Open Access Original Research Article - (Regular Section)

Performance of Improved Sweet Potato (Ipomea batatas L.) Varieties in Makurdi, Southern Guinea Savanna of Nigeria

O. M. Egbe, S. O. Afuape, J. A. Idoko

Journal of Experimental Agriculture International, Page 573-586
DOI: 10.9734/AJEA/2012/1347

Aim: To investigate the performance of some improved sweet potato varieties obtained from the National Root Crops Research Institute (NRCRI), Umudike, Nigeria, for root yield and other yield components. 
Study Design: Field experiment.
Place and Duration of Study: Teaching and Research Farm of the Federal University of Agriculture, Makurdi in Benue State, located in the Southern Guinea Savanna of Nigeria from June-November of 2010 and 2011. 
Materials and Methods: The treatments comprised of eleven sweet potato varieties [CIP 440141, K134, NASPOT4, NASPOT2, SPK004, TIS87/0087(check), CIP440037, 1900411, NARSP/05/007C, CIP440293 (orange skin and flesh) and NARSP/05/022 (orange flesh)] set out in randomized complete block design with three replications. Ten farmers were used for the preference test of the varieties.
Results: Some vegetative growth parameters evaluated in the study (number of branches/plant, internodes length, number of leaves per plant and vine length) increased at different rates between 4 - 16 weeks after planting. Root diameter and length, number of saleable roots and weight varied with the varieties of sweet potato in Makurdi. NARSP/05/022 gave the highest number of leaves, number of roots (121817/ha) and weight (54151 kg/ha) at harvest, although it also had the highest incidence of sweet potato weevil infestation. This variety was the only one that had significantly higher saleable root weight than the check (TIS 87/0087). Saleable root weight correlated positively and significantly with number of saleable roots and root diameter. 
Conclusion: Farmers will likely consider NARSP/05/022 for adoption despite the high weevil infestation. For reasons other than root yield (taste and colour), farmers may adopt CIP440293.

Open Access Others

Corrigendum: Diallel Cross Analysis in Sugar Beet (Beta vulgaris L.): Identification of the Best Parents and Hybrids for Resistance to Bolting and Cercospora Leaf Spot in Sugar Beet Monogerm O-type Lines

Mohsen Niazian, Reza Amiri, Abazar Rajabi, Mohammad Reza Orazizadeh

Journal of Experimental Agriculture International, Page 700-711
DOI: 10.9734/AJEA/2012/485

Corrigendum for 

It has been drawn to the journal's attention (by the corresponding author) that there is error in the author list of the published paper. Therefore, following the and  this Corrigendum is processed. We have great respect and we generally follow the guidelines, given by COMMITTEE ON PUBLICATION ETHICS  for any publication disputes, authorship disputes, etc. In this regard, we are thankful for the patience and help of all concerned people, as ‘authorship dispute resolution’ is a long process.

Open Access Original Research Article

Resistance of Eggplant (Solanum melongena L.) to Verticillium Wilt Correlates to Microbial Abundance and Soil Enzyme Activities

B. L. Zhou, Z. X. Chen, L. Du, X. L. Ye, Y. F. Liu

Journal of Experimental Agriculture International, Page 557-572
DOI: 10.9734/AJEA/2012/1380

Aims: To determine the relationship between microbial abundance and enzyme activities of rhizosphere soil from different resistant eggplant cultivars and resistance of eggplant to Verticillium wilt.
Study Design: The changes of microbial and enzymatic activities of the rhizosphere soil from different resistant eggplants after inoculation of Verticillium dahliae were analysed.
Place and Duration of Study: The plants were grown in a plastic greenhouse of the Vegetable Crops Experimental Station, and the laboratory experiments were conducted at the Horticulture College, Shenyang Agricultural University from August to November, 2008.
Methodology: 14 eggplant cultivars were selected and inoculated with Verticillium dahliae to screen their resistance against Verticillium wilt, and classified according the final disease index. The quantities of main cultivable microorganisms and some functional bacteria were investigated by the serial dilution method. Activities of oxidoreductase and hydrolase enzymes of rhizosphere soil were determined by spectrophotometry or colorimetric titrations.
Results: The correlation analysis among resistance of eggplant to Verticillium wilt, microorganisms and enzyme activities showed that, the abundance of actinomyces, the ratios of bacteria to fungi and actinomyces to fungi, and the activities of catalase, polyphenol oxidase, protease and urease, were significantly positively related with the resistance.

