Volume 46 (2013): Issue 1 (March 2013)

Nitrogen uptake and free amino acid accumulation was evaluated in two South American cultivars of Lotus corniculatus L. differing in their tolerance to Al stress. The uptake of nitrate was affected by 1 mM Al more in the sensitive cultivar INIA Draco than in a relatively tolerant UFRGS (the uptake rate was 39.1% and 52.9%, respectively, of the control value at pH=5.5), whereas the opposite was true for the uptake of ammonia (60.1% and 50.1%). Treatment with Al also decreased the free amino-acid level to similar extent in both cultivars, mostly due to the significantly decreased level of asparagine (p = 0.003 and 0.026, respectively), the dominant amino-acid in Lotus roots. On the other hand, accumulation of stress metabolite - proline was achieved that was up to 5 time higher than in control. No considerable differences in this accumulation in INIA Draco and in UFRGS were found, so it is rather unlikely that proline content could contribute to the differences in Al-tolerance between the cultivars.

This article discusses the energy balance of the hemp biomass from the autumn and spring harvest which was used for the production of briquettes. The hemp plant (Cannabis sativa L.) used in this work is the variety Bialobrzeskie that was harvested on a trial plot in Prague-Suchdol in 2009 - 2010. Moisture content (MC), gross calorific value (GCV) and other technical parameters were evaluated for samples from the harvest of both periods. The autumn harvest results led to the assumption that the gross energy yield of the culture per superficies was 186.3 GJ ha-1. As compared to the previous results the spring harvest gave a gross energetic output of 161.4 GJ ha-1. The autumn harvest required more energy inputs compared to the spring harvest with values of 22.2 GJ ha-1 and 16.9 GJ ha-1 respectively. The most energy-consuming aspects of the biomass production were fuels (autumn) and the energy linked to the chemicals used (spring). Regardless of the higher net energy yield in autumn it was found that a spring harvest should be preferred because of its Energy Return on Energy Invested (EROEI) is 8.6. This is higher than for the autumn harvest (7.4).

Financial Fragility and Macroeconomic shocks make poultry agribusiness vulnerable to risk (unsteady profit). This tends to dampen investment drive and inhabits aggregate growth in the poultry sub-sector in Nigeria. To address this problem, time series data of 6 years (2004-2009) were collected from 200 randomly selected poultry farms. Multiple regression and t-test were used to analyse the collected data. T-test of return on investment shows that poultry agribusiness has low financial fragility and could be resilient enough to withstand macro-economic shocks. Co-integration results indicate that poultry agribusiness risks moves together with inflation rate, interest rates and real exchange rate. According to the results of vector autoregressive (VAR) test, it is shown that poultry agri-business risk is sensitive to macroeconomic shocks. But with sound financial structure, poultry agribusiness will be able to withstand financial fragility. The impacts-response analysis shows that increase in macroeconomic distortions leads to increase in poultry agribusiness risk in Nigeria. The results of study provided information on how macro economic shocks and fragile financial structure can trigger risk in poultry agribusiness sector. This information is very crucial to effective policy making and economic planning that will bring development to the poultry sector and the Nigerian economy. Factor analysis confirmed that inflation rate (0.0039) and interest rates (0.1218) are the significant distortion factors (P < 0.01) that exert more impact on poultry agribusiness risk. Regulated interest and inflation rates would stabilize earnings and lead to growth in poultry agribusiness in Nigeria.

The study examined the determinants of the perceived effectiveness of an organic fertilizer used by farmers in Oyo state, Nigeria. A stratified and purposive sampling technique was used to select 110 respondents from three major vegetation zones of the study area. Descriptive statistics were used to present the findings of the study while the Chi-square analysis was used to test the study hypotheses. Data revealed that 77.3% were aware of the organic fertilizer while only 60.0% of those aware made use of the fertilizer. Among the users, 37.3% applied 25 g of the organic fertilizer per crop stand which was largely on maize (92.16%). Average rate of application was 0.40 tons per hectare. Application method was mainly through side dressing (58.82%) and ‘dig and cover’ (29.41%). Time of application varied from the time of sowing to 4 weeks after planting with the majority of farmers (64.71%) applying at 2 weeks after planting. Interest in the continuous use of the fertilizer was high (62.75%) and the majority of users (52.95%) perceived that the organic fertilizer was effective. Chi-square analysis revealed that the rate and method of application were significantly related to the effectiveness of the fertilizer (χ2 = 15.66, P < 0.05 and χ2 = 8.79, P < 0.05, respectively). Rate and method of application are thus significant determinants to fertilizer effectiveness. Extension activity should therefore focus on farmer education to ensure proper use of the organic fertilizer for maximum productivity

Heart rate (HR) is related to the physiological state of most of vertebrates, e.g. the level of metabolism, motion or stress. In previous reports, the HR of eland was measured during sedation and general anaesthesia. Therefore, we wanted to evaluate HR in alert eland with emphasis on variations by different behaviours and time of the day. We measured HR by Polar S610 device in an adult male and an adult female. Behaviour during recumbent and rumination, standing and rumination, standing, standing and eating, movement, excitement during feeding, stressful event, handling in restraint box and sleep were recorded and synchronised with data from HR device. In the male, HR was lowest during recumbency and rumination. In the female, HR was lowest during sleep. The highest HR was measured during handling in a restraint box. The HR was higher during the night for most of the behaviours. Further research should focus on explaining the diurnal variation in HR as it relates to specific behaviour.