Open Access Original Research Article

Estimating Light Interception by Cotton Using a Digital Imaging Technique

Evangelos D. Gonias, Derrick M. Oosterhuis, Androniki C. Bibi, Larry C. Purcell

Journal of Experimental Agriculture International, Page 1-8
DOI: 10.9734/AJEA/2012/879

Radiation intercepted by the crop canopy is directly correlated to dry matter accumulation. Calculation of fractional light interception by the crop is commonly performed by measuring photosynthetically active radiation above and below the canopy using a line-source quantum sensor. However, this method is limited by the time of measurement and the presence of clouds. For soybeans grown in 19-cm rows, ground coverage values estimated from digital images taken above the canopy have been correlated to light interception measurements, but there have been no reports of using this method in cotton or in other crops on wide rows. In this study, a digital imaging technique was used to establish a relationship between fractional canopy coverage and fractional light interception for cotton. This study suggests that digital imagining may be used as an alternative technique for estimating light interception by cotton.

Open Access Original Research Article

Molecular Characterization of Non-flowering Perennial Sorghum spp. Hybrids

R. W. Jessup, D. K. Whitmire, Z. L. Farrow, B. L. Burson

Journal of Experimental Agriculture International, Page 9-20
DOI: 10.9734/AJEA/2012/897

Aims: The goal of this study was to characterize recently identified, non-flowering, putative tetraploid Sorghum spp. hybrids utilizing bulked segregant analysis with SSRs and compare them to S. bicolorS. halepense, and triploid putative Sorghum spp. hybrids. Confirmed species hybrids between S. bicolor and S. halepense would provide resources for investigating risks of invasiveness and transgene escape alongside potential for identifying novel perennial Sorghum feedstocks of value. 
Study design: Bulked segregant analysis of Sorghum species and S. species hybrids.
Place and Duration of Study: Department of Soil & Crop Sciences; Texas A&M University; College Station, TX, USA; 2009 - 2011
Methodology: A bulked segregant analysis approach was conducted using SSRs mined from the S. bicolorgenome sequence. Bulked samples of S. bicolor, typical flowering S. halepense, non-flowering tetraploid putative Sorghum spp. hybrids, and triploid putative Sorghum spp. hybrids were surveyed to identify both unique markers specific to each bulk and markers indicative of S. bicolor genetic material introgressed into the Sorghum spp. hybrids. 
Results: Thirty-nine and 23 markers were found to be unique to the S. bicolor and typical flowering S. halepense bulks, respectively. These unique markers could be utilized in breeding programs to identify interspecific hybrids. A subset of 23 unique SSRs were found in the non-flowering tetraploid putative Sorghum spp. hybrid, and they may be useful in the characterization of the non-flowering phenotype.
Conclusion: Markers identified in this study provide: 1) species-specific tools for confirmation of interspecific Sorghum spp. hybrids and quantification of gene flow between Sorghum spp., 2) candidate gene and genomic region resources for dissection of the non-flowering phenotype, and 3) Sorghum spp. hybrid-specific markers suitable towards development of perennial biofuel and forage sorghum feedstocks.

Open Access Original Research Article

Fermentation Characteristics, In Situ Rumen ‎Degradation and Aerobic Stability of Whole Crop ‎Barley Ensiled with Urea or Aqueous Ammonia

Moosa Vatandoost, Mohsen Danesh Mesgaran, AliReza Vakili

Journal of Experimental Agriculture International, Page 21-30
DOI: 10.9734/AJEA/2012/811

