Creating &quot;much bigger seed heads&quot; is one of those things that sounds much easier than it is. For one, grain crops like wheat have pretty much approached the limit of what&#x27;s called &quot;harvest index&quot; -- the ratio of the seed head to the rest of the plant in terms of biomass. Any further and the seed head becomes to heavy to support and the plants fall over before harvest.<p>But more importantly, things like this come down to the difference between qualitative traits(traits like those in Mendel&#x27;s peas, where a single or a couple genes control the trait and it&#x27;s inherited in a mendelian fashion) versus quantitative traits(traits controlled by many genes, like skin color in humans, where the distribution of traits within a population takes the form of a bell curve). Glyphosate works by inhibiting the action of a single enzyme, so a single gene coded to produce a variant of the enzyme resistant to the chemical, or an enzyme that can degrade glyphosate, can confer resistance. The yield of a plant and how it distributes its resources however are hugely complex traits that not only involve essentially every gene in the plant in some way, but also environmental factors. It&#x27;s still simply more effective to use traditional methods, crossing different plants and performing multiple rounds of selection based on yield, than it is to use biotechnology.