Crop biotech · Bioecon

Thirteen subjects that look like a list of separate techniques — speed breeding, grafting, nitrogen fixation, ornamentals — but keep returning to the same three statements.

Almost everything a variety is bought for is polygenic. That is why the workhorse of this cluster is prediction: the most powerful breeding tool ranks plants by genes it never identifies, and editing, excellent at breaking a single gene, is poor at building yield. The limiting step has moved to the field. Sequencing became cheap and measuring plants did not, so the bottleneck sits in phenotyping and in the generations per year that extended daylength buys — generations, not better decisions about which plants to keep. Every trait is a trade-off stated as arithmetic. A perennial cannot put everything into seed; drought tolerance usually costs yield when the rain arrives; nitrogenase is destroyed by the oxygen a leaf cannot stop making.

Start with genetic engineering and breeding: it sets out the polygenic logic that the other pages either exploit or collide with. The method pages — phenomics, speed breeding, CRISPR — follow from it; nitrogen fixation and perennial grains are the hard unsolved cases.

Allelopathic crops Benzoxazinoids and sorgoleone are genuine root-released herbicides. What limits them is not potency but dose at the target, soil persistence and the crop's tendency to poison itself.
Biofortification of crops Why phytate, provitamin A conversion and the food matrix decide whether a biofortified crop changes anyone's nutritional status — and why Golden Rice stalled for reasons that were never biochemical.
Climate-resilient crops Stomatal control, rooting depth, osmotic adjustment and ABA signalling are separate strategies with separate costs. Why greenhouse results overstate field performance, and why heat damage is concentrated in a few days of flowering.
Genetic design of ornamental and landscape plants Anthocyanin chemistry, vacuolar pH and the fungal luciferin cycle explain what has actually been achieved in engineered ornamentals — and why a glowing plant is not a light source.
Genetic engineering and breeding Additive variance, the breeder's equation and genomic selection: why marker-assisted selection failed for yield, what genomic prediction actually does, and where single-gene engineering fits.
Vegetable grafting platforms How a graft union forms, why a rootstock confers soilborne disease resistance and vigour without altering the scion genome, and what graft incompatibility actually is.
Closed-loop food systems for Mars Mass closure, equivalent system mass, harvest index and the light-energy cost of calories — the real constraints on growing food in a sealed habitat, and what the closed-system experiments actually showed.
Nitrogen-fixing cereals Why nitrogenase is incompatible with an aerobic cell, what a legume nodule actually costs, and why associative diazotrophs — which fix far less — are the only route currently working in a cereal.
Nitrogen-fixing microbial inoculants Flavonoid and Nod factor signalling, why host specificity is chemical, and why nodulation competitiveness rather than survival is the failure mode particular to legume inoculants.
Perennial grains The allocation trade-off between perennation and grain yield, where Kernza actually stands against annual wheat, and why perennial rice is the informative exception.
Phenomics and high-throughput phenotyping Why phenotyping is the binding constraint on genomic selection, what a sensor actually measures as opposed to what the trait is, and how field spatial variability is handled.
Precision plant breeding with CRISPR Why loss-of-function targets suit CRISPR and polygenic traits do not, what base and prime editing add, and why transformation and regeneration remain the bottleneck that morphogenic regulators address.
Speed breeding and seed services How photoperiod extension and early harvest compress a breeding cycle, which crops it suits, and why it attacks only one term of the breeder's equation.