Various chemical compounds might be added to forage to maintain or ‎improve the quality value of a crop ensiled. The aim of the present experiment was to evaluate the fermentation characteristics, in situ ‎rumen degradation and Aerobic Stability ‎of whole crop barley ensiled with Urea or aqueous Ammonia.‎‎ In the ï¬rst experiment, Whole crop barley was harvested (35% DM), chopped, and then ensiled using laboratory silos (n= 4) as untreated (UT) or treated with urea (10, 20, 30 and 40 g kg-1 DM; U1, U2, U3 and U4, respectively) or aqueousammonia (10 and 20 g kg-1 DM; A1 and A2, respectively) for 30 days. Standard procedures were used to determine the chemical composition of the samples. The pH of the aqueous silage extract was determined using a pH meter. Ammonia-N concentration was determined in acidified silage extract (5 ml of the extract + 5 ml of 0.2 M HCl) using a distillation method. Four sheep (live weight: 44±3 kg) fitted with rumen fistulae were used. Approximately 5 g DM of each sample was placed in a polyester nylon cloth bag (10 × 12 cm, pore size of 52 µm, n=4), then incubated in the rumen for 0.0, 2, 4, 8, 16, 24, 48, 72 and 96 h. Rumen removal bags were washed in cold running water and dried in oven (60 °C, 48 h), then weighted to determine DM disappearance. The equation of P= a+b (1-e-ct) was applied to determine the coefficients (a= quickly degradable fraction, b= slowly degradable fraction, c= fractional degradation rate constant). Both urea and anhydrous ammonia caused a significant (P <0.05) increase in silage pH and NH3-N, and CP concentrations. The slowly degradable fraction (b) of the silage treated with urea was significantly (p <0.05) higher than those of the untreated sample. Potential degradability of U4 was higher than other treatments. In a second experiment, whole crop barley was harvested (32.5% DM), chopped, ‎and then ‎ensiled (n= 4) for 35 days as untreated (UT) ‎or treated with urea (23.4 g Kg-1DM) or ‎aqueous ammonium (13.1 g Kg-1DM), to obtain a ï¬nal application rate of about 0.35% N ‎of fresh forage weight. The population of yeasts and molds (colony-forming unit= CFU) was determined by spread plating of filtered extract silages on malt extract agar. Aerobic stability was deï¬ned as the time it took for the temperature in the silage masses to rise 2 °C above ambient temperature. Whileboth of urea and ammonia had no effect on the initial number of mold in the silages, these treatments significantly lowered CFU of yeast in fresh silages. In this experiment both Ammonia and urea had a significant effect on inhibition of rising temperature and yeast in aerated silages. Urea and ammonia treatments significantly enhanced ‎aerobic stability of silages.

Open Access Original Research Article

Sire Genetics, Protein Supplementation and Gender Effects on Wool Comfort Factor in Australian Crossbred Sheep

A. E. O. Malau-Aduli, J. D. D. Akuoch

Journal of Experimental Agriculture International, Page 31-46
DOI: 10.9734/AJEA/2012/943

Aims: To investigate the effects of sire genetics, nutrition, level of supplementation, gender and their interactions on wool comfort factor (CF) and its correlation with other wool quality traits in crossbred sheep either grazing or supplemented with dietary protein.
Study design: A 5 x 2 x 2 x 2 factorial experimental design comprising five sire breeds, two dietary protein sources, two supplementation levels and two sexes respectively, was utilized. 
Place and Duration of Study: University of Tasmania Farm, Cambridge, Hobart, Tasmania, Australia, between April 2008 and November 2010.
Methodology: Texel, Coopworth, White Suffolk, East-Friesian and Dorset sires were joined with 500 Merino ewes at a mating ratio of 1:100 in individual paddocks. Five hundred of the crossbred progeny were raised on pastures until weaning at 12 weeks of age. Forty of the weaners with an initial body weight (BW) range of 23-31 kg (average of 27 ± 3.2 kg) were fed with lupins or canola at 1 or 2% BW for 6 weeks in individual metabolic crates. CF and other wool quality traits were commercially measured at the Australian Wool Testing Authority, Melbourne. The data were analyzed in SAS using MIXED model procedures with sire fitted as a random effect, while sire breed, nutrition, supplement, level of supplementation and gender and their interactions were fitted as fixed effects.
Results: CF was significantly correlated with fiber diameter (-0.89), spinning fineness (-0.95) and wool curvature (0.33). Grass-fed sheep produced wool with significantly higher comfort factor (93.1±0.3%) than supplemented sheep (CF=85.9±1.1%). Sire genetics was a significant source of CF variation; White Suffolk crosses had the highest CF (90.1±8.7) and East-Friesian crosses the least (81.5 ± 10.1%). Males fed canola at 1%BW had the highest CF (90.8 ± 7.0%), while females fed lupins at 1% BW had the least (81.1±10.8%). 
Conclusion: From a practical point of view, sheep farmers engaging in prime lamb production with wool comfort factor as an additional breeding objective should concentrate their effort on grass-feeding White Suffolk x Merino wethers. During the winter feed gap, supplementing the wethers with canola at 1% BW will not compromise wool CF.

