Pperf1b-Like Enhances Lignin Synthesis in Pear (Pyrus Pyrifolia) ‘Hard-End’ Fruit

The hard-end is a disorder of pear fruit, however, the mechanisms underlying its development remain unknown. In this study, we found that the hard-end fruit contained a higher transcript abundance level of () and released more ethylene compared to normal pear. In the ethephon treated normal fruit, flesh tissues accumulated more lignin together with elevated expression of . Overexpressing transiently in fruit and stably in callus increased lignin accumulation and the expression of lignin biosynthesis genes; the opposite results were observed in fruit showing repressed expression of . These results confirmed the role of in promoting hard-end formation through promoting lignin synthesis. This study provided valuable information for further clarifying the regulation of hard-end formation in pear.