Sammendrag

Reusing soil can reduce environmental impacts associated with obtaining natural fresh soil during road construction and analogous activities. However, the movement and reuse of soils can spread numerous plant diseases and pests, including propagules of weeds and invasive alien plant species. To avoid the spread of barnyardgrass in reused soil, its seeds must be killed before that soil is spread to new areas. We investigated the possibility of thermal control of barnyardgrass seeds using a prototype of a stationary soil steaming device. One Polish and four Norwegian seed populations were examined for thermal sensitivity. To mimic a natural range in seed moisture content, dried seeds were moistened for 0, 12, 24, or 48 h before steaming. To find effective soil temperatures and whether exposure duration is important, we tested target soil temperatures in the range 60 to 99 C at an exposure duration of 90 s (Experiment 1) and exposure durations of 30, 90, or 180 s with a target temperature of 99 C (Experiment 2). In a third experiment, we tested exposure durations of 90, 180, and 540 s at 99 C (Experiment 3). Obtaining target temperatures was challenging. For target temperatures of 60, 70, 80, and 99 C, the actual temperatures obtained were 59 to 69, 74 to 76, 77 to 83, and 94 to 99 C, respectively. After steaming treatments, seed germination was followed for 28 d in a greenhouse. Maximum soil temperature affected seed germination, but exposure duration did not. Seed premoistening was of influence but varied among temperatures and populations. The relationships between maximum soil temperature and seed germination were described by a common dose–response function. Seed germination was reduced by 50% when the maximum soil temperature reached 62 to 68 C and 90% at 76 to 86 C. For total weed control, 94 C was required in four populations, whereas 79 C was sufficient in one Norwegian population.

Sammendrag

Eradication of alien invasive species in the soil with steam as an alternative to chemical fumigation may allow contaminated soil to be reused. We have investigated steam disinfestation of soil to combat invasive plant species in three experiments including different temperatures and exposure durations using a prototype stationary soil-steaming device. The experiments included effects on seed germination of bigleaf lupine (Lupinus polyphyllus Lindl.), ornamental jewelweed (Impatiens glandulifera Royle), and wild oat (Avena fatua L.; one population from Poland and one from Norway), as well as effects on sprouting rhizome fragments of Canada goldenrod (Solidago canadensis L.) and Bohemian knotweed (Reynoutria x bohemica Chrtek & Chrtková). In Experiment 1, we tested four different soil temperatures of 64, 75, 79, and 98 C with an exposure duration of 90 s. In Experiments 2 and 3, we tested exposure durations of 30, 90, and 180 s and 90, 180, and 540 s, respectively, at 98 C. Seed pretreatment of 14 d cooling for L. polyphyllus and I. glandulifera, no seed pretreatment and 12-h moistening for A. fatua populations, and 5- and 10-cm cutting size for R. x bohemica were applied. Our results showed germination/sprouting was inhibited at 75 C for I. glandulifera (for 90 s) and 98 C for the other species; however, longer exposure duration was needed for L. polyphyllus. While 30 s at 98 C was enough to kill A. fatua seeds and S. canadensis and R. x bohemica rhizome fragments, 180-s exposure duration was needed to kill L. polyphyllus seeds. The results showed promising control levels of invasive plant propagules in contaminated soil by steaming, supporting the steam treatment method as a potential way of disinfecting soil to prevent dispersal of invasive species.

DSC01016-Bioimmigrants1

Divisjon for bioteknologi og plantehelse

BIOIMMIGRANTS - Innovative metoder og ny teknologi for identifikasjon og bekjempelse av invaderende fremmede arter og dørstokkarter som truer biobasert produksjon


Det er en sterk økning i introduksjon og etablering av nye planteskadegjørere og andre invaderende fremmede arter til nye land og regioner. Dette ser primært ut til å være forårsaket av økt internasjonal handel og import av planter, planteprodukter og jord. Klimaforandringene er med på å tilrettelegge for at de introduserte artene kan etablere seg i nye klimatiske områder.

Aktiv Sist oppdatert: 24.04.2021
Slutt: des 2022
Start: jan 2018
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Divisjon for bioteknologi og plantehelse

RessursRetur – Ny vanndampteknologi omdanner biologisk forurensede jordmasser og planteavfall til nye ressurser


Bærekraftig bruk og vern av naturressurser er et viktig prinsipp i den sirkulære bioøkonomien. Flytting av jord fra utbyggings- og samferdselsprosjekter til nye areal og utnyttelse av planteavfall til gjødsel eller jordforbedring kan bidra til at ressurser gjenbrukes godt. Ved utbygging av veier, jernbane og eiendom går i dag mye dyrkbar jord tapt fordi jorda ofte inneholder uønskede organismer som det er forbudt å spre. Eksempler på uønskede organismer eller "biologisk forurensing" er åkerugress slik som floghavre, fremmede plantearter som kjempespringfrø, sykdomsfremkallende sopp som løkhvitråte, og planteparasittære nematoder som potetcystenematode og rotgallnematode. Planteavfall fra produksjon og import av grønnsaker er også uutnyttede ressurser på grunn av risiko for innhold og spredning av farlige planteskadegjørere.

Aktiv Sist oppdatert: 15.12.2021
Slutt: mars 2025
Start: apr 2021