This chapter discusses the geographical distribution of basal stem rot (BSR; caused by Ganoderma spp.) of oil palm (Elaeis guineensis), the symptoms of BSR disease, economic importance, epidemiology (mycelium contact and Ganoderma basidiospores), predisposition factors associated with BSR disease (e.g. age of oil palm, previous crops, soil type, nutrient status and planting technique), early detection of BSR, and management strategies for BSR (including cultural, chemical and biological control).

Fungicide is used to control fungal disease by destroying and inhibiting the fungus or fungal spores that cause the disease. However, failure to deliver fungicide to the disease region leads to ineffectiveness in the disease control. Hence, in the present study, nanotechnology has enabled the fungicide active agents (hexaconazole) to be encapsulated into chitosan nanoparticles with the aim of developing a fungicide nanodelivery system that can transport them more effectively to the target cells (Ganoderma fungus). A pathogenic fungus, Ganoderma boninense (G. boninense), is destructive to oil palm whereby it can cause significant loss to oil palm plantations located in the Southeast Asian countries, especially Malaysia and Indonesia. In regard to this matter, a series of chitosan nanoparticles loaded with the fungicide, hexaconazole, was prepared using various concentrations of crosslinking agent sodium tripolyphosphate (TPP). The resulting particle size revealed that the increase of the TPP concentration produced smaller particles. In addition, the in vitro fungicide released at pH 5.5 demonstrated that the fungicide from the nanoparticles was released in a sustainable manner with a prolonged release time up to 86 h. On another note, the in vitro antifungal studies established that smaller particle size leads to lower half maximum effective concentration (EC50) value, which indicates higher antifungal activity against G. boninense.

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The increase in the world’s oil demand due to the rise of the global population urges more research into the production of sustainable vegetable oilseeds, among which palm oil is the most suitable candidate as it is the most efficient oilseed crop in the world. In an effort to drive the oil palm industry in the areas of food safety and security nanotechnology could offer a sustainable alternative. However, the utilization of nanotechnology in the oil palm industry is still limited. In this review, we aim to encourage the researchers to fully utilize nanotechnology as an alternative solution to tackle the challenges faced by the oil palm industry. Moreover, we also aim to highlight the opportunities for nanotechnology development in oil palm-based related research. The major points are as follows: (1) Nanosensing enables real-time monitoring of plantation status and crop progression, including soil, water and nutrient management, early pest/disease detection, and the spreading of pests/diseases. The use of nanosensing conveniently extends into advanced breeding topics, such as the development of disease-tolerant plants; (2) Nanotechnology could be the answer for the development of integrated management of pest and disease. Active agricultural ingredients can be entrapped or encapsulated into nanocarrier systems to improve their solubility, stability, enhance their efficient delivery to site-specific targets, with longer shelf life, and consequently improved efficacy; (3) Valuable nanomaterials can be isolated and generated from oil palm biomass waste. The utilization of oil palm biomass waste could overcome the issue of the massive production of waste in the oil palm industry and palm oil mills, where oil only accounts for 10% of the biomass, while 90% is comprised of the generated biowastes. (4) Palm oil can be utilized as a green alternative as a capping and stabilizing agent in the biosynthesis of metallic and non-metallic nanoparticles. In addition, nanoemulsion formulations using palm oil in drug delivery systems offer advantages such as low toxicity, enhance bioavailability and solubility of the drugs, apart from being inexpensive and environmentally friendly.

A fungicide, hexaconazole was successfully intercalated into the intergalleries of zinc/aluminum-layered double hydroxide (ZALDH) using the ion-exchange method. Due to the intercalation of hexaconazole, the basal spacing of the ZALDH was increased from 8.7 Å in ZALDH to 29.4 Å in hexaconazole-intercalated ZALDH (HZALDH). The intercalation of hexaconazole into the interlayer of the nanocomposite was confirmed using the Fourier-transform infrared (FTIR) study. This supramolecular chemistry intercalation process enhanced the thermal stability of the hexaconazole moiety. The fungicide loading was estimated to be 51.8%. The nanodelivery system also shows better inhibition toward the Ganoderma boninense growth than the counterpart, free hexaconazole. The results from this work have a great potential to be further explored for combating basal stem rot (BSR) disease in oil palm plantation.

