Photoautotrophic Growth of Tube-plantlets Derived from Elite Autotetraploid Rice Individuals of Hybrid Progenies under Open Condition Selection of Primary Trisomics from Anther Culture of Autotetraploid Rice (Oryza sativa L.) DEVELOPMENT AND CHARACTER OBSERVATION OF AUTOTETRAPLOID POLYEMBRYONIC MUTANT RICE INDUCED BY ION BEAM IMPLANTATIOON Inheritance of Aroma in Autotetraploid and Diploid Rices Rice Tetraploidy and Its Effect on Agronomic Traits and Nutritional Constituents Structure and Fertilization of Embryo Sac in Intersubspecific Hybrids of Autotetraploid Rice Cytological Observation on Microsporogenesis in Inter-subspecific Hybrids of Rice with Different Ploidy Level Chromosome Pairing Behavior and Reproduction in the Hybrid Developed by the Interaction of Different Pollen Sterile Genes in Autotetraploid Rice