Open Access Original Research Article

Alterations Induced by Cowpea Weevil Callosobruhus maculatus F. (Coleoptera: Chrysomelidae) Infestation on Seed Germination Potential and Nutrient Quality of Vigna aconitifolia (Jacq.)

A. A. J. Mofunanya

International Journal of Plant & Soil Science, Page 1-10
DOI: 10.9734/IJPSS/2017/34265

Aims: To evaluate alterations induced by cowpea weevil Callosobruhus maculatus (C. maculatus) infestation on seed germination potential and nutrient quality of Vigna aconitifolia (V. aconitifolia).

Experimental Design: The research was carried out in a complete randomized block design.

Place and Duration of Study: Department of Botany, University of Calabar, Calabar, Nigeria, between March and June, 2016.

Methodology: A mix of V. aconitifolia seeds was bought, infested seeds sorted from the non infested ones at different levels of infestation and kept for three months before planting to ascertain alteration induced by C. maculatus on seed germination potential. The other seeds were sundried, milled into powder and used for proximate, minerals and vitamins analysis.

Results: Significant (P = .05) alterations induced by C. maculatus on seeds germination ability and nutrient quality of V. aconitifolia were observed. These changes varied according to the severity of infestation. The germination potential of seeds was affected with significant reductions observed at all levels of infestation with respect to soil types compared to seeds before infestation (BI). Seed germination was the highest in sandy and loamy than in clay soil. Percentage germination observed on the eleventh day for seeds planted on clay, sandy and loamy soil were 61.7%, 87.1% and 66.7% (BI) compared to values of 4.2%, 6.1% and 5.3% respectively at severe infestation (SI). Results revealed that after infestation (AI) seeds of V. aconitifolia had significant (P = .05) decrease at SI level of 10.1% for moisture, 44.2% (ash), 25.5 % (fat), 18.0% (fibre) and 12.4% (carbohydrate) while protein had increase of  40.2%. P, Na, Cu and Ni showed decrease in content while K, Ca, Mg, Fe, Zn, Mn, Co depicted increase at all levels of infestation compared to seeds content BI. Lead was not detected. Significant decrease in vitamins A, BI, B2, B3, B5, B6, B9, C and biotin contents of the cowpea with decrease in severity of infestation was found. Vitamin E revealed increase with increase in severity of infestation.

Conclusion: Callosobruchus maculatus infestation damaged seeds resulting in a reduction in the germination ability and marketability of V. aconitifolia seeds with severe alteration in nutritional quality.

Open Access Original Research Article

Salt Stress Elevates Endogenous Phytohormones and Activates Antioxidative Defense System in Leaves of Spinacia oleracea (Spinach)

C. O. Olaiya, K. O. Karigidi, E. E. Idanegbe, O. S. Fagbami

International Journal of Plant & Soil Science, Page 1-7
DOI: 10.9734/IJPSS/2017/27823

Aims: Salinity stress is one of the major environmental stresses and continues to limit the growth and productivity of most food crops. Therefore, the aim of this research was to evaluate the effects of salinity stress on endogenous phytohormones and antioxidative defense system of Spinacia oleracea.

Study Design: Salinity stress was induced using three concentrations (50 mM, 100 mM and 150mM) of sodium chloride (NaCl). The treatments were laid out in complete randomized blocks with three replicates each.

Place and Duration of Study: The experiment was conducted in the screen house of the Department of Biochemistry, University of Ibadan, Nigeria for eight weeks.

Methodology: After eight weeks of planting on saline soil, fresh leaves were harvested and biochemical analysis was carried out on the leaves to determine the effect of salinity stress on photosynthetic pigments, minerals, antioxidative enzymes, indole-acetic acid (IAA) and gibberellic acid (GA) using standard methods. Data were statistically analyzed by one way ANOVA and Duncan's multiple range tests were performed to test the differences among treatments at P<0.05.

