Open Access Original Research Article

Influences of Some Preceding Winter Crops and Nitrogen Fertilizer Rates on Yield and Quality of Intercropped Maize with Cowpea

Sherif I. Abdel-Wahab, Wael M. El Sayed, Amal M. El Manzlawy

Journal of Experimental Agriculture International, Page 1-19
DOI: 10.9734/AJEA/2016/24385

A field study was conducted in Mallawi Agricultural Experiments and Research Station, Agricultural Research Center (ARC), El-Minia governorate, Egypt to decrease mineral nitrogen (N) inputs of maize with good yield quality and increase farmers' benefit. Local maize cultivar T.W.C. 310 was grown under intercropping and sole cultures in one row/ridge that received three mineral N fertilizer rates (75, 87.5 and 100% of the recommended N rate of maize), while local cultivar of cowpea seeds Keraim – 1 were drilled in one row and two rows/ridge under intercropping and sole cultures, respectively. A split split plot design with three replicates was used. Quality of maize grains was tested in the laboratories of Seed Technology Research Department, Field Crops Research Institute, ARC. Maize grain yield and its attributes were increased after harvest of legume crops compared to those grown after wheat harvest. Intercropping cowpea with maize increased grain yields per plant and per ha by 4.00 and 1.94%, respectively, in comparison with sole culture in addition to yielding 16.85 ton/ha of cowpea forage. Cowpea improved yield quality and N use efficiency (NUE) of intercropped maize after berseem cutting. Land equivalent ratio and land equivalent coefficient values for intercrops were much greater than 1.00 and 0.25, respectively, indicating less land requirements of intercropping system than sole maize. Farmer's benefit was achieved by intercropping cowpea with maize that received 87.5% of the recommended mineral N fertilizer rate of maize after berseem cutting.

Open Access Original Research Article

Molecular Characterization and Haemolysis of Bacteria Associated with Tilapia zilli from Ijaka-Oke Location on Yewa River

O. O. Oyelakin, A. A. Akinyemi, J. K. Ekelemu, A. R. Oloyede, B. O. Abiona

Journal of Experimental Agriculture International, Page 1-7
DOI: 10.9734/AJEA/2016/19984

Fishes are a source of animal protein, rich in minerals, amino acids, and essential fatty acids. Fishes can be confronted with microbial contamination in their natural habitat and their transformation products can be a source of microbial infections and food poisoning. In the natural habitat, microorganisms are usually found on the entire outer surface (skin and gills) and in the intestines of fishes. Genetic diversity study of the bacteria isolates was done using RAPD technique. Bacteria were isolated from the gills, gut and skin of Tilapia zilli from Ijaka-Oke location on Yewa River. Morphometric characteristics of the 20 Tilapia zillisampled was done. DNA were extracted from 20 bacteria isolates using CTAB method, PCR amplification of the 20 isolated DNA was carried out using five RAPD primers. Haemolysis of the 20 bacteria was also carried out using 7% of sheep blood in Nutrient Agar and it was used to culture a pure colony of the isolates and incubated at 37°C for 18 hours. The mean total length of the fishes was 30.00±9.00 (cm), weight 220±4.3 (g), head length 7.4±2.00 (cm) and standard length 21.30±4.50 (cm). The water quality parameters were also recorded with the water temperature at 22.90C, the pH of the water was 6.1 and Dissolved Oxygen 6.89 mg/l. Fifty – two (52) polymorphic markers were generated from the 5 RAPD markers. There were also 15 monomorphic markers from the primers. A total number of 67 markers were generated. The haemolysis showed that none of the bacteria displayed complete haemolysis.

Open Access Original Research Article

An Evaluation of Profit Margin of Sawyers of Wood Products in the Forestry Zone Surrounding Kumba (Cameroon)

Achille Jean Jaza Folefack, Marie Louise Avana Tientcheu, Géraldine Boudjiho Ngouegni, Joseph Florent Feulefack, Marc Parren

Journal of Experimental Agriculture International, Page 1-11
DOI: 10.9734/AJEA/2016/24991

