Open Access Short communication

Beans Genotypes (Phaseolus vulgaris L.) of the Black Group in the Cerrado Environment, Brazil

P. O. A. S. Guedes, E. M. Biesdorf, G. R. Santos, M. Elivelton Biesdorf, A. Andrade

Journal of Experimental Agriculture International, Page 1-10
DOI: 10.9734/JEAI/2017/35023

Beans are considered one of the most economically important agricultural crops in Brazil. However, the country is not yet self-sufficient in this crop, importing still about 10% of the beans consumed. The objective of this study was to evaluate the performance of seven black bean cultivars under the soil and climatic conditions of the Brazilian cerrado. The experiment was carried out under a randomized block design, with three replicates. Seven cultivars of black beans were tested: i) BRS Campeiro, ii) BRS 7762 Supremo, iii) BRS Esplendor iv) CNFP 10104, v) CNFP 10793, vi) CNFP 10794 and vii) CNFP 10806). Plant architecture, planting, number of days to flowering and number of days to harvest, as well as the final population of plants, grain yield per plant, yield and weight of 100 grains were evaluated. The varieties tested did not present significant differences in relation to the architecture and the lodging degree. In addition, the number of days to flowering, as well as the number of days to harvest, had little variation among the tested cultivars. However, cultivars CNFP 10104 and CNFP 10793, although they did not show a significant statistical difference compared to the other cultivars in relation to the final population of plants and production per plant, presented the highest yields (kg ha-1) and also the highest values for the Weight of 100 grains. It is concluded that the cultivars CNFP 10104 and CNFP 10793 are those with the greatest potential for use in the soil and climatic conditions of the cerrado of Brazil.

Open Access Original Research Article

Roots Partially Drive Super Sweet Maize Yield

J. Rattin, P. Wagner, D. Ferreyro, A. Riverti, E. Giardina, A. Di Benedetto

Journal of Experimental Agriculture International, Page 1-17
DOI: 10.9734/JEAI/2017/33959

Although it has been indicated that corn biomass accumulation between sowing and harvest are directly related to incident photosynthetically active radiation (PAR) intercepted by the canopy, plant roots can sense soil environment and, via some internal signal, transmit the condition of the soil to extending leaves. Experiments combined two plant densities, a transplant routine and a single benzyl aminopurine (BAP) spray on different super sweet maize hybrids to test the hypothesis that a changes in both light and root environments drive super sweet maize yield. Pot experiment showed a close coordination between roots and shoot growth while field experiments support the proposed hypothesis through the positive relationships between RLAE, CGR and yield and root dry weight. This novelty approach would indicate that root growth could be considered as a limiting factor to shoot growth and yield in super sweet maize crops.

Open Access Original Research Article

Growth Rate and Disease Resistance of Inbreds and Novel Intra-specific Crossbreds Larva of Clarias gariepinus (Burchell, 1822) in Response to Pseudomonas aeruginosa Challenge

O. O. Oyebola, O. M. Adekunle, S. B. Setufe

Journal of Experimental Agriculture International, Page 1-11
DOI: 10.9734/JEAI/2017/32653

Aim: To assess the differences in survival rate and Growth Rate (GR) in larva of novel inbred (CC) and crossbred (CS and SC) genotypes of C. gariepinus in response to P. aeruginosa disease challenge, in order to explore their potentials for improved aquaculture.

Study Design: Completely Randomized Block Design.

Place and Duration of Study: Department of Aquaculture and Fisheries Management, University of Ibadan, Nigeria, between June and November, 2015.

Methodology: Sixty individuals of four weeks old C. gariepinus inbred-CC (individuals not possessing serration at anterior portions of  both sides’ pectoral spine-C) and SS (Individuals possessing the serrations-S) and crossbred-SC (maternal-S x paternal-C) and CS (maternal-C x paternal-S) strains were immersed in 500 ml water containing 0.01ml of 2.56x107 cfu/ml P. aeruginosa inoculums for 30 minutes. Challenged and control treatments were reared in freshwater for two weeks. Specimens were monitored for clinical signs, survival (%) and growth rate during 2weeks post challenge rearing period.

Results: At P= .05, values of survival and growth rates were significantly different across genotypes as well as across control and challenged treatments of each genotype. Fish from challenged treatments were sluggish, lost appetite, and had hemorrhage. 100% challenged-SC and 20.62±1.15% challenged-CC died within 72 hours; during this period, all control treatments, challenged-CS and challenged-SS survived. At 2weeks, survival rates (%) were higher in control than challenged SC (37.5±17.7:0.00) and CC(77.5±3.5:25.0±5.5), but similar (100%) in SS and CS. GR was 0.02±0.00 in control-SC. GR were significantly higher in challenged compared to control in CC, SS and CS: 0.20±0.01: 0.01±0.00, 0.46±0.03: 0.26±0.01 and 1.05±0.12: 0.33±0.02 respectively.

