Open Access Original Research Article

Temporal Dynamics of Napier Grass Stunt Disease as Influenced by Napier Grass Clones and Initial Inoculum

Geofrey Kawube, Herbert Talwana, Titus Alicai, Michael Otim, Anthony Mukwaya, Jolly Kabirizi

Journal of Experimental Agriculture International, Page 268-279
DOI: 10.9734/AJEA/2015/17532

Napier grass stunt disease (NGSD) is the main biotic factor limiting Napier grass production in the East African region. Its management is, however, hampered by inadequate epidemiological information. This study determined the temporal spread of NGSD in Napier grass fields. A field experiment was setup at National Crops Resources Research Institute, Namulonge in Uganda to determine the influence of initial inoculum and clones on the spread of NSD in the field. The experiment was arranged in a randomized Complete Block Design and replicated 4 times. The initial inoculum levels used were 0%, 10%, 20% and 30% while the clones included KW4, local/wild type and P99, respectively. Napier grass stunt disease incidence data was recorded at 60 days intervals starting 90 days after planting up to 450 days. Napier grass was cut back to a height of 5 cm above ground after each data collection. Gompertz model was found to adequately describe NGSD temporal spread, the basis on which all incidence data was transformed. Results indicate that NGSD symptoms appeared in the field after 150 days after planting. However, NGSD incidence at the time was influenced by initial inoculum levels and type of clone. Plots with higher levels of initial inoculum density reached epidemic levels faster than those without. Disease incidence increased with increase in levels of initial inoculum and time, doubling after every 13.8 to 29.8 days, as such the rate of disease spread is moderate. The disease progression was fastest in clone P99 followed by KW4 and least in local. Final NGSD incidence and Area Under Disease Progress Curve (AUDPC) were linearly related with the NGSD incidence at the time the disease was first detected; indicating that incidence at NSD detection can be used to predict the final disease and AUDPC in the field. Therefore, deployment of measures that reduce initial inoculum is important in control of the disease.

Open Access Original Research Article

Evaluation of Genetic Diversity in Agromorphological Traits of Forty Two Aman Rice Genotypes (Oryza sativa L.) Using D2 Analysis

G. Sarwar, M. H. Rashid, S. Parveen, M. S. Hossain

Journal of Experimental Agriculture International, Page 280-288
DOI: 10.9734/AJEA/2015/17138

The experiment was conducted with forty two genotypes of rice at the experimental farm of Sher-e-Bangla Agricultural University, Dhaka during the period of July 2013- December 2013 to estimate the diversity among 42 Aman rice genotypes. Based on D2 analysis the genotypes were grouped into five different clusters. Clusters IV had the maximum fourteen and cluster III had the minimum three genotypes. The highest inter-cluster distance was observed between II and III and the lowest was between IV and V. The highest and lowest intra-cluster distance was observed in III and IV respectively. Genotypes included in cluster V were important for total tillers per plant, effective tillers per plant, days to 50% flowering and thousand grains weight; cluster III were important for filled grains per panicle and unfilled grains per panicle; cluster IV were for plant height and yield per plant. Considering the diversity pattern and other agronomic performances, the genotypes Special from AL-29, AL-36, PP-4B(i), AL-17(iii)B, AL-17(iii), AL-17(ii)A, Special from-129, Special from 17(iv), AL-44(i), AL-17, Special from AL-36(D), PP-48, IR-25B, Special from AL-33, IR-25B (Tall), P-5B might be considered better parents for the future efficient hybridization programme.

Open Access Original Research Article

Use of Selected Herbicides and Application Methods for Tolerance to Tifton 85 Bermudagrass [Cynodon dactylon (L.) Pers.]

Travis W. Janak, Paul A. Baumann, Sara E. Janak, W. James Grichar

Journal of Experimental Agriculture International, Page 289-298
DOI: 10.9734/AJEA/2015/17727

