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Agarwood is a resinous wood produced by some members of plant family Thymelaeaceae under certain conditions. Agarwood is highly prized, but its formation requires a long-time process in nature. Therefore, various induction techniques have been explored to hasten the process. In this study, we induced agarwood in Gyrinops versteegii, one of the most abundant agarwood-producing trees in Indonesia. We used 12 trees and wounded four branches on each tree through an injection process. We used two strains of the endophytic fungi Fusarium solani isolated from Gorontalo and Jambi Provinces. After 3 months, the inoculated wood had an extensive resinous zone, when compared to wounded control wood. Gas chromatographic-mass spectrometric analysis of the inoculated samples revealed the presence of several sesquiterpenes characteristic of agarwood. These included alloaromadendrene, β-eudesmol and β-selinene as well as the chromone derivatives 2-(2-phenylethyl) chromen-4-one, 6-methoxy-2-(2-phenylethyl) chromen-4-one, and 6,7-dimethoxy-2-(2-phenylethyl) chromen-4-one. We conclude that this method successfully induced agarwood to form in a matter of months and could be used to enhance the success of agarwood cultivation.

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Phytophthora capsici is one of the primary pathogens causing a global problem of severe losses in chilli production. The use of conventional fertilisers and fungicides to improve chilli production had been shown to elevate environmental and health issues. Hence, the foliar application of chitosan, natural deacylated chitin, to enhance growth and resistance in chilli pepper plants was investigated. The chilli plants were grown for 14 days before receiving chitosan application and 33 days before Phytophthora infection, physiological parameters were recorded during the growth period, and expression of resistance related genes was quantified at 72 hours after infection. Our results showed that physiological parameters, such as increment of height and leaves number, and chlorophyll content indicated an improved growth process in chitosan treated plants compared to the control. Plant resistance to Phytophthora infection was also investigated following chitosan application to highly (CM334), moderately (LABA), weakly (LADO) resistant and susceptible (15080) cultivars. The disease incidence and severity indices were reduced in chitosantreated plants, except in highly and moderately resistant cultivars. Further, expression was also quantified for defence-related genes, including 9-lipoxygenase (CaLOX), Ca2+-bound calmodulin 1 (CaCaM1), receptor-like cytoplasmic protein kinase (CaPIK), Pto-interacting1 (CaPTI1) and resistance gene analogue 2 (CaRGA2). The results suggest that CaLOX, CaPTI1 and CaRGA2 genes were involved in defence mechanism to Phytophthora, with increased expression during infection. However, expression levels were reduced when Phytophthora infection was coupled with foliar chitosan application, indicating that chitosan may play a direct role in decreasing the pathogenicity of Phytophthora. In conclusion, this study suggests the promising role of chitosan as an alternative to conventional fertiliser and fungicide in chilli pepper plant.

Steviol glycosides contained in Stevia leaves have considerable potential uses for the natural sweetener industry due to it's antidiabetic properties, hence a large number of plant source is required to supply the industry. To overcome the hindrances in the propagation of Stevia plants using in vivo methods, an alternative technique of propagation using in vitro methods is needed. The micropropagation method with the RITA® (Recipient for Automated Temporary Immersion System) is used in the production of a large amount of stevia biomass in approximately a short period. The forming of flowers is one of the limiting factors interfering with the metabolite production, as the content of steviol glycoside will decrease after plant flowering dramatically. This mechanism happened because steviol glycoside synthesis and flowering process share the same precursor. However, this interfering factor could be inhibited by using a high-red LED induction to delay the flowering stage, which may contribute to higher biomass and glycoside concentrations through greater system productivity. Hitherto, there was no significant study about the effect of far-red LED induction to improve the steviol glycoside content of Stevia plants, particularly at the molecular level. This research was therefore performed in the TIS RITA ® bioreactor system to evaluate the effect of far-red LED induction towards biomass growth, multigene expression related to steviol glycosides, and its derivatives, and also the metabolites produced in S. rebaudiana plant. The result showed that the increment of biomass and gene expressions (ent-KO, ent-KS, ent-KAH13, UGT85C2, UGT74G1, and UGT76G1) in high far-red LED RITA ® was higher compared with control RITA ® . To conclude, the system with a far-red LED induction in TIS RITA ® was proven to give a positive effect towards stevia shoots growth and greater metabolites production (stevioside and rebaudioside-A) up to 37.15% and 22.99%, respectively.