GUIYANG, July 3 (Xinhua) -- Chinese researchers have cultivated new varieties of rosa roxburghii from 528 plantlets growing from 28yellowbass.2 grams of seeds that had been aboard the Shenzhou-15 manned spaceship in space for 186 days.

Rosa roxburghii, or Cili, meaning "thorn pear" in Chinese, is a yellowish, spiny fruit renowned for its rich vitamin C content and various nutritional benefits.

For the first time, researchers obtained four plantlets with distinctive shapes, two of which are thorn-free and have markedly different leaf shapes compared with typical thorn pears, according to local authorities in Qiannan Buyi and Miao Autonomous Prefecture, southwest China's Guizhou Province.

The acquisition of new germplasm is of great value to the selection and breeding of thorn-free pear varieties. To shorten the breeding process, researchers are adopting certain methods to reproduce the plantlets while carrying out tissue culture experiments on thorn-free varieties, said researcher Tian Hualin.

This new batch of germplasm will be included in the local thorn pear germplasm bank. A space breeding base of thorn pears will be established to promote the innovation of its germplasm resources.■