Invasive plant species can hinder the establishment and growth of native plants and impact several ecosystem properties, such as soil cover, nutrient cycling, fire regimes and hydrology. Controlling ...invasive plants is then a necessary, yet usually expensive, step towards the restoration of an ecosystem. A synthesis of literature is needed to understand variation in invasive plants' impacts and their practical control in restoration contexts, and to identify associated knowledge gaps.
We reviewed 372 articles published from 2000 to 2019 covering the control of undesirable plants (both exotic invasive and overabundant native plant species) in ecological restoration to gather information on the main plants being controlled and methods used, and considering the distribution of studies among biomes and countries grouped according to the Human Development Index (HDI).
Grasses and forbs were the most‐studied invasive plant species in restoration sites, but invasive trees were well studied in the tropics. Poaceae and Asteraceae were the most studied families of invasive plants. Non‐chemical interventions (mostly mowing and prescribed fire) were used in more than half of the reviewed studies globally, but chemical methods (mainly glyphosate spraying, used in 40% of projects using herbicides) are also common. The reviewed studies were mostly performed in countries with very high HDI. Countries with low and medium HDI used only non‐chemical methods.
Synthesis and applications. Decisions about which control method to use depend heavily on the invasive plant species' growth forms, the local economic situation where the restoration sites are located and resources available for control. More developed countries tend to use more chemical control, whereas less developed ones use mainly non‐chemical methods. Since most of the reviewed studies were performed in countries with very high HDI, we lack information from developing countries, which concentrates global hotspots for biodiversity conservation and global commitments of forest and landscape restoration.
Resumo
Plantas invasoras podem impedir o estabelecimento e o crescimento de plantas nativas e afetar diversas propriedades dos ecossistemas, como cobertura de solo, ciclagem de nutrientes, regimes de fogo e hidrologia. O controle de plantas invasoras, ainda que oneroso, é uma etapa necessária para restauração de muitos ecossistemas. Desta forma, sintetizar literatura existente sobre plantas invasoras em experimentos de restauração pode auxiliar na compreensão dos impactos e controle prático destas no contexto da restauração ecológica, bem como identificar lacunas de conhecimento.
Nós revisamos 372 artigos, publicados entre os anos 2000–2019, que contemplaram o controle de plantas invasoras (espécies exóticas invasoras ou nativas superabundantes) na restauração ecológica, para sintetizar informações sobre as principais plantas controladas e métodos de controle utilizados. As informações foram agrupadas considerando o bioma, local e Índice de Desenvolvimento Humano (IDH) onde os experimentos foram conduzidos.
Gramíneas e arbusto‐arbustivas apresentaram a maior frequência de ocorrência como plantas invasoras na restauração em todos os biomas analisados, mas espécies arbóreas invasoras foram também muito controladas nos trópicos. Poaceae e Asteraceae foram as famílias de plantas invasoras mais estudadas. Métodos de controle não químico (principalmente roçada e fogo) foram utilizados em mais da metade dos estudos revisados, porém, métodos químicos (principalmente pulverização com glifosato, usado em 40% dos projetos que usaram herbicidas) também foram comuns. A maioria dos estudos revisados foram realizados em países com IDH muito alto. Países com baixo e médio IDH utilizaram somente controle não‐químico.
Sínteses e aplicações. Decisões sobre qual método de controle utilizar dependeram do tipo de espécies invasora, da situação econômica do local onde se planeja fazer a restauração e dos recursos disponíveis. Países mais desenvolvidos tendem a usar mais métodos de controle químico, enquanto aqueles os pouco desenvolvidos utilizaram somente controle não‐químico. Como a maioria dos estudos foram realizados em países com Índice de Desenvolvimento Humano muito alto, se faz necessário mais informações acerca dos países em desenvolvimento, os quais concentram hotspots de biodiversidade para conservação e compromissos globais de restauração.
Decisions about which control method to use depend heavily on the invasive plant species' growth forms, the local economic situation where the restoration sites are located and resources available for control. More developed countries tend to use more chemical control, whereas less developed ones use mainly non‐chemical methods. Since most of the reviewed studies were performed in countries with very high Human Development Index, we lack information from developing countries, which concentrates global hotspots for biodiversity conservation and global commitments of forest and landscape restoration.
