Cytokinin Differences in In Vitro Cultures and Inflorescences from Normal and Mantled Oil Palm (Elaeis guineensis Jacq.)

Abstract

The mantled abnormality phenotype of the oil palm affects fruit development and thus jeopardizes oil yield. Cytokinins have been implicated in the development of the mantled phenotype. Endogenous cytokinin levels in the normal and mantled phenotypes were compared to determine whether levels of specific cytokinins are associated with mantling. Endogenous cytokinins were identified and quantified in in vitro cultures and inflorescences from normal and mantled oil palms. Twenty-two isoprenoid cytokinins, comprising the zeatin, dihydrozeatin, and isopentenyladenine types, were quantified. Total cytokinin levels, particularly of trans-zeatin and isopentenyladenine types, increased during the in vitro culture process, with the highest levels detected at the proliferating polyembryoid stages. The cytokinins were present mainly in their inactive 9-glucoside forms during in vitro culture. On the other hand, the predominant trans-zeatin cytokinins in inflorescences were present mainly in their ribotide forms, suggesting a metabolic pool of cytokinins for conversion to biologically active free bases or ribosides. Levels of specific cytokinins were significantly different in tissues at different stages. Mantled developed inflorescences contained higher levels of isopentenyladenine 9-glucoside compared with normal inflorescences. Mantled-derived callus tissues had higher isopentenyladenine levels but significantly lower levels of trans-zeatin 9-glucoside, dihydrozeatin riboside, and dihydrozeatin riboside 5 0 -monophosphate cytokinins compared with normal-derived callus. It would be of considerable interest to verify these specific cytokinin differences in more callus cultures and clones.

Somaclonal variations and their applications in horticultural crops improvement

“…Eeuwens et al (2002) observed that, in general, a relatively high auxin/cytokinin ratio resulted in the lowest incidence of variant ‘mantled’ flowering in oil palm, while using media supplemented with relatively high cytokinins/auxin ratio resulted in a high incidence of mantled flowering. The role of cytokinin was further confirmed by Ooi et al (2013), who noticed that the mantled inflorescences of oil palm contained higher levels of cytokinins like isopentenyladenine 9-glucoside and lower levels of trans-zeatin 9-glucoside, dihydrozeatin riboside, and dihydrozeatin riboside 5′-monophosphate compared with normal inflorescences.…”

Accelerated in vitro propagation of elite oil palm genotypes (Elaeis guineensis Jacq.) by substituting cytokinin with putrescine

“…Tissue culture through somatic embryogenesis is an attractive alternative to massively propagate elite genotypes of oil palm (Ooi et al, 2013). Nevertheless, the efficiency of plan regeneration is strongly associated with the chosen type of explant.…”

“…For clonal multiplication of oil palm, the somatic embryogenesis has been the most used method (Konan et al, 2006;Ong-Abdullah et al, 2015;Ooi et al, 2013;Palanyandy et al, 2013), and it has already been tested from different explants, such as immature leaves of young plants, immature inflorescences and zygotic embryos (Balzon et al, 2013;Yusnita and Hapsoro, 2011;Rajesh et al, 2003;Scherwinsky-Pereira et al, 2010;Thuzar et al, 2011). It is important to highlight that details for clonal multiplication of oil palm are not published, since researches are conducted by companies with commercial interests, not interested in providing their protocols (Scherwinsky-Pereira et al, 2010).…”

Validasi Metode Analisis Zeatin Menggunakan Teknik Ultra High Performance Liquid Chromatography (UHPLC) sebagai Instrumen Studi Kultur In vitro Kelapa Sawit (Elaeis guineensis Jacq.)

“…Analisis kuantitatif sitokinin yang terkandung di dalam eksplan dibutuhkan untuk memonitor tingkat konsentrasi sitokinin pada fase-fase perkembangan kultur seperti misalnya pada kalus atau embrio. Ooi et al (2013) melaporkan bahwa total level konsentrasi sitokinin meningkat secara bertahap seiring fase perkembangan kultur pada kultur in vitro kelapa sawit asal klon normal dan mantel. Level sitokinin juga cenderung rendah pada tahap kalogenesis dan pemberian auksin secara eksternal untuk menstimulasi embriogenesis mungkin menekan biosintesis sitokinin (Moubayidin et al, 2009).…”