## 2 Results
### Gene Expression Levels of AsA Biosynthetic Pathways Concerning Tissue Development  
The expression analyses of genes evaluated during the development of leaves, cotyledons, and seeds are shown in Figures 5 and 6. In leaves (Figure 5A), several genes encompassing three AsA biosynthesis pathways were highly expressed at stage 1 (V3 stage) compared to young leaves (bioproject PRJNA631275), but the transcript levels of the majority of genes decreased during the leaf senescence period (stages 3 to 8 compared with stage 1). Among the D-mannose/L-galactose pathway-associated genes, all _GMP_, _GME_ (except _GME_1b_), and _GGP_ gene members, as well as _GPP_1_ and _GPP_2_, showed increased transcript levels. In contrast, the genes linked to the two last steps of the pathway, _GalDH_ (_Ia_ and _1b_) and _GalLDH_ (_Ia_ and _1b_), did not show significant changes (Supplementary Table S5) at stage 1 (V3 stage). As for leaf senescence (stages 3 to 8 compared to stage 1) (bioproject PRJNA262564), only _GMP_alpha_C_ and _GGP_1a_ were found to be induced. Remarkably, while _GalDH_ (_Ia_ and _1b_) expression significantly decreased, _GalLDH_ (_Ia_ and _1b_) did not change during leaf senescence (Figure 5 and 6, Supplementary Table S5). For the guilde pathway, _GULO_1c_ mRNA levels increased only at stage 1 (V3) and, together with _GULO_1d_, _1e_, and _1f_, reduced with leaf age and were minimally detected from leaf stages 3 to 8 (Supplementary Table S5). In addition, although _GULO_3_ was expressed across the time points, its expression was reduced during leaf senescence (stages 3 to 8). However, the _GULO_1f_ and _1g_ transcript levels increased across the leaf stages (5 to 8). For the galacturonate pathway, only _GalUR_4_ mRNA levels increased at leaf stage 1 (V3 stage), and _GalUR_2_, \(4\), and \(5\) expression increased in the leaf from stage 7 to 8. Last, for the Myo-inositol pathway, gene expression did not appear to be stimulated in leaves at the vegetative stage (compared to young leaves). _MIOX_2a_ was the mainly expressed gene in leaves, but its expression decreased drastically from leaf stages 3 to 8. _MIOX_1a_ and _1b_ were expressed in young leaves, but their expression decreased at stage 1 and then increased at stage 8. Other genes from this pathway were barely detected. Overall, these expression levels were found to be significant at \(p\) < 0.05 (Supplementary Table S5). Concerning cotyledons (Figure 5B), gene expression was evaluated at 15 and 27 DAG (days after germination) in comparison to the first time point (4_DAG). In parallel to leaf aging, some genes presented similar expression profiles in cotyledons, but some differences were observed. For instance, similar to leaves, mRNA levels of _GMP_alpha_A_ and _alpha_B_, _GPP_1a_ and _1b_, _GalDH_1a_, _GME_1a_ and _1b_, _GULO_1b_ and _1c_, _and_ _MIOX_2a_ decreased, while _GMP_alpha_C_, _GULO_1f_, and _GalUR_4_ transcript levels increased. However, cotyledons showed a different profile compared to leaves, mainly in terms of the induced transcript levels of all the _GGP_ gene members, including _MIOX_1a_, _1b_, _2b_, _3a_, and _GULO_3_. In addition, _GULO_1a_, _1d_, _1e_, _1g_, _and_ _MIOX3b_ were scarcely detected or not detected in cotyledons. Generally, these expression levels were significant at \(p\) < 0.05 (Supplementary Table S5). For seed development (Figure 6; stages 2 to 5 in comparison to stage 1), comparative analyses of the four experimental genotypes (3 mlpa, 3 MWT, 1 mlpa, and 1 MWT) revealed some differences. However, a similar expression profile among genotypes was observed with increased transcript levels of _GalUR_1_, 2, and \(5\), _GGP_1a_, _GPP_2, and _GME_1a_ (first stages) and with decreased mRNA levels of _GGP_1 likeA_ and _1 likeB_, _GPP_1, _GME_1b_ and 2b, and _MOX_1b_ and _2b_. Overall, these data were significant at \(p\) < 0.05 (Supplementary Table S5).