Next Article in Journal
Pathological and Epidemiological Characterization of First Outbreak of Daylily Rust in Europe and Evaluation of Puccinia hemerocallidis Resistance in Hemerocallis Cultivars
Previous Article in Journal
Hydrothermal Carbonization and Pellet Production from Egeria densa and Lemna minor
Open AccessReview

Citrus Polyamines: Structure, Biosynthesis, and Physiological Functions

by Nabil Killiny 1,* and Yasser Nehela 1,2
1
Citrus Research and Education Center and Department of Plant Pathology, IFAS, University of Florida, Lake Alfred, FL 33850, USA
2
Department of Agricultural Botany, Faculty of Agriculture, Tanta University, Tanta 31527, Egypt
*
Author to whom correspondence should be addressed.
Plants 2020, 9(4), 426; https://doi.org/10.3390/plants9040426
Received: 2 March 2020 / Revised: 17 March 2020 / Accepted: 24 March 2020 / Published: 31 March 2020
Polyamines (PAs) are ubiquitous biogenic amines found in all living organisms from bacteria to Archaea, and Eukaryotes including plants and animals. Since the first description of putrescine conjugate, feruloyl-putrescine (originally called subaphylline), from grapefruit leaves and juice, many research studies have highlighted the importance of PAs in growth, development, and other physiological processes in citrus plants. PAs appear to be involved in a wide range of physiological processes in citrus plants; however, their exact roles are not fully understood. Accordingly, in the present review, we discuss the biosynthesis of PAs in citrus plants, with an emphasis on the recent advances in identifying and characterizing PAs-biosynthetic genes and other upstream regulatory genes involved in transcriptional regulation of PAs metabolism. In addition, we will discuss the recent metabolic, genetic, and molecular evidence illustrating the roles of PAs metabolism in citrus physiology including somatic embryogenesis; root system formation, morphology, and architecture; plant growth and shoot system architecture; inflorescence, flowering, and flowering-associated events; fruit set, development, and quality; stomatal closure and gas-exchange; and chlorophyll fluorescence and photosynthesis. We believe that the molecular and biochemical understanding of PAs metabolism and their physiological roles in citrus plants will help citrus breeding programs to enhance tolerance to biotic and abiotic stresses and provide bases for further research into potential applications. View Full-Text
Keywords: citrus; polyamines; putrescine; spermidine; spermine; embryogenesis; root system architecture; shoot system architecture; flowering and inflorescence citrus; polyamines; putrescine; spermidine; spermine; embryogenesis; root system architecture; shoot system architecture; flowering and inflorescence
Show Figures

Figure 1

MDPI and ACS Style

Killiny, N.; Nehela, Y. Citrus Polyamines: Structure, Biosynthesis, and Physiological Functions. Plants 2020, 9, 426.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop