Abstract
Pluronic F-68 (PF-68) is a non-ionic surfactant used in plant tissue culture as a growth additive. Despite its usage as a plant growth enhancer, the mechanism underlying the growth-promoting effects of PF-68 remains largely unknown. Hence, this study was undertaken to elucidate the growth-promoting mechanism of PF-68 using recalcitrant MR 219 callus as a model. Supplementation of 0.04% PF-68 (optimum concentration) was shown to enhance callus proliferation. The treated callus recorded enhanced sugar content, protein content, and glutamate synthase activity as exemplified in the comparative proteome analysis, showing protein abundance involved in carbohydrate metabolism (alpha amylase), protein biosynthesis (ribosomal proteins), and nitrogen metabolism (glutamate synthase), which are crucial to plant growth and development. Moreover, an increase in nutrients uptake was also noted with potassium topping the list, suggesting a vital role of K in governing plant growth. In contrast, 0.10% PF-68 (high concentration) induced stress response in the callus, revealing an increment in phenylalanine ammonia lyase activity, malondialdehyde content, and peroxidase activity, which were consistent with high abundance of phenylalanine ammonia lyase, peroxidase, and peroxiredoxin proteins detected and concomitant with a reduced level of esterase activity. The data highlighted that incorporation of PF-68 at optimum concentration improved callus proliferation of recalcitrant MR 219 through enhanced carbohydrate metabolism, nitrogen metabolism, and nutrient uptake. However, growth-promoting effects of PF-68 are concentration dependent.
Highlights
Rice is one of the major staple foods serving more than half of the population of the world (Hadiarto and Tran, 2011)
The present study demonstrates that the growth-promoting effects of Pluronic F-68 (PF-68) are independent of a plant hormone
The comparative proteome analysis revealed that optimum PF-68 concentration enhanced callus proliferation of MR 219 cultivar via enhanced sugar accumulation and protein biosynthesis. This was evidenced by the increase in the abundance of carbohydrate metabolism-related proteins, ribosomal proteins, and nitrogen metabolism-related proteins (Figure 5)
Summary
Rice is one of the major staple foods serving more than half of the population of the world (Hadiarto and Tran, 2011). Increasing rice production should be prioritized in order to sustain the ever-increasing world population (Sen et al, 2020). Through the advancement of modern biotechnology, genetic manipulation could serve as an alternative solution to meet the increasing demands of rice production (Low et al, 2018). Genetic manipulation in indica rice cultivars remains a challenge. This is because indica rice cultivars share common recalcitrant properties toward in vitro regeneration responses. In order to improve the in vitro responses of indica rice cultivar, optimization of the plant growth medium is required
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
