Fig 1.
Solar radiation (Wm-2) reading based on sampling time, collected from Dusun Durian, Selangor.
Fig 2.
Diurnal trend and comparison of A) sucrose and sugar phosphates, B) total amino acids, and C) nucleotides that showed higher concentration in HY palm throughout the circadian cycle. Green bar represents the average of HY (n = 10); Red bar represents the average of LY (n = 10) collected in the open field. The concentration of metabolites was quantified by relative abundance to the internal standard, Ribitol (2 mg mL-1). * represents a significant difference between HY and LY with p-value ≤ 0.10. The concentration of metabolites was quantified by relative abundance compared to the internal standard, Ribitol (2 mg mL-1).
Fig 3.
Differentially expressed genes (DEGs) comparison analysis of all 5 time points.
Q value ≥ 0.8. D1_07:00, D2_11:00, D1_15:00 and D1_19:00 are the sampling time points within the same day. D2_07:00 is the sampling time point the next day. The numbers in the diagram indicate the total number of transcripts in that cluster. The annotation of the transcript/s within a cluster are listed in S6 Table.
Table 1.
GO enrichment analysis of all differentially expressed genes in high- and low-yielding oil palms.
Cut off threshold, p-value ≤ 0.05. Ticks indicate the presence of GO terms in specific time point.
Fig 4.
Differential expression of three photosynthesis related genes, Photosystem I (PSI), Chlorophyll a-b binding protein 13 (CAB-13) and Ferredoxin- NADP reductase (FNR) in HY and LY palms (n = 20) using RNAseq.
* Significant differences between HY and LY oil palm Log2 ratio ≥ 2, Q ≥ 0.80 is explained by the probability of equivalent expression in Noiseq [31]. Blue line represents the expression of PSI, black CAB-13, red FNR.
Table 2.
Pathways enrichment analysis of all differentially expressed genes in high-yielding oil palms.
Cut off threshold, p-value ≤ 0.05. Ticks indicate the enriched pathway in specific time point.
Fig 5.
Diurnal changes on (A) photosynthetically active radiation, PAR, (B) leaf temperature, T, (C) net photosynthesis, A, (D) leaf air vapour pressure deficit, VPD, (E) relative humidity, RH, (F) internal CO2 concentration, Ci, (G) transpiration rate, E and (H) stomatal conductance, gs of oil palms measured in field. Green bar represents the average of HY (n = 5); Red bar represents the average of LY (n = 5); * represents a significant difference between HY and LY with p-value ≤ 0.05. ** represents a significant difference between HY and LY with p-value ≤ 0.10.
Fig 6.
Differential photosynthesis gene expressions, gas exchange and the Calvin cycle in HY and LY oil palm leaves.
Green bar represents the average of HY (n = 5 for gas exchange; n = 10 for metabolites and expressions); Red bar—the average of LY (n = 5 for gas exchange; n = 10 for metabolites and expressions) collected in the open field. * represent a significant difference between HY and LY with p-value ≤ 0.05; The concentration of metabolites was quantified by abundance relative to the internal standard, Ribitol (2 mg mL-1).