Increasing atmospheric carbon dioxide concentrations CO2 and climate change are impacting farming worldwide. Ecological weed management (EWM) principles, including use of diverse tactics already ...employed by many farmers, may assist in adapting to and mitigating climate change. We systematically reviewed the literature on EWM and climate change and here summarise practical considerations related to changing efficacy and utility of non‐chemical EWM practices. Localised changes in precipitation will affect tillage and cultivation. We expect that mulching, transplanting and some weed seedbank management strategies, which add resiliency to a weed management programme, may show increased utility in a future with more extreme and variable weather. Innovations in autonomous robotic weeding technologies and cultivation tool design show promise in helping to overcome challenges related to low and variable cultivation efficacy and traditionally slow working rates. EWM practices that help farmers achieve multiple objectives and provide benefits beyond climate change adaptation, such as financial gains, may be most advantageous, the development of which could be facilitated by interdisciplinary research and outreach efforts. Overall, we conclude that in an increasingly variable climate, farmers will have to employ a greater diversity of weed management tactics in order to spread risk and enable climate resilience through farming systems diversification.
The insecticidal potential of two natural zeolite formulations, Zeocem and Mycostop, was tested against the rice weevil Sitophilus oryzae (L.) and the sawtoothed grain beetle Oryzaephilus ...surinamensis (L.) on wheat, at the dose rates of 0.25, 0.50, 0.75, and 1 g/kg. The bioassays were carried out under laboratory conditions at three temperature levels (20, 25, and 30οC) and two relative humidity (r.h.) levels (55, 75%). Mortality was recorded after 7, 14, and 21 d of exposure and progeny production was recorded 65 d later. Complete (100%) mortality was achieved only for O. surinamensis adults with Zeocem for most temperature and r.h. combinations tested. Progeny production for this species was extremely low. In contrast, mortality for S. oryzae was much lower and did not exceed 87% after 21 days at any of the combinations tested, while progeny production was high. For O. surinamensis exposed to Mycostop, mortality after 21 days did not exceed 97% for all temperature and r.h combinations, while overall progeny production was low. Moreover, S. oryzae mortality was generally low and did not exceed 56%, while progeny production for this species was high for most temperature and r.h. combinations. Despite the fact that some general trends were evident, the effect of temperarature and r.h. in zeolite efficacy was often found inconclusive. The results of the present study illustrated the insecticidal potential of zeolites for the contol of certain stored product insect species, which requires additional investigation.
•Oryzaephilus surinamensis was more susceptible than Sitophilus oryzae to the tested zeolites.•Sitophilus oryzae mortality did not reach 100% in any of the combination tested, while progeny production was high.•Oryzaephilus surinamensis mortality reached 100 % in some treatments, while progeny production was not high.•Temperature and relative humidity did not show any specific trend in zeolite efficacy.
Ozone efficacy (approximately of 600 Mg.hr-1) was evaluated against Red Flour Beetle’s (RFB, Tribolium castium (Herbst)) eggs, larvae, pupae and adults at different temperatures (35, 40 and 45 ° C) ...and exposure times (1, 2, 4, 6, 8, 10 hours) under laboratory. The control treatments included above thermal levels without ozone at the mentioned exposure periods. The results indicated ozone effectively suppressed hatching with increasing temperature. The hatch egg rates was reduced to 0 % in the treated treatments after 10 h at 45° C. However, mortality rates of RFB were increased with maximizing of the exposure time to ozone. After 10-h exposure to ozone at the lowest temperature 35˚ C, complete mortality (100%) or few survivals of RFB were recorded in the susceptible stages (larvae and adults). Also, the complete mortality of adults and larvae resulted after an exposure to ozone at 40 ° C for 10 hours, compared than the high survival rates at the pest’s stages at 30 and 40° C, even after 10 hours of monitoring time. However the exposure time which is required to 100% mortality was decreased to 4 hours at 45 ° C, comparing to the thermal treatment only (control) which needed more time (6 h) for 100% of mortality. In conclusion, ozone application showed the efficacy on the mortality at all stages of RFB and the temperature was a potential factor enhancing the application of ozone for RFB control.
In this study we evaluated the efficacy of heat treatment on phosphine resistant and susceptible populations of stored product insects at twenty three different commercial facilities in Greece. Heat ...treatments were carried out by using special equipment, such as Therminate, TempAir and ThermoNox, applied alone or in combination. The overall temperature range was between 33 and 55 °C and the duration of the heat treatments was between 20 and 39 h. Adults of the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae), and the sawtoothed grain beetle, Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae), were used in the experiments. The field populations were collected from different storage facilities in Greece and were characterized as resistant populations by using the Detia Degesch Phosphine Tolerance Test Kit. Insect mortality was measured at the termination of each trial. Then, the vials were kept in incubator chambers at 25 °C and 65% relative humidity and 65 d later the progeny production was measured in the treated substrate. In light of our findings, in the vast majority of the cases, complete control was observed for both resistant and susceptible populations at all facilities. In general, in the few cases where survival and progeny production was recorded, there was no specific trend towards specific species or population. Overall, based on the current results, heat treatment can be used by the industry as an alternative method for the control of phosphine-resistant adults of R. dominica and O. surinamensis.
