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Lipaphis erysimi pseudobrassicae (Davis) and Myzus persicae (Sulzer) are important pests of brassica crops, causing significant yield losses on cabbage in Ghana. To inform the development of ecologically sound and sustainable pest management strategies for these pests, their biological and population growth parameters were studied on three cabbage varieties (Oxylus, Fortune, and Leadercross). The study was conducted in a screen house under ambient conditions at 30 ± 1°C and 75 ± 5% RH and 12:12 h photoperiod from September to November 2020. The parameters of the preadult developmental period, survival rates, longevity, reproduction, and life table were evaluated following the female age-specific life table. There were significant differences in the nymphal developmental time, longevity, and fecundity on the cabbage varieties for both aphid species. The highest population growth parameters, net reproductive rate (R0), intrinsic rate of increase r, and finite rate of increase (λ) were recorded on Oxylus variety for both L. e. pseudobrassicae and M. persicae. The lowest was recorded on Leadercross variety for L.e pseudobrassicae and Fortune for M. persicae. The results from this study suggest that Leadercross is a less suitable host for L. e. pseudobrassicae and Fortune for M. persicae, thus, should be considered as less susceptible varieties for use in primary pest management by small-scale farmers or as a component of an integrated pest management strategy for these pests on cabbage.

The current investigation uncovered notable variation in the host selection and bionomics of Lipaphis erysimi, alongside the induced levels of various phytochemicals in Brassica juncea cultivars. The mean generation and doubling time were significantly longer, while host preference, intrinsic and finite rates of increase, and gross and net reproductive rates were lower ( P  < 0.001) on Pusa Mustard 27, RLC 3, NRCHB 101, DRMR 150-35, Pusa Mustard 26 and Pusa Mustard 25. The cultivars viz., NRCHB 101, Pusa Mustard 25, Pusa Vijay, DRMR 150-35, RLC 3, DRMRIJ 16-38, Pusa Mustard 27, Pusa Double Zero Mustard 31 and Pusa Mustard 30 and RH 725 showed significantly greater variations in the phytochemical and enzymatic profiles, exerting greater deleterious effects on the life history parameters of L. erysimi . Regression analysis revealed that the induced amounts of total sugars, FRAP, total glucosinolates, AO, catalase and PAL contribute to 40.11 to 80.15% variation in bud preference and bionomics. Path analysis indicated a direct negative effect of total proteins, sugars, phenols, antioxidants, FRAP, glucosinolates, chlorophyll A, total chlorophyll, APX, PAL and myrosinase on the host selection and bionomics of L. erysimi , and can be used as biochemical markers for identifying aphid resistant B. juncea cultivars. Furthermore, DRMR 150-35, NRCHB 101, RLC 3, Pusa Mustard 26, RH 749 and Pusa Mustard 27 demonstrated elevated levels of induced defence compounds, leading to pronounced negative effects on the host selection and bionomics of  L. erysimi , hence can be used in  Brassica  improvement programme.

Aim: Assessment of Lipaphis erysimi incidence on different rapeseed-mustard varieties. Biology and life table study of L. erysimion variety Binoy. Methodology: Experiments were conducted at the Uttar Banga Krishi Viswavidyalaya farm during Rabi season 2019-20 and 2020-21. Aphid and coccinellid populations were monitored on seven rapeseed-mustard cultivars at weekly intervals. The incidence was correlated to meteorological conditions. Demographic factors of L. erysimi were investigated during the 1st fortnight of February for two generations on the Binoy variety in a greenhouse setting. Results: Agrani and Binoy produced the best yield despite the highest aphid infestation. Aphid population rapidly increased from 4th standard meteorological week (SMW) (flowering stage) and peaking during the 7th SMW (siliqual development stage). Different weather conditions have a substantial effect on aphid and coccinellid populations. L. erysimi's nymphal period was longer during the 2nd generation, which finished at the 7th SMW, whereas adult longevity and life cycle were longer during the 1st generation, which ended at the 6th SMW. Study on the demographic parameters showed a diminishing population rate following the 7th SMW. Interpretation: Agrani and Binoy can tolerate aphid infestation. Protective measures need to be initiated before crop flowering.