Aims: To evaluate forage tolerance of Tifton 85 bermudagrass to selected pasture herbicides using two application methods: broadcast (BRD) and individual plant treatments (IPT).
Study Design: A randomized complete block design was employed with four replications.
Place and Duration of Study: Trials were conducted during the 2006 and 2007 growing seasons near Thrall, Texas, (30.35o N, 97.17o W).
Methodology: Two spray application methods (BRD and IPT) were compared when using selected herbicides for bermudagrass tolerance. Herbicides evaluated by BRD included picloram plus fluroxypyr, picloram plus fluroxypyr plus metsulfuron-methyl, triclopyr, triclopyr plus fluroxypyr, triclopyr plus metsulfuron-methyl, triclopyr plus fluroxypyr plus metsulfuron-methyl, and metsulfuron-methyl plus dicamba plus 2,4-D. Herbicides evaluated by IPT included triclopyr, triclopyr plus fluroxypyr, and picloram plus fluroxypyr. Bermudagrass injury, yield, and crude protein content were evaluated for application method and herbicide.
Results: Rainfall after herbicide application in 2006 was 67% below normal while in 2007 rainfall was 350% above normal. No bermudagrass necrosis or growth reduction were noted in 2006. Triclopyr plus fluroxypyr applied IPT was the only treatment to decrease Tifton 85 dry matter yield at the first harvest, with no effect observed at the second. In 2007, necrosis was greatest with triclopyr plus fluroxypyr applied BRD while triclopyr plus fluroxypyr and triclopyr plus fluroxypyr plus metsulfuron-methyl applied BRD and triclopyr applied IPT caused the greatest growth reduction. Triclopyr and triclopyr plus fluroxypyr applied BRD or IPT and triclopyr plus fluroxypyr plus metsulfuron-methyl applied BRD decreased dry matter yield at the first harvest while only triclopyr alone applied IPT reduced yield at the second.
Conclusions: The recurring bermudagrass stunting and yield reduction with triclopyr is consistent with previous forage tolerance research. Metsulfuron methyl plus dicamba plus 2,4-D was the only treatment that exhibited little or no injury, growth reduction, or yield reduction at any time. Producers need to be aware of potential injury issues with triclopyr.

Open Access Original Research Article

Effect of Urban Flood Waters and Sediments on the Presence and Levels of Heavy Metals in Valley Bottom Soils of Ekpoma Metropolitan, Southern Nigeria

O. O. Eghaghara, M. Ebhangbe, S. O. Dania

Journal of Experimental Agriculture International, Page 299-306
DOI: 10.9734/AJEA/2015/16502

An experiment was conducted on some selected valley bottom soils in Ekpoma metropolitan, to investigate the presence and levels of heavy metals as affected by urban flood waters and sediments. Three sites were chosen for the investigation: Ambrose Alli University Teaching and research farm, Ekpoma (AAU), Emaudo (EM) and Uhiele (UH) quarters. AAU was used as control since it received no flood waters and sediments. At each site, a plot (25m x 25m) was demarcated for soil sample collection. Within each plot five spots were randomly chosen and soil samples were augered at two depths (0-15 cm and 15-30 cm), making ten samples per site. Samples were bagged, labelled and taken to the laboratory for analysis. The following metals were investigated – Mn, Pb, Co, Ni, Fe, Cd, Cu, Zn. Some chemical and physical properties were also investigated. Results were analysed statistically using (ANOVA) to determine significant differences between treatment means (p=0.05) and LSD was used to separate the means. Results revealed soils of Uhiele to be sandy clay loam, while Emuado and A.A.U were sandy loamy. pH values for all the sites and depths showed that the soils were acidic. Values for organic matter for the two sites were significantly higher (p=0.05) when compared to the control AAU. For heavy metals, the levels were below risk level for all the sites. All the metals showed increased values except Cobalt and Nickel, compared to the control (A.A.U). This experiment confirmed increase levels of heavy metals in valley bottom soils of Ekpoma metropolitan that regularly receive flood waters and sediments. Since anthropogenic activities will always be there, and with uncontrolled waste disposal systems, it is recommended that levels of heavy metals in these cultivated valley bottom soils be periodically monitored, so as to detect when the levels will pose health risk for those who may consume harvested products from these soils.

Open Access Original Research Article

Effect of Probiotic, Carbohydrase Enzyme and Their Combination on the Performance, Histomorphology and Gut Microbiota in Broilers Fed Wheat-based Diets

A. F. Agboola, O. Odu, B. R. O. Omidiwura, E. A. Iyayi

Journal of Experimental Agriculture International, Page 307-319
DOI: 10.9734/AJEA/2015/16997

