Planococcus notacanthi sp. nov., isolated from the skin of a deep-sea snub-nosed spiny eel.

A novel bacterial strain, APC 4016T, was previously isolated from the skin of a snub-nosed spiny eel, Notacanthus chemnitzii, from a depth of 1000 m in the northern Atlantic Ocean. Cells were aerobic, cocci, motile, Gram-positive to Gram-variable staining, and gave rise to orange-pigmented colonies. Growth occurred at 4-40 °C (optimum, 25-28 °C), pH 5.5-12 (optimum, pH 7-7.5), and 0-12 % (w/v) NaCl (optimum, 1 %). 16S rRNA gene phylogenetic analysis confirmed that strain APC 4016T belonged to the genus Planococcus and was most closely related to Planococcus okeanokoites IFO 12536T (98.98 % 16S similarity). However, digital DNA-DNA hybridization and average nucleotide identity values between these two strains were low, at 20.1 and 83.8 %, respectively. Major (>10 %) cellular fatty acids of strain APC 4016T were iso-C14 : 0, anteiso-C15 : 0 and C16 : 1-ω-Alc. The predominant respiratory quinones were menaquinones 5, 6, 7 and 8. The major cellular polar lipids were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine, and three unknown lipids were also present. The draft genome sequence is 3.6 Mb with a G+C content of 45.25 mol%. This strain was previously shown to have antimicrobial activity and to encode bacteriocin and secondary metabolite biosynthetic gene clusters. Based on the phylogenetic analysis and its distinct phenotypic characteristics, strain APC 4016T is deemed to represent a novel species of the genus Planococcus, and for which the name Planococcus notacanthi sp. nov. is proposed. The type strain of this species is APC 4016T (=DSM 115753T=NCIMB 15463T).

Identification of a receptor for the sex pheromone of the vine mealybug, Planococcus ficus.

The vine mealybug, Planococcus ficus, is a significant pest of vineyards in all major grape growing regions of the world. This pest causes significant aesthetic damage to berry clusters through its feeding behavior and secretion of "honeydew", which leads to significant decreases in crop marketability. More importantly, the vine mealybug is a vector of several grapevine viruses which are the causal agent of grapevine leafroll disease, one of the most destructive and economically devastating diseases of the grape industry worldwide. As there is no cure for grapevine leafroll disease, the only control measures available to reduce its spread are to remove infected vines whilst simultaneously controlling mealybug populations. Using transcriptomic libraries prepared from male and female mealybugs and a draft genome, we identified and evaluated expression levels of members of the odorant receptor gene family. Interestingly, of the 50 odorant receptors identified from these P. ficus genetic resources, only 23 were found to be expressed in females, suggesting this flightless life stage has a decreased reliance on the olfactory system. In contrast, 46 odorant receptors were found to be expressed in the alate male life stage. Heterologous expression of eight of these receptors, along with the obligate co-receptor, Orco, in HEK293 cells allowed for the identification of two receptors that respond to lavandulyl senecioate, the sole constituent of the sex pheromone used by this species. Interestingly, one of these receptors, PficOR8, also responded to the sex pheromone used by the Japanese mealybug, Planococcus kraunhiae. The data presented here represent the first report of odorant receptor gene family expression levels, as well as the identification of the first sex pheromone receptor, in soft-scale insects. The identification of a receptor for the vine mealybug sex pheromone will allow for the development of novel, species-specific pest control tools and monitoring devices.

Draft genome sequence of Planococcus sp. SK3692.

Whole-genome sequencing was performed for a Planococcus sp. isolate. This bacterium was of interest because of its vibrant orange pigmentation.

Unraveling the draft genome and phylogenomic analysis of a multidrug-resistant Planococcus sp. NCCP-2050T: a promising novel bacteria from Pakistan.

