Oilseeds winter rape

These are detailed in the HGCAMK Recommended Lists for Oilseeds. The winter rape lists are regionalised between North and EastAVest... 

The fact that is not radioactive means that it can be used safely in experiments in the field, but it also means that much patient work is needed to obtain results. The approach is demanding in terms of time, equipment, and skilled manpower, but it has made a great contribution to the understanding of the nitrate problem. The results that are outlined here are from experiments made by staff at Rothamsted, but key contributions have also come from Scotland and France. " The majority of the Rothamsted experiments involved winter wheat, but oilseed rape, potatoes, beans, and sugar beet were also grown. The soil is a factor in nitrate leaching, and three types were used, the flinty, silty clay loam at Rothamsted, a sandy loam at Woburn in Bedfordshire and a heavy sandy clay at Saxmimdham in Suffolk. 

Up to Harvest. Oilseed rape and field beans are used as break crops for winter wheat on a variety of soils, and potatoes are used on the lighter soils. Sugar beet may also be grown, but this depends not only on the soil but also on the proximity of a sugar beet processing factor. Four Rothamsted-based experiments compared the effectiveness of winter wheat and winter oilseed rape in their use of labelled nitrogen fertilizer. Potatoes were included in two of these experiments and sugar beet and field beans in one experiment each. Two criteria based on the... 

Table 2 Efficiency of use of nitrogen fertilizer by winter wheat, winter oilseed rape, potatoes and sugar beet.

Data of a different kind, the nitrate losses through the held drains of the Brimstone experiment,also suggest that winter oilseed rape uses nitrogen fertilizer somewhat less efficiently than does winter wheat, but this experiment did not include the other crops discussed above. 

After Flarvest. How do the memory effects shown by the other crops compare with those of winter wheat Winter wheat did not show a memory effect after one year, but oilseed rape does seem to do so. Researchers of the Agricultural Development and Advisory Service found that nitrate production by microbes in the soil after a rape crop increased with the amount of fertilizer given to the crop (R. Sylvester-Bradley, personal communication). One reason may lie in this crop s habit of shedding its leaves as harvest approaches, which means that the microbes in the soil get early access to these residues. This habit might contribute to the apparently smaller efficiency of this crop in using nitrogen fertilizer. The crop may be just as efficient as winter wheat at taking up the fertilizer but drops... 

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. 

Metazachlor is a selective preemergence herbicide active on a wide range of both broad-leaved and grass weeds. It can be used selectively in Brassica spp. crops including winter oilseed rape at a rate of 1-1.8 kg active ingredient/ha. 

Franen, M., and W. Paulmann. 1999. Breeding of hybrids varieties of winter oilseed rape based on the MSL-system. Tenth International Rapeseed Congress, Canberra, Australia, pp. 258-263. 

Pierre, J., Mesquida, J., Marilleau, R., Pham-Del6gue, M.H. and Renard, M. (1996). Nectar secretion in winter oilseed rape (Brassica napus) Quantitative and qualitative variability among 71 genotypes. Plant Breed. 115, 471 76. 

Improved resistance to low temperatures has also been found, for instance, in cucumber and zucchini squash treated with paclobutrazol [48], in oats and rice under the influence of tetcyclacis [1,8] and in winter oilseed rape that had been treated with BAS 111. . W [32]. Similarly, plants performed better under conditions of drought after they had been treated with compounds such as triadimefon, flurprimidol, paclobutrazol, uniconazole and tetcyclacis [3, 16, 42, 47]. 

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). 

Barsby, T.L., Yarrow, S.A., Kemble, R.J. and Grant, I. (1987) The transfer of cytoplasmic male sterility to winter-type oilseed rape (Brassica napus L.) by protoplast fusion. Plant Sci. 53, 243-248. 

Cleavers (Fig. 5.13a) is the most competitive weed in winter cereals and winter oilseed rape, more competitive than wild oats. It can be confused at the seedhng stage with ivy-leaved speedwell (Fig. 5.13a). Note that cleavers has a notched cotyledon and the cotyledons are not stalked. Cleavers germinates at fairly low temperatures mainly in the autumn and winter, with some in the spring. 

Destroy remains of harvested over wintered brassica crops by beginning of May. Several insecticides approved for use in oilseed rape. Some EAMU recoimnendations in other brassica crops. 

A very serious pest of brassicas. Winter oilseed rape can be attacked by the third generation of flies. A weather based forecasting system is available. 

Not all brassicas affected. Several weeds are hosts to this aphid. Populations vary widely each year due to weather conditions. Threshold for treating winter oilseed rape is 13% plants infected before petal fall. 

Year 1 - oilseed rape Year 2 - first wheat Year 3 - winter beans Year 4 - first wheat Year 5 - peas Year 6 - first wheat Year 7 - winter barley... 

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 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. 

Slugs may be a serious problem of winter oilseed rape, particularly in trashy or cloddy seedbeds or when late established. Metaldehyde or equivalent should be applied where there is a high risk, and method of establishment may influence the timing of this application. The peach-potato aphid may need a pyrethroid or pirimicarb spray in October/November, but populations of the aphid are highly resistant to both. 

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. 

Winter wheat chiefly attacked. Often worse after oilseed rape. Use slug traps to check likely risk with a bait such as chicken layers mash (not slug pellets). A catch of 4 slugs/trap suggests a high risk of damage. 

Petersson, A., Thomsen, M.H., Nielsen, H.H., Thomsen, A.B., 2007. Potential bioethanol and biogas production using HgnoceUulosic biomass from winter rye, oilseed rape and faba bean. Biomass Bioenergy 3,812-819. 

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