Germoplasma de Coffea racemosa e seu potencial no melhoramento do cafeeiro

Abstract

Plants from artificial and natural crosses between C. arábica x C. racemosa, as well as two coffee trees resulting from the backcross (C. racemosa x C. arábica) x C. arábica, were evaluated for resistance to the leaf miner (Perileucoptera coffeella) and drought resistance, under field conditions. All examined plants showed resistance to Perileucoptera coffeella attack and were also resistant to long drought periods. These characteristics were inherited from C. racemosa parent. The coffee plants 1195-5-6-1 and 1195-5-6-2, from the backcross (C. racemosa x C. arábica) x C. arábica, have 45 and 44 somatic chromosomes, respectively. Six out of 10 examined seedlings from a selfed progeny of the 1195-5-6-2 tree revealed to be tetraploid. Besides presenting C. arábica characteristics such as branching type, fruit color and medium fruit ripening period, it displayed also partial self-fertility. Due to its favourable genetic constitution it is being used as a source of genes for drought and leaf-miner resistance in C. arábica breeding program aiming both these characteristics.