Open Access Original Research Article

Prevalence of Coat Colour Phenotypes in West African Dwarf Sheep Reared by Small Holder Farmers in South Western Nigeria

M. N. Bemji, A. A. Ogunjimi, A. J. Ode, S. R. Okediji, A. T. Akinwunmi, T. O. Sanyaolu, B. S. Salawudeen, B. A. Kelani, A. O. Ogunsola, M. O. Agunbiade, A. S. Adenaike, A. I. Ogundiyi

Journal of Experimental Agriculture International, Page 587-596
DOI: 10.9734/AJEA/2012/1544

The West African Dwarf (WAD) sheep reared extensively by small holder farmers in South Western Nigeria has not been selected based on preference for coat colour, which varies considerably but without adequate information on the current distribution. The prevalence of different coat colour phenotypes was therefore investigated based on a total randomly sampled size of 9, 195 sheep (5,978 females and 3,217 males) from February to October, 2011. A total of 17 different colour patterns including 3 solid colours (white, black and brown) were identified in the breed. Phenotypes mainly influenced by phaeomelanin pigment, considered to be governed by a dominant allele (Awt) include: predominantly white with black marking, solid white, white and black in approximately equal proportions, spotted white, white and brown in approximately equal proportions, buckskin, tan, badgerface and grey. The remaining phenotypes (black with white marking, brown, black, spotted black, spotted brown, black and brown, brown with white marking and Swiss marking) reflected the presence of eumelanin pigment governed by Aa recessive allele. Based on the two pigment types, 71.58% and 28.42% of sheep had coat colour predominated by phaeomelanin and eumelanin pigments, respectively. Result of chi square (X2) analysis showed that the difference between observed and expected frequencies was significant (P=.05) implying that there was a deviation from the expected 3:1 Mendelian ratio. Conscious selection could be embarked upon to investigate and conserve phenotypes that are more genetically superior in terms of productivity and adaptation.

Open Access Original Research Article

Application of SSR Markers for Genetic Purity Analysis of Parental Inbred Lines and Some Commercial Hybrid Maize (Zea mays L.)

I. O. Daniel, J. A. Adetumbi, O. O. Oyelakin, S. A. Olakojo, M. O. Ajala, S. O. Onagbesan

Journal of Experimental Agriculture International, Page 597-606
DOI: 10.9734/AJEA/2012/1579

Aims: Morphological evaluation of seeds and growing plants used for certification for purity and variety distinctness in Nigeria is time consuming and expensive. This experiment set to evaluate the usefulness of SSR markers to determine genetic purity of commercial hybrids and their inbred lines. 
Place and Duration of Study: Bioscience unit, International Institute of Tropical Agriculture, Nigeria in December, 2011
Methodology: Seedlings of four F1 hybrids and four inbred lines were grown in the screen house of IITA for DNA extraction using Dellaporta method with some modifications. Six Simple Sequence Repeat (SSR) markers were used for Polymerase Chain Reaction (PCR) using Touch-Down PCR profile. The analysis is by fragment analysis as present (1) or absent (0) Mathematical equation to determine genetic purity of the genotypes was developed from the genetic distances matrix.
Results: Simple descriptive analysis revealed that average genetic diversity and polymorphism information content (PIC) recorded by the markers was 0.592 and 0.512 respectively. Genetic purity level of inbred lines ranged between 91.3% and 98.7% while the hybrids ranged between 81.3% and 95%.
Conclusion: SSR markers are powerful biotechnological tool capable of detecting genetic purity status of Nigerian maize hybrids therefore inclusion of DNA analysis of seeds using SSR markers to determine genetic purity of maize seed is recommended. However, further research work with larger number of seed samples per variety will be needed to validate reliability.

Open Access Original Research Article

Evaluation of the Efficacy of Different Rates of Herbicides on Weed Growth and Grain Yield of Two Rice Varieties in Two Rice Ecologies in Sierra Leone

S. S. Harding, D. R. Taylor, A. B. Jalloh, N. Mahmood, C. A. Dixon, S. D. Johnson

Journal of Experimental Agriculture International, Page 607-615
DOI: 10.9734/AJEA/2012/1611

