That betrays a basic misunderstanding of both economics and China. Firstly, rice is the staple food of _southern_ China; northern Chinese eat wheat noodles and buns as stables. Secondly, China is developed enough now that the average person is not so poor that they couldn't afford to feed themselves enough non-rice food to avoid starvation for the 6-12 months necessary for the rice to be replaced with a different crop (and for the truly poor, the government could just ration the wheat).
Look at it another way: wheat is the staple food of western countries, but how many westerners would starve to death if all the wheat products suddenly disappeared from stores? Very few, given the ample supply of rice, corn, potato and dairy-based alternatives.
Look at it another way: wheat is the staple food of western countries, but how many westerners would starve to death if all the wheat products suddenly disappeared from stores? Very few, given the ample supply of rice, corn, potato and dairy-based alternatives.