Essential oil phytocomplex activity, a review with a focus on multivariate analysis for a network pharmacology-informed phytogenomic approach

Thanks to omic disciplines and a systems biology approach, the study of essential oils and phytocomplexes has been lately rolling on a faster track. While metabolomic fingerprinting can provide an effective strategy to characterize essential oil contents, network pharmacology is revealing itself as an adequate, holistic platform to study the collective effects of herbal products and their multi-component and multi-target mediated mechanisms. Multivariate analysis can be applied to analyze the effects of essential oils, possibly overcoming the reductionist limits of bioactivity-guided fractionation and purification of single components. Thanks to the fast evolution of bioinformatics and database availability, disease-target networks relevant to a growing number of phytocomplexes are being developed. With the same potential actionability of pharmacogenomic data, phytogenomics could be performed based on relevant disease-target networks to inform and personalize phytocomplex therapeutic application

Neuromuscular Taping Application in Counter Movement Jump: Biomechanical Insight in a Group of Healthy Basketball Players.

Kinesiologic elastic tape is widely used for both clinical and sport applications although its efficacy in enhancing agonistic performance is still controversial. Aim of the study was to verify in a group of healthy basketball players whether a neuromuscular taping application (NMT) on ankle and knee joints could affect the kinematic and the kinetic parameters of the jump, either by enhancing or inhibiting the functional performance. Fourteen healthy male basketball players without any ongoing pathologies at upper limbs, lower limbs and trunk volunteered in the study. They randomly performed 2 sets of 5 counter movement jumps (CMJ) with and without application of Kinesiologic tape. The best 3 jumps of each set were considered for the analysis. The Kinematics parameters analyzed were: knees maximal flexion and ankles maximal dorsiflexion during the push off phase, jump height and take off velocity. Vertical ground reaction force and maximal power expressed in the push off phase of the jump were also investigated. The NMT application in both knees and ankles showed no statistically significant differences in the kinematic and kinetic parameters and did not interfere with the CMJ performance. Bilateral NMT application in the group of healthy male basketball players did not change kinematics and kinetics jump parameters, thus suggesting that its routine use should have no negative effect on functional performance. Similarly, the combined application of the tape on both knees and ankles did not affect in either way jump performance

A breach in plant defences: Pseudomonas syringae pv. actinidiae targets ethylene signalling to overcome Actinidia chinensis pathogen responses

Ethylene interacts with other plant hormones to modulate many aspects of plant metabolism, including defence and stomata regulation. Therefore, its manipulation may allow plant pathogens to overcome the host’s immune responses. This work investigates the role of ethylene as a virulence factor for Pseudomonas syringae pv. actinidiae (Psa), the aetiological agent of the bacterial canker of kiwifruit. The pandemic, highly virulent biovar of this pathogen produces ethylene, whereas the biovars isolated in Japan and Korea do not. Ethylene production is modulated in planta by light/dark cycle. Exogenous ethylene application stimulates bacterial virulence, and restricts or increases host colonisation if performed before or after inoculation, respectively. The deletion of a gene, unrelated to known bacterial biosynthetic pathways and putatively encoding for an oxidoreductase, abolishes ethylene production and reduces the pathogen growth rate in planta. Ethylene production by Psa may be a recently and independently evolved virulence trait in the arms race against the host. Plantand pathogen-derived ethylene may concur in the activation/suppression of immune responses, in the chemotaxis toward a suitable entry point, or in the endophytic colonisation

First Report of Pseudomonas syringae pv. actinidiae on Kiwifruit Pollen from Argentina

none6noPublished online: 6 Nov 2017In recent years, in the Mar del Plata area of Argentina, many kiwifruit orchards composed of only male plants (Actinidia deliciosa ‘Chieftain’) have been established for pollen production and commercialization, since the country was considered unaffected by Pseudomonas syringae pv. actinidiae (Psa). When mature, the anthers are detached and dried, and grains of pollen are collected with a portable cyclonic pollen collector. Then, routine controls aimed to assess the risk of infection by Psa, the causal agent of kiwifruit bacterial canker (Takikawa et al. 1989), are carried out by plating 1-g aliquots of pollen on semiselective medium (modified KB) and incubating plates for 48 to 72 h at 27°C. In February 2015, during one of these controls, some bacterial colonies with morphological features similar to Psa were detected. After purification, four of them (labeled as Arg1.1 to Arg2.3) were found to be gram-negative, nonfluorescent, positive for levan production, and caused hypersensitive response on tobacco. The isolates were further characterized and tested negative for cytochrome C oxidase, oxidative in glucose metabolism, negative for aesculine hydrolysis, and negative for nitrate reduction. Genomic DNA was purified from each isolate, quantified, and diluted to a final concentration of 20 ng μl−1. Pathovar specific PCR assays (Gallelli et al. 2011; Rees-George et al. 2010) generated amplicons of the expected sizes, confirming the identity of all the isolates as Psa. Moreover, the sequences of housekeeping genes gapA, gltA, gyrB, and rpoD were obtained and found identical between the isolates. When BLASTed in GenBank, they showed 100% identity to analog sequences of Psa biovar 3 (Chapman et al. 2012). The housekeeping gene sequences of the isolate Arg2.1 were deposited (accessions KY327791–94). Pathogenicity was confirmed by artificial inoculation of A. deliciosa ‘Hayward’ and A. chinensis plantlets. Ten 3-month-old plantlets, each 30 cm high, were singularly dipped for 1 min in a bacterial cell suspension (8 × 106 CFU/ml in 0.01 M MgSO4) of Arg2.1 isolate and then incubated at high RH (80%), with 14 h daylight and 24/21°C day/night temperature cycle. Positive and negative controls were likewise inoculated with Psa virulent strain CFBP 7286 and 0.01 M MgSO4, respectively. After 7 days, brown spots with pale green halos were observed on inoculated plants. According to Koch’s postulates, bacteria were reisolated from diseased tissues and have been found identical to the original strains in morphology, biochemical tests, and pathovar-specific PCR products. Negative control plants did not develop any symptoms. To our knowledge, this is the first scientific proof of the presence of Psa in Argentina, and specifically on kiwifruit pollen but not on plants, at the pollen harvest time. This result requires great attention to the potential risk of pathogen spread in the future. Extensive monitoring and laboratory analyses are in progress.openBalestra, G. M.; Buriani, Giampaolo; Cellini, Antonio; Donati, Irene; Mazzaglia, A.; Spinelli, FrancescoBalestra, G. M.; Buriani, Giampaolo; Cellini, Antonio; Donati, Irene; Mazzaglia, A.; Spinelli, Francesc

