Oilseed rape yield

Winter barley is an ideal entry for oilseed rape because the earlier harvest allows early drilling of rape. It has been shown on organic farms that building up fertility by using a green manure crop, such as red clover, has paid off financially, with the subsequent boost in yield of the following cereal crop. 

According to FAO statistics, the average field harvest of oilseed rape in Europe is 2500 kg ha-1 [8] and based on our own experiments, 3000 kg ha-1 yields can be obtained in the greenhouse. This translates into an annual harvest potential of 9000 kg ha-1, based on the fact that three harvests each of 3000 kg ha 1can be obtained in a year. The desired protein is produced predominantly in the sprout. The developing seeds do not accumulate recombinant protein. 

Oilcrops Oilseed rape, safflower, Camelina sativa Oil-body purification, sprouting system Lower biomass yields, oil bodies incompatible with glycosylation... 

Notably, however, any comparison of biodiesel vs. bioethanol should be done with great caution, because analysis of an industry such as that related to biofuels is a very complex task and all conclusions are country dependent. It may be interesting, however, to compare the energy balance and environmental impact in producing biodiesel from oilseed rape and bioethanol from wheat crops [4], Table 9.3 reports this comparison. The energy balance for bioethanol is more positive than for biodiesel, in particular when straw is utilized, mainly due to the higher yield... 

Forcella, F. (1987). Herbicide-resistant crops Yield penalties and weed thresholds for oilseed rape (Brassica napus L.). Weed Res., 27 31-34. 

Jay, C.N., Rossall, S., Smith, H.G. Effects of beet western yellows virus on growth and yield of oilseed rape (Brassica napus). J Agri Sci 1999 133 131-139. 

The tropical oil crops, coconut and palm, are the most efficient oil-producing crops, with coconut plantations yielding up to 2 tonnes per hectare of oil and the best performing palm plantations from 5-6 tonnes per hectare. By comparison, oil yields of temperate oil crops are typically of the order of 1-2 tonnes per hectare for the best oil-yielding crops (oilseed rape and sunflower). Clearly, Table 2.1 represents only a small fraction of oil-bearing plant species. Many other seed, fruit and nut oils are extracted for food use, however unless they contain fatty acid profiles or fatty acid derivatives of specific industrial interest, total oil-yield, fatty acid yield and cost of the final oil product tends to limit their use in industrial applications on all but a small or localised scale. 

A second approach, when a diverse gene pool is available, is to interbreed species with appropriate traits by standard seed-breeding processes. This has been done very effectively with species of brassica to yield the modem oilseed rape (canola). If necessary, the gene pool can be extended by mutation resulting from chemical treatment or from irradiation. This may produce novel varieties with interesting traits and is the basis of the low-linolenic lines from linseed, and other examples are described in Section 9.3. 

Rucker, B. and Robbelen, G. (1996) Impact of low linolenic acid content on seed yield of winter oilseed rape (Brassica napus L.). Plant Breeding 115 (in press). 

As calcareous soils can be found at fairly high altitudes and the fields are often exposed, great care should be taken when growing crops which shed their seed easily, e.g. oilseed rape. Harvesting must be carried out carefully to minimise yield loss. 

Oilseed rape has received most attention regarding l bridisation in recent years. In 2012 about half of the NIAB recommended and provisionally recoimnended varieties were hybrids and many showed yield advantages or other desirable traits compared with conventional varieties. These restored hybrids are FI hybrids produced in a variety of ways, usually from crossing inbred lines but sometimes from more complex breeding operations involving open pollinated varieties. 

The harvest index of wheat has been substantially increased by the breeding of semi-dwarf varieties, and a closely related trait, improved resistance to lodging, has resulted in improvements both to yield and crop quality. Improved yields have been an important trait in all of the other major crops. In some cases improvements have been obtained by plant breeders selecting for winter hardy types which can be autumn sown. Oilseed rape is an important example, others, less successful, have included linseed, peas and lupins. 

The disease Sclerotinia sclerotiorum is important in oilseed rape and a number of other crops as well. It infects the stems of crops during flowering and has a substantial effect on yields. During combining, fragments of the sclerotia of this fungus often break away from infected stems and become mixed in with the harvested seed. There are no field standards for the incidence of this disease but the permissible number of sclerotia in a lOOg certified seed sample is 10 (5 in a 70 g sample for turnip rape varieties). 

The recommendations for oilseed rape in the Fertiliser Manual (RB209) are based on yields of 3.5 t/ha of winter OSR and 2 t/ha of spring OSR. To return those nutrients removed from the soil 14 kg of and 11.0 kg of K O should be applied for each toime of seed/ha expected over and above these yields. This only need apply when indices are below the target index of 2 for each element. 

Winter oilseed rape has ayield range of 2-5t/ha with 3.5t/habeing average. For spring oilseed rape the yield range is 1-3 t/ha with 2 t/ha being average. 

There are no special agronomic requirements of these crops grown for biofuels. Any oilseed rape variety can be used for biodiesel and wheat is the favoured cereal for bioethanol as its starch yield is higher than barley. British Sugar have a bioethanol plant at their Wissington factory which can also use wheat. 

Peas do not compete well with weeds and efficient weed control is essential to avoid yield loss. Pereimial weeds should be dealt with before planting and thistles, oilseed rape and groundkeeper potatoes can be a particular problem. Nettles and thistles can interfere with hand picking and, in machine-harvested crops, weeds can lead to crop rejection from the processor. Inter-row cultivations may be effective when the peas are between the second and fifth node growth stage. 

Knight S, Knightley S, Bingham I, Hoad S, Lang B et ai, HGCA Project Report 502, Desk study to evaluate contributory causes of the current yield plateau in wheat and oilseed rape,HGCA20 2. 

Additional stndies have been conducted on the extraction of triglycerides and free fatty acids nsing SC-CO2 alone. Typically, an inCTease in pressure increases oil extraction yield and operating pressure has the greatest impact on oil yield. This is confounded by tanperature. An increase in extraction tanperature increases the oil extraaion yield at high pressure. With lower pressure, an increase in extraction tanperature lowers the oil extraction yield (Dunford and TemeUi, 1997 Fattori et al., 1988). Table 8.1 summarizes selected SC-CO2 operating parameters for extraction/ fractionation of oil and components from canola and oilseed rape. 

Interactions between SC-CO2 operating pressure and temperature on oil extraction efficiency of oilseed rape have been further modelled (Boutin et al., 2011). Increasing the extraction pressure from 30 to 34 MPa increased the oil extraction efficiency, especially at 20 min extraction time. Increasing the tanperature from 50°C to 70°C decreased the extraction efficiency due in part to a decrease in CO2 density. The authors concluded that small variations in tanperature and pressure could lead to significant differences in extracted oil yield especially during the initial phase of the extraction. 

A theoretical extraction of oil and components from canola and oilseed rape, press cake/meal and/or deodizer distillate is illustrated in Figure 8.1. Manipulation of SC-CO2 operating parameters, including cosolvent choice and concentration, results in sequential or differential fractionation of these components and relative yields as described earlier and explored in the following sections using other plants as starting material for reference. 

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