Intraspecific cross-compatibility in ornamental pepper

Abstract

The production of Capsicum for ornamental purposes in Brazil has increased in recent years. To support the activities of this promising market, it is essential to develop new cultivars by hybridization. The knowledge of cross compatibility is also important in plant evolution research as it provides new genetic combinations and promotes speciation. There are few records of intraspecific compatibility studies in Capsicum. The objective of this work was to evaluate and describe cross compatibilities in accessions of Capsicum annuum. This experiment was carried out in a greenhouse at Universidade Federal da Paraiba (UFPB). Nine lines of Capsicum annuum (UFPB 45, UFV 46, UFPB 132, UFPB 134, UFPB 390, UFPB 392, UFV443, UFV 448, and UFV 449), belonging to the Horticultural Germplasm Bank of UFPB and Universidade Federal de Viçosa (UFV), were chosen for the study based on their broad genetic background and phenotypic diversity. They were crossed according to a full diallel schedule. The manual crosses were made at pre-anthesis stage in emasculated flowers. The percentage of fruit set was estimated as the number of fruits formed divided by the total crosses made and varied from 20 to 100%. The intraspecific compatibility varied both with the direction of the crossings and the parents used in the crossing, showing intraspecific incompatibility exists and depends on the genotypes. Parthenocarpic fruits and fruits with very few seeds were observed. Some fruits showed apocarpy. Some crosses showed anthocyanin in the placenta tissues. The knowledge of the intraspecific compatibility as well as of the direction of crossing is extremely important for success in hybrid breeding programs.