A total of 235 chainsaw milling (CSM) operations have been visited from 1st June to 31st July 2011 in order to interview 85 sawyers from 15 villages in the forestry zone surrounding Kumba, Cameroon. In the field, four categories of sawyers (Type I, II, III, and IV) were differentiated according to their motivations, challenges, production cost and profit. The main motivation of sawyers is financial, regardless of their categories. The CSM average production amounts to 12.78 m3 per operation requiring 2 standing trees (approximately 6.22 m3 per tree) every two months. In total, with expenses of 34,719 FCFA/m3, sawyers get revenue of 40,999 FCFA/m3 (i.e. +5,780 FCFA/m3 as profit). However, Type II sawyers earn a much higher profit than others (+12,829 FCFA/m3). In general, CSM is an economically rewarding activity in that the majority of the sawyers visited earn significant profit exception made of Type III. Regretfully, forest control (licences’ check-up) is a major drawback that sawyers regularly face because of the illegality of their activity. Most sawyers operate in informal way without paying taxes/licences so that the loss of earning to the State revenues is important. The government should therefore legalize this activity by reforming the licences awarded to various sawyers and guiding the implementation of a more transparent and formal taxation in this sector.

Open Access Original Research Article

Comparation of Diets Used for Larviculture of Meagre (Argyrosomus regius Asso1801)

Nejdet Gültepe, Hakan Galip Dorlay, Mehmet İrşad Gültepe, Osman Sabri Kesbiç, Ümit Acar, Ferhat Yalgin

Journal of Experimental Agriculture International, Page 1-7
DOI: 10.9734/AJEA/2016/23259

This investigation compared the suitability of different diets for larviculture of meagre (Argyrosomus regius). For this purpose, wild fish were caught with longline and subsequently fed either a commercial diet or a mollusc diet. After two years, there was a significant difference between the two diets in the body weight but not the survival rate of the fish (P<0.05). Both the weight gain and the FCR were significantly higher in fish that were fed the commercial diet compared with those fed the mollusc diet. Three alga diets were used for the initial feeding of larvae: A1, A2 and A3, consisting of 30/70, 60/40 and 50/50 Nannochloropsis sp./Isochrysis sp., respectively. There was a significant difference in larval survival rate among the alga diets (P<0.05). These results indicate that meagre readily tolerates commercial production systems, where it can grow rapidly and easily reproduce.

Open Access Original Research Article

Yield and Quality of Intercropped Wheat with Faba Bean under Different Wheat Plant Densities and Slow – Release Nitrogen Fertilizer Rates in Sandy Soil

Tamer Ibrahim Abdel-Wahab, Amal Mahmoud Manzlawy

Journal of Experimental Agriculture International, Page 1-22
DOI: 10.9734/AJEA/2016/23895

The rapid increase of the population in Egypt together with a limited cultivated area results in an acute need for additional production of various crops. A two – year field trial was conducted in El-Boustan region, South El-Tahrir Province, El-Behira Governorate, Egypt to decrease mineral nitrogen (N) inputs of intercropped wheat and increase yield and quality of the intercrops for achieve farmer's benefit compared to sole wheat under sandy soil conditions. A split-plot design with three replications was used. Quality of wheat grains and faba bean seeds was tested in the laboratories of Seed Technology Research Department, Field Crops Research Institute, Agricultural Research Center. For faba bean crop, average yield of intercropped faba bean with wheat was greater by intercropping faba bean with four rows of wheat in the same ridge. Slow – release N fertilizer rates of wheat did not affect all the studied faba bean traits. Also, faba bean yield and its attributes were not affected by the interaction between wheat plant density and slow – release N fertilizer rates of wheat. Quality of faba bean seeds was not affected by wheat plant density, slow – release N fertilizer rates of wheat and the interaction between them. For wheat crop, intercropping faba bean with six rows of wheat in the same ridge had the highest grain and protein yields per ha compared to the others. All the studied wheat traits were increased by increasing N fertilizer rates of wheat from 190.4 to 285.6 kg N/ha except biological and straw yields per ha. The interaction between wheat plant density and slow – release N fertilizer rates of wheat affected significantly most of the studied wheat traits. Quality of wheat grains was not affected significantly by wheat plant density or by the interaction between wheat plant density and slow – release N fertilizer rates of wheat, meanwhile the reverse was true for slow – release N fertilizer rates of wheat. Intercropping faba bean with four rows of wheat that received 238.0 kg N/ha in form of urea slow – release N improved N uptake of wheat compared to the other treatments. Land equivalent ratio and land equivalent coefficient values for intercrops were much greater than 1.00 and 0.25, respectively, indicating less land requirements of intercropping systems than sole wheat. Farmer's benefit was achieved by intercropping faba bean with four rows of wheat that received 83.3% of the recommended mineral N fertilizer rate of wheat under sandy soil conditions.

