A quasi-continuous automatic recording system of apparent electrical conductivity data of soil (ECâ‚) was assembled to obtain at a reliable and fast rate, spatial distribution maps of this physical parameter. The device was moved manually throughout several profiles in a small zone of 3753 m2 used for the farming of otoes (Xanthosoma sp.) in Panama, Central America, obtaining 401 voltage values in approximately 20 minutes. These voltages were turned into ECâ‚ values and mapped. This result was compared with total dissolved solids (TDS) and pH maps of 29 soil samples at 20 cm of depth; salinity was also measured. The ECâ‚ map presented a zone of high electrical conductivity (130 - 500 μS/cm) on the Eastern part which is consistent with the zones in the TDS and pH maps whose value ranges fall within the optimal threshold for Xanthosoma sp. (45-95 mg/l and 5.5-5.8 respectively). Salinity levels were weak (<0.10%) and are consistent with the zone of high ECâ‚ typical of non-saline soils. All these results show a significant potential in the use of this mobile system to achieve a fast assessment of agricultural exploitation zones. Finally, a highly moderate correlation is showed among the values of ECâ‚ and TDS, and pH data.
In the present study, the influence of soil properties on pre-emergence herbicide effectiveness was estimated in bioassays. Dose-response experiments were carried out to estimate the relationship between soil organic matter content and herbicide efficacy. Two weed species (Alopecurus myosuroides and Stellaria media) and two herbicides (pendimethalin, chlorotoluron) were included in the experiments. In bioassay trials on soil with varying organic matter content, dose-response curves were estimated for pendimethalin and chlorotoluron. Effective dose (ED50) values were calculated. The experiments were conducted in a climate chamber under defined conditions. The results demonstrate that the efficacy of soil-applied herbicides is related to the soil organic matter content within agricultural fields. Therefore precise usage with variable herbicide application rates can be part of a precision farming concept. A reduction in herbicide is possible.
The growth performance of Clarias gariepinus Burchell, 1822 fed Gliricidia sepium leaf meal and supplement with enzymes (Roxazyme®) and Maxigrain® were examined. The fingerlings having weight of about 6.34±0.43 g were stocked in12 plastic aquaria with 50 liters capacity at the rate of 25 juvenile per aquarium and fed on four different dietary treatments for 42 days. The experimental diets varied with increasing levels of G. sepium leaf meal, 0%, 10% without enzyme supplementation, 10% supplemented with enzyme (Roxazyme G2), and 10% supplemented with enzyme (Maxigrain). The growth performance, Feed Conversion Ratio (FCE) and water quality were evaluated during and by the end of trial. The results showed that all experimental treatments promoted positive growth and no mortality was encountered during the experimental period. However, theFinal Body Weight (FBW) of C. gariepinus was found to differ significantly among fed experimental treatments. C. gariepinus fed with T4 had the highest significant (P< 0.05) FBW (14.15 g), followed by T3 (12.58 g) and T1 (12.10 g) whereas least FBW was recorded in C. gariepinus fed T2 (10.49 g). C. gariepinus fed with T4 had higher WG which was found to be significantly different from other treatments while no significant difference (P> 0.05) in WG was found amongT1 and T3 and the least WG was recorded in C. gariepinus fed T2. C. gariepinus fed T2 had the highest significant (P<0.05) value of FCR followed by T1 and T3 while the least significant (P<0.05) value FCR was recorded in C. gariepinus fed T4. Mean temperature, pH and dissolved oxygen (DO) ranges from 26.1°C to 28.10C, 6.89 to 8.13 and 1.9 mg/l to 8.13 respectively while the ammonia value varied from 0.21 mg/l to 0.67 mg/l. Therefore, it can be concluded that G. sepium can be used up to 10% supplement with enzyme in the diets of C. gariepinus at fingerlings stage with good performance with better quality of water.
