Research

Dr. Sheng Zhong and Prof. Lijia Qu published a paper in Science China Life Sciences.

In angiosperms, fertilization recovery refers to the phenomenon wherein an ovule, upon failure of both sperm cells released by the initial pollen tube to achieve fertilization, continues to attract subsequent pollen tubes to salvage fertilization. Therefore, the efficiency of fertilization recovery is crucial for maximizing fertility. This efficiency primarily depends on the survival rate of the persistent synergid cell (PSC), which secretes pollen tube attractants. However, the relative contributions of the two fertilization events to PSC survival and subsequent fertilization recovery efficiency remain poorly understood. In this study, we utilized mutants defective in either double or single fertilization to assess PSC survival rates and fertilization recovery efficiency under different reproductive scenarios. By providing sufficient pollen through repeated pollination, we observed that the fertilization recovery efficiency in the double fertilization-defective mutant gcs1/hap2 increased from 75.7% to 97.4%, indicating that nearly all PSCs remain viable when double fertilization fails and highlighting the importance of timely and adequate pollen availability for fertilization recovery. Intriguingly, in mutants where egg cell fertilization failed, the PSC persisted in 48.2% of ovules, and about 43.1% of ovules attracted secondary pollen tubes. In contrast, in mutants where central cell fertilization failed, PSC persistence was observed in only 27.5% of the ovules, and fertilization recovery occurred in only 19.9%. These findings demonstrate that egg cell fertilization failure triggers significantly higher efficiency of fertilization recovery than central cell fertilization failure.

Original link: https://www.sciengine.com/SCLS/doi/10.1007/s11427-025-3199-y