Open AccessAn epigenetic breeding system in soybean for increased yield and stability
Author(s) -
Raju Sunil K. Kenchanmane,
Shao MonRay,
Sanchez Robersy,
Xu YingZhi,
Sandhu Ajay,
Graef George,
Mackenzie Sally
Publication year - 2018
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.12919
Subject(s) - biology , epigenetics , gene , transgene , auxin , genetics , phenotype , wild type , arabidopsis , abiotic stress , abiotic component , abscisic acid , mutant , botany , ecology
Summary Epigenetic variation has been associated with a wide range of adaptive phenotypes in plants, but there exist few direct means for exploiting this variation. RNA i suppression of the plant‐specific gene, MutS HOMOLOG 1 ( MSH 1 ), in multiple plant species produces a range of developmental changes accompanied by modulation of defence, phytohormone and abiotic stress response pathways along with methylome repatterning. This msh1‐ conditioned developmental reprogramming is retained independent of transgene segregation, giving rise to transgene‐null ‘memory’ effects. An isogenic memory line crossed to wild type produces progeny families displaying increased variation in adaptive traits that respond to selection. This study investigates amenability of the MSH 1 system for inducing agronomically valuable epigenetic variation in soybean. We developed MSH 1 epi‐populations by crossing with msh1‐ acquired soybean memory lines. Derived soybean epi‐lines showed increase in variance for multiple yield‐related traits including pods per plant, seed weight and maturity time in both glasshouse and field trials. Selected epi‐F 2:4 and epi‐F 2:5 lines showed an increase in seed yield over wild type. By epi‐F 2:6, we observed a return of MSH 1 ‐derived enhanced growth back to wild‐type levels. Epi‐populations also showed evidence of reduced epitype‐by‐environment (e × E) interaction, indicating higher yield stability. Transcript profiling of epi‐lines identified putative signatures of enhanced growth behaviour across generations. Genes related to cell cycle, abscisic acid biosynthesis and auxin response, particularly SMALL AUXIN UP RNA s ( SAUR s), were differentially expressed in epi‐F 2:4 lines that showed increased yield when compared to epi‐F 2:6 . These data support the potential of MSH 1 ‐derived epigenetic variation in plant breeding for enhanced yield and yield stability.