Planococcus is a genus of Gram-positive bacteria known for potential industrial and agricultural applications. Here, we report the first draft genome sequence and phylogenomic analysis of a CRISPR-carrying, multidrug-resistant, novel candidate Planococcus sp. NCCP-2050T isolated from agricultural soil in Pakistan. The strain NCCP-2050T exhibited significant resistance to various classes of antibiotics, including fluoroquinolones (i.e., ciprofloxacin, levofloxacin, ofloxacin, moxifloxacin, and bacitracin), cephalosporins (cefotaxime, ceftazidime, cefoperazone), rifamycins (rifampicin), macrolides (erythromycin), and glycopeptides (vancomycin). Planococcus sp. NCCP-2050T consists of genome size of 3,463,905 bp, comprised of 3639 annotated genes, including 82 carbohydrate-active enzyme genes and 39 secondary metabolite genes. The genome also contained 80 antibiotic resistance, 162 virulence, and 305 pathogen-host interaction genes along with two CRISPR arrays. Based on phylogenomic analysis, digital DNA-DNA hybridization, and average nucleotide identity values (i.e., 35.4 and 88.5%, respectively) it was suggested that strain NCCP-2050T might represent a potential new species within the genus Planococcus. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03748-z.

Development of a Concurrent Treatment Technique of Ethyl Formate and Mixtures (Nitrogen, Phosphine) to Control Citrus Mealybug (Planococcus citri).

Currently, the fumigant ethyl formate (EF) is stored as a liquified gas in metal cylinders mixed with carbon dioxide (CO2), but this product type is expensive to manufacture, transport, and maintain in cylinders. To address these problems, we developed a new EF fumigation technique with a nitrogen (N2) carrier. In this report, the susceptibility of citrus mealybugs, one of the most resistant mealybugs to fumigants, to EF was assessed; the phytotoxicity of an EF + N2 concurrent treatment applied to banana fruit was examined to evaluate the efficacy compared to the current EF + CO2 product; and the increased efficacy with a phosphine (PH3) addition to EF + N2 was also assessed. Concurrent treatment of EF and N2 was performed at an LC50 concentration of EF. N2 was applied in seven doses from concentrations of 79% to 95%. The phytotoxicity of EF to bananas was assessed by applying EF at 35 mg/L with N2 at 79%, and the color, sugar content, and weight loss of bananas were measured for 14 days after treatment. The EF with N2 treatment resulted in more than 50% mortality at all growth stages of the mealybug, and there was no significant difference between the untreated and treated banana fruits. EF mixed with PH3 showed a higher efficacy than treatment with EF alone, but only a slight increase in efficacy was observed when the PH3 concentration increased. These results indicate that concurrent treatment with EF and N2 can be used to control mealybugs on banana fruits, and combined treatment with EF and PH3 can also enhance the efficacy against mealybugs.

The structure, characterization and immunomodulatory potential of exopolysaccharide produced by Planococcus rifietoensis AP-5 from deep-sea sediments of the Northwest Pacific.

Polysaccharides derived from microorganisms exhibit diverse structures and bioactivities, making them promising candidates for the treatment of various diseases. However, marine-derived polysaccharides and their activities are relatively little known. In this work, fifteen marine strains were isolated from surface sediments in the Northwest Pacific Ocean for screening of EPS production. Planococcus rifietoensis AP-5 produced a maximum yield of EPS at 4.80 g/L. The purified EPS (referred to as PPS) had a molecular weight of 51,062 Da and contained amino, hydroxyl, and carbonyl groups as its major functional groups. PPS primarily consisted of →3)-α-D-Galp-(1 â†’ 4)-α-D-Manp-(1 â†’ 2)-α-D-Manp-(1 â†’ 4)-α-D-Manp-(1 â†’ 4,6)-α-D-Glcp-(1 â†’ 6)-ß-D-Galp-(1→, with a branch consisting of T-ß-D-Glcp-(1→. Additionally, surface morphology of PPS was hollow, porous, and sphere-like stack. PPS primarily contained C, N, and O elements, with a surface area of 33.76 m2/g, a pore volume of 0.13 cc/g, and a pore diameter of 1.69 nm, respectively. Based on the TG curve, the degradation temperature of PPS was measured to be 247 °C. Furthermore, PPS demonstrated immunomodulatory activity through dose-dependently upregulating the expression level of cytokines. It significantly enhanced the cytokine secretion at a concentration of 5 µg/mL. To sum up, this study offers valuable insights for screening marine polysaccharide-based immunomodulators.

A Novel Insect Overwintering Strategy: The Case of Mealybugs.

