Open Access Original Research Article

Evaluation of Calcium Regulating Role of Calcium Oxalate Crystals in Eddo Corms in Hydroponic Solution Containing Calcium at Different Concentrations

Mohammad Nazrul Islam, Shilpi Islam, Michio Kawasaki

Asian Research Journal of Agriculture, Page 1-12
DOI: 10.9734/ARJA/2018/45106

Aims: Involvement of calcium oxalate crystals in the maintenance of calcium homeostasis in the corms of eddo in hydroponic solution containing calcium at different concentrations was investigated.

Study Design: Plants of eddo [Colocasia esculenta (L.) Schott var. antiquorum Hubbard & Rehder] cv. Aichiwase was used in this study. Seed corms were planted in plastic pots filled with vermiculite and the plants were sprouted by watering under natural temperature, light and humidity conditions in the green house at Hirosaki University, Hirosaki, Japan. After 2 months the plants were grown in a growth chamber. Plants with new growing corms were subjected to grown in water culture solutions containing one of the four treatments as 0 mM calcium, 1 mM calcium nitrate (control), 15 mM calcium nitrate and 15 mM calcium chloride.

Results and Discussion: Under scanning electron microscopy and optical microscopy, few number of raphide crystals were observed in the cortex and many druse crystals were observed in the lateral part containing cortex, the connecting part between root and corm, and the peripheral part of stele. Very few number of druse crystals were observed in the center part of stele. The number and size of crystals in the lateral part of corms under 1 mM calcium nitrate treatment were significantly higher than that in 0 mM calcium solution and were significantly lower than that in the 15 mM calcium solutions. Calcium mapping images by energy dispersive X-ray spectrometry showed a positive correlation between the amounts of calcium in the lateral part of corms and calcium concentration in treatment solutions. The weight percentage of calcium relative to the total weight of major constituent elements per crystal idioblast was significantly higher than that per parenchyma cell in the lateral part. However, the weight percentage of calcium per parenchyma cell except idioblasts of the lateral part was stable among the treatments. The results suggest that calcium is accumulated in crystals under calcium-excessive conditions and is released from crystals under calcium-deficient conditions for stabilisation of calcium levels in the tissues other than the idioblasts in the lateral part of eddo corm. In addition, the weight percentage of calcium per storage parenchyma cell of stele was stable among the treatments and was significantly lower than the weight percentage of calcium per parenchyma cell of the lateral part.

Conclusion: The results indicate that calcium delivered from roots is mostly entered at the lateral parts of corms and is accumulated in calcium oxalate crystals in the cortex, the connecting part between root and corm, and the peripheral part of stele. As a result, calcium contents of the storage parenchyma cells of stele may remain stable at a low level under different calcium treatments.

Open Access Original Research Article

Physicochemical Properties and Bacteriological Profile of Wheat Flours Produced and (or) Sold in Calabar, Nigeria

Jeffrey A. Nosa-Obamwonyi, Sylvester P. Antai

Asian Research Journal of Agriculture, Page 1-11
DOI: 10.9734/ARJA/2018/45491

This study was aimed at investigating the physicochemical properties and bacteriological profile of white wheaten flour, wheat semolina and whole wheat meal produced and/or sold in Calabar. Ten (10) samples of each flour type was bought from ten strategic locations and analysed. The following physicochemical parameters of the samples were analysed: pH, moisture, ash, fat, gluten, protein, falling number. Microbiologically, total mesophilic aerobic bacteria (TMAB), total coliform count (TCC), Escherichia coli, Salmonella spp, Bacillus cereus and Clostridium perfringens counts were determined. Results showed that the ash contents of five white wheaten flour samples and the fat content of one white wheaten sample did not conform to SON (Standards Organisation of Nigeria) standards. TMAB and TCC of all samples conformed to SON standards. Salmonella spp was identified in 10% of all samples and E. coli was identified in one wheat semolina sample. However, Bacillus cereus and Clostridium perfringens were not detected in any of the samples. One-way analysis of variance (ANOVA) showed that there were significant differences (< 0.01) between the three wheat flour types for ash, fat, gluten and protein, falling number, TMAB and TCC. This study highlights the need for product monitoring by relevant regulatory agencies to ensure conformity to standards.

Open Access Original Research Article

Evaluation of Cowpea Genotypes for Drought Tolerance Using the Pot Screening Approach

M. S. Alidu

Asian Research Journal of Agriculture, Page 1-11
DOI: 10.9734/ARJA/2018/45806

Background: Tolerance to drought is crucial for cowpea producers in Northern Ghana, where the bulk of the crop is produced

Aims: To assess Five cowpea genotypes for their tolerance to drought at various stages of development.

Study Design: Randomized complete block design was used for the study.

