Inter-family distant hybridization of Oryza sativa and Oenothera biennis

Progenies derived from rice ( Oryza sativa ssp. japonica ) plants pollinated by Oenothera biennis exhibited numerous morphological and developmental traits. Some variant individuals appeared in generation D2. From generations D3 to D6, a large number of variants were observed, showing distinct variable traits including giant embryos. Statistical analysis on D6 lines showed significant differences between progenies and their rice parental line in several main traits, including plant height (49.2–164.5 cm), panicle number (12.1–38.2), panicle length (20.3–30.3 cm), length of sword leaf (13.8–57.5 cm), leaf width (11.1–25.2 mm), grain number of main panicle (142.0–367.0), percentage of seed setting (0.8–99.0%), 1000-grain weight (19.7–33.8 g) and time from germination to panicle emergence (90.0–108.0 days). Most of the variable coefficients were above 20% (the highest was 40.8%). Through pedigree selection of these plants, genetically stable lines were obtained, which are useful for rice breeding. Results from amplified fragment length polymorphism (AFLP) analysis showed that several rice lines contained extensive genetic variations, which included disappearance of rice parental bands and/or appearance of novel bands.