Germination studies of the pollen grains of a Scrophulariaceae plant, Torenia asiatica Linn. have revealed that the maximum percentage of germination and longer tubes were attained in 15 percent sucrose solution. Among the chemicals tried, calcium and boron enhanced germination. Less germination occurred among grains treated with potassium or magnesium salts. Abnormalities such as branched tubes with or without vesicles were found in chemically treated pollen grains.
Nambudiri, E. M. V. and Thomas, M. K.
"Effects of chemicals on the germination of pollen grains of Torenia asiatica Linn,"
Great Basin Naturalist: Vol. 34
, Article 5.
Available at: https://scholarsarchive.byu.edu/gbn/vol34/iss1/5