Open Access Original Research Article

Analysis of Determinants of Farm Size Productivity among Small- Holder Cassava Farmers in South East Agro Ecological Zone, Nigeria

H. N. Anyaegbunam, P. O. Nto, B. C Okoye, T. U. Madu

Journal of Experimental Agriculture International, Page 74-80
DOI: 10.9734/AJEA/2012/682

Aims: To examine the socioeconomic characteristics of the farmers and determinants of farm size productivity among small-holder cassava farmers.
Study design: Time series data.
Place and Duration of study: The study was carried out in 2009 in the south-east agro ecological zone of Nigeria. April-June, 2009.
Methodology: A multistage randomized sampling method was used in selecting four states – Abia, Akwa Ibom, Imo and Cross River and then 240 cassava farmers in the area of study. Structured questionnaire and interview schedule were used to elicit information from the respondents. Information sought bordered on the socioeconomic characteristics of the respondents and input use. Analysis of data was carried out using log-linear regression model and descriptive statistics such as tables, percentages and mean.
Results: The results revealed that farm size was negative and significant at 1% and productivity of cassava increases with hired labour which is positively correlated with productivity at 1% level of probability. The coefficient of mode of occupation was positively correlated to productivity at 5%. It signifies that full time farmers are more productive than part time farmers. 
Conclusion: The results have shown that there is an inverse relationship between farm size and productivity. This call for policies aimed at redistribution of land targeted towards giving land to small-holder farmers in order to improve productivity.

Open Access Original Research Article

Comparing Liquid and Solid Media on the Growth of Plantlets from Three Kenyan Potato Cultivars

Miriam Mbiyu, Jane Muthoni, Jackson Kabira, Christine Muchira, Patrick Pwaipwai, Joseph Ngaruiya, John Onditi, Susan Otieno

Journal of Experimental Agriculture International, Page 81-89
DOI: 10.9734/AJEA/2012/715

Tissue culture has been used to produce high quality and clean planting material. In addition to viral elimination, tissue culture offers other advantages such as rapid multiplication of seed stock for basic seed production within a short period of time. The method is also useful for germplasm conservation. Although, in-vitro multiplication of potato was started 40 years ago and is promising, extensive use in developing countries has been limited by the high costs of media. There is thus need to explore cheaper alternatives without compromising on quality of in -vitro plantlets. A study was carried out to compare the effects of the liquid medium and solid medium on performance of three popular Kenyan potato cultivars i.e. Dutch, Kenya Sifa and Tigoni. Liquid medium consisted of Murashige and Skoog medium supplemented with normal vitamins and sucrose while solid medium consisted of the same chemicals into which phytagel were added to solidify the medium. Data taken were number of roots, nodes and leaves per plantlet over time. From the results, the liquid medium gave more roots, more nodes and more leaves per plantlet than the solid medium. The results therefore indicated that liquid media have a significant effect on the plant growth. In addition, liquid medium was found to be cheaper than solid media by USD 1.65. It appears more economical to use liquid media than solid media for in vitro micro-propagation of potato. However, the experiment needs to be repeated especially with different potato cultivars so as to come up with useful recommendations.

Open Access Original Research Article

Physiological Performance of Wheat and Barley Seeds Treated with Bioactivator

Andreia da Silva Almeida, Luciana Regina Lauxen, Francisco Amaral Villela, Geri Eduardo Meneghello, Maria Ângela André Tillmann

Journal of Experimental Agriculture International, Page 90-101
DOI: 10.9734/AJEA/2012/685

Considering the climate and soil, as well as the results achieved by breeding, different regions show a high potential for wheat and barley production. The insecticide thiamethoxan has shown positive effects on increasing the expression of vigor and biomass formation, the elevation of photosynthetic rate and increase the formation of deeper roots. The aim of this study was to evaluate the thiamethoxan influence in the physiological performance of wheat and barley seeds. It was used seeds of two wheat and barley cultivars, and product concentrations of 0.0, 150, 300, 450, 600 ml of thiamethoxan to 100 kg of seeds. To evaluate the physiological quality of seeds, it was conducted the tests of germination, first count, cold, lengths of seedlings, shoots and roots and emergence in field. The product tiamethoxan stimulates the physiological performance of wheat and barley seeds, with varying intensity according to cultivar. Doses of 300 to 400 ml of product per 100kg of seeds were more effective in promoting the expression of the physiological performance of the wheat and barley seeds.

