The pre-treatment of dark promoted rooting of P. pyrifolia cv. Shenbuzhi and P. bretschneideri cv. Zaosu, but inhibited rooting of P. communis cv. Bartlett and Comice.

• 前期暗培养能有效促进东方梨品种早酥梨和身不知根的发生,而对西洋梨品种巴梨和考密斯根的诱导效果较差。