Place and Duration of Study: The study was carried out in pots over a three-month period at the Savanna Agricultural Research Institute, Tamale-Northern Ghana.

Methodology: The study made use of factorial experiment in randomized complete block design using two factors (genotypes and water stress regimes). Treatment combinations were replicated three times. Genotypes were subjected to moisture stress at either the vegetative, flowering or pod filling stages. A well-watered control was included.

Results: Though the analysis of variance indicated significant main effects for genotype and moisture stress for a number of traits studied, no significant interactions between the two factors were evident for the traits studied. Moisture stress significantly reduced the number of pods per plant and grain yield. Moisture stress imposed during the vegetative phase has the most significant reduction in grain yield and number of pods per plant compared to the irrigated control. In general, the correlation coefficients were weak and not statistically significant. All the significant correlation coefficients were positive and were found between grain yield and its components. Also, the relationship between susceptibility to moisture stress and yield potential was investigated by correlation and regression analysis. This study indicated a significant positive relationship between susceptibility to moisture stress and yield potential.

Conclusions: No single genotype was found to be most tolerant to drought for all the three growth stages in which drought was imposed. The study, therefore, emphasised the difficulty in combining high yield potential and drought tolerance in development cowpea genotypes.

Open Access Original Research Article

Enhancing Soil Fertility, Maize Grain Yield and Nutrients Composition through Different Planting Time and Manure Sources in Farmers’ Fields of Southeastern Nigeria

J. C. Nwite, S. O. Nwafor, A. O. Nwangwu, O. C. Olejeme

Asian Research Journal of Agriculture, Page 1-12
DOI: 10.9734/ARJA/2018/43572

Maize (Zea mays L.) has a good potential as a cereal crop side by side with rice and wheat. Irrespective of its local and industrial uses, the production is still challenged by some factors as environmental changes associated with different sowing date and a decline in soil fertility. A field experiment was conducted at the research farm of the Federal College of Agriculture, Ishiagu, Ebonyi State, during the 2015/2016 cropping season. The study used a split-plot in a randomised complete block design which aimed at evaluating the effect of different time of planting and manure sources on selected soil chemical properties, maize grain yield and its proximate nutritive values for enhanced food security. The soil amendments used and their combinations are poultry droppings (PD), NPK 15:15:15 fertiliser, rice husk dust (RHD), poultry droppings + rice husk dust, NPK + rice husk dust, poultry dropping + NPK + rice husk dust and control. The soil parameters studied include soil pH, organic carbon, total nitrogen and cation exchange capacity. The maize grain yield was determined at harvest and the grain nutrients analysed include moisture content, crude fat, crude protein and ash content percentages. Results showed significant differences among the two planting times and soil amendments in all the soil parameters studied including their interactions. Maize planted in April increased the fresh cobs weight (18.37%) higher than those planted in May (11.19%) as PD amended plots increased the fresh cobs weight (2.71 t/ha) significantly (P < 0.05) higher. Maize grain ash percent (1.431%) was improved higher in May than April (1.403%). However, the percentage of moisture contents (MC) and crude fat (CF) (10.46% and 4.237%), respectively, of the maize grain were significantly higher in PD amended plots. Integration of NPK + PD + RHD gave the highest (1.52%) significant (P < 0.05) ash percent in the two planting periods. Plots treated with NPK+PD+RHD in May improved the crude protein higher than other treatments. Proper dissemination of this integrated nutrient management approach to the rural farmers could promote sustainable management practices among smallholder farmers, and ultimately sustain and boost maize production.

Open Access Original Research Article

Developmental Stages of African Sweetpotato Weevil Cylas puncticollis Boheman (Coleoptera: Brentidae) in Sudan

Amin ELzubeir, EL-Imam EL-Khidir, Kamal Mowafi

Asian Research Journal of Agriculture, Page 1-6
DOI: 10.9734/ARJA/2018/45767

The biology of the developmental stages of the weevil, Cylas puncticollis Boheman a pest of sweet potato roots was carried out under laboratory conditions at ambient room condition and relative humidity (RH) and at a constant temperature of 30°C and 65% RH. Average pre-oviposition period under ambient room conditions was 4.33 ± 1.23 days. The incubation period lasted 2-4 and 3 days under room conditions and the constant temperature and RH, respectively. The larval period lasted 9.63-12.00 and 12.56-14.57 days under room conditions and the constant temperature and RH, respectively. The pupal period ranged from 3.0 to 3.29 days under room conditions and from 3.4 to 4.0 days under the constant temperature and RH. The sex ratio was 1:0.9. The pre-oviposition rate was 3.90 ± 1.67 eggs per female per day under room ambient conditions and under a constant temperature of 30°C and 65% RH a highly significant difference was recorded on the total developmental stages duration; also a significant difference was registered between rearing under room ambient conditions and the constant temperature and RH conditions.