Academic literature on the topic 'Passiflora – Phylogeny'

A striking example of plant/pollinator trait matching is found between Andean species of Passiflora with 6–14-cm-long nectar tubes and the sword-billed hummingbird, Ensifera ensifera , with up to 11-cm-long bills. Because of the position of their anthers and stigmas, and self-incompatibility, these passionflower species depend on E. ensifera for pollination. Field observations show that the bird and plant distribution match completely and that scarcity of Ensifera results in reduced passionflower seed set. We here use nuclear and plastid DNA sequences to investigate how often and when these mutualisms evolved and under which conditions, if ever, they were lost. The phylogeny includes 26 (70%) of the 37 extremely long-tubed species, 13 (68%) of the 19 species with tubes too short for Ensifera and four of the seven bat-pollinated species for a total of 43 (69%) of all species in Passiflora supersection Tacsonia (plus 11 outgroups). We time-calibrated the phylogeny to infer the speed of any pollinator switching. Results show that Tacsonia is monophyletic and that its stem group dates to 10.7 Ma, matching the divergence at 11.6 Ma of E. ensifera from its short-billed sister species. Whether pollination by short-billed hummingbirds or by Ensifera is the ancestral condition cannot be securely inferred, but extremely long-tubed flowers exclusively pollinated by Ensifera evolved early during the radiation of the Tacsonia clade. There is also evidence of several losses of Ensifera dependence, involving shifts to bat pollination and shorter billed birds. Besides being extremely asymmetric—a single bird species coevolving with a speciose plant clade—the Ensifera / Passiflora system is a prime example of a specialized pollinator not driving plant speciation, but instead being the precondition for the maintenance of isolated populations (through reliable seed set) that then underwent allopatric speciation.

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.

Camellia sinensis is one of the major crops grown in Taiwan and has been widely cultivated around the island. Tea leaves are prone to various fungal infections, and leaf spot is considered one of the major diseases in Taiwan tea fields. As part of a survey on fungal species causing leaf spots on tea leaves in Taiwan, 19 fungal strains morphologically similar to the genus Diaporthe were collected. ITS (internal transcribed spacer), tef1-α (translation elongation factor 1-α), tub2 (beta-tubulin), and cal (calmodulin) gene regions were used to construct phylogenetic trees and determine the evolutionary relationships among the collected strains. In total, six Diaporthe species, including one new species, Diaporthe hsinchuensis, were identified as linked with leaf spot of C. sinensis in Taiwan based on both phenotypic characters and phylogeny. These species were further characterized in terms of their pathogenicity, temperature, and pH requirements under laboratory conditions. Diaporthe tulliensis, D. passiflorae, and D. perseae were isolated from C. sinensis for the first time. Furthermore, pathogenicity tests revealed that, with wound inoculation, only D. hongkongensis was pathogenic on tea leaves. This investigation delivers the first assessment of Diaporthe taxa related to leaf spots on tea in Taiwan.

Passionfruit plantation in Vietnam increased to 10,000 ha in 2019. However, the outbreaks of passionfruit woodiness disease (PWD) have become a serious threat for the production. In this study, five virus isolates DN1, DN4, NA1, GL1 and GL2 were collected from different areas of Vietnam. Their causal roles for PWD were verified by back inoculation to passionfruit. Analyses of coat protein (CP) and genomic sequences revealed that GL1 isolate is closely related to East Asia Passiflora virus (EAPV) AO strain of Japan (polyprotein nt/aa identities of 98.1% / 98.2%), while GL2 isolate is related to Telosma mosaic virus (TelMV) isolate PasFru, China (polyprotein nt/aa identities of 87.1% / 90.9%). CP comparison, host range and cytological characterization indicated that DN1, DN4 and NA1 are potyviruses, but different from EAPV and TelMV. Phylogenic analyses of their CP and genome sequences indicated that these three isolates and passionfruit severe mottle-associated virus Fujian isolate of China belong to a distinct clade, which does not satisfy the threshold (76% nt identity of polyprotein) to be regarded as any of potyviral species. Thus, a new species name of “Passiflora mottle virus” has been proposed by ICTV. A rabbit antiserum was produced against the CP of DN1 and it can discriminate Passiflora mottle virus (PaMoV) from TelMV and EAPV in western blotting and ELISA without cross reactions. Field surveys of 240 samples by ELISA and RT-PCR disclosed that PWD in Vietnam is mainly caused by PaMoV; followed by EAPV, mixed-infection of PaMoV/EAPV, and rare cases of TelMV.