RAPE POLLEN ALLERGY
In 1948 Juhlin-Dannfelt published his investigation of the occurrence of different types of pollen allergy in Sweden. According to Urbach (1937) and Hansen (1940), certain regions of Europe have only one pollen season. Juhlin-Dannfelt showed that there are two pollen seasons in Sweden, one in spring in which catkin bearing trees play an important role, and the other in June and July, months in which the grass pollens predominate. Juhlin-Dannfelt also reported hypersensitivity to other types of pollen, especially from some Compositae, particularly the oxeye daisy. He also described isolated instances of allergy to pollen from the genera of Taraxacum, Rumex, Plantago and Chenopodium. Recently a man presented himself at the department of allergy complaining of asthma and pollinosis, which on investigation proved to be due to hypersensitivity to rape pollen. As a search of the literature failed to reveal any reports of hypersensitivity to pollen from plants belonging to the Cruciferae family, a brief description of the case observed was considered justified.
Oilseed rape sensitivity
OSR is a widespread atid ancient crop with evidence of cultivation in India (from 20(X) BC), and in China and Japan [1]. In Europe, oilseed rape and other Brassica seed crops have been cultivated since at least the 15th century [2], originally for the production of lamp oil. These crops were mainly cultivated in Northern latitudes where the climate would not support the growth of olives and sunflowers, the main sources of oil at that time. The word 'rape', as applied to these oilseed plants, is from the Latin rapum meaning tumip. Since the second world war, when edible oils were at a premium, there has been a policy to encourage home production of OSR because the oil contains a good nutritional balance, and since 1973 this crop has been subject to EEC/EU subsidy. The crop has increased in economic value and is now the most important oilseed crop in Western Europe, with about 6-10% of arable land in the UK given over to its cultivation. Two crops can be harvested in one season. One species, Brassica napus comprises about 95% of the crop and has two forms. One is sown in autumn, overwinters and characteristically flowers yellow in spring and the other is sown in spring and flowers in late summer. The small remaining proportion is B. campestris which is also spring sown. There are many varieties of these species which have been bred for speciflc characteristics, for example to eliminate toxic glucosinolates. The seeds are harvested and crushed to release oils which are used in the production of margarine, cooking oil and in food blending. The oils can be converted to a methylester which is an efficient diesel substitute. Some of the oils with long chain fatty acids, erucic acid (C22:1, cis-13) have suitable viscosity and are robust enough to use as machine oil, and as a base oil in the plastics industry, for example in the manufacture of cling-film. These oils have a great advantage over traditional oils in that they are readily biodegradable. After the oil has been extracted there is a high-protein seed meal residue which has increasing value as a vegetable source of animal feed. In addition, OSR is an excellent break crop, i.e. its use in crop rotation results in soil improvements. A more recent use of the OSR crop is for biotechnology, for example in the pharmaceutical industry OSR is used as a vehicle for recombinant hirudin (blood clotting factor) production. This crop is clearly of great economic importance and any associated public health concem should be investigated seriously.
Inhibition of Root Growth and Polyamine Metabolism in Sunflower (Helianthus annuus) Seedlings Under Cadmium and Copper Stress
Although sunflower is usually regarded as a highly tolerant crop, impairment of root growth at initial stages of plant development may result in poor crop establishment and higher susceptibility to pathogen attack. In order to evaluate if Cd2+ and Cu2+ may impact on sunflower germination and initial root development, a pot experiment under controlled conditions was carried out. Possible involvement of polyamine metabolism in sunflower response to these stressors was also investigated. Although Cd2+ and Cu2+ treatments affect neither seed germination nor radicle emergence, sunflower seedlings grown in the presence of these heavy metals showed significant inhibition of root growth, being this inhibition greater for Cd2+. Both metals caused significant increases in proline contents at the highest concentrations tested (0.5 and 1 mM), and these increments were more pronounced for Cd2+ treatments, especially between days 3 and 10. Metals also increased putrescine (Put) contents at all concentrations assayed from the seventh day onward, causing no variations on this polyamine time-course pattern. Spermine and spermidine contents, however, were increased only by 1 mM Cd2+. Arginine decarboxylase seems to have been the enzyme responsible for Put increases under both metal treatments. This work demonstrates that initial root growth of sunflower seedlings may be significantly impaired in Cd2+ or Cu2+ contaminated soils. It also shows that polyamines are key biological compounds, which are probably involved in signaling pathways triggered under stress environmental conditions.