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Descriptor: Spikelet fertility(pre-2007) (spkf_pre2007)

Spikelet fertility measurement is taken from counts of well developed fertile spikelets in proportion to total number of spikelets on five panicles at harvest. Observed in all species.
Post-harvest Stage
Crop Germplasm Committee approved
Data Type:
Alpha/numeric descriptor
Maximum Length:
Responsible Site:
International Rice Research Institute (IRRI)

Studies or environments

Distribution of Values for Spikelet fertility(pre-2007) (spkf_pre2007)

CodeDefinitionNumber of Accessions
1 Highly fertile12785
3 Fertile72661
5 Partly sterile12651
7 Highly sterile2169
9 Completely sterile89
999 Mixture12

International Rice Genebank Germplasm Distribution and Exchange Policy

IRRI continues the free international exchange of germplasm, in accordance with the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA). We provide rice in small quantities to any entity or establishment for research, breeding, or training for food and agriculture purposes; free of charge. At the same time, we gratefully receive seed contributions to add to our collection.

The procedure for acquiring seeds from IRRI are as follows:
1. Read, study and comply with Standard Material Transfer Agreement(SMTA).
2. Inquire, search and choose accessions through GRIN-Global or Genesys websites.
3. Submit requests electronically through the public websites (refer to #2)