TITLE:
An Ethylene Over-Producing Mutant of Tomato (Solanum lycopersicum), Epinastic, Exhibits Tolerance to High Temperature Conditions
AUTHORS:
Sridharan Jegadeesan, Etan Pressman, Avital Beery, Vikram Singh, Lázaro Eustáquio Pereira Peres, Sara Shabtai, Nurit Firon
KEYWORDS:
Ethylene, Mild Chronic Heat Stress, Pollen Grains, Reproduction, Solanum lycopersicum, Thermotolerance
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.12 No.4,
April
6,
2021
ABSTRACT: Above-optimal temperatures reduce yield in many
crops, including tomato, largely because of the heat-sensitivity of their
reproduction process. A full understanding of heat-stress (HS) response and
thermotolerance of tomato reproduction is still lacking. Recently, using
external application of the plant hormone
ethylene, it was demonstrated that ethylene plays a role in heat-tolerance
of tomato pollen (the male reproductive cells). In order to expand our
understanding on involvement of ethylene in tomato pollen thermotolerance, we analyzed the response of wild type and
ethylene-related tomato mutant plants
to HS, at physiological and molecular levels. We report that mild chronic HS conditions highly reduce the
number of viable and germinating pollen grains as well as the production
of seeded fruits in wild type tomato plants, while no significant reduction was
detected/observed in pollen quality, number of seeded fruits and seeds per
fruit in plants of the ethylene over-producer mutant epinastic. Our findings suggest that ethylene is involved in
thermotolerance of tomato reproduction, pointing to an effect on pollen
viability and germination potential,
highlighting candidate genes involved in pollen response to HS (like SlHSP17, SlHSP101, SlMBF1) and suggesting directions for further studies.