Modifications of Leaf Morphogenesis Induced by Inhibition of Auxin Polar Transport

Abstract

Auxin is an unique hormone with polar transport among those well-known plant hormones. It has been shown that auxin polar transport plays an important role in a number of physiological process (such as gravitropism, phototropism, early development of floral bud formation, etc.) (Goldsmith, 1977; Okada et al, 1991). Our previous work (Liu et al, 1993) already demonstrated that auxin polar transport is essential for establishment of bilateral symmetry in early development of zygotic embryos. In Brassica juncea, auxin polar transport inhibitors induced the formation of a collar cotyledon, instead of two opposite cotyledons on the globular embryos cultured. The fused cotyledon also was observed in Arabidopsis mutant pin-1 with impaired auxin polar transport (Liu et al, 1993). The present study aims at revealing whether it also affects pattern formation of leaf morphogenesis in shoot formation from leaf explants cultured and sterile seedlings.