Tissue Culture of Oil Palm: Finding the Balance Between Mass Propagation and Somaclonal Variation

Abstract

The oil palm ( Elaeis guineensis Jacq.) is typically propagated in vitro by indirect somatic embryogenesis, a process in which somatic cells of an explant of choice are, via an intermediate phase of callus growth, induced to differentiate into somatic embryos. The architecture of the oil palm, lacking axillary shoots, does not allow for vegetative propagation. Therefore, somatic embryogenesis is the only alternative to seed propagation, which is hampered by long germination times and low germination rates, for the production of planting material. The current oil palm somatic embryogenesis procedure is associated with several difficulties, which are described in this review. The limited availability of explants, combined with low somatic embryo initiation and regeneration rates, necessitate the proliferation of embryogenic structures, increasing the risk for somaclonal variants such as the mantled phenotype. Several ways to improve the efficiency of the tissue culture method and to reduce the risk of somaclonal variation are described. These include the use of alternative explants and propagation techniques, the introduction of specific embryo maturation treatments and the detection of the mantled abnormality in an early stage. These methods have not yet been fully explored and provide interesting research field for the future. The development of an efficient oil palm micropropagation protocol is needed to keep up with the increasing demand for palm oil in a sustainable way. Mass production of selected, high-yielding palms by tissue culture could raise yields on existing plantations, reducing the need for further expansion of the cultivated area, which is often associated with negative environmental impacts.

Progress in Tissue Culture and Genetic Transformation of Oil Palm: An Overview

“…In vitro propagation of oil palm via indirect somatic embryogenesis involves the three main developmental stages: induction of callus from the desired ex-plant, induction of embryoid-like structures (somatic embryos), somatic embryo maturation, and plantlet regeneration (Figure 1). However, it should be kept in mind that the somatic embryogenesis of oil palm is greatly influenced by the type of ex-plant, the composition of media, plant growth regulators, culture conditions, the number and duration of subcultures, and genotype selection [3,10,25,26]. For the induction of embryogenic callus, researchers commonly used two types of plant growth regulators, such as auxins (2,4-dichlorophenoxyacetic acid (2,4-D) and picloram).…”

“…For the induction of embryogenic callus, researchers commonly used two types of plant growth regulators, such as auxins (2,4-dichlorophenoxyacetic acid (2,4-D) and picloram). However, 2,4-D has been extensively used for embryogenic callus (EC) induction [3] (Table 1). Indeed, EC induction is greatly influenced by concentrations of auxins with or without activated charcoal (AC) (9–10 μM without AC or 450 μM with 2.5–3 g/L AC) (Table 1).…”

“…Oil palm ( Elaeis guineensis Jacq.) cultivation has emerged as the world’s major cultivated crops, being grown on more than 16 million hectares [3,4,5]. The demand for palm oil has increased and will increase further in the coming years to target more than 200 million tons of the total global production of fats and oils [6,7,8], making palm oil the most traded vegetable oil [9].…”

Ethylene mediated physiological response for in vitro development of salinity tolerant tomato

“…These are genetic and/or epigenetic changes induced in cultured plant cell and entire tissue. It is an alternating tool to conventional breeding to instigate advantageous genetic variability in the existing gene pool (Weckx et al 2019). In the global change in environment, the developments of abiotic and biotic stress-tolerant crops are of great concern.…”

Effect of Plant Gowth Regulator on The Gowth of Zygotic Embryos in Three Types of Oil Palm Fruit (Elaeis guineensis Jacq.) in Tissue Culture

“…Around 98% of oil palm planting material therefore consists of hybrid seeds (Kushairi et al, 2010). Because the oil palm only has one meristem, it must be propagated in vitro by indirect somatic embryogenesis SE (Weckx et al, 2019). Meanwhile, vegetative propagation of oil palm such as tissue culture is still very limited (Sunarko, 2014).…”