Behavior of F1 hybrids of Coffea arabica for vigor, production and fertility in Central America

The varieties of C. arabica cultivated in Central America resulted from a very small genetic base. Since 1992, PROMECAFE, CATIE and the French Cooperation have started on an original program of genetic improvement, based on crosses between traditional varieties (Caturra, Catuai) or some Timer Hybrid derivatives (Catimor, Sarchimor), and spontaneous coffee trees (Ethiopia, Sudan). The objectives of this program are to increase the adaptability and productivity of varieties, and to improve the resistance ro the main pests and diseases of the region (leaf rust and nematodes), without lowering the quality of produced coffee. Selected Fl hybrids will be multiplied in vitro by somatic embryogenesis. The use of this technique permits to shorten the selection cycle from 30 to 10 years and to propose many lens of Fl hybrids for the highly varied conditions of Central America. Observations concerning growth, production and fertility were initiated in two field experiments. The first results showed that Fl hybrids are more vigorous and more productive that the best varieties. The hybrid vigor. calculated on the best parent, frequently reached 30% for the yield. The gains realized for the seed weight were poor. However, the Fl families generally presented a lower fertility than the varieties.