Selection strategies in a segregating passion fruit population aided by classic and molecular techniques

Abstract

Combining the use of agronomic, disease-resistance, and molecular information can greatly contribute to genetic progress in breeding programs. This study was developed to estimate the genetic distance between genotypes derived from backcrosses and their parents using morphoagronomic and molecular information and information pertaining to resistance to the Cowpea aphid-borne mosaic virus (CABMV), and indicate genotypes with potential for generation advancement. The studied population consisted of 91 genotypes from the first backcross, one interspecific hybrid, and the species Passiflora setacea and P. edulis. For morphoagronomic characterization, the traits number of fruits, total fruit weight, average fruit weight, and area under the disease progress curve (AUDPC, related to resistance to CABMV) were evaluated. Fourteen microsatellite primers were used to estimate genetic diversity among the genotypes, estimate diversity parameters and quantify the proportion of parental genome in the evaluated genotypes. The use of morphoagronomic and molecular information revealed the existence of genetic variability among the genotypes. The mean number of alleles is close to that expected for the population. Observed heterozygosity (0.42) was higher than the expected heterozygosity (0.30), indicating an elevated number of heterozygous individuals in the population. Due to their good agronomic performance, resistance to the virus, and genotypic and phenotypic distinction, genotypes 484 and 312 are recommended to compose the future stages of the passion fruit breeding program aimed at resistance to CABMV.

Research Article Evaluation of resistance to <i>Cowpea</i><i> aphid-borne</i> <i>mosaic</i> <i>virus</i> in passion fruit backcrosses for recurrent selection and development of resistant cultivars

“…The second generation of backcrossing (BC 2 ) was obtained by crossing between first generation of backcrossing (BC 1 ) selected by Preisigke et al (2020b) and Passiflora edulis UENF Rio Dourado (Viana et al, 2016). The crossings were made at the UENF experimental station located at Escola Agrícola Antônio Sarlo, in Campos dos Goytacazes, in the northern region of the state of Rio de Janeiro, between January and June 2017 (Table 1).…”

“…The crossings were made at the UENF experimental station located at Escola Agrícola Antônio Sarlo, in Campos dos Goytacazes, in the northern region of the state of Rio de Janeiro, between January and June 2017 (Table 1). Santos et al (2015); BC1 = First generation of backcrossing selected in the study of Preisigke et al (2020b); BC2 -Full-sib families the second backcrossing generation; Cultivar UENF Rio Dourado -passion fruit genetic breeding program by recurrent selection in the study of Viana et al (2016).…”

“…Where: Yi = proportion of the disease in the i-th observation; Ti = time in days of the i-th observation; n = number of observations (Campbell and Madden, 1990). After estimating the AUDPC's for young leaves and the percentage of symptoms in the plant, a simple arithmetic mean was performed between them to obtain the average area under the disease progress curve (AAUDPC) according to Preisigke et al (2020b). About fruit production (FP), all the fruits produced by each genotype from June 2018 to July 2019 (harvest 2018/2019) were weighed on a precision scale.…”

Identification, Selection, and Response of Radiation Induced Towuti Mutant Rice (Oryza Sativa L.) in Drought Stress Conditions

“…Changes in the genetic structure of individuals and populations of plants can be done by genetic mutations [20][21][22]. Plant genetic mutations can be induced by using mutagens such as gamma-ray irradiation [23,24]. Mutation breeding using gammaray irradiation is efficacious to improve plant varieties [25].…”

Cowpea aphid-borne mosaic virus (CABMV) in Passiflora by qPCR analysis reveals asymptomatic plants with viruses and new species with immunity

“…Despite being the largest worldwide producer, the average productivity of 14.1 t ha -1 is low [3]. This low yield, in part, is associated with high severity of the passion fruit woodiness disease, attributed to Cowpea aphid-borne mosaic virus -CABMV [4][5][6][7].…”