Bioprospection and molecular phylogeny of culturable endophytic fungi associated with yellow passion fruit

Endophytic microorganisms live inside the plants without causing any damage to their hosts. In the agricultural field, these endophytes might be a strategy of biological control for phytopathogens. We aimed to isolate endophytic fungi from yellow passion fruit (Passiflora edulis) leaves, evaluating its biocontrol capacity by in vitro antagonism against phytopathogen Colletotrichum sp. CNPU378. We also carried out greenhouse experiments in bean seedlings. A high colonization frequency was obtained (89%), and the molecular identification based on DNA sequencing attested Colletotrichum as the most frequent genus and minor occurrence of Curvularia endophytes. The endophytes tested showed different types of competitive interactions in in vitro antagonism inhibition rate ranging from 28.8 to 48.8%. There were 10 promising antagonists tested for their antagonist activity of crude extracts of secondary metabolites, in which strain PE-36 (20.8%) stood out among the other strains evaluated. In the greenhouse assay, plants inoculated only with endophyte Colletotrichum sp. PE-36 was symptomless and suggest that the endophyte strengthened the growth promotion in common bean plants, especially in the root length and number of leaves when compared to control plants and other treatments. Despite many fungi of Colletotrichum genus being described as causative agents of anthracnose, in this study, the plant sampled was colonized predominantly by Colletotrichum endophytes living in asymptomatic relationship. By the way, we come across a Colletotrichum sp. endophyte able to antagonize a Colletotrichum sp. pathogen.

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Evaluation of different methods to overcome in vitro seed dormancy from yellow passion fruit

AFRICAN JOURNAL OF BIOTECHNOLOGY ◽

10.5897/ajb11.1743 ◽

2014 ◽

Vol 13 (36) ◽

pp. 3657-3665 ◽

Cited By ~ 2

Author(s):

M. M. Rego, ◽

E. R. Rego, ◽

L. P. U. Nattrodt, ◽

P. A. Barroso, ◽

F. L. Finger, ◽

...

Keyword(s):

Seed Dormancy ◽

Passion Fruit ◽

Yellow Passion Fruit

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Modelling the in vitro pre-infection dynamics of Colletotrichum spp. isolated from yellow passion fruit in function of environmental variables

10.1101/781963 ◽

2019 ◽

Author(s):

Karinna Vieira Chiacchio Velame ◽

Hermes Peixoto Santos Filho ◽

Adelise de Almeida Lima ◽

Carlos Augusto Dórea Bragança ◽

Francisco Ferraz Laranjeira

Keyword(s):

Environmental Variables ◽

Climatic Conditions ◽

Passion Fruit ◽

Yield Reduction ◽

Post Harvest ◽

Infection Dynamics ◽

Mycelia Growth ◽

Wetness Period ◽

Yellow Passion Fruit

AbstractBrazil is the largest world producer of yellow passion fruit, but the mean yield (14.3t.ha-1) is less than half the potential of the crop. Part of this difference can be explained by plant health problems, including anthracnose caused by Colletotrichum spp. In regions with favorable climatic conditions, anthracnose can be a factor of significant yield reduction, but these regions have not yet been zoned. The objective of this study was to model the pre-infection dynamics of the fungus. The influence of temperature and photoperiod was studied on mycelia growth, sporulation and conidia germination. Mathematical models were fitted to the results and the optima for the environmental variables were estimated. The maximum mycelia growth was estimated to occur at 26.5°C. Between 24.5°C and 28.5°C the fungus grew from 95% to 100% of the estimated maximum. Temperatures below 13°C or above 34°C were harmful to mycelia growth. Temperatures over 26°C were the most favorable to sporulation while below 13°C sporulation was only 5% of the maximum. Optimum germination occurred between 25°C and 29°C with the ideal wetness period between 11h and 13h. These results can be used as a basis for zoning the risk of anthracnose occurrence in passion fruit producing regions.Significance and Impact of the StudyMany diseases affect the yellow passion fruit crop, limiting its yield; among them anthracnose, caused by Colletotrichum spp. The disease occurs in both field (leaf and stem symptoms) and post-harvest (fruits) conditions. Understanding the role environmental conditions play in the biological cycle of such diseases is essential for developing management strategies. By modelling mycelial growth, spore production and spore germination of Colletotrichum spp. as affected by temperature, photoperiod and wetness period, it was possible to characterize the pathogen’s pre-infectional dynamics. The results should be used as a first approximation to estimate the risk of anthracnose occurrence in pre- or post-harvest.

