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Annual Brussels sprouts 总被引：2，自引：0，他引：2
Annual flowering in Brussels sprouts, originally found in one plant in 1953, is dominant over biennial flowering and the difference is monogenic. Deviations from expectations may be the effect of potentially annual plants which do not come to flower owing to a very late time of flowering.
Samenvatting In 1953 werd één spruitkoolplant gevonden, die in het jaar van uitzaaien bloeide. Op grond van de resultaten met F1's en F2's van kruisingen tussen éénjarig en tweejarig en terugkruisingen wordt geconcludeerd tot dominantie van éénjarigheid en tot een monogeen verschil. Afwijkingen van verwachtingen betreffen steeds een tekort aan éénjarigen en worden toegeschreven aan het niet tot bloei komen van potentiële éénjarigen door een zeer late bloeitijd, welke genetisch geïnduceerd wordt door de tweejarige ouder, die niet op vroege bloei in het eerste jaar kan worden geselecteerd.相似文献
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S.J. Wellensiek 《Scientia Horticulturae》1973,1(2):177-192
The influences of vernalization, photoperiods of 8, 12 or 16 hours, and gibberellic acid (GA) on the flower bud formation of the pea were studied in a Late, a Medium and an Early flowering genotype, each genotypically either Tall or Dwarf, but for the rest genetically identical. The detailed experimental results are summarized on p. 188 (Section 3.4).Just as Medium and Early, Late is considered as a quantitative long-day plant, but its necessary duration of exposure is exceedingly long under short-day conditions. It is suggested to replace ‘critical day length’ by ‘critical duration of exposure’ in the pea and similarly reacting plants. Flower bud formation becomes increasingly more difficult from Early to Medium to Late, from Tall to Dwarf, from photoperiods of 16 hours to 12 hours to 8 hours, and certain combinations become marginal.Vernalization and GA had dramatic effects under the same marginal conditions, but GA was sometimes effective, where vernalization was not. In case of effect of both factors, strong interactions were found: vernalization reduced the effect of GA, and the reverse. This suggests similarity of action.The implications of these results for the mechanism of flower bud formation were discussed. It is presumed that the triple allelic genes for Late, Medium and Early determine a strong, an intermediate and a weak inhibition of flower bud formation, respectively. Inducing factors remove these inhibitions. Long day induces so strongly that vernalization and GA have hardly any supplementary effects, but under decreasing photoperiods, or more general, under marginal conditions, vernalization and gibberellic acid become more and more important as inducing factors. 相似文献
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S. J. Wellensiek 《Euphytica》1959,8(2):125-130
In order to establish the effect of inbreeding in Cyclamen, one motherplant of Rose van Aalsmeer was used to produce successively five inbred generations, I1, I2, I3, I4, and I5. Similarly, one motherplant of Wit met oog fimbriata was used for the production of an I1, an I2 and an I3. By keeping the motherplants alive, plants could be obtained which, although belonging to different generations, were of the same age. Comparison of the numbers of flowers formed by these plants during their first flowering season showed a clear effect of inbreeding, especially in the I3, I4 and I5, consisting of a significant reduction of the mean number of flowers. When two inbred lines, either of one variety or belonging to the two different ones, were crossed, the F1 reached the level of the I1. In both cultivars there were rather large differences among individual lines, some showing a strong effect of inbreeding, while in others the effect was only slight or sometimes even absent.Publication 192, Laboratorium voor Tuinbouwplantenteelt, Landbouwhogeschool, Wageningen 相似文献
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S. J. Wellensiek 《Euphytica》1961,10(3):259-268
- 1.Most cultivars of Cyclamen persicum are autotetraploids. This implies that true breeding cultivars cannot be obtained by ordinary pedigree selection. Theoretically it could be done by repeated pedigree selection in groups of F4-lines, descended from one F3-line and from one F2-plant, or, expressed in other words, by testing part of the F2-plants not only in F3, but also in F4. It is demonstrated that such a procedure is practically impossible by the large numbers of necessary plants. Therefore, the building up of a complete collection of diploid cultivars is necessary. 相似文献
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S.J. Wellensiek 《Scientia Horticulturae》1973,1(1):77-83
Weekly growth analyses were made of a very late flowering pea line (‘L’) and its medium flowering (‘M’) and early flowering (‘E’) mutants, grown at three photoperiods.The number of stem nodes of young vegetative plants is not affected by the genotype (L, M, E) nor by the day length. In older plants node numbers tend to increase with the day length, but the rate of node formation decreases with flower formation.Internode length is also independent of genotype, but it increases with day length, even in very young plants, and shows a further considerable increase when flower formation starts.Hence, flower formation clearly marks changes in the growth pattern, consisting of a decrease in node formation and an increase in internode length. These effects are primarily brought about by the genes which determine the rate of flower formation. 相似文献