Abstract
Fungi in the genus Metarhizium (Hypocreales: Clavicipitaceae) are insect pathogens that can establish as endophytes and can benefit their host plant. In field experiments, we observed a positive correlation between the prevalence of M. robertsii and legume cover crops, and a negative relationship with brassicaceous cover crops and with increasing proportion of cereal rye in mixtures. Here, we report the effects of endophytic M. robertsii on three cover crop species under greenhouse conditions. We inoculated seeds of Austrian winter pea (Pisum sativum L., AWP), cereal rye (Secale cereale L.), and winter canola (Brassica napus L.) with conidia of M. robertsii to assess the effects of endophytic colonization on cover crop growth. We recovered M. robertsii from 59%, 46%, and 39% of seed-inoculated AWP, cereal rye, and canola plants, respectively. Endophytic M. robertsii significantly increased height and above-ground biomass of AWP and cereal rye but did not affect chlorophyll content of any of the cover crop species. Among inoculated plants from which we recovered M. robertsii, above-ground biomass of AWP was positively correlated with the proportion of colonized root but not leaf tissue sections. Our results suggest that winter cover crops may help to conserve Metarhizium spp. in annual cropping systems.
Highlights
Several hypocrealean entomopathogenic fungi (EPF) commonly occur in soil [1] and in addition to infecting insects directly, can exist as rhizosphere colonizers and endophytes that provide multiple benefits in agroecosystems [2,3]
When we compared among cover crop species, we found greater endophytic colonization in Austrian winter pea (AWP) than in cereal rye and canola
When colonization of leaf and root tissues were compared within a cover crop species, we found greater colonization of root tissue compared with leaf tissue of Austrian winter pea (AWP) and canola but no difference between root and leaf colonization of cereal rye
Summary
Several hypocrealean entomopathogenic fungi (EPF) commonly occur in soil [1] and in addition to infecting insects directly, can exist as rhizosphere colonizers and endophytes that provide multiple benefits in agroecosystems [2,3]. These benefits include plant growth promotion through nutrient transfers [4,5,6], plant disease suppression [7,8,9], and insect growth suppression [10,11,12]. Plant growth promoting effects associated with endophytic colonization have been observed for multiple species of Metarhizium in tomato [18], maize [10,22], soybean [23], potato [24], cassava [19]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
