title: Techniques for clearing ovules for studies of megagametophyte and early postfertilization development in Rhododendron.
abstract: Using ovule clearing, more than 33,600 ovules of Rhododendron nuttallii T. W. Booth (Ericaceae) were examined for megagametophyte and early postfertilization stages at daily intervals from anthesis until 3 weeks after pollination. Pretreatments with amyloglucosidase to digest integumentary and gametophyte starch and Stockwell's bleach to remove tannins from the integumentary epidermis were necessary. Ovules were cleared by a combination or modifications of Herr's four-and-a-half or Stelly's hemalum-methyl salicylate techniques and were observed using differential interference contrast optics. The method proved suitable for large-scale quantitative studies of ovule development and fertilization. A general protocol is suggested as a starting point for ovule clearing studies.
authors.affiliation: Department of Biological Sciences, Rutgers University, Piscataway, New Jersey 08855.
authors.forename: B F
authors.initials: BF
authors.lastname: Palser
authors.forename: J L
authors.initials: JL
authors.lastname: Rouse
authors.forename: E G
authors.initials: EG
authors.lastname: Williams
mesh_terms: D005306:Fertilization; D006652:Histological Techniques; D055095:Optics and Photonics; D059828:Plant Cells; D018521:Plant Physiological Phenomena; D013194:Staining and Labeling / Q000379:methods