The peach–potato aphid, Myzus persicae (Sulzer), is one of the most important pests of economic crops. It damages the plant directly by consuming nutrients and water and indirectly by transmitting plant viruses. This pest has the unenviable title of having resistance to more insecticides than any other herbivorous insect pest. Due to the development of its resistance to chemical pesticides, it is necessary to find other control options. Consequently, increased efforts worldwide have been undertaken to develop new management approaches for M. persicae. In this review, we highlight the problems associated with the peach–potato aphid, its economic importance, and current management approaches. This review also describes the challenges with current management approaches and their potential solutions, with special focus given to the evolution of insecticidal resistance and sustainable pest management strategies, such as biocontrol agents, entomopathogens, the use of natural plant-derived compounds, and cultural methods. Furthermore, this review provides some successful approaches from the above eco-friendly pest management strategies that show high efficacy against M. persicae.
Plants use a variety of secondary metabolites to defend themselves against herbivore insects. Methyl salicylate (MeSA) is a natural plant-derived compound that has been used as a plant defence elicitor and a herbivore repellent on several crop plants. The aim of this study was to investigate the effect of MeSA treatment of Brassica rapa subsp. chinensis (‘Hanakan’ pak choi) on its interactions with peach potato aphids, Myzus persicae, and their natural enemy, Diaeretiella rapae. For this, we selected two concentrations of MeSA (75 mg/L and 100 mg/L). Our results showed that aphid performance was significantly reduced on plants treated with MeSA (100 mg/L). In a cage bioassay, the MeSA (100 mg/L)-treated plants showed lower adult survival and larviposition. Similarly, the MeSA (100 mg/L)-treated plants had a significantly lower aphid settlement in a settlement bioassay. In contrast, the M. persicae aphids did not show any significant difference between the MeSA (75 mg/L)-treated and control plants. In a parasitoid foraging bioassay, the parasitoid D. rapae also did not show any significant difference in the time spent on MeSA-treated and control plants. A volatile analysis showed that the MeSA treatment induced a significant change in volatile emissions, as high numbers of volatile compounds were detected from the MeSA-treated plants. Our results showed that MeSA has potential to induce defence in Brassica against M. persicae and can be utilised in developing sustainable approaches for the management of peach potato aphids.
Organic acid assistance is one of the effective methods for phytoremediation of heavy metal contaminated soil. In this experiment, the addition of citric and glutaric acids was selected to improve the accumulation of cadmium and lead by Helianthus annuus L. Results showed that citric and glutaric acids elevated the growth of the plants and stimulated Cd/Pb uptake by plant in single Cd/Pb treatments, but glutaric acid showed inhibitory action on the uptake of metals in complex treatments. Organic acids impacted the translocation of Cd/Pb differently, and citric acids (30 mg·L−1) enhanced the translocation of Cd to aerial parts of the plants in Cd (5 mg·kg−1) and Cd (10 mg·kg−1) plus Pb treatments. Glutaric acid (30 mg·L−1) could promote the translocation factors in the complex treatments of Cd (5 mg·kg−1) with Pb (50, 100 mg·kg−1) added. The application of citric and glutaric acid could be conducive to increase floral growth when proper doses are used, and incorporation of these organic acids can be a useful approach to assist cadmium and lead uptake by sunflower. However, growth, bioaccumulation, and translocation of metals may differ due to the metals’ property, kinds, and concentrations of organic acids.
This research evaluated the biocontrol potential of the bacterial flora from cured sugarcane bagasse (SCB) against Fusarium oxysporum f. sp. lycopersici (Fol), the causal agent of tomato Fusarium wilt. Screenings of twenty SCB-derived isolates revealed consistent antagonistic activity, inhibiting mycelial growth from 32.08% to 55.00%. The most effective isolate, 100MTN1, was identified via 16S rRNA sequencing (GenBank: PX506225) as Bacillus atrophaeus. Interaction between B. atrophaeus 100MTN1 and Fol FOLViF has revealed a distinct profile of bioactive metabolites produced specifically during co-cultivation. Transcriptomic profiling of Fol FOLViF exposure to 100MTN1 identified 189 differentially expressed genes, with downregulation of genes involved in DNA replication, translation, and membrane transport, and upregulation of those linked to secondary metabolism and oxidative stress. KEGG pathway mapping further supported the possible causes of disruptions within the pathogen. Molecular docking suggested that the B. atrophaeus 100MTN1 derived metabolite, 6-Hydroxy-3′-methoxyflavone and exhibits binding affinity for key Fol proteins that compares favorably with the commercial fungicides. Greenhouse trials using tomato cv. Kalyan confirmed that treatment with strain 100MTN1 was associated with reduced disease severity and enhanced plant growth. These findings suggest that B. atrophaeus 100MTN1 suppresses Fol FOLViF through a combination of metabolite-driven inhibition and transcriptional interference, signifying its potential as a biological control agent for managing Fusarium wilt.
20 February 2023 in The European Zoological Journal
Two new species of the Polynema group of genera (Chalcidoidea: Mymaridae), Palaeoneura razii Anwar, Zeya and Usman sp. nov. and Acmopolynema misbahae Anwar, Zeya and Usman sp. nov. are described from India. Palaeoneura razii is quite remarkable in having short axillar setae and the posterior margin of the fore wing without a distinct lobe and curve. Hence, together with another described species, P. farmani Amer and Zeya from India, this new taxon is placed in the informal farmani species group of the genus Palaeoneura. In addition, we record new country and state records for two other species, A. dilemma Triapitsyn and Berezovskiy and A. malabaricum Subba Rao, respectively. A key to the Indian genera of the Polynema group is also provided. Article LSID: http://urn:lsid:zoobank.org:pub:D844F28F-6883-4B17-B433-23D3231CE719 Species LSID: Palaeoneura razii Anwar, Zeya & Usman http://urn:lsid:zoobank.org:act:864A3309-9A66-4722-8F1C-40F32E0AAB82 Acmopolynema misbahae Anwar, Zeya & Usman http://urn:lsid:zoobank.org:act:E4721150-0824-4085-BEAD-376D7EBDE03