Controlled crosses of 'Sunki' with Poncirus trifoliata and its hybrids were
performed in order to estimate the zygotic seedlings frequency, by compari
ng its vigour with the ones from nucellar origin. A relatively high fruit s
et rate of 40% was achieved, which indicates a good compatibility within th
e parental crosses. The observed frequency of zygotic seedlings was 48% and
certainly this was underestimated due to the presence of Poncirus hybrids
in the pollinations. Epicotyl length and the true leaf number character est
imates showed that 91% of the identified hybrids may be similar or even sup
erior to the nucellar ones in relation to plant vigour.