Abstract: A male sterile germplasm JXB-1 was discovered at three-year-old wild Platycodon grandiflorum germplasms area in Longjing city in 2006 and its development and reproduction were further studied. The results showed that there was no obvious difference in flower’s outward appearance between JXB-1 and normal plant, but JXB-1 had shriveled and cracked anther with no microspore, forced anther with irregular and no activities, its self-pollination rate was zero and crosspollination rate was 100%. Anther and microsporogenesis observations showed that JXB-1 anther abortion mainly took place at tetrad stage because small spore growth was stopped for tapetum cells premature disintegration. Vegetative propagations of tissue culture for JXB-1 was all male sterile. It was preliminarily shown that JXB-1 was a male sterility germplasm, had high affinity with other germplasms and can be used as fine breeding material.

Key words: Platycodon grandiflorum, male sterility, germplasm, development and reproduction