The Balance between Different ROS on Tobacco Stigma during Flowering and Its Role in Pollen Germination.
Plants (Basel)
; 11(7)2022 Apr 05.
Article
in En
| MEDLINE
| ID: mdl-35406973
ABSTRACT
The concept of ROS as an important factor controlling pollen germination and tube growth has become generally accepted in the last decade. However, the relationship between various ROS and their significance for the success of in vivo germination and fertilization remained unexplored. For the present study, we collected Nicotiana tabacum stigma exudate on different stages of stigma maturity before and after pollination. Electron paramagnetic resonance (EPR) and colorimetric analysis were used to assess levels of Oâ¢2- and H2O2 on stigma. Superoxide dismutase activity in the stigma tissues at each stage was evaluated zymographically. As the pistil matured, the level of both ROS decreased markedly, while the activity of SOD increased, and, starting from the second stage, the enzyme was represented by two isozymes Fe SOD and Cu/Zn SOD, which was demonstrated by the in-gel inhibitory analysis. Selective suppression of Cu/Zn SOD activity shifted the ROS balance, which was confirmed by EPR. This shift markedly reduced the rate of pollen germination in vivo and the fertilization efficiency, which was estimated by the seed set. This result showed that hydrogen peroxide is a necessary component of stigma exudate, accelerates germination and ensures successful reproduction. A decrease in Oâ¢2- production due to NADPH oxidase inhibition, although it slowed down germination, did not lead to a noticeable decrease in the seed set. Thus, the role of the superoxide radical can be characterized as less important.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Plants (Basel)
Year:
2022
Document type:
Article
Affiliation country:
Rusia