Temperature effects on self incompatibility in Lilium longiflorum.

Detached pistils of the clonal variety, Lilium longiflorum 'Aral No. 5', were submerged before pollination in 50°C water for 0, 1, 2, 3, 4, 5, 6 or 7 min and then immediately compatibly and incompatibly pollinated. Incompatibility, as indicated by pollen tube length after 48 h at 23.5°C, was eliminated by a 1-2 min submersion while compatibility was removed by a 4-5 min one. The 'window' of incubation temperatures at which incompatible and compatible pollen tubes are clearly differentiated occurred between 15 and 30°C.