Beauveria bassiana and Metarhizium anisopliae endophytically colonize cassava roots following soil drench inoculation

AbstractWe investigated the fungal entomopathogens Beauveria bassiana and Metarhizium anisopliae to determine if endophytic colonization could be achieved in cassava. An inoculation method based on drenching the soil around cassava stem cuttings using conidial suspensions resulted in endophytic colonization of cassava roots by both entomopathogens, though neither was found in the leaves or stems of the treated cassava plants. Both fungal entomopathogens were detected more often in the proximal end of the root than in the distal end. Colonization levels of B. bassiana were higher when plants were sampled at 7–9days post-inoculation (84%) compared to 47–49days post-inoculation (40%). In contrast, the colonization levels of M. anisopliae remained constant from 7–9days post-inoculation (80%) to 47–49days post-inoculation (80%), which suggests M. anisopliae is better able to persist in the soil, or as an endophyte in cassava roots over time. Differences in colonization success and plant growth were found among the fungal entomopathogen treatments

Fungal diversity associated to the olive moth, prays oleae Bernard : a survey for potential entomopathogenic fungi

Olive production is one of the main agricultural activities in Portugal. In the region of Trás-os-Montes this crop has been considerably affected by Prays oleae. In order to evaluate the diversity of fungi on P. oleae population of Trás-os-Montes olive orchards, larvae and pupae of the three annual generations (phyllophagous, antophagous and carpophagous) were collected and evaluated for fungal growth on their surface. From the 3828 larvae and pupae, a high percentage of individuals exhibited growth of a fungal agent (40.6%), particularly those from the phyllophagous generation. From all the moth generations, a total of 43 species from 24 genera were identified, but the diversity and abundance of fungal species differed between the three generations. Higher diversity was found in the carpophagous generation, followed by the antophagous and phyllophagous generations. The presence of fungi displaying entomopathogenic features was highest in the phyllophagous larvae and pupae, being B. bassiana the most abundant taxa. The first report of B. bassiana presence on P. oleae could open new strategies for the biocontrol of this major pest in olive groves, since the use of an already adapted species increases the guarantee of success of a biocontrol approach. The identification of antagonistic fungi able to control agents that cause major olive diseases, such as Verticillium dahliae, will benefit future biological control approaches for limiting this increasingly spreading pathogen.This work was supported by Science and Technology Foundation (Fundação para a Ciência e Tecnologia – FCT) project PTDC/AGR-AAM/102600/2008 “Entomopathogenic fungi associated to olive pests: isolation, characterization and selection for biological control”. The first author is grateful to the Science and Technology Foundation for the PhD grant SFRH/BD/44265/2008

Recorded and potential alien invertebrate pests in Finnish agriculture and horticulture

It is assumed that climate change will promote pest invasions and their establishment in new regions. We have updated the list of current alien invertebrate pest species in Finland and produced a list of potential new alien pests using a self-organizing map (SOM) that ranks species in terms of their risk of entry into Finland. The 76 pest species recorded included 66 insects, 5 nematodes, 2 mites and 3 slugs. Nearly half of the alien species appeared to have invaded Finland during the last 48 years. The SOM analysis is considered a viable tool for identification of potentially high-risk invasive pests from among the multitude of potential alien invaders, and represents a useful complement to local expert knowledge-based risk assessment of potentially invasive pests. Along with the comparisons with databases of current and potential pest species, SOM analysis suggests that in the changing climate, the habitats at greatest risk from exotic pests in Finland are horticultural: orchards, ornamental hardy-nursery stocks, landscape and ornamental tree nurseries, and greenhouses.Ilmastonmuutokset arvioidaan edistävät kasvintuhoojien leviämistä ja kotoutumista uusille maantieteellisille alueille. Tässä julkaisussa on päivitetty lista Suomessa vuoteen 2010 mennessä tavatuista vierasperäisistä selkärangattomista kasvintuhoojista sekä tuotettu ennusteet Suomesta vielä puuttuvien vierasperäisten tuhohyönteislajien kotoutumisriskin suuruudelle käyttäen neuroverkkomallinnukseen perustuvaa self-organizing map (SOM) -menetelmää ja materiaalina maailmanlaajuista tuhohyönteistietokantaa. Suomessa jo tavattuja vieras- ja tulokaskasvintuhoojalajeja on 77, joista 67 on hyönteisiä, viisi ankeroisia, kaksi punkkeja ja kolme kotiloita. Lähes puolet listan lajeista on saapunut Suomeen viimeisten 48 vuoden aikana. Ennustetut riski-indeksit vierasta alkuperää oleville kasvintuhoojahyönteisille olivat korkeita Suomeen jo saapuneille lajeille. Tämä viittaa siihen, että SOM-menetelmä on käyttökelpoinen väline rajaamaan sitä lajistoa, jonka Suomeen saapumista ja kotoutumista on syytä erityisesti seurata. Menetelmä soveltuu hyvin täydentämään asiantuntijatietoon pohjautuvia riskinarviointeja vieras- ja tulokaslajien kotoutumismahdollisuuksista Suomeen. SOM-analyysin ennusteet viittaavat siihen, että ilmaston vähitellen muuttuessa uusien kasvintuhoojien kotoutumisriski on suurin puutarhatuotannossa (hedelmätarhat, taimitarhat, puistopuut, kasvihuoneet)