Reação de germoplasma e híbridos de mamoeiro à mancha-de-phoma (Phoma caricae-papayae) em condições de campo

Abstract

With the objective of evaluating germplasm and hybrids of papaya for their reaction to phoma-spot in leaves, three experiments were performed in a completely randomized block design with two replications at Agricultural Caliman S/A, in Linhares, Espírito Santo, Brazil. The incidence and severity of phoma-spot were evaluated in leaves of 50 genotypes and 68 hybrids. The lowest levels of disease severity were observed in 'Maradol', 'Maradol GL', 'Papaya 46', 'Tailândia', and 'SH 15-04' whereas the lowest incidences were detected in 'Maradol', 'Maradol GL', 'Americano', 'Tailândia' and 'Baixinho de Santa Amália'. The hybrids 'Calimosa x Tailândia', 'Calimosa x Maradol', 'Sekati x Caliman AM' and 'Sekati x JS 12' presented the lowest levels of severity, whereas 'Americano x Waimanalo', 'Sekati x JS 12', 'Maradol x Taiwan et' and 'Maradol x Caliman G' had the lowest incidence of disease. These results should be useful as a guide in breeding for resistance to phoma-spot of the papaya crop through hybridization, as well as in the recommendation of cultivars, seeking to reduce the necessity of chemical control in papaya crops.