Use of loop-mediated isothermal amplification (LAMP) as diagnosis tool to identify Psa in open field

Pseudomonas syringae pv. actinidiae (Psa) is the causal agent of bacterial canker kiwifruit. This disease spread very rapidly, also due to the circulation of infected plant material, till becoming pandemic. In order to prevent local spread and future introduction into Psa-free area, the early diagnosis of asymptomatic material is essential. Moreover, Psa symptoms in open filed are represented, from spring to autumns, mainly by leaf spots which may be caused also by other pathogens (i.e. P. syringae pv. syrinagae). Thus a fast, reliable, easy to use an inexpensive diagnostic method may represent a key tool screen nursery material or to tailor control treatments, orchard management inputs. Due to its plasticity, cost effective, rapidity and sensitivity, loop-mediated isothermal amplification (LAMP) assay is an ideal approach to develop such diagnostic tool. LAMP primers were designed on the AvrPT01 protein, a virulence factor specific of Psa and tested for specificity with genomic DNA from different Pseudomonas syringae pathovars (tomato, tobacco, glycinea, syringae and theae), other bacteria commonly found on Actinidia species (Pseudomonas viridflava, Pantoea agglomerans, Pantoea vagans, Paenibacillus spp, Pseudomonas fluorescens) and other bacteria not related to kiwifruit (Erwinia amylovora, Escherichia coli). Positive diagnosis, which is indicated in a clear color change or the reaction medium, was found only on Psa pathovars 1, 2 and 3. The method was also tested using crude extracts from infected Actinidia deliciosa and Actinidia chinensis plants. The sensibility of Lamp-based methodology here described was 1000 CFU/ml, comparable to other molecular tools commonly used for Psa identification such as end-point PCR and QPC

Screening of microbial biocoenosis of Actinidia chinensis for the isolation of candidate biological control agents against Pseudomonas syringae pv. actinidiae

The present study aimed to isolate and characterize candidate biological control agents against Pseudomonas syringae pv. actinidiae (Psa), the causal agent of kiwifruit bacterial canker. Biological control represents a promising strategy to reduce or complement the use of chemical pesticides. In the case of Psa, the common preventive strategies rely on the use of copper formulations. However, the use of copper has some severe limitations because of environmental concerns, phytotoxicity and the possible development of bacterial resistance. The use of copper is particularly hazardous during blooming, which is a phenological phase with a high risk of Psa infection. Therefore, the use of a biological control agent, especially selected to be active in this phenological phase, is an interesting control alternative. Bacterial biocoenosis, naturally present on flowers, was screened to identify species able to effectively reduce infection at blooming. Flowers from both Actinidia deliciosa and Actinidia chinensis were sampled in healthy and infected orchards, and culturable microorganisms were isolated and tested against Psa both in vitro and in planta. Among the 78 isolates, only two, belonging to Pseudomonas fluorescens, were able to inhibit Psa growth in vitro and to reduce disease incidence in planta. Further experiments will be performed in order to confirm these preliminary results and to optimize the use of candidate biocontrol agents under real conditions

Insect-mediated vectoring of Pseudomonas syringae pv. actinidiae

From 2008, kiwifruit production and the total cultivated area decreased considerably, due to the pandemic spread of the bacterial canker caused by Pseudomonas syringae pv. actinidiae (Psa). This bacterium is able to infect host plants via natural openings or wounds, such as those caused by sucking insects. These insects are also known to be able to transmit other bacterial pathogens in different species. The present work aimed to investigate the role of Metcalfa pruinosa Say, 1830, one of the most common sucking insects to affect kiwifruit vines, in plant-to-plant transmission of Psa. The percentage of contaminated insects collected from infected orchards was evaluated to confirm the ecological relevance of M. pruinosa in the spread of bacterial canker of kiwifruit. This study demonstrated the survival of Psa in the M. pruinosa digestive trait, and the insect’s ability to vector the pathogen to healthy plants

New insights on the bacterial canker of kiwifruit (Pseudomonas syringae pv. actinidiae)

Since 2008, Pseudomonas syringae pv. actinidiae, the causal agent of bacterial canker of kiwifruit has become the main pathogen of yellow and green fleshed kiwifruit. All major kiwifruit producing countries in the world have been affected by this bacterial pathogen, leading to substantial economic losses. This review presents the current knowledge on various aspects about the origin, epidemiology, detection and control strategies of Pseudomonas syringae pv. actinidia