Well the bicolor sorghum has 2 names :
Japanese : Takakibi タカキビ（高黍）
Chinese : Kaoliang 高粱
That’s the same grain. I believed they were a different plant…
If you see the same Chinese characters, clean your glasses, the second is different…, yes, they probably used to be similar and were changed. Now both can be seen in Japanese books…
The “white” is the kaoliang and the “red” the takakibi. Yes, both where totally red and the kaoliang is more polished, but look at shape and size… as different as Uncle Ben’s and Thai jasmine rice. So variation in sorghum is as wide as that in rice…
Taste ? A little different too, but that’s not food with huge flavor. I prefer the Japanese one.
There is a difference of price too. 20. Not 20 yen per kilogramme.
I paid about the same price for both, I had 50 g in the enveloppe of takakibi-sorghum, and 1 kg in the bag of kaoliang-sorghum. LOL.
I was lost with terms… for a second reason. Sorghum is also called “morokoshi” (sorghum) in Japanese, I mean in books, not where I shop. The maize corn was later named “to-morokoshi” (Tang sorghum… ). But that was much later than Tang era, that’s because ….. my Chinese teacher explained when I was not listening, oh no, I always listen, she explained in Chinese, so sorry, I need to take more Chinese lessons to tell you.
Oh, that’s not worse than the corn/corn confusion in English.
Takakibi sorghum with white rice, here.