Abstract. In the conducted experiments the prepared corms of Easy Pot Freesia were soaked directly before planting in ethephon (a source of ethylene) at five concentrations. Ethephon increased the number of offspring corms, but decreased the weight of corms. Among all the used concentrations, irrespective of the cultivar and term of cultivation the effect of concentration of 2000 mg·dm^-3 was the strongest.

The size and quality of yield of offspring corms of Easy Pot freesia depending on concentration of ethephon

Summary

Experiments were carried out in the years 2000-2001, in spring-summer season, in unwarmed plastic tunnel. Plant material consisted of prepared corms of three cultivars of Easy Pot freesia: ‘Gompey’, ‘Popey’ and ‘Suzy’. Directly before planting corms were treated for 24 hours with ethephon at concentrations of: 125, 250, 500, 1000, 2000 mg·dm^-3 (Flordimex 420 SL and Ethrel 480 SL). Corms soaked in water served as the control. Plants were cultivated in plastic pots N^o14 (1 dm³).

Yield of offspring corms was estimated after their drying, cleaning and sorting. After vegetation the coefficients of weight increase and corm number increase were calculated.

Treating of corms before planting with ethephon at concentrations of 125-2000 mg·dm^-3 affects the yield of offspring corms of Easy Pot freesia. Although there was no effect on total weight of corms, ethephon at the rate of 125 and 250 mg·dm^-3 increased the number of corms. At the rate of 1000 and 2000 mg·dm^-3 ethephon considerably decreased the weight of the obtained corms, but decreased their number. Although the obtained corms were small, they were properly formed.