Meiotic polyloidization may contribute to the breeding of polyploid, as
demonstrated in lily (van Tuyl et al., 2005). As odd-numbered polyploids tend to have low
fertility, it is desirable to double the chromosome sets in order to increase fertility and
thus breeding effiency (Kamemoto et al., 1999). To test this concept in Phalaenopsis, we
treated the young flower buds of both Phalaenopsis Sogo Yukidian ‘V3’ and P. Tai Lin
Redangel ‘V31’ cultivars by smearing either colchicine or trifluralin lanolin pastes on
their surface. In Sogo Yukidian ‘V3’, both mitotic inhibitors treatment increased the
frequency of dyad (Table 2), which may contain 2n-gametes, while only colchicine was
effective in increasing dyad frequency of P. Tai Lin Redangel ‘V31’ (Table 3). Trifluralin
did not change the dyad frequency; instead, more micronuclei seemed to be evoked in one
case (Table 3). Using both Phalaenopsis cultivars as model plants to manipulate dyad, we
expect to adopt some diploid and triploid Phalaenopsis cultivars for mitotic inhibitor
treatments to obtain unreduced gametes with 2n-chromosome number.