However
pollen-tube growth-promoting effects at higher temperatures have
rarely been reported in interspecific crosses. Ascher and Peloquin
(1968) concluded that incubation of styles at 39 ◦C suppressed selfincompatibility,
and had no effect on interspecific incompatibility.
In Tulipa, 14◦C was reported as the optimum temperature for interspecific
crosses (Kho and Baër, 1971). In Brassica, good results were
obtained at 25 ◦C (Matsuzawa, 1983). Sitch and Romero (1990)
reported that temperature had no effect on pollen tube growth in
crosses of Oryza spp.