Identification of pepper (Capsicum annuum L.) accessions with large or small fruit that have a high degree of parthenocarpy

Abstract In pepper ( Capsicum annuum L.), parthenocarpic accessions have not been available for use in practical breeding. To obtain accessions with a high degree of parthenocarpy, we compared the relative rates of fruit set between unpollinated and pollinated conditions (a criterion for a pepper's parthenocarpic ability). After surveying 173 accessions collected from around the world, we selected some promising candidates for closer examination. The fruit set rate of ‘CNPH2622’ did not change with or without pollination, indicating high parthenocarpic fruit set ability. ‘Shishitoh’, an accession that produces small fruit, was a highly parthenocarpic variety, as was previously reported. Parthenocarpic fruit of ‘CNPH2622’ and ‘Shishitoh’ grew well, but were smaller than those produced by pollination, indicating that these cultivars had high fruit set abilities, but inadequate fruit enlargement. We also found two unique accessions, ‘INT/RUSSIA/2001/1579’, which produced many unpollinated fruit that never enlarged, and ‘INT/RUSSIA/2001/280’, which never set fruit without pollination. These accessions will be good tools for studying fruit enlargement in pepper. Fruiting properties of ‘CNPH2622’, ‘Shishitoh’, and ‘INT/RUSSIA/2001/1579’ did not differ after removal of either their anthers or their style.