A field study was conducted during rainy (kharif) season of 2013 to find out the effect of bioinorganic nutrient combinations on yield, quality and economics of mungbean [Vigna radiate (L.) Wilczek]. The twelve treatments comprised one control, three levels of inorganic sources (75, 50 and 100% NPK of recommended dose) and other eight in combination viz. 50% RDF+ Rhizobium + Phosphorus solublizing bacteria (PSB), 50% RDF + 2.5 t/ha Vermicompost, 50% RDF+2.5 t/ha Vermicompost/ha + Rhizobium + PSB, 75% RDF+ Rhizobium + PSB, 75% RDF + 2.5 t/ha Vermicompost, 75% RDF + 2.5 t/ha Vermicompost + Rhizobium +PSB, 100%RDF+ Rhizobium+ PSB and 100% RDF + 2.5 t/ha Vermicompost were laid out in randomized block design with three replications. Amongst combinations, significant improvement in plant height at harvest, yield attributes, yield, protein per cent, nutrient content and uptake were recorded with application of nutrients through 75% RDF + 2.5 t/ha vermicompost + Rhizobium + PSB as compared to other combinations, followed by treatments 100% RDF + 2.5 t/ha vermicompost and 100% RDF + Rhizobium + PSB. The highest and comparable net returns were obtained with the application of 100% RDF + Rhizobium + PSB (INR 52894.73) followed by 75% RDF + 2.5 t/ha vermicompost + Rhizobium + PSB (INR 51582.60) and 75% RDF + + Rhizobium + PSB (INR 50664.74). The above studies show that bioinorganic combinations have their own roles play to higher productivity, not only solely supply all the nutrients to the soils but also create favorable conditions for betters growth to producing crop.
Chickpea is an important legume crop in Amhara region. The harvested grain of the crop could be stored for more than six months to look for better price and/or as insurance for food security. In the store Callosobruchus chinensis (L.) cause considerable damage to the grain. Noug oil and lemon oil at 4 ml/kg, powder form of neem seed and leaves, pepper seed and leaves, hag enea leaves, endod seed, eucalyptus leaves and Persian lilac seed and leaves at 4% w/w were evaluated for their efficacy against C. chinensis. Primiphos-methyl at the rate of 0.5 gm/kg was used as a standard check. Noug oil was the most effective botanical and statistically at par with primiphos-methyl in inducing adult mortality, reducing initial number of eggs laid on grains, number of holed grains, adult progeny emergence and weight loss. Among other treatments, lemon oil, neem seed and pepper leaves were promising. Botanicals afforded the protection of 59.2% to 99.2% over the untreated check. Noug oil and eucalyptus significantly delayed the developmental period of C. chinensis from 4.67 to10.3 days. The germination of grains treated with botanical was significantly higher than grains from the untreated check. Thus, botanicals proved promising and effective for the control of C. chinensis and can be used as a component of IPM.
The aim of this work was to assess heavy metal concentrations of samples collected from areas around a volcanic mountain in Tanzania. Fifty five soil samples and 10 samples of bean leaves were analysed using Energy Dispersive X- ray Fluorescence spectrometry (EDXRF). The concentrations of heavy metals in the samples are presented, statistical analysed and compared with control. The concentration in bean leaves are also compared with the maximum tolerable limits set by FAO/WHO to assess their safety for consumption. The results from this study show that high concentration of elements in both soils and bean leaves samples from Oldoinyo Lengai areas might be associated with frequently eruptions of the volcanic mountain of Oldoinyo Lengai. Hence, farming in Oldoinyo Lengai areas is introducing heavy metals in the food chain.
This study examines the socioeconomic factors that influence farmers’ willingness to accept monetary compensation to engage in tree planting and to evaluate realistic payment of incentives. Contingent Valuation method was employed to elicit bids levels of 200 farm households in Ghana. The empirical results of a Generalized Linear Model reveal that age of the household head, household size, education, perception to climate change, distance to the farmland, farm size, off-farm work and quantity of maize sold annually significantly influenced households’ decision to accept compensation to engage in tree planting activities. These results have implications for forest management in developing countries.