title: Male gametogenesis and sterility in garlic (Allium sativum L.): barriers on the way to fertilization and seed production.
abstract: Commercial cultivars of garlic (Allium sativum) do not produce flowers and seed; hence, information on microgametogenesis and genetic knowledge of this important crop is unavailable. Recently, physiological studies enabled flowering and fertility restoration in garlic bolting genotypes by environmental manipulations, thus broadening of the genetic variation and facilitating genetic studies. The present report provides first detailed description of the development of male gametophytes in 11 garlic genotypes varying in their fertility traits. Morphological and anatomical studies revealed completely fertile genotypes, as well as variation in anther and pollen development and disruption of the male organs and gametes at different developmental stages. Three types of plant sterility were observed, including complete sterility, male sterility and environmentally induced male sterility. The ITS1 and ITS2 regions of rRNA of the studied genotypes proved to be strongly conservative and thus did not correspond with the phenotypic expression of fertility or sterility in garlic. On the other hand, two-dimensional protein separation maps revealed significant differences between fertile and sterile genotypes, as well as between developmental stages of microsporogenesis. Further research is needed to investigate the internal mechanisms and environmental component of garlic sterility, as well as the possible molecular markers of these traits.
authors.affiliation: The Robert H. Smith Institute of Plant Science and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
authors.forename: Einat
authors.initials: E
authors.lastname: Shemesh Mayer
authors.forename: Krystyna
authors.initials: K
authors.lastname: Winiarczyk
authors.forename: Lidia
authors.initials: L
authors.lastname: Błaszczyk
authors.forename: Arkadiusz
authors.initials: A
authors.lastname: Kosmala
authors.forename: Haim D
authors.initials: HD
authors.lastname: Rabinowitch
authors.forename: Rina
authors.initials: R
authors.lastname: Kamenetsky
mesh_terms: D001483:Base Sequence; D018744:DNA, Plant / Q000145:classification / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000145:classification / Q000235:genetics; D015180:Electrophoresis, Gel, Two-Dimensional; D005737:Garlic / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development; D014644:Genetic Variation; D005838:Genotype; D056626:Inflorescence / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development; D008969:Molecular Sequence Data; D010641:Phenotype; D010802:Phylogeny; D051479:Plant Infertility / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011058:Pollen / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development; D012639:Seeds / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development; D012689:Sequence Homology, Nucleic Acid; D013696:Temperature; D013997:Time Factors
chemical_list: D018744:DNA, Plant; D021903:DNA, Ribosomal Spacer; D010940:Plant Proteins