Ph.D. Program in Plant Molecular Biology

Friday Seminar by Dr. Poonam Mehra

AKT Lab/Friday/August 24, 2018/3.30 pm/ Ethylene-gibberellin signalling underlies adaptation of rice to periodic flooding.
Category: Research

Ethylene-gibberellin signaling underlies adaptation of rice to periodic flooding


More than 16 mha of lowland and deep-water rice areas of the world are unfavourably affected by flooding. Some rice varieties survive submergence by becoming metabolically quiescent to conserve their energy (which involves the Sub1 pathway), whereas others, also called deepwater rice genotypes, respond through rapid internode elongation which elevates their leaves above water level. Recently, researchers have identified gibberellin biosynthesis gene, SD1 (SEMIDWARF1), as being responsible for submergence-induced internode elongation. During submergence, plants carrying the deepwater rice-specific SD1 haplotype directs increased synthesis of gibberellins in ethylene dependent manner. Interestingly, loss-of-function allele of SD1 also hurled the Green Revolution by decreasing gibberellin biosynthesis. Thus, SD1 has been co-opted to allow rice cultivation in highly contrasting production systems through different molecular responses. The capacity of SD1 to function in such diverse roles highlights the intrinsic complexity and molecular plasticity of rice adaptation strategies.


Suggested readings

Kuroha T, Nagai K, Gamuyao R, et al. (2018). Ethylene-gibberellin signaling underlies adaptation of rice to periodic flooding. Science, 361: 181-186.

Sasaki A, Ashikari M, Ueguchi-Tanaka M, et al. (2002). Green revolution: A mutant gibberellin synthesis gene in rice. Nature, 416: 701-702.

Xu K, Xu X, Fukao T, et al. (2006).  Sub1A is an ethylene-response-factor-like gene that confers submergence tolerance to rice. Nature, 442: 705-708.