1. A genetic study of unilateral incompatibility between diploid (1EBN) Mexican species Solanum pinnatisectum and S. cardiophyllum subsp. cardiophyllum

   • Joseph C. Kuhl
   • Michael J. Havey
   • Robert E. Hanneman

   Original Article Pages: 305 - 313

2. Pollen UDP-glucose pyrophosphorylase showing polymorphism well-correlated to the S genotype of Pyrus pyrifolia

   • Daiji Kiyozumi
   • Takeshi Ishimizu
   • Shigemi Norioka

   Original Article Pages: 315 - 323

3. Developmental expression of polyubiquitin genes and distribution of ubiquitinated proteins in generative and sperm cells

   • Mohan B. Singh
   • Huiling Xu
   • Scott D. Russell

   Original Article Pages: 325 - 329

4. Changes of calcium distribution in egg cells, zygotes and two-celled proembryos of rice (Oryza sativa L.)

   • J. Zhao
   • F. Yu
   • H. Yang

   Original Article Pages: 331 - 337

5. Isolation and characterization of male-germ-cell transcripts in Nicotiana tabacum

   • Hengping Xu
   • Koen Weterings
   • Celestina Mariani

   Original Article Pages: 339 - 346

6. Variability of pollen grain features: a plant strategy to maximize reproductive fitness in two species of Dianthus?

   • Tejaswini

   Original Article Pages: 347 - 353

7. The Arabidopsis MEI1 gene likely encodes a protein with BRCT domains

   • Ming Yang
   • Sheila McCormick

   Short Communication Pages: 355 - 357