Molecular and Aggressiveness Characterization of Isolates of Fusarium solani and Fusarium oxysporum f.sp. passiflorae Associated to Passion Fruit Wilting

Abstract

This work was carried out with the objective of performing a molecular and aggressiveness characterization of F. solani and F. oxysporum f.sp. passiflorae collected in the Pantanal, Cerrado and Amazon biomes. We selected the most aggressive isolates for use in breeding programs aiming resistance to Collar Rot and Fusariosis. For inoculation of the isolates of F. oxysporum f.sp. passiflorae the washed root method was used. The molecular characterization of the isolates was carried out by partial sequencing of the Transcribed Internal Spacer of the rDNA region. The isolates of F. solani formed two distinct groups in relation to aggressiveness. Among all isolates, FSUNEMAT 40 and FSUNEMAT 46 were the most aggressive. The model with K=2 was taken as the best model to explain the genetic structure of the F. solani populations, with clear combinations of genes from both gene pools. There were three groups with respect to the aggressiveness of the isolates of F. oxysporum f.sp. passiflorae, with the isolated FOUNEMAT 22 being the most aggressive. In view of these results, the isolates of F. solani collected in P. edulis in the state of Mato Grosso presented a high molecular variability independent from the biome of origin, and this was also observed in the tests of aggressiveness. The results indicate the need to consider the molecular variability and the aggressiveness of the pathogens in the evaluation of genotypes of sour passion fruit in programs of selection of resistant cultivars.

Different strategies for estimating genetic parameters for collar rot resistance characteristics in Passiflora spp.

“…The isolate used for the test belongs to the Universidade do Estado de Mato Grosso (UNEMAT, Cáceres) fungi collection. Fusarium solani FSUNEMAT40 was considered the most aggressive according to the reports of Marostega et al (2019).…”

“…The damage caused by F. solani to the passion fruit culture is serious, resulting in reduced production, cultivated area and orchard longevity. In addition to Brazil (Preisigke et al, 2015;Marostega et al, 2019), other producing countries recorded economic damage caused by this fungus, as in Colombia, where they reported losses between 90% and 100% in commercial crops (Ángel-García et al, 2018) and China (Wang et al, 2021).…”

“…There is no record of a sour passion fruit cultivar with this trait. However, there are reports of resistance in the species P. quadrangularis, P. nitida and P. cincinnata (Freitas et al, 2015a;Preisigke et al, 2015;Marostega et al, 2019). In this case, the breeder's challenge is to bring together pathogen resistance, high productivity, and fruit quality in one genotype.…”

Backcross Aiming at the Resistance of Passion Fruit to Soil Pathogen

“…The inoculation of F. solani was performed with the FSUNEMAT 40 inoculum, the most aggressive (Marostega et al, 2019). First, the preserved segments were transferred to Petri dishes containing PDA culture medium (potato-dextrose-agar) and maintained at 25 o C with a 12 h photoperiod for seven days in the BOD.…”

Genetic resistance to fusariosis and base rot in interspecific F1 progenies of passion fruit (Passiflora spp.)

“…For the tests of resistance to fusariosis and base rot, the most aggressive isolates from the UNEMAT library were used according to the results obtained by Marostega et al (2019). Research, Society and Development, v. 9, n. 11, e96091110519, 2020 (CC BY 4.0) | ISSN 2525-3409 | DOI: http://dx.doi.org/10.33448/rsd-v9i11.10519…”