Abstract: Potassium antimonite was used to locate loosely bound calcium in the stigma, style and pollen tubes of Torennia fournieri. During pollen germination and tube elongation, the pollen tube wall is densely labeled with calcium precipitates. Calcium precipitates accumulate in the pollen tube, increase in stylar tissue at first and decrease later. When pollen tubes enter into the ovary, there are numerous calcium granules in ovary locule and less in the pollen tube. Calcium gradient exists in in vivo pollen tube of Torenia fournieri and becomes evident along with growth of pollen tube. There is evident calcium gradient in the style of Torennia fournieri before pollination and abundant calcium in the area where pollen tube arrived. It is concluded that there are enough calcium in pollen of Torenia fournieri to supply pollen germination, calcium flows into pollen tube from stylar tissue continuously in order to supply the growth of pollen tube, a higher calcium environment is helpful to pollen tube into the micropyle when pollen tubes grow in ovary locule, the gradient distribution of calcium in the style tissues play a guiding role to the growth of pollen tubes. 

Key words: Torenia fournieri, calcium, pollen tube, stigma, style