Conclusion: Paternal serrated crossbreed (CS) of C. gariepinus tolerated P. aeruginosa infection with superior survival and growth rate, thus indicating high potential for aquaculture in the face of the disease challenge, while maternal serrated crossbreed (SC) was highly susceptible

Open Access Original Research Article

Effects of Landscape Slope Position, Urban Refuse Compost and Sewage Sludge on Soil Properties and Cassava Yield in South Eastern Nigeria

R. A. Ezema, M. E. Obi, C. L. A. Asadu, T. E. Omeje, R. S. Agu, O. J. Uche, Okoro Alex, O. N. Udegbunam

Journal of Experimental Agriculture International, Page 1-10
DOI: 10.9734/JEAI/2017/32356

Understanding the effects of landscape slope position and organic waste residues on soil properties and cassava yield is a critical component of site-specific management. A field study was conducted in an Ultisol at Nsukka, southeastern Nigeria to investigate the effects of landscape slope positions and two organic waste residues (urban refuse compost and sewage sludge) on soil properties and cassava yield. The treatment consisted of two landscape slope positions, two organic waste residues, and a control; arranged in a split – plot design in RCBD. The two slope positions - mid slope (26%) and toe slope (5%) occupied the main–plot, while organic residues at the rate of 50% inorganic nitrogen fertilizer requirement of cassava and a control were the sub-plot treatment. The result obtained from this study showed that slope position significantly (p<0.05) influenced the soil properties after harvest. The toe-slope soil was significantly (p<0.05) higher in dry bulk density, water holding capacity, field capacity moisture content and more resistant to mound dispersion by rain drops. The mid-slope soil was significantly (p<0.05) higher in percent water stable aggregates. There was significant difference (p<0.05) between the non-amended plots and the organic wastes amended plots in respect of aggregate stability as measured by percent water stable aggregate (% WSA) index. Post-harvest soil analysis revealed that plots amended with urban refuse compost (UR) and sewage sludge (SS) did not differ significantly in their pH, total porosity, bulk density, water holding capacity, field capacity moisture content, saturated hydraulic conductivity and mound dispersion as measured by length of exposed nail. Weed infestation, fresh shoot and root yield were significantly (p>0.05) higher at the toe slope position. However, percent survival was significantly (p>0.05) higher at mid slope position. Significant interactions of the slope positions and organic residues were observed in bulk density, total porosity and fresh root yield. The highest fresh cassava root yield of 11.63 tha-1 of the study was obtained in plots amended with urban refuse compost under the toe slope position. Urban refuse compost had the least fresh root yield per hectare (1.32 tha-1) when applied in midslope landscape position but highest (11.63 tha-1) when applied in toe-slope landscape position.

Open Access Original Research Article

Distribution of Sulphur in Some Soils of Meghalaya

Arup Sen, Joseph Mukhim, Abhijit Debnath, Prashanta Barman

Journal of Experimental Agriculture International, Page 1-9
DOI: 10.9734/JEAI/2017/34255

A study was undertaken to generate information on the distribution of different forms of sulphur in the soils of Meghalaya. Surface soils (0-15 cm) were collected from 10 (ten) different locations comprising 3 districts viz., Jaintia hills, East Khasi, and Ribhoi districts of the State of Meghalaya belonging to three soil orders. Soils from Meghalaya were acidic in nature with mean pH value being 5.49. The organic carbon contents were in general medium with mean value of 0.703 and texturally the soils varied from Sandy to Clay loam. The available P was in general medium to high. The soils of Meghalaya have adequate available S.

The water soluble S had a mean value of 6.19 mg kg–1 soil for Meghalaya. Sulphate S varied between 2.89 and 4.02%. The fraction is low probably because of coarse soil texture thereby leading to its leaching. This fraction exhibited a significant negative correlation with pH and positive correlation with organic C. The adsorbed S fraction had a mean value of 15.2 mg S kg–1 soil contributing 2.35 to 4.23 percent of total S. The non-sulphate S had a mean value of 111.7 mg kg–1 soil and constituting the second largest fraction. The organic S averaged 324 mg kg–1 soil and contributed about 63.18 to 76.45% of total S. Organic S had a significant positive correlation with organic C, total N, and all form of S except non-sulphate S (NSS). The soils of Meghalya are, in particular, high in native S content.