Location: Tropical Crops and Germplasm Research
2025 Annual Report
Objectives
1. Maintain the safety, genetic integrity, health, and viability of priority genetic resources through seed increases and release of quarantined NPGS accessions of grain genetic resources.
2. Generate phenotypic evaluation and morphological characterization data for genetic resources cultivated for regeneration and/or release from quarantine and incorporate those data into the GRIN-Global information management system.
Approach
Select and treat seed for freedom of signs and symptoms of pathogens; conduct annual disease surveys; inspect and verify status of plants (PPQ); grow quarantined and/or photoperiod-sensitive crops, report new diseases, maintain low pest levels, bag heads prior to anthesis; identify diseases and take regulatory action; record key descriptor information for entry into Germplasm Resources Information Network (GRIN), harvest seed and examine for disease symptoms; and return seed to National Plant Germplasm System (NPGS).
Progress Report
Progress was made on Objective 1. Maintain the safety, genetic integrity, health, and viability of priority genetic resources through seed increases and release of quarantined NPGS accessions of grain genetic resources. The preservation of germplasm collections is imperative for the success of plant breeding programs. A total of 420 non-quarantine sorghum accessions and 840 non-quarantined photoperiod sensitive pearl millet accessions with low seed viability or quantity were regenerated at the Germplasm Introduction and Research Unit (GIRU) in St. Croix, U.S. Virgin Islands. Likewise, 50 non-quarantined, photoperiod sensitive cowpea, 20 non-quarantined, photoperiod sensitive Ipomoea accessions, 20 non-quarantined photoperiod sensitive cucurbit accessions with low seed viability were regenerated at GIRU. Certainly, this regeneration process is an essential part of the success of the National Plant Germplasm System.
Partial progress was made on Objective 2. Generate phenotypic evaluation and morphological characterization data for genetic resources cultivated for regeneration and/or release from quarantine and incorporate those data into the GRIN-Global information management system. Due to the vacancy of the Agriculture Research Technician at GIRU was not possible to collect all phenotypic descriptor information for all accessions during the regeneration process. The technician hired this year accepted the Deferred Resignation Program 2.0 thus leaving the position vacant.
In addition to these objectives, the USDA frost-free winter nursery was provided to eight soybean breeders and geneticists on the mainland. This year, multiple F1, bulk and Single Seed Descent (SSD) plots were planted at the USDA-ARS Research farm at Isabela, Puerto Rico. A total of 29,940 square feet of soybean were planted, of which 20,280 square feet received artificial light supplementation to increase the yield and flowering of the plots. Phenotypic data such as a stand count, flower color, pubescence color and pod color were collected for some plots. The harvesting procedures ranged from pod picking, single plant, and bulk harvest, while some material had a delayed harvest time. Certainly, this winter nursery service is essentially for the quick release of new soybean varieties in the U.S. and to provide for continued improvement of soybean germplasm.
Accomplishments