The study looked at wheat production in China to see how much wheat farmers could potentially yield compared to what they actually yield. They found that the best farmers in China could produce 9.0 tons of wheat per hectare, but on average, farmers only produced 5.6 tons. This means there is a gap of 3.4 tons between what is possible and what is actually being achieved. Factors like water availability, climate, and farming practices all play a role in this difference. Overall, there is a lot of potential to improve wheat production in China, with different regions having different advantages for growing wheat.