The effect of supplementation of probiotic and/or carbohydrase on performance and gut health in broiler chickens was studied.
Diet 1 was the basal diet with no supplement while diets 2, 3, 4 and 5 were supplemented with antibiotic, probiotic, carbohydrase and combination of probiotic and carbohydrase, respectively in a randomized complete block design.
The experiment was carried out at the Poultry Unit of the Teaching and Research Farm, University of Ibadan, Nigeria between March and April, 2013. 240 one-day-old broiler chickens were allotted to 5 diets with 6 replicates of 8 birds each in a 35-day experiment. On day 35, birds were sacrificed and digesta samples from the duodenum, ileum, caecum and colon were collected for microbial load count. Digesta viscosity and pH from the ileum were also determined. Sections of the ileum were obtained for morphological measurements.
Result showed that diet had no effect on the feed intake, dry matter intake and feed conversion ratio of birds at starter (d 0-21), grower phases (d 22-35) and overall period (d 0-35). Body weight gain was significantly (P = .05) improved at d 0-21 and 22-35 with the addition of probiotic and/or carbohydrase but not at d 0-35. Diet had no effect on the microbiota in the various segments of the GIT of birds. Coliform counts of birds fed diet supplemented with carbohydrase were significantly (P = .05) higher (5.64 x 106 cfu/ml) than the values in other diets. The crypt depth, villus height, villus width and villus height:crypt depth ratio were not affected by diet. Highest digesta viscosity (1072mPa) was recorded in birds on the negative control while the least digesta viscosity (529mPa) was observed in birds on diet supplemented with carbohydrase enzyme.
It is concluded that probiotic and/or carbohydrase are viable feed supplements in wheat-based diets for broilers.

Open Access Original Research Article

Nutrient Digestibility and Growth Performance of Finisher Broilers Given Dried Xylopia aethiopica Fruits (Grains of Selim) as Additive

J. O. Isikwenu

Journal of Experimental Agriculture International, Page 320-326
DOI: 10.9734/AJEA/2015/17377

The nutrient digestibility and growth performance of finisher broilers given dried Xylopia aethiopica fruits (grains of selim) as additive was investigated. One hundred and ninety five finisher broilers (Arbor acres strain), 28- days old were randomly assigned into five treatments with each treatment having three replicates. Blended grains of selim was administered orally through drinking water on treatments 2, 3, 4 and 5 at concentrations of 0.4, 0.6, 0.8 and 1.0 g per litre respectively while birds on treatment 1 (control) received 0.3 g/litre of antibiotics (doxygen). Birds were fed ad libitum with the same isoproteinous and isocaloric diet containing 20% crude protein and 2905.95 Kcal/kg metabolisable energy for 28 days. Results showed no significant differences among treatments in the final body weight, total weight gain, daily weight gain, total feed intake, daily feed intake and feed conversion ratio. Nutrient digestibilities were similar across treatment groups. Results of this study demonstrated that grains of selim could be used as a substitute for antibiotic growth promoters.

Open Access Original Research Article

Effect of Replacement of Soybean Meal with Leucaena leucocephala Leaf Meal on Performance, Haematology, Carcass Measures and Organ Weight in Broiler Chickens

F. O. Eichie, D. E. Akinyemi, M. Adegbenro

Journal of Experimental Agriculture International, Page 327-334
DOI: 10.9734/AJEA/2015/17125

This study was carried out to determine the effect of replacing soybean meal (SBM) with Leucaena leucocephala leaf meal (LLM) in the diet of broiler chickens. One hundred and fifty one-day-old broiler chicks were allotted to five treatments, each with three replicates and ten birds per replicate in a completely randomized design. The experiment was carried out at the University Teaching and Research Farm, Federal University of Technology Akure. The feeding trial lasted for 8 weeks. The treatments were Diet 1 (control, without LLM replacement) and Diets 2, 3, 4, and 5 where soybean meal (SBM) was replaced by 25%, 50%, 75%, and 100% of LLM, respectively from 0-56 days of rearing. Substitution of SBM with LLM significantly (P < 0.05) influenced the performance of broilers from day 0-28, but not at 29-56 days. Body weight gain of 907 g was obtained in birds on Diet 3 (50% LLM), while the least value of 553 g was obtained for Diet 5 with 100% LLM. The diet containing 50% LLM had better FCR (2.66) than the other treatments. Substitution of SBM with LLM did not significantly influence the haematological parameters except Erythrocyte Sedimentation Rate (ESR) concentration, which was significantly (P < 0.05) affected. Organ weights were not affected by diet from 0-28 days but from 29-56 days, weights of organs were significantly (P < 0.05) reduced as the level of LLM in diet increased. Carcass parts were significantly (P < 0.05) reduced by dietary LLM at 0-28 and 29-56 days, except for the back, drumstick, neck, head and shank that were not affected by LLM. Results of the study showed that LLM could be used to supplement SBM up to 50% in the diets of broiler chickens to improve performance and without adverse effect on the birds.