Revitalizing breeders' seed production : the essential source of quality seeds

The Plant Breeding, Genetics and Biotechnology Division of the International Rice Research Institute (IRRI) centralized the different steps in rice breeding through the establishment of cross-cutting groups such as the Breeder Seed Production Team. The objective of this team is to multiply and purify newly released varieties, popular varieties, and promising lines for sharing with IRRI, partner institutions, and farmers. The Bureau of Plant Industry-National Seed Quality Control Services (BPI-NSQCS) conducts a series of field inspections and seed tests to ensure that the seeds produced are pure and of high quality. Stringent agronomic practices, head rowing, intensive rouging, and proper postharvest practices, are needed to pass certification standards. Since 2013, 43 seed lots have been submitted to BPI-NSQCS. Seed lots that have passed certification were classified into 3 breeder seeds, 9 foundation seeds, 10 registered seeds, and 14 certified seeds. Rejection of seed lots may occur because of impurities or low germination. Improving the practices in seed production is necessary to be able to consistently produce breeder seeds. The effectiveness of molecular marker techniques, particularly single nucleotide polymorphism (SNP) genotyping and random amplified polymorphic DNA (RAPD) genotyping, in identifying off-types is currently being evaluated. In the 2014, wet season, 10 phenotypically similar plants each from 23 entries in breeder seed production plots were sampled at the vegetative stage. SNP genotyping was performed by the IRRI's Genotyping Services Laboratory Plants that were shown to be genotypically different from the rest of the samples of that variety were found to be off-types at maturity. Thus, off-types could be identified and roughed as early as the vegetative stage. RAPD genotyping using the same plants is currently being done and the results will be compared from that of SNP genotyping. If the results are comparable, RAPD genotyping could be a cheaper alternative to SNP genotyping.