Relationship between Coleoptile Elongation and Alcoholic Fermentation in Rice Exposed to Anoxia. II. Cultivar Differences uri icon

abstract

  • Coleoptile growth under anoxia was related to rates of ethanol synthesis (R(E)), however differences between growth during anoxia and survival after anoxia indicated that post-anoxic injury may also be important in rice seeds exposed to anoxia. The correlation between coleoptile growth and R(E) measured on a tissue basis using intact seeds was r(2) = 0.67 among six varieties over 0-3 d anoxia. This correlation improved to about r(2) = 0.85 using R(E) of (embryos plus coleoptiles) over 0-3 d, or coleoptiles at 3 d after anoxia. Coleoptile growth of individual seeds was usually poorly correlated to R(E) in these cultivars at 2-3 d after anoxia. When coleoptiles of similar lengths were obtained from different cultivars using 4 d aerated seeds, there were differences in R(E) and coleoptile growth which were related to coleoptile growth during 3 or 5 d anoxia, either on a tissue (r(2) = 0.85) or a fresh weight basis (r(2) = 0.70-0.97 respectively). Results are discussed in relation to factors which may limit ethanol synthesis in rice exposed to anoxia and the importance of growth to the survival of seeds and mature plants during submergence in the natural environment.
  • The relationship between coleoptile elongation and survival vs. alcoholic fermentation of rice under anoxia is examined using eight cultivars differing in submergence tolerance. Anoxia was imposed on either 1 or 4 d aerated seeds either by N-2 flushing submerged tissues or by incubating tissues in stagnant deoxygenated agar at 0.1 % w/v; the latter simulated the stagnant conditions of waterlogged soil, Two cultivars that were most tolerant to submergence also had the greatest tolerance to anoxia, while a submergence intolerant cultivar was also intolerant to anoxia.

publication date

  • 1994
  • 1994