Results: Results showed that treatment with 150 mM NaCl increased the level of IAA, GA,  catalase (CAT), superoxide dismutase (SOD)  and sodium significantly (P<0.05) in Spinacia oleracea leaves, while photosynthetic pigments, glutathione peroxidase, magnesium, manganese, potassium and iron were significantly decreased (P<0.05).

Conclusion: These results suggest that Spinacia oleracea responds to salinity stress via an elevation of CAT, SOD, IAA and GA.

Open Access Original Research Article

In vitro Evaluation of Fungicides and Biocontrol Agents against Rhizoctonia solani in Tomato

M. Rajendraprasad, B. Vidyasagar, G. Uma Devi, S. R. Koteswar Rao

International Journal of Plant & Soil Science, Page 1-9
DOI: 10.9734/IJPSS/2017/35307

Twenty four fungal biocontrol agents and twelve bacterial biocontrol agents were screened for their efficacy against phytopathogenic fungi Rhizoctonia solani through dual culture technique. Trichoderma harzianum-1 and Pseudomonas fluorescence-2 were found effective in inhibition of mycelium (62.53, 62.20) of Rhizoctonia solani under in vitro conditions. Ten fungicides were tested for their efficacy against Rhizoctonia solani through poisoned food technique and the ten fungicides Tebuconazole + Trifloxystrobin, Propiconazole, Captan + Hexaconazole and Carbendazim were record 100 per cent at recommended and half the recommended dosage under in vitro condition.

Open Access Original Research Article

Effect of Mulch Types and Mineral Fertilizer Rates on Cabbage (Brassica Oleracea var. Capitata) Growth and Yield in the Highlands of Rwanda

Chantal Uwituze, Hamudu Rukangantambara, Joyce J. Lelei

International Journal of Plant & Soil Science, Page 1-15
DOI: 10.9734/IJPSS/2017/34685

Aim: Determine response of cabbage growth and yield to mulching and fertilizer application.

Study Design: Factorial arrangement (3 × 4) of mulching types (black plastic, wheat straw and bare soil) and four NPK fertilizer rates; 0, 60, 120 and 180 kg ha-1, in a RCBD with three replicates.

Place and Duration of Study: Busogo sector Musanze District, Rwanda, from September 2016 to March 2017.

Methodology: Data on cabbage stem diameter, height, leaf area index (LAI), head diameter and weight was collected and subjected to ANOVA using SAS version 9.3. Mean separation was done using LSD at P = .05.

Results: Application of black plastic and wheat straw mulch significantly increased cabbage stem diameter, height, leaf area index (LAI), head diameter and weight compared to bare soil. Fertilizer rates of 60 and 120 kgha-1 significantly increased cabbage growth and yields.

Conclusion: Application of wheat straw mulch is recommended in increasing cabbage growth and yields. It is cheaper than plastic mulch and contributes to soil organic matter increase. NPK fertilizer rate of 120 kg ha-1 is recommended to meet the nutrient demand of cabbage and increase yield.

Open Access Original Research Article

Variability of Leaf Characteristics in Seedlings of Pubescent Oak of Kırıkkale, Turkey

Cengiz Yücedağ, Halil Barış Özel

International Journal of Plant & Soil Science, Page 1-7
DOI: 10.9734/IJPSS/2017/34956

In the present study, the variability of leaf characteristics in seedlings of six populations of pubescent oak was studied at Kırıkkale, Turkey. For this purpose, 3 years old pubescent oak (Quercus pubescens Willd) seedlings were used and about 30 leaves of completely developed and matured were taken from each population for collecting data. Data were analyzed by using univariate, Pearson’s correlation coefficient and Hierarchical cluster analysis. A high variability was revealed by petiole length, total leaf length and width. There is no differentiation among populations in terms of number of intercalary veins and number of lobes. Groups of Duncan test conformed to those of hierarchical cluster analysis. For example, the northern populations were in another group while the southern populations replaced in one homogeny group. Future studies on all Turkish populations of Pubescent oak will help to find centers of genetic diversity and populations with specific adaptations to drought and frost.