The objective of this study was to use a severity scale for some passion fruit diseases, in order to identify sources of resistance. Seventy-five accessions of Passiflora spp. were evaluated under field conditions and high natural infection of pathogens. Symptoms of virus severity in the leaves (VILE), fruits (VIFR) and distribution in the plant (VIPL), as well as scab on fruit and branches (SCFR and SCBR, respectively) and anthracnose in fruits (ANFR), were analyzed. High variability for disease resistance was observed, although few accessions were classified as resistant to VILE, VIFR and VIPL. Only BGM237 (P. setacea) was considered resistant of these three types of virus evaluation. The most of yellow and purple passion fruit accessions showed some degree of susceptibility to one or another virus symptom. P. alata and P. cincinnata were more resistant to SCBR, although P. alata showed more resistance to SCFR. Some accessions of P. edulis were moderately resistant to SCFR and SCBR. The majority of P. alata, P. cincinnata and P. setacea accessions do not showed symptoms of anthracnose in the fruits. The severity scale proposed was useful to separate the accessions of passion fruit in different classes of disease resistance.
Passiflora; breeding; genetic resistance; genetic variability
