Breeding new varieties, especially homozygous lines, is a time-consuming process, as the number of plant generations per year is limited. By prolonging the photoperiod and increasing the planting density, we aimed to accelerate the 18generation cycle of donor plants of oilseed rape (Brassica napus L.) and check whether this affects the induction of haploids through microspore culture, which is the most used method for obtaining homozygous oilseed rape plants. Plants were illuminated with 16-hour or 22-hour photoperiods and planted at a density of 1 or 3 plants per pot (diameter 13 cm). When 2 flowers appeared, we continued to isolate and grow microspores according to the protocol published by Custers (2003). We found that plants bloomed faster under the 22-hour photoperiod, and that planting density had no effect on faster induction of flowering. We also found that we obtained the highest number of embryos per bud from plants grown under the 22-hour photoperiod and at higher planting densities. Although we have successfully accelerated generation time of the donor plants, they were small with a low number of buds, which is not suitable for breeding techniques where larger quantities of buds and seeds are required.
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