Chemical Control of Morphogenesis in Moss Protonema

The protonema of the moss, Funaria hygrometrica, grows continuously in calcium-free liquid media. The growth was promoted by addition of oxalate, although the morphogenesis resulting in formation of gametophytic buds on the protonema was suppressed by the addition. Calcium oxalate promoted the growth of protonema, while at a high concentration (10−2 M) it caused the formation of clumped protonema (falsebuds). Addition of plant growth hormones, such as IAA, NAA, 2,4-D and gibberellin retarded the growth of protonema, while 2,4-D at a low concentration stimulated the growth of protonema. Kinetin greatly stimulated the formation of gametophytic buds in the protonema, but these buds were found to be morphologically and physiologically abnormal.