Maïs Doux (Zea mays) — Plant Gene Profile | Zobium

Flavor & Sensory Profile

Dominant notes: sweet corn, grassy green, buttery, slightly nutty, light sulfurous.

Brix (typical): 18. Sweetness: high. Acidity: low.

Key Genes in Maïs Doux

• Sugary-1 (starch-branching enzyme) (su1) — Encodes a starch-debranching enzyme; loss-of-function converts starch to water-soluble polysaccharides (phytoglycogen), retaining sweetness in the kernel at harvest.: produces phytoglycogen, sucrose
• Sugary-Enhanced (se) modifier (se1) — Encodes a modifier locus that dramatically slows conversion of sugars to starch after harvest; heterozygous kernels reach 14–22% sugar, homozygous se+ kernels reach 22–35%.: produces sucrose, reducing sugars
• Lipoxygenase 10 (ZmLOX10) — Encodes a lipoxygenase enzyme that cleaves polyunsaturated fatty acids to produce C6 aldehydes and alcohols responsible for fresh-cut grassy aroma in sweet corn kernels.: produces n-hexanal, 1-octen-3-ol
• Phytoene synthase 1 (ZmPSY1) — Encodes the rate-limiting enzyme of carotenoid biosynthesis; controls yellow pigmentation of kernels by driving flux toward lutein and zeaxanthin in sweet corn endosperm.: produces lutein, zeaxanthin
• Carotenoid cleavage dioxygenase 1 (ZmCCD1) — Encodes a carotenoid-cleaving enzyme that converts carotenoids into C13 apocarotenoid volatiles, contributing to the characteristic sweet corn aroma including decylaldehyde and related aldehydes.: produces decylaldehyde, β-ionone
• Terpene synthase 1 (thiazole pathway) (ZmTPS1) — Encodes a terpene/heterocycle biosynthetic enzyme contributing to sulfur-containing volatile production; linked to the roasted-corn thiazole aroma compound 2-pentylthiazole.: produces 2-pentylthiazole
• Fruit/kernel weight QTL 2.2 (SlKGGF1 ortholog) (fw2.2) — Encodes a kernel size regulator; QTL alleles at this locus colocalize with kernel area and length QTL in maize-teosinte populations, influencing the plump, long-kernel phenotype of se varieties.: produces kernel cell expansion factor

Metabolic Pathways

• Sugar Retention Pathway — activity 75%: Primary driver of sweetness; su1 and se1 alleles together delay starch conversion, keeping kernels at 14–35% sugar depending on genotype
• Lipoxygenase / Green Aroma Pathway — activity 55%: Produces n-hexanal and 1-octen-3-ol — the grassy, fresh-cut and earthy mushroom notes that define raw sweet corn aroma
• Carotenoid & Kernel Colour Pathway — activity 60%: ZmPSY1 drives yellow kernel pigmentation (lutein, zeaxanthin); ZmCCD1 cleaves carotenoids into volatile aldehydes contributing waxy cooked-corn aroma
• Thiazole / Sulfur Volatile Pathway — activity 45%: Generates 2-pentylthiazole, the key compound responsible for roasted, cooked-corn aroma detected by GC-IMS
• Kernel Size & Ear Architecture — activity 60%: Controls kernel area and weight; larger, plumper kernels yield higher sugar-to-fibre ratio and more satisfying eating texture

Soil Microbiome Recommendations

• Rhizophagus irregularis — Improves phosphorus and zinc uptake, supporting the sugar-loading enzymes that keep se kernels sweeter at harvest.
• Azospirillum brasilense — Promotes deeper, denser root growth and supplements nitrogen supply, reducing the fertiliser needed while maintaining kernel sugar potential.
• Bacillus subtilis — Primes the plant's immune system against common sweet corn leaf diseases (northern leaf blight, grey leaf spot), reducing yield loss without fungicide residues.
• Trichoderma harzianum — Suppresses soilborne root rots (Fusarium, Pythium) and improves early root establishment, ensuring an even stand for consistent ear development.