Balanced nutrient elements in fertilizer play a critical role in oil palm seedling successful growth and development, and at the same time reduces of fertilizer losses in the environment. This study examines the effect of different levels of N, P 2 O 5 and K 2 O for oil palm seedlings in solution culture on growth traits, nutrient uptake in plant tissues and biomass accumulation under nursery conditions. Five concentration levels of N (50, 100, 300, 600 and 900 mg L ) were used in a completely randomized design (CRD) with five replications for each. Parameters measured during the growing period include -plant height, leaf number/plant, stem diameter, SPAD chlorophyll value, and at harvest -total leaf area, root dry weight, shoot dry weight and total dry weight. Different levels of N, P 2 O 5 and K 2 O showed significant effects on all the parameters studied. The highest values for diameter, plant height, leaf number/plant, total leaf area, root dry weight, shoot dry weight and total dry biomass were obtained using 100, 90 and 300 mg/L levels of N, P 2 O 5 and K 2 O, respectively. Most of the growth parameters, declined with lower levels of N, P 2 O 5 and K 2 O. The results of this study provide a new knowledge to produce oil palm plant with better nutrient management at the nursery under solution culture.

Thiamine, or vitamin B1 plays an indispensable role as a cofactor in crucial metabolic reactions including glycolysis, pentose phosphate pathway and the tricarboxylic acid cycle in all living organisms. Thiamine has been shown to play a role in plant adaptation toward biotic and abiotic stresses. The modulation of thiamine biosynthetic genes in oil palm seedlings was evaluated in response to root colonization by endophytic Hendersonia toruloidea. Seven-month-old oil palm seedlings were inoculated with H. toruloidea and microscopic analyses were performed to visualize the localization of endophytic H. toruloidea in oil palm roots. Transmission electron microscopy confirmed that H. toruloidea colonized cortical cells. The expression of thiamine biosynthetic genes and accumulation of total thiamine in oil palm seedlings were also evaluated. Quantitative real-time PCR was performed to measure transcript abundances of four key thiamine biosynthesis genes (THI4, THIC, TH1, and TPK) on days 1, 7, 15, and 30 in response to H. toruloidea colonization. The results showed an increase of up to 12-fold in the expression of all gene transcripts on day 1 post-inoculation. On days 7, 15, and 30 post-inoculation, the relative expression levels of these genes were shown to be downregulated. Thiamine accumulation was observed on day 7 post-colonization and subsequently decreased until day 30. This work provides the first evidence for the enhancement of thiamine biosynthesis by endophytic colonization in oil palm seedlings.

The use of nanotechnology could play a significant role in the agriculture sector, especially in the preparation of new-generation agronanochemicals. Currently, the economically important plant of Malaysia, the oil palm, faces the threat of a devastating disease which is particularly caused by a pathogenic fungus, Ganoderma boninense. For the development of an effective antifungal agent, a series of chitosan nanoparticles loaded with a fumigant, dazomet, were prepared using various concentrations of sodium tripolyphosphate (TPP)—2.5, 5, 10, and 20 mg/mL, abbreviated as CDEN2.5, CDEN5, CDEN10, and CDEN20, respectively. The effect of TPP as a crosslinking agent on the resulting particle size of the synthesized nanoparticles was investigated using a particle size analyzer and high-resolution transmission electron microscopy (HRTEM). Both methods confirmed that increasing the TPP concentration resulted in smaller particles. In addition, in vitro fumigant release at pH 5.5 showed that the release of the fumigant from the nanoparticles was of a sustained manner, with a prolonged release time up to 24 h. Furthermore, the relationship between the chitosan-dazomet nanoparticles and the in vitro antifungal activity against G. boninense was also explored, where the nanoparticles of the smallest size, CDEN20, gave the highest antifungal efficacy with the lowest half maximum effective concentration (EC50) value of 13.7 ± 1.76 ppb. This indicates that the smaller-sized agronanoparticles were more effective as an antifungal agent. The size can be altered, which plays a crucial role in combatting the Ganoderma disease. The agronanoparticles have controlled release properties and high antifungal efficacy on G. boninense, thus making them a promising candidate to be applied in the field for Ganoderma treatment.