Insects have limited ability to regulate their body temperature and have thus required a range of strategies to withstand thermally stressful environments. Under unfavorable winter conditions, insects often take refuge under the soil surface to survive. Here, the mealybug insect family was selected for the study. Field experiments were performed in fruit orchards in eastern Spain. We used specifically designed floor sampling methods combined with fruit tree canopy pheromone traps. We found that in temperate climates, the large majority of the mealybugs move from the tree canopy to the roots during the winter, where they turn into belowground root-feeding herbivores to survive and continue underground the reproductive process. Within the rhizosphere, mealybugs complete at least one generation before emerging on the soil surface. The preferred area to overwinter is within 1 m in diameter around the fruit tree trunk, where more than 12,000 mealybug flying males per square meter can emerge every spring. This overwintering pattern has not previously been reported for any other group of insects showing cold avoidance behavior. These findings have implications at the winter ecology level but also at the agronomical level since treatments to control mealybug pests are, until now, only based on the fruit trees' canopy.

Two novel Planococcus species isolated from baijiu pit mud with potential application in brewing.

Two novel Gram-positive bacteria, designated strains REN8T and REN14T, were isolated from baijiu pit mud in Sichuan Province, China. REN8T achieved the best growth at 37°C, a pH of 8.0, and a NaCl concentration of 2%, while REN14T displayed optimal growth at 37°C, a pH of 6.0, and a NaCl concentration of 1%. 16S rRNA and genomic phylogenetic analysis showed that REN8T and REN14T were clustered with the genus Planococcus. The genomic DNA G + C contents of REN8T and REN14T were 46.7 and 45.1 mol%, respectively. The dDDH and ANI values were 24.5 and 80.43% between REN8T and P. salinarum (the most closely related type strain) and 25.1 and 82.42% between REN14T and P. soli (the most closely related type strain). Genomic analysis showed that several carbohydrate-active enzymes and secondary metabolite gene clusters existed in REN8T and REN14T. Chemotaxonomic characteristics of REN8T and REN14T included major fatty acids, predominant menaquinones, and polar lipids, all of which were consistent with the genus Planococcus. Based on the polyphasic taxonomic method, these two strains represent two novel species of the genus Planococcus; the name Planococcus beigongshangi sp. nov. is proposed for the type strain REN8T (=JCM 33964T = GDMCC 1.2213T), and the name Planococcus beijingensis sp. nov. is proposed for the type strain REN14T (=JCM 34410T = GDMCC 1.2209T). The addition of REN8T and REN14T might improve the quality of huangjiu by considerably increasing the amino acid nitrogen content and acidity and decreasing the bioamine content, with no significant change in alcohol content.

Characterization of a novel cold-adapted intracellular serine protease from the extremophile Planococcus halocryophilus Or1.

The enzymes of microorganisms that live in cold environments must be able to function at ambient temperatures. Cold-adapted enzymes generally have less ordered structures that convey a higher catalytic rate, but at the cost of lower thermodynamic stability. In this study, we characterized P355, a novel intracellular subtilisin protease (ISP) derived from the genome of Planococcus halocryophilus Or1, which is a bacterium metabolically active down to -25°C. P355's stability and activity at varying pH values, temperatures, and salt concentrations, as well as its temperature-dependent kinetics, were determined and compared to an uncharacterized thermophilic ISP (T0099) from Parageobacillus thermoglucosidasius, a previously characterized ISP (T0034) from Planococcus sp. AW02J18, and Subtilisin Carlsberg (SC). The results showed that P355 was the most heat-labile of these enzymes, closely followed by T0034. P355 and T0034 exhibited catalytic constants (k cat ) that were much higher than those of T0099 and SC. Thus, both P355 and T0034 demonstrate the characteristics of the stability-activity trade-off that has been widely observed in cold-adapted proteases.

Novel ß-Carotene and Astaxanthin-Producing Marine Planococcus sp.: Insights into Carotenogenesis Regulation and Genetic Aspects.

