Shovon Chandra Sarkar

The tomato potato psyllid, Bactericera cockerelli, is an invasive pest in Australia, causing severe economic losses in solanaceous crop production and challenging sustainable pest management. Traditional pesticides (such as Organophosphates, Neonicotinoids groups, etc.), which have been used to manage other pests uses to control B. cockerelli, are increasingly challenged due to environmental risks and growing pest resistance, creating an urgent need for sustainable pest management alternatives. Biological control using resident generalist predators, such as ladybirds, shows promise in addressing these issues. This case study examines the potential of early dietary experience to enhance predator-prey interactions for pest control. Two ladybird species, the nonnative variegated ladybird, Hippodamia variegata, and the native transverse ladybird, Coccinella transversalis, were tested for their response to B. cockerelli after initial exposure. Results demonstrated that prior experience with B. cockerelli as prey increased the ladybirds preference and suppression of B. cockerelli populations. This training approach could improve the effectiveness of augmentative release strategies for targeting invasive pests. Information © The Authors 2025.

Plastic pollution is a pressing global challenge, with current management strategies often falling short regarding environmental impacts. As an alternative to plastic waste management approaches, the Galleria mellonella (Greater wax moth) has emerged as a potential natural agent to reduce plastic waste through its biodegradation. The G. mellonella larvae have a unique ability to consume and biodegrade various polymeric materials, including plastics, making them an eco-friendly solution to plastic waste management. This review provides a comprehensive overview of the current status of G. mellonella larvae in waste bioconversion and future perspectives in plastic waste management. Key challenges of the application of G. mellonella include its use in large-scale waste processing, economic feasibility, and environmental impact. This review highlights the potential of G. mellonella as a sustainable solution for plastic waste management and its possible integration into biorefineries for the production of valuable materials.

The soil-inhabiting predatory mite Stratiolaelaps scimitus (Womersley) (Acari: Laelapidae) and the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae) can both serve as effective biocontrol agents against the pest Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). Assuming the fungus B. bassiana does not adversely affect S. scimitus, the combined application of these 2 agents could enhance the suppression of F. occidentalis. The age-stage, 2-sex life table was used in the present study to evaluate the effects of B. bassiana strain GZGY-1-3 on S. scimitus, mediated through F. occidentalis feeding. When S. scimitus fed on the prepupae of F. occidentalis that had been exposed to the GZGY-1-3 suspension for 24 h, the developmental times of protonymph, deutonymph, and preadult mites were significantly longer and the mites' longevity and fecundity were significantly lower than mites fed on untreated F. occidentalis. The intrinsic rate of increase (r), finite rate of increase (λ) and net reproduction rate (R0) of the mite population were all significantly lower in the treatment where B. bassiana was applied compared to untreated populations. Specifically, the indirect effects of B. bassiana on S. scimitus was mediated through mite consumption of fungus-infected pupae of F. occidentalis. Our results showed that the combined application of B. bassiana and S. scimitus may pose potential risks for the simultaneous biocontrol of F. occidentalis.

The tomato potato psyllid Bactericera cockerelli (Hemiptera: Triozidae) is a significant insect pest of Solanaceae. In early 2017, it was first detected in Perth, Western Australia. The objective of this work was to identify predator species of B. cockerelli occurring in fields of Solanaceae in Western Australia. Predatory insects and arachnids were sampled using sweep netting in some of the major Solanaceae-growing regions in the south-west of Western Australia in 2021 and 2022. Several laboratory feeding trials were conducted to develop PCR primers that could detect the DNA of B. cockerelli in predators that had fed on B. cockerelli rather than on alternative diets. The primers were then used to screen predators collected from the field to identify those that had been feeding on B. cockerelli. In the two years of field sampling, the predators collected represented a broad taxonomic range. The most abundant predator was green lacewing followed by ladybirds. Further, we analysed predators belonging to seven insect taxa (one Neuroptera, two Hemiptera and four Coleoptera) for the presence of B. cockerelli DNA. We found that 45% of the individual insects from all taxa that we caught were positive for B. cockerelli DNA, and Coleopteran predators showed the highest rate of positive results. This is the first report confirming predation on invasive B. cockerelli by the resident predator community in the field in Australia.

Exogenous plant hormones regulate the agronomic and physiological performance of plants and thus can influence the abundance of insect groups. We surveyed the arthropods on flowering plants Cnidium monnieri and found that the abundance of natural enemies Propylaea japonica and Orius minutus in the plots treated with salicylic acid (SA) and indole acetic acid (IAA) was significantly increased compared with those in the clean water (control) plots. Then, we investigated the effects of spraying SA, IAA, and clean water on the population parameters of Semiaphis heraclei reared on C. monnieri. Our results from the age-stage, two-sex life table analysis revealed a significantly shorter pre-adult duration for aphids reared on SA-treated C. monnieri compared to those reared on the other two treatments. The intrinsic rate of increase, finite rate of increase, and net reproductive rate of aphids reared on SA- and IAA-treated C. monnieri were significantly higher than those of aphids reared on clean water-treated C. monnieri. The fecundity rate was higher under the SA and IAA treatments than in the control, but the difference was not significant. This improved the ability of flowering plants to attract natural enemies by providing a larger food source.