Open Access Original Research Article

Productivity and Technical Efficiency among Beneficiary Farmers of Second National Fadama Project in Kaduna State, Nigeria

J. B. Simonyan, J. O. Olukosi, R. A. Omolehin, T. K. A. Atala

Journal of Experimental Agriculture International, Page 102-110
DOI: 10.9734/AJEA/2012/854

The study evaluates the productivity and technical efficiency among beneficiary farmers of Second National Fadama project in Kaduna State, Nigeria. Data for analysis were obtained from two hundred and six project beneficiary and non beneficiary farmers respectively. Descriptive statistic, pie chart and stochastic frontier production function were used for the data analysis. The study revealed that fertilizer and pumping machine rated high among the Fadama II project facilities used by the beneficiary farmers. Evidence from the stochastic production analysis shows that Farm size, fertilizer and hired labour were highly significant (1%) in determining the output of project beneficiaries, while chemical, farm size and fertilizer were significant at 1% respectively in determining the output of the non-beneficiary farmers in the study area. The mean technical efficiency of the project beneficiary was higher (92%) than the mean technical efficiency (48%) of the non-beneficiaries. Age, educational level, Fadama farming experience and access to credit were positively related to technical efficiency of project beneficiary at 1% respectively. The study recommends policies that aimed at improving beneficiaries’ access to credit, timely distribution of productive inputs. This in turn would help the country to ensure all year round food production and reduction in poverty level among its populace.

Open Access Original Research Article

Response of Local Cassava Varieties in Uganda to Cassava Mosaic Virus Disease

J. Adriko, W. S. Sserubombwe, E. Adipala, A. Bua, R. Edema

Journal of Experimental Agriculture International, Page 111-132
DOI: 10.9734/AJEA/2012/736

Cassava mosaic disease (CMD) resistant varieties have been used to manage CMD in Uganda. In spite the availability of a number of CMD resistant cultivars, several local landraces are continually grown in Uganda because they possess certain desirable traits, which may not have been fully met by the resistant varieties. Field based trials were setup to evaluate the response to CMD of some landraces that became prominent after the 1990s CMD pandemic. Experiments were located in areas where CMD is reported to have subsided namely, Mukono (Central Uganda) and Bulindi (Western Uganda). Three landraces were evaluated per site along with resistant (Nase 4) and susceptible (Bao) standards. Plots were planted with materials obtained from either diseased or healthy fields. The results showed differences in sensitivity to CMD among varieties tested, with landraces consistently having higher CMD incidences than Nase 4. The landraces tested in Mukono were more susceptible to CMD than even the Bao, while at Bulindi on the other hand, only Sibampale proved to be more resistant than Bao. There were differences in the whitefly populations among the cassava varieties and locations. High whitefly populations characterized all landraces and Nase 4. In most tested varieties, there was a higher infestation of whiteflies on healthy than diseased plants. Low spread of CMD among local landraces was observed in Bulindi as would be expected in areas where CMD has almost subsided (low pressure areas). However, in Mukono, disease spread among landraces was very rapid and high CMD incidences reaching 100% were recorded regardless of whether plots were planted with healthy or diseased cuttings suggesting it to be a CMD hot-spot. Thus, the use of clean planting materials as an effective phytosanitary method can only be employed under low disease pressure while high disease pressure areas need use of resistant varieties.

Open Access Review Article

Research on Mushroom as a Potential Source of Nutraceuticals: A Review on Indian Perspective

Selima Khatun, Aminul Islam, Ugur Cakilcioglu, Narayan C. Chatterjee

Journal of Experimental Agriculture International, Page 47-73
DOI: 10.9734/AJEA/2012/492

Mushrooms are highly nutritive, low-calorie food with good quality proteins, vitamins and minerals. Mushrooms are an important natural source of foods and medicines. Traditional aboriginals knew the medicinal importance of edible and wild mushrooms and these are now being screened for their bioactivity in various ailments. Mushroom represents a major and untapped source of potent new pharmaceutical products. A wide range of activities including antitumour, cardiovascular and antimicrobial are reported in mushrooms. In developing countries like India mushroom progress is a boon in the field of food, medicine, and in generating employment. The alternative systems of medicine utilize the curative properties of mushrooms. By virtue of having high fibre, low fat and low starch, edible mushrooms have been considered to be ideal food for obese persons and for diabetics to prevent hyperglycaemia. They are also known to possess promising antioxidative, cardiovascular, hypercholesterolemia, antimicrobial, hepato-protective and anticancer effects. The present review aimed to discuss on mushroom cultivation as well as medicinal importance as nutraceuticals, antioxidatives, cardiovascular, hypercholesterolemia, antimicrobial, hepato-protective, anticancer, clinical trials and availability of mushroom medicines from Indian context.