Crossability and evaluation of incompatibility barriers in crosses between capsicum species

Abstract

The objectives of this study were to estimate the crossability rate in combinations of and assess the occurrence of incompatibility barriers between Capsicum species. The species C. annuum, C. chinense, C. frutescens, C. baccatum var. pendulum, and C. baccatum var. baccatum were crossed and the number of hand-pollinations and of resulting fruits and plants was registered. The resulting hybrids were evaluated for their pollen viability and in the crosses that produced no hybrids, the in vivo germination of pollen grains was assessed. Some crosses generated hybrids, while others produced no fruit or, despite generating fruits, no plants grew from them. The crossability rate between species of the complex C. annuum and C. baccatum ranged from 2.2% to 3.7%, and was 14.6% between species of the complex C. annuum. A pre-fertilization barrier was observed in the non-germination of pollen grains, as well as post-fertilization barriers consisting of embryo death, lack of vigor and hybrid sterility