From Embryo to Adult: Low Temperatures Affect Phase Transitions of Allium sativum L. from Germination to Flowering

Agronomy

TomerE. Ben Michael¹  JoshuaD. Klein¹  Itzhak Forer¹  RinaKamenetsky Goldstein¹  Ross Peters¹  Liraz Rozenblat¹  Adi Faigenboim¹  Einat Shemesh-Mayer¹  HaimD. Rabinowitch² 

[1] Institute of Plant Sciences, ARO, The Volcani Center, POB 6, Rishon LeZion 7505101, Israel;Robert H. Smith Faculty of Agricultural, Food, and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel;

关键词: stratification;    vernalization;    shoot apical meristem;    geophyte;    bulb;   

DOI  :  10.3390/agronomy10111651

来源: DOAJ

【 摘 要 】

Juvenile and vegetative adult shoot apical meristems (SAM) are actively involved in acquisition of flowering competence, while the embryonic SAM is regarded as “responsible” only for germination. Comparative analyses of imbibed and stratified seeds of garlic Allium sativum show that only stratified seedlings produced bulbs and flower stems at the end of the season. Since the seed morphology of stratified and non-stratified seeds prior to sowing was similar, the differences are attributed to the molecular alterations in the embryonic SAM. Functional annotation analysis of 3000 differentially expressed genes suggests that seed imbibition reactivates the embryonic cell cycle, initiates the metabolism, and primes garlic seed germination. Stratification enhances DNA modifications, biosynthesis, cellular transport, and tissue development. Similar to vernalization of the vegetative buds, stratification of the embryonic SAM resulted in altered expression of meristem-identity and flowering homologs. Phase transitions from seed germination to flowering and bulbing in A. sativum are tightly connected, and possibly associated with downregulation of specific flowering repressor(s). The embryonic SAM plays an important role not only in seed germination, but in the entire plant life cycle, providing the foundation for the genetic regulation of major functional shifts in metabolism and development.

【 授权许可】

Unknown