Two rice varieties, NERICA L19 (weed competitive) and ROK10 (high yielding) were subjected to two pre-emergence (RiceForce and ButaForce) and two post-emergence (Stam and RiceForce) with different active ingredients and rates of application during the wet seasons of 2009 and 2010 at Rokupr Mangrove Associated Swamp and at Gbomsamba in the Boliland to determine (i) the effectiveness of different rates of application of pre-and post emergence herbicides on weed growth and yield of rice varieties, (ii) identify suitable herbicides for the two ecologies and (iii) the cost benefit of herbicides application. The results showed significantly reduction in weed population with herbicides application (P=.05). Percentage reductions over control ranged from 65 to 91 percent in 2009 and from 68 to 87 percent in 2010. The herbicides Stam (PE), RiceForce (Pe) and ButaForce (Pe) were the most effective in reducing weed population (P=.05). All herbicides treatments gave significantly higher grain yields than control plots. Grain yields increased with increased rates of application but yields from full and three-quarter doses were similar. Yields of the two varieties at Rokupr were similar to Gbomsamba. The three-quarter doses for the herbicides RiceForce (Pe) and ButaForce (Pe) could be considered for higher marginal returns. The herbicide, Stam (PE) though effective in reducing weed population gave low marginal returns. The results suggest that growing a weed competitive variety and a high yielding variety in conjunction with reduce herbicide rates of RiceForce (Pe) and ButaForce (Pe) could be an effective and economical weed management strategy for rice in the Mangrove Associated Swamp and Boliland ecologies in Sierra Leone.

Open Access Original Research Article

Effects of Tillage on Forage Legumes Growth and Subsequent Dry Matter Yields of Corn Planted for Livestock Feeding

I Gusti Made Oka Nurjaya, I Gusti Ayu Mas Sri Agung

Journal of Experimental Agriculture International, Page 616-625
DOI: 10.9734/AJEA/2012/1660

Two field experiments were conducted to find a simple tillage method to introduce centro (Centrosema pubescens Benth.) and calopo (Calopogonium mucunoides Desv.) on native grasslands and to find out the effects of the tillage and legume phase on the growth of subsequent corn planted for livestock feeding.
A 4 x 3 factorial experiment in a randomized complete block design was conducted with three replications. The first factor was the methods of tillage viz. undisturbed, cutting followed two weeks afterwards by glyphosate application at 3.0 kg ha-1 active ingredients (a.i.), burning which was cutting followed after two weeks by burning and conventional tillage. The second factor consisted of three treatments viz. introducing centro, calopo and no legume introduction. After one year, using the same plots and design that had been used in Experiment 1, the Experiment 2 was conducted, by planting corn for cattle feeding.
Cutting the native grasses followed two weeks afterwards by glyphosate application was superior compared to other methods of tillage for the growth of legumes. Combining these treatments with legume inclusion resulted in 300% increase in dry matter of corn planted after the legume phase compared to without legume introduction, with nitrogen absorbtion increased almost seven fold. However there was no difference between using centro or calopo. Nitrogen content of corn stover and nitrogen absorption of corn plants were similar to those in conventional tillage.

Open Access Original Research Article

Development of Quality Protein Maize (QPM) Inbred Lines and Genetic Diversity Assessed with ISSR Markers in a Maize Breeding Program

K. Mbuya, K. K. Nkongolo, R. Narendrula, A. Kalonji-Mbuyi, R. V. Kizungu

Journal of Experimental Agriculture International, Page 626-640
DOI: 10.9734/AJEA/2012/1626

Very few studies have been conducted to develop new quality protein maize (QPM) varieties adapted to various agro-ecological conditions in Africa. Such QPM varieties with high grain yield, genes for resistance to local disease and pests would contribute to increased grain production and to alleviate poverty and malnutrition. During the first step of the QPM breeding program in the DR-Congo, 137 inbred lines were developed and selected in the field based on various agro-morphometric characteristics. Molecular analysis revealed high level of genetic variability among inbreds. The level of polymorphic loci observed with ISSR markers varied between 74% and 80%. Nei’s gene diversity and Shannon’s information index values varied from 0.22 to 0.27 and from 0.34 to 0.41, respectively. The majority of inbred lines were distantly related. In fact, more than 87% of genetic distance values were above 0.50. The genetic distance values among the different parental maize accessions varied from 0.39 to 0.72. Inbred lines from the same parental accession were also not genetically close with genetic distance values varying from 0.28 to 0.59. More importantly, the ISSR data are useful in the selection of inbred lines to be tested for general and specific combining abilities and further development of synthetics.