Aphids are phloem sap-sucking insects and are a serious destructive pest of several crop plants. Aphids are categorized as \"generalists\" or \"specialists\" depending on their host range. (Sulz.) is a generalist aphid with a broad host range while (Kalt.), a specialist aphid, has a narrow host range. Aphid infestation involves several sequential stages including host recognition and selection, overcoming primary plant defence barriers, feeding on phloem sap and detoxification of host defence responses. Information on the molecular basis of variations between generalist and specialist aphids with reference to the above processes is limited. In the current study, we generated transcriptome data of and from adult and nymph stages and analysed the differential expression of genes between adults of the generalist and specialist aphid and similarly, between nymphs of the two aphid species. We categorized these differentially expressed genes into nine different categories namely, chemosensation-related, plant cell wall degrading enzymes, detoxification-related, digestive enzymes, peptidases, carbohydrate-, lipid-, amino acid-metabolism and reproduction. We also identified putative effector molecules in both and from the transcriptome data. Gene expression analysis identified 7688 and 8194 differentially expressed unigenes at adult and nymph stages, respectively of and showed significantly higher levels of expression in a greater number of unigenes (5112 in adults and 5880 in nymphs) in contrast to the specialist, (2576 in adults and 2314 in nymphs) in both developmental stages. In addition, displayed a greater number (350 in adults and 331 in nymphs) of upregulated unigenes involved in important processes such as host recognition, plant cell wall degradation, detoxification, digestion and metabolism, which correlate with its dynamic and polyphagous nature in contrast to the specialist (337 in adults and 251 in nymphs). We also observed a greater number of putative effectors in (948 in adults and 283 in nymphs) than (797 in adults and 245 in nymphs). Based on our analysis, we conclude that the generalist aphid, has a more diversified and stronger arsenal of genes that influence its polyphagous feeding behaviour and effective response to plant defence mechanisms against insect-herbivory. Our study provides a compendium of such candidate genes that would be most useful in studies on aphid biology, evolution and control.

The genus Lecanicillium was established in 2001 based on the type species Lecanicillium lecani (former, Verticillium lecani ), which is an important entomopathogenic fungus. To date, more than thirty species in the genus have been reported, but much more are waiting to discover. In this study, two novel species isolated from soil in east China were identified. They differ from known closely related species primarily in sporulation structure, conidia and colony morphological characteristics, and sequence variations in the LSU , SSU , ITS, and TEF gene regions of the ribosomal DNA. Multigene phylogenetic analysis has provided strong molecular evidence supporting the classification of the strains, AH13B2 and JX15A210 within the genus Lecanicillium . The new species are formally named as follows: L. anqingense sp. nov. and L. renii sp. nov., respectively. Bioassays conducted on the greater wax moth, Galleria mellonella and crucifer aphid, Lipaphis erysimi showed that both fungal strains exhibit virulence. When treating with 1 × 10 8 spores/mL, the two strains gave mortality of > 60% and > 80% to G. mellonella and L. erysimi , respectively. Moreover, the median lethal times (LT 50 ) of L. renii JX15A210 and L. anqingense AH13B2 against G. mellonella and L. erysimi were recorded as 8.06 d and 4.18 d, and 10.63 d and 5.07 d, respectively. This research enhances the species diversity within the genus Lecanicillium and provides valuable genetic resources for the biological control of pests and the development of biocontrol agents.

Aphids shelter several bacteria that benefit them in various ways. The associates having an obligatory relationship are non-culturable, while a few of facultative associates are culturable in insect cell lines, axenic media or standard microbiology media. In the present investigation, isolation, and characterization of the culturable bacterial associates of various aphid species, viz., Rhopalosiphum maidis, Rhopalosiphum padi, Sitobion avenae, Schizaphis graminum, and Lipaphis erysimi pseudobrassicae were carried out. A total of 42 isolates were isolated using different growth media, followed by their morphological, biochemical, and molecular characterization. The isolated culturable bacterial associates were found to belong to the genera Acinetobacter, Bacillus, Brevundimonas, Cytobacillus, Fictibacillus, Planococcus, Priestia, Pseudomonas, Staphylococcus, Sutcliffiella, and Tumebacillus which were grouped under seven families of four different orders of phyla Bacillota (Firmicutes) and Pseudomonata (Proteobacteria). Symbiont–entomopathogen interaction study was also conducted, in which the quantification of colony forming units of culturable bacterial associates of entomopathogenic fungal-treated aphids led us to the assumption that the bacterial load in aphid body can be altered by the application of entomopathogens. Whereas, the mycelial growth of entomopathogens Akanthomyces lecanii and Metarhizium anisopliae was found uninhibited by the bacterial associates obtained from Sitobion avenae and Rhopalosiphum padi. Analyzing persistent aphid microflora and their interactions with entomopathogens enhances our understanding of aphid resistance. It also fosters the development of innovative solutions for agricultural pest management, highlighting the intricate dynamics of symbiotic relationships in pest management strategies.

Rapeseed-mustard, the oleiferous Brassica species are important oilseed crops cultivated all over the globe. Mustard aphid Lipaphis erysimi (L.) Kaltenbach is a major threat to the cultivation of rapeseed-mustard. Wild mustard Rorippa indica (L.) Hiern shows tolerance to mustard aphids as a nonhost and hence is an important source for the bioprospecting of potential resistance genes and defense measures to manage mustard aphids sustainably. We performed mRNA sequencing of the R. indica plant uninfested and infested by the mustard aphids, harvested at 24 hours post-infestation. Following quality control, the high-quality reads were subjected to de novo assembly of the transcriptome. As there is no genomic information available for this potential wild plant, the raw reads will be useful for further bioinformatics analysis and the sequence information of the assembled transcripts will be helpful to design primers for the characterization of specific gene sequences. In this study, we also used the generated resource to comprehensively analyse the global profile of differential gene expression in R. indica in response to infestation by mustard aphids. The functional enrichment analysis of the differentially expressed genes reveals a significant immune response and suggests the possibility of chitin-induced defense signaling.

