Recently, the research group of Prof. Huang Rongfeng from Biotechnology Research Institute, Chinese Academy of Agricultural Sciences (BRI, CAAS) has dissected the role of an APETALA2-type transcription factor, SALT AND ABA RESPONSE ERF1 (OsSAE1), as a positive regulator of seed germination and salt tolerance in rice, which provides avenues to improve seed vigor and seedling tolerance via molecular breeding. The results are published on Plant Physiology with the title of “SALT AND ABA RESPONSE ERF1 improves seed germination and salt tolerance by repressing ABA signaling in rice”.

Successful germination is essential for seedling establishment and crop yield but can be adversely added by environmental and hormonal stimuli. AP2 transcription factors, unique to plants, play very important roles in hormonal regulation and stress responses during development, but whether they function in seed germination is unknown. In this study, we provide the first report of an AP2 transcription factor, OsSAE1, functioning during germination and early vegetative development to boost germination and salt tolerance. OsSAE1 negatively regulates abscisic acid sensitivity by directly repressing OsABI5 transcription, shedding light on the function of AP2 proteins in seed germination and abiotic stress responses.

The staple crop rice is particularly susceptible to salinity in early growth stages. This work provides new avenues for molecular breeding of rice varieties with improved salt tolerance, particularly in early seedling development, and with enhanced seed vigour and germination, suitable for saline–alkali land.

This work was funded by National Natural Science Foundation of China, National Key R&D Program of China, and the Agricultural Science and Technology Innovation Program of CAAS.

By Qin Hua (qinhua@caas.cn)