Germination of Kalanchoé blossfeldiana seeds is absolutely light‐requiring and needs repeated daily light periods. With increasing length of the photoperiod there was a gradual escape from the far‐red inhibition. This escape depended also upon the duration of the far‐red exposure: 10‐second far‐red caused a strong inhibition after a 10‐ to 30‐minute photoperiod and did not inhibit after a 4‐hour day, although the effect of the latter was completely suppressed by 5 minutes far‐red. The action of a 12‐hour photoperiod was not reversed by 10 minutes far‐red but it was by 12 hours far‐red. Light intensity and temperature during the photoperiod were two other important factors influencing the escape from far‐red inhibition. The common features of this escape displayed in very different photomorphological responses are stressed. In order to explain our results in terms of phytochrome action, we distinguish two effects of white light: 1) on the initial photoconversion of the inactive to the active PFR form 2) on the much slower transformation of PFR to a reacted form P*FR; the latter reaction can also proceed in darkness, but is enhanced by light and is dependent upon light intensity and temperature; this reacted phytochrome is not reversible by a brief far‐red illumination.

The effects of irradiations with different proportions of red/farred light and of gibberellic acid on the phytochrome‐mediated seed germination of Kalanchoë blossfeldiana cv. Feuerblüte, were studied.The seed coat transmits much more red than far‐red light, and therefore the energy ratio between 660 nm and 730 nm is given only for the transmitted light. Decreasing this ratio from 65 to 1.0 caused only a very slight inhibition. If this ratio is further lowered to 0.64, a 10 min terminal irradiation after a 3‐h white light photoperiod is inhibitory, but a 12‐h photoperiod or continuous irradiation is not. If the ratio is decreased to 0.44 or 0.31, a 12‐h photoperiod is now also inhibitory, although continuous irradiation and 10 min terminal irradiation are still more inhibitory. These results are discussed in terms of phytochrome phototransformations.Although gibberellic acid is unable to cause any germination in complete darkness, it can result in a very high germination percentage, if combined with treatments which by themselves do not induce any germination such as continuous far‐red, terminal far‐red after short photoperiods, or very short photoperiods at 25°C. These results point to a strong synergism between gibberellic acid and the so‐called stabilized form of phytochrome, P*FR.

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The Belgian steel industry falls apart into four groups. The Flemish industry consists mainly of a very modern steel plant Sidmar near the port of Ghent controlled by the industrial holding Arbed. The Walloon industry falls apart into three basins : Cockerill in Liège; the holy triangleof Charleroi, controlled by Frère-Bourgeois, Cobepa (Paribas) and Bruxelles-Lambert (this three holdings being associated in the Financière du Ruau) ; the independents.In the Walloon industry the successive processes of steel making are distributed over a great number of plants, most of the equipment is outdated, labour relations are bad and so is management.The finances required to renew this ancient industry are so large that the holdings cannot do so without the aid of the Belgian Government and the European Communities.Beginning of 1977, Davignon (CEE), proposes to freeze the production and market shares of the member countries, and to increase the European steel price by EEC tariff measures, in this way protecting the low productivity concerns ; not in the least the walloon concerns.  The European Communities promise financial help for restructuring.The implicit condition is comparative advantage of enterprises. In the Belgian context, this would mean that Sidmar would be extended and part of the Walloon industry closed down. The next move of the Brussels-Walloon concerns is, therefore, to corner Sidmar.During the course of 1977 and the first half of 1978 the Government negotiates with employers and unions a restructuring plan and general steel agreement, the «Plan Claes». The plan foresees in a lasting ceiling imposed on Sidmar; in a very large fiow of restructuring aid,mainly from public funds and the set-up of an intricate network of semi-governmental institutions.The Plan Claes is a purely political compromise. From the economic point of view, the plan wilt only speed up the definite emigration of traditional steel making processes towards the semi-industrialized countries.