Open Access Original Research Article

Initial and Residual Effects of Organic and Inorganic Amendments on Soil Properties in a Potato-Based Cropping System in the Bolivian Andean Highlands

J. Aguilera, P. P. Motavalli, M. A. Gonzales, C. Valdivia

Journal of Experimental Agriculture International, Page 641-666
DOI: 10.9734/AJEA/2012/2006

The objective of this study was to determine the effects of applications of organic and inorganic soil amendments on initial and residual soil chemical, physical and biological properties that may affect both short- and long-term soil fertility in a potato (Solanum tuberosum L.)-based cropping system of indigenous rural communities in the Bolivian Andean Highlands (Altiplano). Field experiments were conducted in four representative low and high elevation communities in the semi-arid Central Andean Region of Bolivia from 2006 to 2009. Treatments included a control, and applications of sheep and cow manure, a commercial household/urban compost product, a commercial biofertilizer soil amendment, urea and diammonium phosphate and combinations of these different treatments. Soil samples were taken from all the sites prior to application of treatments and planting of potatoes as well as during the growing season and prior to planting of a subsequent crop of quinoa (Chenopodium quinoa, Willd). Soil pH, soil total organic C, and total N increased due to application of organic fertilizers with or without inorganic fertilizers. Soil inorganic N and Bray-1 P were increased by inorganic fertilizers alone or when combined with organic fertilizers. The residual effect of most of the analyzed soil nutrients was detected in the subsequent growing season. In addition, lower soil bulk density was observed after organic fertilizers were applied with or without inorganic fertilizers and this residual effect persisted for the quinoa crop. In a controlled laboratory incubation experiment, soil potentially mineralizable C and N increased as organic fertilizers application rates rose from 0 to 30 Mg ha-1. These results highlight the importance of a balanced soil fertilization program in this region with use of optimum rates of both inorganic and organic soil amendments to increase short- and long-term soil fertility.

Open Access Original Research Article

Economic Efficiency of Soybean Production in Ogo-Oluwa Local Government Area of Oyo State, Nigeria

A. O. Ajao, L. T. Ogunniyi, A. A. Adepoju

Journal of Experimental Agriculture International, Page 667-679
DOI: 10.9734/AJEA/2012/1253

This study estimated the technical, allocative and economic efficiencies indices and further examined the factors influencing technical efficiency for the sampled soybean farms in Ogo-Oluwa Local Government Area of Oyo State (LGA). The study made use of a cross-sectional data obtained from sampled soybean farmers in the Ogo-Oluwa of Ogbomoso zone of Oyo State Agricultural Development Project (ADP) that were purposively selected because of the higher concentration of soybean farms compared to other LGAs in the zone. Eighty respondents were randomly chosen from a list of soybean farmers obtained from the Apex Farmers Association of Nigeria (AFAN). Data collected was analysed using the stochastic frontier model. The overall technical efficiency was estimated with no effort of broken it down into pure and scale efficiencies. It was observed from the findings that the range of efficiencies index varies great with minimum of 0.827, 0.135 and 0.128 and maximum of 1.0 for technical allocative and economic efficiencies respectively. The mean efficiency which indicate the average potential there in soybean production in the study area 0.94, 0.892 and 0.839 for technical, allocative and economic efficiency respectively. Of 80 soybean farmers involved in the analysis only one was found to be technically allocatively and economically efficient. The measures of relative allocative and technical efficiency provide evidence as to the source of deviations from overall cost-minimising behaviour. Many sampled soybean farms employed the ‘wrong’ input mix, given input prices, so that, on average, costs were 11 per cent higher than the cost minimizing level. However, farms have the potential to reduce their physical input, on average, by 6 per cent, and still produce the same level of soybean output.
In conclusion, there was a great potential to improve the output of soybean farms and save cost if variable inputs were adjusted to the optimal level along the short-run isoquant. Farmer’s age, extension visit and education significantly influence technical, economic and allocative efficiencies respectively. Inefficiency results in large part from allocative rather than from technical inefficiency.