•Populations of two stored product insects with different susceptibility to phosphine were exposed to commercial heat treatments.•All populations were susceptible to heat treatments, regardless of their susceptibility to phosphine.•Heat treatment is effective against phosphine resistant populations of Rhyzopertha dominica and Oryzaephilus surinamensis.
Peppermint essential oil (EO) has been extensively tested to date in reducing stored-product insects and insects of public health concern with very promising results, while only a few studies target ...important crop pests. There is also very little information on the effects of peppermint EO on non-target organisms, especially concerning contact and gastric effects at the same time. The goal of the investigation was the determination of the effect of peppermint EO on the mortality of
Scop.; the feeding intensity and weight gain of
Say. larvae; and the mortality and voracity of non-target organism
Pallas larvae. Our research indicates promising use for the
EO against aphids and young larvae (second instars) of the Colorado potato beetle.
EO showed good insecticidal efficacy against
with LC
= 0.5442% for nymphs and 0.3768% for wingless females after 6 h. Over time, the LC
value decreased. For the second instar larvae of
, the LC
values were 0.6278%, 0.3449%, and 0.2020% after 1, 2, and 3 days of the experiment, respectively. On the other hand, older larvae (fourth instar) were characterized by significant resistance to the tested oil concentrations with LC
value = 0.7289% after 96 h.
oil (contact and gastric effects) at a concentration of 0.5% was found to be toxic to young larvae (2 and 5 days old) of
, while EO at a concentration of 1% was toxic to 8-day-old larvae. Thus, for the sake of ladybug safety, it would be advisable to use EO from
against aphids at concentrations lower than 0.5%.
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•Purpureocillium lilacinum is an effective entomopathogen of Acromyrmex lundii ants.•Inoculations with 1×106conidiaml−1 were responsible for the death of 85.6% (80.6–89.7) of the ...ants.•Inoculations with higher concentrations of P. lilacinum showed faster mortality and greater percentage of infection.•P. lilacinum has great capacity to infect ants despite high natural entomopathogen loads.•P. lilacinum was horizontally transmitted from inoculated to non-inoculated ants.
Many leaf-cutter ant species are well known pests in Latin America, including species of the genera Acromyrmex and Atta. An environmentally friendly strategy to reduce the number of leafcutter ants and avoid indiscriminate use of chemical pesticides is biological control. In this work we evaluated the effectiveness of a strain of the entomopathogen Purpureocillium lilacinum, against worker ants from six Acromyrmex lundii field colonies, after immersions in pure suspensions at a concentration of 1×106conidiaml−1. Survival of ants treated with P. lilacinum was significantly lower than that recorded in controls, and median lethal time (LT50) was 6–7days. P. lilacinum was responsible for 85.6% (80.6–89.7) of the mortality in inoculated ants, in which we found that the percentage of other entomopathogens that naturally infected ants decreased also, suggesting a good competitive capability of the fungus. Horizontal transmission to non-inoculated ants was also evidenced, given that 58.5% (41.9–64.2) of them died because of P. lilacinum. Moreover, we tested pathogenicity for three concentrations of this strain (1.0×104, 106 and 108conidiaml−1) and found a significantly faster mortality of ants and greater median percentage of infection at 108conidiaml−1 of P. lilacinum. CL50 value was 2.8×105conidiaml−1. We thus propose the use of P. lilacinum as a biological control agent of leafcutter ants in crops and plantations.
Experimental studies on invasive plant control often involve a small number of invasive plants and are conducted in a particular habitat. Moreover, different invasive plant control strategies vary ...among studies. Therefore, it is difficult to identify the best control method when considering the individual studies separately. Here, we conduct a systematic review to find a general pattern about the most widely used measures for controlling invasive plants, based on their growth habits and invaded habitats, and explore how different control strategies vary across different experimental studies. This information may guide us to improve our control efficiency. We found that herbicide application was the most preferred method for controlling invasive plants, regardless of their growth habit and habitat type. On the other hand, the selection of an appropriate non-chemical control method depended on the growth habit and habitat of the invasive plant. In the majority of experimental studies, control treatments were applied once, and the responses of invasive plants were monitored over one growing season. Based on these results, we discuss the merits and demerits of the most widely used control methods and provide recommendations for deciding on an effective control method.
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