http://hdl.handle.net/11019/964 End-of-Project Reports from CELUP Programme Tue, 07 Nov 2017 00:36:52 GMT 2017-11-07T00:36:52Z http://hdl.handle.net/11019/1520 Title: Evaluation of the Effect of Tocopherols on the Stability of Biodiesel Authors: Fröhlich, A. Abstract: A comprehensive study was carried out on the effects of naturally occurring tocopherols and carotenoids on the stability of biodiesel-grade methyl esters. Commercially available tocopherols and carotenoids, α-, γ- and δ-tocopherol, carotene and asthaxanthin, were added to destabilised methyl esters and the solutions were exposed to air at 65oC. The stabilising effect of the added tocopherols and carotenoids was determined from the number of days needed to reach the same increase of viscosity as destabilised methyl ester without tocopherols after 1 day. All three tocopherols stabilised methyl esters; γ- being the most effective and α- the least. The stabilising effect of tocopherols increased with concentration up to an optimum level. Concentrations above this level did not improve stability significantly. The stabilising effect of the tocopherols also depended on the composition of the methyl ester; they were most effective in tallow methyl ester, and had the least effect on sunflower methyl ester. Carotene and asthaxanthin had no effect on the stability of the methyl esters. However an unidentified carotenoid in rape methyl ester changed the oxidation pattern by reducing rates of peroxide and viscosity increase, without affecting overall stability. Description: End of Project Report Fri, 01 Apr 2005 00:00:00 GMT http://hdl.handle.net/11019/1520 2005-04-01T00:00:00Z http://hdl.handle.net/11019/1509 Title: Improving the Yield and Quality of Arable Crops in Organic Production Systems Authors: Crowley, J.G. Abstract: Ireland's ability to supply organic arable products to meet future market requirements depends on the provision of scientific quantitative information on the production of these crops. The conversion of an 8-ha site at Oak Park is described. The establishment of a single stockless 7-year rotation (wheat, potatoes, oats, legume, spring barley followed by two years’ grass/clover lea) with three replicates is described. The results of the first series of experiments are presented and the possible implications discussed. Description: End of Project Report Fri, 01 Apr 2005 00:00:00 GMT http://hdl.handle.net/11019/1509 2005-04-01T00:00:00Z http://hdl.handle.net/11019/1487 Title: Reduced Fungicide Inputs in Winter Wheat Authors: Dunne, B. Abstract: Nine trials were conducted over three years at three sites to evaluate the efficacy of reduced rates of various fungicide products for their biological efficacy in controlling stem, foliar and ear diseases of winter wheat as well as their effects on yield and grain quality, and to compare the relative profitability of full and reduced rates of fungicides. The results show that the use of half rates can give an economic benefit over that of full rates in many situations. In circumstances where variety or seasonal factors resulted in low to moderate foliar disease pressure the use of half rates gave similar yields to that of full rates. Where foliar disease pressure was high, half rates generally gave lower yields than full rates but the amount of the reduction varied with the fungicide product used. The use of spray additives improved the yield response of the half rate treatments in most cases. Disease levels (septoria) were higher in treatments where half rates were used, compared with the corresponding full rates, but the used of spray additives improved the disease control in the half rate treatments. The timing of spray applications is critical when half rates of fungicides are being used. Reduced rate treatments need to be applied more frequently. In these trials reduced rate treatments were applied as a three-spray programme rather than the conventional two-spray programme. Description: End of Project Report Tue, 01 Sep 1998 00:00:00 GMT http://hdl.handle.net/11019/1487 1998-09-01T00:00:00Z http://hdl.handle.net/11019/1486 Title: Reduced Herbicide Inputs in Cereals Authors: Mitchell, B.J. Abstract: The objective of this project was to examine if herbicides used in cereals at rates lower than recommended by the manufacturer (reduced rates) would give acceptable weed control resulting in lower crop production costs. Field trials with a number of herbicides at full and reduced rates were carried out in winter barley, winter wheat and spring barley in 1994-1996. Herbicides used at recommended rates gave the highest and most consistent levels of weed control. Herbicides used at 50% of the recommended rates gave slightly lower levels of weed control than the recommended rates but did not result in lower yields. While rates lower than 50% gave about 70% control of weeds, grain yield was reduced in some trials. Reduced rates gave higher weed control in barley than in wheat. The level of weed control was influenced by weed species and the growth stages of the weeds at the time of herbicide spraying. Thus selection of herbicides and their rates of application should be field specific. The findings show that it is possible to reduce the amount of herbicides used in cereals with considerable cost savings and reduced risk of herbicide residues in grain, soil and water. Description: End of Project Report Tue, 01 Sep 1998 00:00:00 GMT http://hdl.handle.net/11019/1486 1998-09-01T00:00:00Z