Oryza nivara Oryza nivara Oryza nivara is a wild progenitor of the cultivated rice "Oryza sativa". It is found growing in swampy areas, at edge of pond and tanks, beside streams, in ditches, in or around rice fields. Grows in shallow water up to 0.3 m, in seasonally dry and open habitats. It is an annual, short to intermediate height (usually <2 m) grass; panicles usually compact, rarely open; spikelets large, 6-10.4 mm long and 1.9-3.4 mm wide, with strong awn (4–10 cm long); anthers 1.5–3 mm long. Its distribution includes Bangladesh, Cambodia, China, India, Laos, Malaysia, Myanmar, Nepal, Sri Lanka, Thailand,
Helitron (biology) Helitron (biology) Helitrons are one of the three groups of eukaryotic class 2 transposable elements (TEs) so far described. They are the eukaryotic rolling-circle transposable elements which are hypothesized to transpose by a rolling circle replication mechanism via a single-stranded DNA intermediate. They were first discovered in plants ("Arabidopsis thaliana" and "Oryza sativa") and in the nematode "Caenorhabditis elegans", and now they have been identified in a diverse range of species, from protists to mammals. Helitrons make up a substantial fraction of many genomes where non-autonomous elements frequently outnumber the putative autonomous partner. Helitrons seem to have a major role