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Resistance to Passion fruit woodiness virus in Transgenic Passionflower Expressing the Virus Coat Protein Gene

Plant Disease ◽

10.1094/pd-90-1026 ◽

2006 ◽

Vol 90 (8) ◽

pp. 1026-1030 ◽

Cited By ~ 33

Author(s):

F. Trevisan ◽

B. M. J. Mendes ◽

S. C. Maciel ◽

M. L. C. Vieira ◽

L. M. M. Meletti ◽

...

Keyword(s):

Coat Protein ◽

Transgenic Plants ◽

In Vitro Selection ◽

Passion Fruit ◽

Cp Gene ◽

Virus Coat ◽

Passion Fruit Woodiness Virus ◽

Leaf Disks ◽

Yellow Passion Fruit

We report the use of the coat protein (CP) gene from Passion fruit woodiness virus (PWV) to produce resistant transgenic plants of yellow passion fruit. A full-length CP gene from a severe PWV isolate from the state of São Paulo, Brazil (PWV-SP) was cloned into pCAMBIA 2300 binary vector, which was further introduced into Agrobacterium tumefaciens strain EHA 105. Leaf disks were used as explants for transformation assays, e.g., 2,700 and 2,730 disks excised from plants from the Brazilian cultivars IAC-275 and IAC-277, respectively. In vitro selection was performed in kanamycin. After transferring to the elongation medium, 119 and 109 plantlets of IAC-275 and IAC-277, respectively, were recovered. Integration of the PWV CP gene was confirmed in seven of eight plants evaluated by Southern blot analysis, showing different numbers of insertional events for the CP gene. Three transgenic plants (T3, T4, and T7) expressed the expected transcript, but the 32 kDa PWV CP was detected by Western blot in only two plants (T3 and T4). The results of three successive mechanical inoculations against the transgenic plants using three PWV isolates showed that the primary transformant T2 of IAC-277 was immune to all isolates.

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In vitro induction of autotetraploids from diploid yellow passion fruit mediated by colchicine and oryzalin

Plant Cell Tissue and Organ Culture (PCTOC) ◽

10.1007/s11240-011-9995-6 ◽

2011 ◽

Vol 107 (3) ◽

pp. 451-459 ◽

Cited By ~ 20

Author(s):

M. M. Rêgo ◽

E. R. Rêgo ◽

C. H. Bruckner ◽

F. L. Finger ◽

W. C. Otoni

Keyword(s):

Passion Fruit ◽

In Vitro Induction ◽

Yellow Passion Fruit

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Characterization of cellular, biochemical and genomic features of the diazotrophic plant growth-promoting bacterium Azospirillum sp. UENF-412522, a novel member of the Azospirillum genus

10.1101/2021.05.06.442973 ◽

2021 ◽

Author(s):

Gustavo L. Rodrigues ◽

Filipe P. Matteoli ◽

Rajesh K. Gazara ◽

Pollyanna S. L. Rodrigues ◽

Samuel T. dos Santos ◽

...

Keyword(s):

Plant Growth ◽

Plant Growth Promotion ◽

Growth Promotion ◽

Carbon Sources ◽

Phylogenetic Reconstruction ◽

Passion Fruit ◽

In Vitro Assays ◽

Fresh Matter ◽

Beneficial Effects

Given their remarkable beneficial effects on plant growth, several Azospirillum isolates currently integrate the formulations of various commercial inoculants. Our research group isolated a new strain, Azospirillum sp. UENF-412522, from passion fruit rhizoplane. This isolate uses carbon sources that are partially distinct from closely-related Azospirillum isolates. Scanning electron microscopy analysis and population counts demonstrate the ability of Azospirillum sp. UENF-412522 to colonize the surface of passion fruit roots. In vitro assays demonstrate the ability of Azospirillum sp. UENF-412522 to fix atmospheric nitrogen, to solubilize phosphate and to produce indole-acetic acid. Passion fruit plantlets inoculated with Azospirillum sp. UENF-41255 showed increased shoot and root fresh matter, as well as root dry matter, further highlighting its biotechnological potential for agriculture. We sequenced the genome of Azospirillum sp. UENF-412522 to investigate the genetic basis of its plant-growth promotion properties. We identified the key nif genes for nitrogen fixation, the complete PQQ operon for phosphate solubilization, the acdS gene that alleviates ethylene effects on plant growth, and the napCAB operon, which produces nitrite under anoxic conditions. We also found several genes conferring resistance to common soil antibiotics, which are critical for Azospirillum sp. UENF-412522 survival in the rhizosphere. Finally, we also assessed the Azospirillum pangenome and highlighted key genes involved in plant growth promotion. A phylogenetic reconstruction of the genus was also conducted. Our results support Azospirillum sp. UENF-412522 as a good candidate for bioinoculant formulations focused on plant growth promotion in sustainable systems.

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