Open Access Original Research Article

Synergistic Effects of Wood Ash and Essential Oil on Fecundity, Pupal Eclosion and Adult Mortality of Callosobruchus maculatus (Coleoptera: Bruchidae) Cowpea Seed Weevil

Akami Mazarin, Elias Nchiwan Nukenine, Changying Niu, Frederic Vencl Vincent

Journal of Experimental Agriculture International, Page 1-12
DOI: 10.9734/AJEA/2016/25306

Aims: The use of residual synthetic chemicals, although effective against stored product pests, has led to environmental degradation. However, the risk of target pests developing resistance to insecticides in addition to the high costs of synthetic insecticides has pushed researchers to find alternative control methods. Plant-based insecticides represent a suitable alternative control method because they are less toxic to non-target organisms and biodegradable. The present study investigates the potency of essential oil and wood ashes in the control of the stored product pest Callosobruchus maculatus (Coleoptera: Bruchidae).

Study Design: Bioassays were performed in glass jars. Insect rearing, oil extraction and wood ash preparation were done according to an established protocol. For each treatment, a randomized complete block design with four replications was used.

Place and Duration of Study: Laboratory of biology of the Faculty of Science, University of Ngaoundere, Cameroon from February 2013 to February 2014.

Methodology: Wood ash from two different plants and essential oil were used. We evaluated the single effects of our products before combining each wood ash at 0.4, 2, 10, 20 and 40 g/kg with the essential oil of Lippia adoensis at the rate of 0.05 mL/kg on different fitness parameters of C. maculatus. Data on insect mortality rate and adult emergence were assessed.

Results: In single applications, the susceptibility of C. maculatus was significantly (P = .05) higher to essential oil than wood ash with LC50 values of 2.64 mL/kg and 139.64 g/kg, respectively after the first day exposure. The essential oil was also more effective in reducing egg laying and adult emergence. However, the combination of wood ash and essential oil caused 98.69±1.32% mortality within six days of exposure, compared to 73.53±3.80% for wood ash and 77.44±2.91% for essential oil. The co-toxicity coefficients of the combination of the two substances for mortality (275.9), fecundity (562.61) and fertility (438.92) were higher than 120, suggesting a significant essential oil-ash synergistic interaction.

Conclusion: Essential oil was the most toxic in single applications for all treatments. But when applied in combination, a lowest dose of wood ash (0.8 mL/kg) instead of 40 g/kg was able to kill 98.69±1.32% of adults. Therefore, combining essential oil with wood ash could significantly (P = .05) improve on the efficacy of controlling C. maculatus in storage facilities. Knowledge gained from this study could be exploited by low income farmers as it could provide a cost effective strategy for crop storage without the use of enormous quantities of wood ash.

Open Access Original Research Article

Population Dynamics of the Mango Mealybug Rastrococcus invadens Williams (Homoptera: Pseudococcidea) in Western Burkina Faso

Karim Nébié, Souleymane Nacro, Lenli Claude Otoidobiga, Dona Dakouo, Irénée Somda

Journal of Experimental Agriculture International, Page 1-11
DOI: 10.9734/AJEA/2016/24819

Aims: The study aimed at determining the periods of high pest population of the mango tree mealybug Rastrococcus invadens Williams with respect to biotic and abiotic factors.

Study Design: Semiweekly observations were performed on the mango trees with a view of assessing the density of alive, dead or parasitized R. invadens.

Place and Duration of the Study: This study was conducted in Western Burkina Faso from May 2014 to April 2015.

Methodology: A set of mango trees was selected in each of the following locations: Toussiana, Bérégadougou and Orodara. The assessment was conducted on 20 leaves (five leaves per cardinal point) that were picked up from each mango tree at each observation date. The parasitized mealybugs were kept inside pill boxes for two weeks and the emerging parasitoids were collected and kept in alcohol 70°. Data were registered and processed with the Microsoft Excel 2010 and SPSS software.

Results: Results showed that R. invadens’ populations were more abundant during the wet season (May-September 2014) than the dry season (November 2014-April 2015) in all study locations. In general, parasitism was low. Some peaks of abundance were recorded in both wet and dry seasons. The evolution of the mortality of the insect pest was the same in all locations and peaks were observed from December 2014 to April 2015. The density of living R. invadens was significantly correlated with temperature and relative humidity. Impact of the parasitism due to Anagyrus mangicola Noyes and Gyranusoidea tebygi Noyes were also assessed and discussed.

Conclusion: Periods of R. invadens populations’ abundance are well known in Western Burkina Faso. The parasitoids A. mangicola and G. tebygi are well established. The level of parasitism could be improved by releasing of A. mangicola and G. tebygi to control R. invadens efficiently.