Genomic polymorphism in consecutive generation rice plants from seeds on board a spaceship and their relationship with space HZE particles

Abstract

Dry rice seeds (Oryza sativa, subspecies indica) were sandwiched between nuclear track detectors, aboard the Chinese spaceship Shenzhou-3 for seven days. The seeds were recovered and the genomic polymorphism in 201 plants developed from these seeds was studied using random amplified polymorphism DNA analysis. When compared with plants from ground-based control seeds, the genomic polymorphic bands were amplified in 30.2% of the plants from the seeds exposed in space. The results for sequencing and SNP analyses of the polymorphic bands verified the single nucleotide variations in these plants. Genomic polymorphisms in the consecutive generations of individual plants of the seeds from space were also discovered. Seven seeds receiving hits of HZE (high atomic number and high energy) particles from space were selected for further analyses and variable genomic polymorphisms were detected in all plants that developed from these seeds. Among them, the embryos of three seeds were hit at least once, and mutants with significant changes in agronomic traits were only found in later generations of these seeds. This result implies that the HZE particles of space are effective in inducing the changes of plant genome of inherited phenotypes.