1a.Objectives (from AD-416)
The objective of this cooperative research project is to operate a fall and winter rice nursery for the purpose of advancing plant generations and seed increase.
1b.Approach (from AD-416)
The Dale Bumpers National Rice Research Center (DBNRRC) of the USDA, ARS, SPA will provide rice seed stock for increase and harvest the plots. The Cooperator will plant and manage the research plots during the growing season.
The Puerto Rico winter nursery was successfully used to advance four rice mapping populations and other materials for seed increase, and to rejuvenate germplasm seed stocks. Two populations, including 438 recombinant inbred lines that are being used to identify chromosomal regions linked with resistance genes for blast disease, were advanced to the F8 generation. Two other populations, including 600 individuals of recombinant inbred lines, were advanced to the F6 generation for the objective of identifying genes that will improve the nutritional value of rice. Other materials included 114 accessions of the USDA rice core collection, 74 accessions of the USDA rice mini-core collection, and 10 accessions of aromatic germplasm. A number of core and mini-core accessions are too late to mature properly in the Arkansas environment, and thus the Puerto Rico location facilitates production of seed of these materials so that they can be deposited in the Genetic Stock Oryza (GSOR) and NSGC Collections. The aromatic accessions, including a wild type and nine derived mutants, and hundreds of other breeding lines were characterized and harvested for further genetic study. The cooperator accurately planted the materials, managed the field during the growing season, provided facilities and expertise for harvesting and processing the seed, and coordinated seed inspection with APHIS authorities prior to shipment of the seed to Arkansas.
This project was monitored through quarterly phone calls and email correspondence, as well as two on-site visits.