Open Access Original Research Article

Evaluation of Fluazifop-P-Butyl and Propanil for Weed Control in Sesame (Sesamum indicum L.) in Southern Guinea Savanna, Nigeria

E. I. Magani, P. A. Shave, T. Avav

Journal of Experimental Agriculture International, Page 680-689
DOI: 10.9734/AJEA/2012/1606

Aims: To evaluate the effects of rates of the post-emergence herbicides Fluazifop and Propanil for weed control in sesame (Sesamum indicum L.) grown in Makurdi.
Study Design: Randomized Complete Block Design. 
Place and Duration of Study: The trials were conducted in the growing seasons of 2009 and 2010 at the Teaching and Research Farm of the University of Agriculture, Makurdi (07º 41´N and 08º 37´E) in the Southern Guinea Savanna zone of Nigeria.
Methodology: The eight (8) treatments consist of three rates of Fluazifop (0.15, 0.22 and 0.30 kilogram active ingredient per hectare (kg a.i./ha) and three rates of Propanil (0.72, 1.44 and 2.16 kg a.i./ha), hoe-weeded at 3 weeks after planting (WAP) and a weedy check. The sesame seeds (variety “E8”) used for trials was planted by broadcasting on plot sizes of 5m×4m (20m2). The herbicide applications were carried out as post-emergence at 15 days after planting. Fertilizer NPK (20:10:10) was applied at 4 WAP at the rate of 150 kg ha-1 by broadcasting.
Results: The three rates of Fluazifop significantly controlled grasses without any crop injury. However, Propanil controlled both grasses and sedges, but on broadleaf weeds, the effect increased with increasing at 4 WAP. Grain yield was highest (858 kg ha-1) at 0.72 kg a.i./ha of Propanil, that was followed by treatments that received 1.44kg a.i./ha of the same herbicide. The least grain yield (467 kg ha-1) was obtained with the weedy check.
Conclusion: The highest benefit-cost ratio of 3.53 was obtained from Propanil at rate of 0.72kg a.i./ha. This is an indication that Propanil could be used to control weeds in sesame to boost its productivity in the study area.

Open Access Original Research Article

Performance and Carcass Characteristics of Broiler Finishers Fed Different Levels of Poultry Offal Meal and Crayfish Waste Meal as Replacement for Fishmeal

A. R. Asafa, A. D. Ologhobo, I. O. Adejumo

Journal of Experimental Agriculture International, Page 690-699
DOI: 10.9734/AJEA/2012/1786

Aims: There is need to supply birds with the nutrients required in order to maintain normal growth and reproduction. The escalating cost of dietary protein ingredients necessitates the search for alternatives in poultry production. The inclusion of crayfish waste (CW) and poultry offal (PO) in chicken feeds could reduce the cost of dietary proteins. The study evaluated the utilisation of CW and PO as dietary protein sources for chicken production. 
Study Design: One hundred and eighty day-old Marshall broiler chicks were used for the study in a completely randomized design. Proximate composition of the poultry offal meal and crayfish waste was determined using the analytical methods of AOAC (1996). Data generated were subjected to analysis of variance and significant treatment means were separated using Duncan Multiple Range Test.
Place and Duration of Study: The study was carried out in the Poultry Section of the Teaching and Research Farm of the Lagos State Polytechnic, Ikorodu. The study lasted for nine weeks (five weeks for the starter period and four weeks for the finisher period). 
Methodology: One hundred and eighty day-old Marshall broiler chicks were used for the study. Thirty chicks were assigned to each dietary treatment, which was replicated three times in a completely randomized design. Six experimental diets containing fish meal (FM), crayfish waste meal (CWM) and poultry offal meal (POM) were used thus: control diet which was diet 1 contained 2.1% FM of the total ingredients, while diets 2,3,4,5 and 6 contained 2.79% POM, 3.92%CWM, 2.09% POM + 0.98%CWM, 1.40% POM + 1.96% CWM, and 0.69% POM + 2.94%CWM, respectively. Birds were fed the starter diets for five weeks after which the finisher diets were fed for four weeks.
Results: The CWM contained 35.0, 12.9 and 3.9% CP, CF, and EE, respectively and 1454Kcal/kg ME, while the POM contained 51.9, 1.8 and 6.2% CP, CF and EE correspondingly with 2600Kcal/kg ME. However, FM contained 65.1, 0.8 and 6.0% CP, CF and EE with corresponding ME of 2860Kcal/kg. The control birds (diet 1) and diet 6 consumed 2.98kg similar to diets 2 (2.97kg) but differed significantly (P =0.05) from those on diets 3, 4, and 5. The protein efficiency ratio (PER) and feed conversion ratio (FCR) were similar for all treatments. Chicken fed diet 3 had an eviscerated weight of 84.27% which was significantly (P=.05) better than others. 
Conclusion: Diets 4 and 6 which contained 2.09%POM: 0.98% CWM and 0.69% POM: 2.94% CWM respectively were identified as the most cost effective treatments and selected as the best inclusion levels.