The Zigzag ladybird beetle, Cheilomenes sexmaculata (Fabricius) (Coleoptera: Coccinellidae), is a biological control agent that feeds on a variety of aphid species. Life table and predation data of C. sexmaculata were collected under laboratory conditions at 25±2â°C, 60±5% RH and L14: D10 h in connection with feeding on four different aphid species; Lipaphis erysimi (Kaltenbach), Myzus persicae (Sulzer), Aphis nerii (Boyer de Fonscolombe) and Diuraphis noxia (Mordvilko). Larval development of C. sexmaculata was long when fed on M. persicae (12.18 days) and shorter on D. noxia (10.64 days). The male's lifespan was longer on M. persicae (26.70 days) and shorter on L. erysimi (23.67 days). Fecundity was maximum when the beetle was fed D. noxia (316.8 eggs/female) and minimum on M. persicae (199.1 eggs/female). Net reproductive rate, intrinsic rate of increase and finite rate of increase were highest on D. noxia with values of 158.4 (offspring individual.sup.-1 ), 0.22 d.sup.-1, and 1.24 d.sup.-1, respectively whereas the respective parameters were lowest on L. erysimi (99.5 offspring individual.sup.-1, 0.19 d.sup.-1, and 1.20 d.sup.-1, respectively). However, the mean of the generation (T) was shorter on A. nerii (22.48 d.sup.-1) and longer on M. persicae (24.68 d.sup.-1). Based on life table parameters obtained under laboratory conditions, the most appropriate host of C. sexmaculata was D. noxia. This study should help us to improve mass rearing and use of C. sexmaculata in the biological control of aphids on field and horticultural crops.

Background Cucumber mosaic virus (CMV) is vectored by aphids. Infection of Arabidopsis thaliana plants with CMV affects their attractiveness to aphids ( Myzus persicae ) and the performance of aphids confined on these plants. CMV-induced changes in plant-aphid interactions (‘viral manipulation’) may promote transmission. M. persicae , an efficient CMV vector is a ‘generalist’, i.e., it has many plant hosts. A. thaliana is also exploited by crucifer-specialist aphids including Lipaphis erysimi (an efficient CMV vector) and Brevicoryne brassicae (a poor CMV vector). We explored the hypothesis that CMV-induced viral manipulation of aphid behaviour would exert stronger effects on M. persicae than on crucifer-specialists. Results M. persicae , B. brassicae and L. erysimi were released in microcosms and allowed to choose to settle on either CMV-infected or mock-inoculated plants. Initial experiments showed that as systemic CMV infection developed in A. thaliana , aphids of M. persicae were decreasingly likely to settle on infected plants. In subsequent experiments, using plants at 14 days post-infection, it was found that aphids of M. persicae were faster to choose between infected and uninfected plants than specialist aphids, but that both the generalist and specialists were less likely to settle on CMV-infected plants. Olfactometry showed that volatiles emitted by CMV-infected plants attracted M. persicae , and although the specialists showed no significant preferences, greater numbers of aphids of all three species responded when CMV-infected plant volatiles were presented to them. Conclusions As CMV infection develops, A. thaliana becomes less susceptible to aphid colonisation, however, plants continue to emit attractive olfactory cues. This is consistent with a model in which aphids are attracted to infected plants but discouraged from settling (e.g., by gustatory cues), which encourages aphids to carry CMV to non-infected plants. CMV appears to be more successful in manipulating the interactions of A. thaliana with the generalist aphid M. persicae , than with the crucifer specialists B. brassicae or L. erysimi .

Aim: This study evaluates the efficacy of indigenous entomopathogenic fungal isolates against Helicoverpa armigera (Hübner) and Lipaphis erysimi (Kaltenbach) under laboratory conditions to compare the mortality rates and determine LC50 and LT50 values. Methodology: Entomopathogenic fungi were isolated using ‘Galleria bait approach’ from soil samples collected from different regions of Eastern Uttar Pradesh. The isolated entomopathogenic fungi were identified and characterized using ITS DNA primers, and their sequences were submitted in NCBI. The bio-efficacy in terms of LC50 and LT50 was determined for the pests Helicoverpa armigera and Lipaphis erysimi under laboratory conditions. Results: The findings revealed significant mortality rates, with Metarhizium anisopliae and Beauveria bassiana showing the highest efficacy against Helicoverpa armigera and Lipaphis erysimi, respectively. Interpretation: The present study revealed that the indigenous entomopathogenic fungi have high potential as biocontrol agents against Helicoverpa armigera and Lipaphis erysimi. These fungi present a promising complementary approach to chemical control methods, helping to promote more sustainable agricultural practices. Key words: Entomopathogenic fungi, Helicoverpa armigera, Lipaphis erysimi, Mortality rate