LAUSR

The hard-end of pear fruit might be a disorder of the environmental abiotic stress, which is mainly caused by the reduced water intake of the fruit resulting from climate drought. To explore the factors that cause fruit hard-end, two rootstocks of Pyrus betulaefolia and P. bretschneideri with different root absorptive capacity of water and nutrients were used as base stock of ‘Whangkeumbae’ (P. pyrifolia) pear fruit. The results showed that the incidence of hard-end fruit in ‘Whangkeumbae’ pear trees using rootstock with lower rate of water absorptive increased, indicating that this physiological disorder was related with water deficiency. PpNAC187 was selected from RNA-Seq carried out on the calyx end of with and without the hard-end symptom of different rootstocks. The transgenic tobacco overexpressing PpNAC187 showed higher tolerance with drought and salt stress, which might suggest that PpNAC187 acts an important role during the hard-end occurring caused by drought or salt stress.