Oryza longistaminata

Why are the seeds of this species difficult? Some species of the Poaceae family can produce a high proportion of empty seeds, which collectors and curators must take account of. The seeds may have physiological dormancy, which can be overcome by mimicking the seasonal patterns of the species' native habitat.

Oryza longistaminata (Image: S. Wood, RBG Kew)

Seed Storage

This species most probably has Orthodox seeds - dry to 15-20% eRH and store at -20ºC, or as cool as possible.

Germination Requirements

Remove the seed covering structures before placing the seeds under germination conditions. Germinate on agar, germination paper or sand at 25ºC. Perform a cut-test on any seeds that have not germinated, to check for empty seeds. All empty seeds are non-viable in germination tests.

The seeds of this species may be Physiologically Dormant (based on other species in the same genus). If germination is low, this type of seed dormancy can be overcome by mimicking the seasonal patterns of the species' native habitat. Use a moist pre-chill or pre-heat treatment (depending on local climatic conditions) or a dry after-ripening treatment, before germinating the seeds on agar, germination paper or sand at their optimum temperature. If this does not work, you can perform delicate surgery to enable the embryo to grow. Excise the tissue near the root tip.

Seed Morphology

Oryza longistaminata
(Image: S. Wood, RBG Kew)

The occurrence of empty seeds is common in wild-collected accessions of some Poaceae species. Empty seeds may have a normal seed coat but an absent or under-developed embryo, or limited storage tissue.

See more images of this species at the Digital Atlas of Economic Plants.

Taxonomy

Family: POACEAE

Accepted name: Oryza longistaminata A.Chev. & Roehrich

Synonyms: Oryza silvestris Stapf ex A.Chev.

Common name:

References and Links

Black, M., Bewley, J.D. and Halmer, P. (2006). The Encyclopaedia of Seeds: science, technology and uses. CAB International, UK.
Food and Agriculture Organization of the United Nations and International Plant Genetic Resources Institute (1994). Genebank Standards. FAO/IPGRI, Rome, Italy.

AFPD (African Flowering Plants Database) - Conservatoire et Jardin Botaniques de la Ville de Genève, Switzerland, and South African National Biodiversity Institute, Pretoria, RSA: Oryza longistaminata.
PROTAbase (Plant Resources of Tropical Africa) - Wageningen, Netherlands: Oryza longistaminata.
SID (Seed Information Database) - Royal Botanic Gardens, Kew, UK: Oryza longistaminata.
Tropicos - Missouri Botanical Garden, USA: Oryza longistaminata.