Astaxanthin and ß-carotene are the most prominent carotenoids extensively used in pharmaceutics. Here, we present a halotolerant bacterium from Lake Wadi El-Natrun capable of producing astaxanthin and ß-carotene analyzed by HPLC, ESI-MS, and infrared spectroscopy. The phenotypic and phylogenetic analyses classified the isolate as a novel strain of the genus Planococcus, for which the name Planococcus sp. Eg-Natrun is proposed. Carotenoid biosynthesis can exceptionally occur in a light-inducible or constitutive manner. The maximum carotenoid yields were 610 ± 13 µg/g (~ 38% ß-carotene and ~ 21% astaxanthin) in a minimal medium with acetate and 1024 ± 53 µg/g dry cells in a rich marine medium. The carotenogenesis incentives (e.g., acetate) and disincentives (e.g., methomyl) were discussed. Moreover, we successfully isolated the CrtE gene, one of the astaxanthin biosynthesis genes, from the unknown genome using a consensus-based degenerate PCR approach. To our knowledge, this is the first report elucidating astaxanthin and ß-carotene in the genus Planococcus.

Novel viral RNA genomes of the vine mealybug Planococcus ficus.

The vine mealybug, Planococcus ficus (Signoret, 1875), is the most important insect pest in growing areas of the grapevine Vitis vinifera L. in several countries, including Mexico. In Mexico, Baja California (B.C.) is the region with the highest production of V. vinifera L. grapes for industrial purposes. Recently, the diversity of viruses infecting insects only (insect-specific viruses) has been broadly explored to elucidate further ecological viral-host interactions in many insect species, which in some cases has resulted in the application of virus-based biological control agents for insect pests. However, a survey of the Pl. ficus virome has not been done yet. In the present study, we pooled Pl. ficus individuals collected through different vineyards of Ensenada, B.C., Mexico and analysed them by meta-transcriptomics. Novel nearly complete genomes of five RNA viruses were retrieved. These viruses were related to the Iflaviridae and Reoviridae families, and to the Picornavirales and Tolivirales orders. A new isolate belonging to the Dicistroviridae family was also found. Phylogenetic analyses showed that these putative viral genomes group with viruses having hemipteran (including a mealybug species) or other insect hosts, or with viruses associated with insects. Our results suggest that the identified novel RNA viruses could be insect-specific viruses of Pl. ficus. This work is the first insight into the Pl. ficus virome; it guarantees further studies aimed to characterize those viruses with potential for application in biological control of this economically important insect.

Genomic insights revealed the environmental adaptability of Planococcus halotolerans Y50 isolated from petroleum-contaminated soil on the Qinghai-Tibet Plateau.

The Tibetan Plateau niche provides unprecedented opportunities to find microbes that are functional and commercial significance. The present study investigated the physiological and genomic characteristics of Planococcus halotolerans Y50 that was isolated from a petroleum-contaminated soil sample from the Qinghai-Tibet Plateau, and it displayed psychrotolerant, antiradiation, and oil-degraded characteristics. Whole genome sequencing indicated that strain Y50 has a 3.52 Mb genome and 44.7% G + C content, and it possesses 3377 CDSs. The presence of a wide range of UV damage repair genes uvrX and uvsE, DNA repair genes radA and recN, superoxide dismutase, peroxiredoxin and dioxygenase genes provided the genomic basis for the adaptation of the plateau environment polluted by petroleum. Related experiments also verified that the Y50 strain could degrade n-alkanes from C11-C23, and approximately 30% of the total petroleum at 25 °C within 7 days. Meanwhile, strain Y50 could withstand 5 × 103 J/m2 UVC and 10 KGy gamma ray radiation, and it had strong antioxidant and high radical scavengers for superoxide anion, hydroxyl radical and DPPH. In addition, pan-genome analysis and horizontal gene transfers revealed that strains with different niches have obtained various genes through horizontal gene transfer in the process of evolution, and the more similar their geographical locations, the more similar their members are genetically and ecologically. In conclusion, P. halotolerans Y50 possesses high potential of applications in the bioremediation of alpine hydrocarbons contaminated environment.

Isolation, characterization and degradation performance of oxytetracycline degrading bacterium Planococcus sp. strain pw2.