The tomato potato psyllid, Bactericera cockerelli, is an invasive pest in Australia, which can cause severe economic loss in the production of Solanaceous crops. As an invasive pest, B. cockerelli may also modify biotic interactions in Australian agricultural and native ecosystems. Resident generalist predators in an area may have the ability to utilize invasive pest species as prey but this will depend on their specific predatory behavior. The extent to which generalist predators learn from their previous dietary experience (i.e., whether they have used a particular species as prey before) and how this impacts subsequent prey choice will influence predator and prey population dynamics after invasion. In this study, one nonnative resident ladybird, Hippodamia variegata, and one native ladybird, Coccinella transversalis, were investigated. Dietary experience with B. cockerelli as a prey species significantly increased preference for the psyllid in a short term (6 h) Petri dish study where a choice of prey was given. Greater suppression of B. cockerelli populations by experienced ladybirds was also observed on glasshouse grown tomato plants. This was presumably due to altered prey recognition by experience. The result of this study suggest the potential to improve the impact of biological control agents on invasive pests by providing early life experience consuming the target species. It may prove valuable for developing improved augmentative release strategies for ladybirds to manage specific insect pest species.

The tomato potato psyllid, Bactericera cockerelli Šulc, originating from North and Central America, poses a serious threat to Solanaceae crops in Australia. This study investigates the potential of the Australian native and commercially available green lacewing, Mallada signatus Schneider, as a biological control agent for B. cockerelli. The effect of feeding on B. cockerelli on the development rate and survival, of M. signatus were evaluated. Further, a greenhouse cage study was conducted to determine the optimal density of M. signatus larvae needed to effectively control an established B. cockerelli population. In our study, the third instar larvae of M. signatus consumed over 75 B. cockerelli nymphs in 24 h. Following the introduction of M. signatus larvae to caged tomato plants, eight M. signatus larvae per caged tomato plant decreased B. cockerelli population by 64% at the end of the sampling. These results indicated M. signatus, particularly at the larval stage, is an effective biological control option for B. cockerelli, especially in greenhouse tomato cultivation. This research offers valuable insights for the Australian horticultural industry, presenting a viable, eco-friendly alternative to traditional, chemical pesticide-reliant pest management strategies.

BACKGROUND

The tomato potato psyllid, Bactericera cockerelli (Šulc) is a new invasive pest in Western Australia, which may disperse across the whole of Australia within a few years and cause significant economic losses. Chemical control is the most widely used approach to manage B. cockerelli, but insect resistance, chemical residue and effects on non-target species have become an increasing concerned. Therefore, in this study, the biocontrol potential of variegated lady beetle, Hippodamia variegata (Goeze) was investigated. The impact of utilizing B. cockerelli as a food source on the predator's development and reproduction was assessed by formulating age-stage, two sex life tables. The predatory potential of H. variegata on B. cockerelli nymphs was assessed in a closed arena and the effects of releasing H. variegata for the control of B. cockerelli were then evaluated.

RESULTS

H. variegata could successfully develop and oviposit when feeding on B. cockerelli. However, both survival and the rate of development were higher for H. variegata feeding on Myzus persicae (Sulzer) than B. cockerelli or a mixed population of B. cockerelli and M. persicae. A type II functional response was observed for H. variegata. In the greenhouse, the releases of H. variegata larvae reduced the number of B. cockerelli nymphs by up to 66% and adults by up to 59%, which positively influenced the plant chlorophyll content and biomass.

CONCLUSIONS

This study demonstrated the potential of the resident generalist predator, H. variegata as a biocontrol agent for the invasive pest, B. cockerelli, which may help improving current management strategies.

Incursion and establishment of an exotic pest may threaten natural habitats and disrupt ecosystems. On the other hand, resident natural enemies may play an important role in invasive pest control. Bactericera cockerelli, commonly known as the tomato-potato psyllid, is an exotic pest, first detected on mainland Australia in Perth, Western Australia, in early 2017. B. cockerelli causes direct damage to crops by feeding and indirectly by acting as the vector of the pathogen that causes zebra chip disease in potatoes, although the latter is not present in mainland Australia. At present, Australian growers rely on the frequent use of insecticides to control B. cockerelli, which may lead to a series of negative economic and environmental consequences. The incursion of B. cockerelli also provides a unique opportunity to develop a conservation biological control strategy through strategically targeting existing natural enemy communities. In this review, we consider opportunities to develop biological control strategies for B. cockerelli to alleviate the dependence on synthetic insecticides. We highlight the potential of existing natural enemies to contribute toward regulating populations of B. cockerelli in the field and discuss the challenges ahead to strengthen the key role they can play through conservation biological control.

The authors regret,

In the abstract, incorrect percentages for the population reduction on infested tomato plants were given in the follow sentence: “In a glasshouse trial using B. cockerelli-infested tomato plants, C. transversalis larvae reduced the population growth of B. cockerelli larvae by 66% and adults by 59% over one month, reducing loss of leaf chlorophyll and increasing plant biomass relative to controls.”

The correct sentence with the corrected percentages is “In a glasshouse trial using B. cockerelli-infested tomato plants, C. transversalis larvae reduced the population growth of B. cockerelli larvae by 41% and adults by 49% over one month, reducing loss of leaf chlorophyll and increasing plant biomass relative to controls.”

The data for the population reductions presented in Figure 3 and Table 5 are correct.

The authors would like to apologise for any inconvenience caused.