Analysis of Large Seeds from Three Different Medicago truncatula Ecotypes Reveals a Potential Role of Hormonal Balance in Final Size Determination of Legume Grains.
Legume seeds are important as protein and oil source for human diet. Understanding how their final seed size is determined is crucial to improve crop yield. In this study, we analyzed seed development of three accessions of the model legume, Medicago truncatula, displaying contrasted seed size. By comparing two large seed accessions to the reference accession A17, we described mechanisms associated with large seed size determination and potential factors modulating the final seed size. We observed that early events during embryogenesis had a major impact on final seed size and a delayed heart stage embryo development resulted to large seeds. We also observed that the difference in seed growth rate was mainly due to a difference in embryo cell number, implicating a role of cell division rate. Large seed accessions could be explained by an extended period of cell division due to a longer embryogenesis phase. According to our observations and recent reports, we observed that auxin (IAA) and abscisic acid (ABA) ratio could be a key determinant of cell division regulation at the end of embryogenesis. Overall, our study highlights that timing of events occurring during early seed development play decisive role for final seed size determination.
The Samuel Roberts Noble Foundation, Plant Biology Division, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA. kaustav_01@yahoo.co.in.
Kaustav
K
Bandyopadhyay
The Samuel Roberts Noble Foundation, Plant Biology Division, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA. orhanulucay@gmail.com.|Kafkas University-Faculty of Engineering and Architecture, Central Campus, Kars 36100, Turkey. orhanulucay@gmail.com.
Orhan
O
Uluçay
Kafkas University-Faculty of Engineering and Architecture, Central Campus, Kars 36100, Turkey. msakiroglu@gmail.com.
Muhammet
M
Şakiroğlu
The Samuel Roberts Noble Foundation, Plant Biology Division, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA. mudvardi@noble.org.
Michael K
MK
Udvardi
The Samuel Roberts Noble Foundation, Plant Biology Division, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA. javerdier@icloud.com.|Shanghai Center for Plant Stress Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, 3888 Chenhua Road, Shanghai 201602, China. javerdier@icloud.com.
Jerome
J
Verdier
D000040:Abscisic Acid / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000378:metabolism*; D046913:Medicago truncatula / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D063245:Plant Development; D012639:Seeds / Q000254:growth & development* / Q000378:metabolism
D007210:Indoleacetic Acids; D000040:Abscisic Acid
Medicago truncatula; abscisic acid; auxin; cell division; embryogenesis; legume grains; seed size