophthora colocasiae at spore density of 3×104 spores /ml of distilled water. Plants were planted in the field to assess disease incidence and severity.

Results: The results obtained on the different taro cultivars, revealed that all the 4 isolates showed variable pathogenicity. They caused lesions on inoculated leaves. There was variability in pathogenicity based on the small lesion lengths produced on cultivars, these included BL/SM132 and Red petiole. Isolate 3 showed a stronger sensitivity to leaf collapse and defoliation irrespective of the cultivar tested. There was a significant difference (p = 0.05) in tissue collapse and leaf defoliation on exposure to the different fungal isolates. The result of field infection rates of P. colocasiae at 126 DAP-154 DAP on 10 improved and 4 local cultivars indicated that there was significant variability (p = 0.05) in incidence and disease severity, with high incidence and severity occurring at 154 DAP in all cultivars. Improved cultivar BL/SM132 showed no classic symptoms of P. colocasiae and therefore it was resistant to Phytophthora colocasiae.

Conclusion: The results obtained on virulence and pathogenicity of Phythophthora colocasiae on the different taro cultivars revealed that all the 4 isolates showed variable pathogenicity. They caused lesions, on inoculated leaves. Isolate 3 showed a stronger sensitivity to leaf collapse and defoliation irrespective of the cultivar tested. The result of field infection rates of P. colocasiae at 126 DAP-154 DAP on 10 improved and 4 local cultivars indicated that there was a significant variability (p = 0.05) in disease incidence and severity, with high incidence and severity occurring at 154 DAP in all cultivars. Improved cultivar BL/SM132 showed no classic symptoms of P. colocasiae and therefore it was resistant to Phytophthora colocasiae as compared to all the other cultivars which showed high severity rates of infection of the disease and thus were susceptible to the disease.

Open Access Original Research Article

Sodium Alginate/Polyvinyl Alcohol Immobilization of Brevibacillus brevis OZF6 Isolated from Waste Water and Its Role in the Removal of Toxic Chromate

Parvaze Ahmad Wani, Akinware Najimdeen Olamide, Nusrat Rafi, Shazia Wahid, Idris Adegbite Wasiu, Oduleye Olatunji Sunday

Biotechnology Journal International, Page 1-10
DOI: 10.9734/BBJ/2016/27341

Aim: In this study we wanted to determine bacteria for chromium (VI) removal under pH, chromium concentration, carbon source and immobilizing agents.

Place and Duration of Study: This study was carried out in the Department of Biological Sciences, College of Natural and Applied Sciences, Crescent University, Abeokuta, Nigeria in the year 2015.

Methodology: Isolation of bacteria was done from industrial waste water of Abeokuta, Nigeria which is often released into water bodies and thus contaminates water during 2015. Nutrient agar added with 100 µg/ml Cr (VI) was used to isolate resistant bacterial strains. Resistance of the strains for Cr (VI) was evaluated on nutrient agar media. Natural material [sodium aliginate (SA)] and synthetic material (PVA)] immobilized bacterial cells for Cr (VI) removal experiment was done by 1, 5–diphenyl carbazide method.

Results: The strain OZF6 was characterized as Brevibacillus brevis using 16S rRNA gene sequence. All isolates (8 strains) were tolerant to chromium (VI). Among all strains, only Brevibacillus brevis OFZ6 reduced Chromium (VI). Brevibacillus brevis OZF6 reduced maximum Cr (VI) (72.5%) at pH 7. Brevibacillus brevis OFZ6 also reduced chromium (VI) significantly under various concentrations of chromium. Brevibacillus brevis OZF6 detoxified the metal 81% at 50 μg Cr/ ml, 75% at a concentration of 100 μg/ ml and 68% at 150 μg/ ml respectively. Among electron donors, maximum reduction was observed under influence of lactose. Among different matrices combinations for whole cell immobilization of OZF6, combination of 10% PVA, 10% sodium alginate (SA) proved to be best combination for Cr (VI) reduction.

Conclusion: Due to above properties, bacteria will be utilized for Cr (VI) detoxification in contaminated industrial waste water and thus will protect environment from contamination. There needs a proper regulation and treatment of these effluents prior their release into water bodies or into soil and thus ultimately protect population from carcinogenesis and other ill hazards.