Intraspecific C-value variation and the outcomes in Psidium cattleyanum Sabine essential oil

Abstract

Polyploidy, a numerical alteration of the karyotype, is one of the most important mechanisms in plant speciation and diversification, but could also be detected among populations, the cytotypes. For example, Psidium cattleyanum, a polyploid complex, has chromosome numbers ranging from 2n=3x=33 to 2n=12x=132. Polyploidization causes an increase in DNA content, and both modifications may cause alteration in plant growth, physiology, and epigenetics. Based on this possibility, here we aim to verify the influence of the polyploidization on the production of P. cattleyanum essential oil chemotypes. Differences in the DNA contents, as a proxy to different ploidies, were observed and three distinct chemotypes were identified through the chromatographic profile analysis. The Psidium cattleyanum DNA content and qualitative and quantitative characteristics of the essential oils presented a positive relationship. Plants with higher DNA contents presented higher levels of oil production, which was mostly composed of hydrogenated sesquiterpenes, while plants with lower DNA contents produced lower amount of oil, which was mostly composed of hydrogenated monoterpenes. Based on the importance of essential oils, polyploid plants, which present higher DNA content, are recommended as possible matrices for the propagation of new plants with the potential to produce major compounds of agronomic and pharmacological interest.

Genomic and epigenomic variation in Psidium species and their outcome under the yield and composition of essential oils

“…having up to 100 genes) 26,39 and occurrence of lineage-specific pathways and products. Although the essential oil of Psidium species exhibits a great diversity in its chemotypes conditioned to environmental and genetic variations 24,27,40,41 , the evolution of TPS genes in Myrtaceae neotropical fresh fruits remain unknown. The increase of the values of 2C nuclear, CG% and 5-mC% was related to the decrease in (E)-Nerolidol and β-Bisabolol.…”

“…P. cattleyanum plants with the relatively lower nuclear 2C values (2C = 3.23 pg – 2C = 4.71 pg) produced a lower amount of essential oils composed mostly of hydrogenated monoterpenes. Differently, the plants with relatively higher nuclear 2C values (2C = 5.81 pg and 2C = 6.03 pg) produced a higher amount of essential oils composed mostly of hydrogenated sesquiterpenes, as trans-caryophyllene and alpha-humulene 24 .…”

“…Yield and chemical composition of the essential oil. We revisited the data about yield and chemical composition of the essential oil previously published by our research group for P. guajava 40,42 , P. guineense 48 and P. cattleyanum 24 . For the other accesses, the essential oil was extracted based on the methodology used for P. guajava 41 .…”

“…Leaf essential oils, characteristic of the Myrtaceae family secondary metabolism, are rich in terpene and exhibit quali- and quantitative variations reported 24 . Terpenes play ecological roles, and essential oils are economically exploited 25 – 27 for their biological and phytotherapeutic activities 28 .…”