Department of Horticulture
PhD Graduate Research Assistant
Telephone: (517) 940-1466
East Lansing, MI 48824, USA
Plant Breeding, Genetics, and Biotechnology
Using the Regulation of GA2ox as a Model to Understand Gibberellin's Roles in Flowering and Response to Abiotic Stress
Area of Expertise
Flowering; abiotic stress; regulation of GA2ox genes; GUS reporter system; CRISPR/Cas9 gene editing
- Ph.D. in Horticulture, Michigan State University, USA May 2021 (expected)
- M.S. in Horticulture, Northwest A&F University, Yangling, China Jun. 2016
- B.S. in Agriculture, Northwest A&F University, Yangling, China Jun. 2013
Songwen is currently looking at the role of phytohormone gibberellins (GAs) in apple flowering under the supervision of Dr. Steve van Nocker. In contrast to its promotive role in floral induction in Arabidopsis, exogenous GA application during the summer period of floral induction can reduce bloom density and crop load in the subsequent year in apple and many other fruit trees. However, the mechanism of GA-mediated flowering repression in apple and other plants remains unknown. She is addressing this deficiency of knowledge by documenting the transcriptional response of apple trees to exogenous GA application, and by identifying specific components in the mechanism linking GA perception with gene response, using the positive regulation of the GA2ox gene family by GA in model plant Arabidopsis. In addition to flowering, Songwen has also developed strong interest in abiotic stress responses in plants. She is studying how GA is involved in abiotic stress response, specifically, through the regulation of GA2ox. Songwen has generated a series of GUS-fusion lines and CRISPR/Cas9-induced knockout lines of Arabidopsis GA2ox, which are enabling her to answer the scientific questions above. She hopes to exploit the findings from these studies to design more efficient, GA-based methods to control flowering, while also identifying genetic loci that may be important for the development of new cultivars with desirable flowering traits and improved tolerance to abiotic stress
Awards and Scholarships
- The Graduate School Dissertation Completion Fellowship 2020-2021
- PBGB Graduate Award 2020
- Dr. Ruth M. Allen Award 2018-2019
- The Jason and Dana Lilly Award 2018-2019
- The John L. Arend Excellence in Graduate Student Research 2018-2019
- Horticulture Graduate Office Fellowship Award 2016-2017
- Mericle Memorial Scholarship
- 2019-2020 Co-President of the Horticultural Organization of Graduate Students (HOGS)
- 2018-2019 Member of Departmental Newspaper of Horticulture (HortReport)
- 2018-2019 Faculty Representative of HOGS
2016-2017 Professional Development Chair of HOGS
Zhang, S., Gottschalk, C. and van Nocker, S., 2019. Genetic mechanisms in the repression of flowering by gibberellins in apple (Malus x domestica Borkh.). BMC genomics, 20(1), p.747.
Zhang, S., Zhang, D., Fan, S., Du, L., Shen, Y., Xing, L., Li, Y., Ma, J. and Han, M., 2016. Effect of exogenous GA3 and its inhibitor paclobutrazol on floral formation, endogenous hormones, and flowering-associated genes in ‘Fuji’ apple (Malus x domestica Borkh.). Plant Physiology and Biochemistry, 107, pp.178-186.
Gottschalk, C., Zhang, S., Schwallier, P., Rogers, S., Bukovac, M.J., and Van Nocker, S., 2021. Genetic mechanisms associated with floral initiation and the repressive effect of fruit on flowering in apple (Malus x domestica Borkh.). PLOS ONE (accepted).
Du, L., Qi, S., Ma, J., Xing, L., Fan, S., Zhang, S., Li, Y., Shen, Y., Zhang, D. and Han, M., 2017. Identification of TPS family members in apple (Malus x domestica Borkh.) and the effect of sucrose sprays on TPS expression and floral induction. Plant Physiology and Biochemistry, 120, pp.10-23.
Li, Y., Zhang, D., Xing, L., Zhang, S., Zhao, C. and Han, M., 2016. Effect of exogenous 6-benzylaminopurine (6-BA) on branch type, floral induction and initiation, and related gene expression in ‘Fuji’apple (Malus domestica Borkh). Plant Growth Regulation, 79(1), pp.65-70.
Xing, L., Zhang, D., Li, Y., Zhao, C., Zhang, S., ... & Han, M. 2014. Genome-wide identification of vegetative phase transition-associated microRNAs and target predictions using degradome sequencing in Malus hupehensis. BMC genomics, 15(1), 1125.