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Hevea brasiliensis, a natural rubber producing species, is widely cultivated due to its high rubber yield potential. Natural rubber is synthesised in the rubber particles of laticifers. Latex diagnosis (LD) was established to characterise the physiological state of the laticiferous system by measuring its physiological parameters, i.e., sucrose, inorganic phosphorous (Pi), thiols and total solid content (TSC). Rubber clones are often classified in three groups i.e., quick starters, medium starters and slow starters. To better understand the genetic bases of latex yield, a biparental population was generated from a cross between the quick-starter clone PB 260 and the medium-starter clone SP 217. LD was performed during the peak latex production season and used to calculate sucrose loading. The agronomic and physiological parameters associated with latex yield led to the classification of genotypes according to the rubber clonal typology and to the identification of quantitative trait loci (QTL) using a high-density map. Inorganic phosphorous content was positively associated with yield during the first year of production thus enabling identification of quick-starter clones. In addition, the LD-based clonal typology led to determine the long-term yield potential and the use of appropriate ethephon stimulation. QTL analysis successfully identified several QTLs related to yield, sucrose, Pi and TSC. One QTL related to sucrose loading was identified in the same position as the QTL for sucrose on linkage group 1. To our knowledge, this is the first study to report QTL analysis for this trait. The use of a high-density map enables the identification of genes underlying QTLs. Several putative genes underlying QTLs related to yield, sucrose and TSC were identified.

Latex diagnosis (LD) is applied to optimize the natural rubber production and prevent tapping panel dryness (TPD), a physiological syndrome affecting latex production in Hevea brasiliensis. The reduced thiol content (RSH) is one of the biochemical parameters associated with the risk of TPD. However, RSH is difficult to interpret because of the influence of the environment. In order to better understand the regulation of antioxidants and to better interpret RSH, a key parameter of LD, this study analysed in latex both oxidised and reduced forms of ascorbic acid (AsA) and glutathione, and their cofactors as well as other latex diagnosis parameters in response to harvesting stress (tapping and ethephon stimulation) and TPD occurrence. The content of antioxidants in latex had a high variability among five rubber clones. The concentration in AsA was about ten times higher than GSH in laticifer, GSH accounting for about 50% of RSH. For short-term harvesting stress, RSH increased with tapping frequency and ethephon stimulation. TPD is associated with high latex viscosity and bursting of lysosomal particles called lutoids, as well as for several rubber clones with lower RSH and GSH contents. These results suggest that a high level of RSH shows the capacity of laticifer metabolism to cope with harvesting stress, while a drop in RSH is the sign of long stress related to lower metabolic activity and TPD occurrence. RSH remains an essential physiological parameter to prevent TPD when associated with reference data under low and high harvesting stress. This study paves the way to understand the role of AsA and GSH, and carry out genetic studies of antioxidants.

Tea Mosquito Bug (TMB), Helopeltis bradyi (Hemiptera: Miridae) is one of the major pest infesting tea and cocoa plantations worldwide. Developing olfaction-based control methods was urges as an alternative to commonly used but non-environmental friendly chemical pesticides. However, the molecular mechanisms underlying TMB reception mechanism are still lacking. Here, we collected a pooled male and female TMB antennae for RNA extraction followed by sequencing using the BGISEQ-500 platform and de novo assembly. TMB antennae RNA-seq data yielded 32,142 unigenes with N50 and GC (%) were 2322 and 40.25; subsequently. The RNA-seq data are available in GenBank Sequence Read Archive (SRA) database with accession number SRR13327229. De novo transcriptome analysis had identified several genes involved in TMB odorant reception includes; 39 OBPs (odorant binding proteins), 10 CSPs (chemosensory proteins), 81 Ors (odorant receptors), 1 Orcos (co-receptors), 9 SNMPs (sensory neuron membrane proteins), 3 GRs (gustatory receptors) and 4 IRs (ionotropic receptors). Our study presents the first RNA seq for TMB antennae, which serve the primary molecular resources data, which will facilitate further research to develop olfaction-based control methods, potentially contribute to TMB management strategies.

Blood disease of Banana (BDB) is one of the prevalent disease caused by Ralstonia syzygii subsp. celebesensis (Rsc) which cause substantial loss on banana production in Indonesia. To date, the genetic basis of plant defense mechanism caused by blood disease in banana is not available. As a matter of fact, the knowledge of global gene expression will provide important information on plant response to the pathogen infection. Data from transcriptomic analysis in response to blood disease infection from Musa acuminata cv. Mas Kirana (AA group), representing the A genome, and Musa balbisiana cv. Klutuk (BB group), representing the B genome, were firstly reported. The transcriptome data discussed in this publication are accessible through NCBI's Gene Expression Omnibus with GEO Series accession number GSE138749. These data provide the basis for further investigation on the global gene expression which is pivotal to understand the mechanism of disease resistance from two banana genomes in response to blood disease infection. Keywords: Defense mechanism, Disease resistance, Gene expression, Pathogen, RNA-seq

The increasing production of banana is hampered by the spread of banana plant diseases, one of which is caused by a group of bacteria, including those of causing wilt diseases. In Indonesia, blood disease is one of the important banana wilt diseases since loss due to the infection can reach up to 50%. There are numerous publications on the pathogen identification causing banana blood disease based on the molecular approach, however to date, no detailed molecular data are available for the interaction of banana host plant against the pathogen. Here, we present three raw data sets of the total RNA-seq from the inoculated Musa balbisiana cutivar kepok (ABB genome) inoculated with Ralstonia syzigii subsp. celebesensis, Ralstonia solanacearum and mock. The data provide essential knowledge for differentiating the banana response against pathogen, reveal pathogenesis-related genes and gene functions in the plant system, and research development to design blood disease-resistance of banana as one of the management strategies. Raw reads of RNA-seq data can be found in NCBI's Sequence Read Archive (SRA) database with the accession number of SRR10547839 (RSC), SRR10547840 (RS), and SRR10547841 (Mock). Keywords: Banana, Leaf, Inoculated, Ralstonia syzygii subsp. celebesensis, Ralstonia solanacearum, Transcriptome