I have just spent a week in Inner Mongolia province of China. As usual, I kept a lookout for interesting plants, but the plant diversity in Inner Mongolia is very low compared to Sichuan and Yunnan.
The most interesting find was the fruit of Physalis in a market stall. I think this must be Physalis alkekengi, the Chinese Lantern Plant. The fruit is an orange berry half the size of a cherry but completely covered by 5 expanded calyx lobes. There is a related weedy species in Malaysia, Physalis minima, locally known as letup-letup. Another species, Physalis peruviana, also known as the Cape Gooseberry, was introduced to Malaysia about ten years ago and is sometimes used in restaurants to decorate meat dishes. The fruits of all three species look very similar.
The fruits of P. minima and P. peruviana are both rather tasteless, but the fruits I found in China are as sweet as the sweetest grapes. It is also said to be a highly ornamental plant, with the calyces red in colour when fresh. P. alkekengi is perennial, surviving tbe cold winter by virtue of a resting underground stem. It may not thrive in the tropics. It would be interesting to hybridise it with P. minima to produce a sweet-fruited plant for the tropics.