Oxytetracycline (OTC), is a widely used veterinary antibiotic for treatment and prophylaxis in aquaculture. As an emerging pollutant, OTC in the environment exerts selective pressure on aquatic organisms causing proliferation of antibiotic resistant genes. In the present study, an OTC tolerant isolate labelled as pw2 was selected among the 11 OTC tolerant isolates, isolated from the aquaculture effluent, for investigating its OTC degrading potential. The cell morphology, biochemical characteristics, and 16S ribosomal RNA (rRNA) gene sequence of the isolated strain indicated that it belonged to the genus Planococcus. The OTC removal percentage was estimated through measuring its residual concentration in the culture medium with high performance liquid chromatography. The strain exhibited maximum removal efficiency of 90.62%, with initial OTC concentration of 10 µg/ml. The optimum degrading conditions were 35 °C and pH 7. The degradation rate of OTC with (biotic) and without strain pw2 (abiotic) was 3.253 and 1.149 mg/l/d, respectively. The half-life was recorded to be 2.13 d in the presence of strain pw2, in contrast to 6.03 days recorded without strain pw2. The total (biotic + abiotic) OTC degradation efficiency was 75.74, 83.93, 90.62, and 86.47% for the initial OTC concentrations of 1 to 25 µg/ml, respectively. Addition of carbon and nitrogen did not influence the OTC removal which indicates Planococcus sp. pw2 use OTC as sole energy source. Thus, Planococcus sp. pw2 plays a vital role in reducing the OTC concentration in the environment, offering a promising method for treatment of aquaculture effluent containing OTC.

Planococcus maritimu ML1206 Strain Enhances Stress Resistance and Extends the Lifespan in Caenorhabditis elegans via FOXO/DAF-16.

The antioxidant effect of probiotics has been widely recognized across the world, which is of great significance in food, medicine, and aquaculture. There are abundant marine microbial resources in the ocean, which provide a new space for humans to explore new probiotics. Previously, we reported on the anti-infective effects of Planococcus maritimu ML1206, a potential marine probiotic. The antioxidant activity of ML1206 in C. elegans was studied in this paper. The study showed that ML1206 could improve the ability of nematodes to resist oxidative stress and effectively prolong their lifespan. The results confirmed that ML1206 could significantly increase the activities of CAT and GSH-PX, and reduce the accumulation of reactive oxygen species (ROS) in nematodes under oxidative stress conditions. In addition, ML1206 promoted DAF-16 transfer to the nucleus and upregulated the expression of sod-3, hsp-16.2, and ctl-2, which are downstream antioxidant-related genes of DAF-16. Furthermore, the expression of the SOD-3::GFP and HSP-16.2::GFP was significantly higher in the transgenic strains fed with ML1206 than that in the control group fed with OP50, with or without stress. In summary, these findings suggest that ML1206 is a novel marine probiotic with an antioxidant function that stimulates nematodes to improve their defense abilities against oxidative stress and prolong the lifespan by regulating the translocation of FOXO/DAF-16. Therefore, ML1206 may be explored as a potential dietary supplement in aquaculture and for anti-aging and antioxidant purposes.

Vapor heat treatment against Planococcus lilacinus Cockerell (Hemiptera:Pseudococcidae) on dragon fruit.

BACKGROUND: The coffee mealybug Planococcus lilacinus Cockerell, is an invasive pest that infests dragon fruit [Selenicereus undatus (Haworth) D.R. Hunt], that may require a phytosanitary treatment to meet quarantine requirements. In this study, vapor heat treatment was conducted to disinfest P. lilacinus on dragon fruit and the quality of dragon fruit was evaluated thereafter. RESULTS: Adult female P. lilacinus was the most heat-tolerant stage at 47, 48 and 49 °C. The death kinetic model and probit model were used to predict LT99.9968 at the three temperatures. The treatment times predicted by the kinetic model that could effectively disinfest adult female P. lilacinus females were 120.84, 78.06 and 67.96 min at 47, 48 and 49 °C, respectively. In a confirmatory test of vapor heat treatment at 49 °C for 70 min, complete mortality was recorded for 33 195 adult females infesting 148 dragon fruits; thus, the efficacy level of disinfestation was 99.9910% at 95% confidence level. The quality of dragon fruit generally was not affected by heat treatment, fruit firmness was increased remarkably and respiration rate was significantly decreased. CONCLUSION: Our result indicates that vapor heat treatment at 49 °C for a duration of 70 min is an effective phytosanitary treatment for control of P. lilacinus on dragon fruit that minimally impacts fruit quality. © 2021 Society of Chemical Industry.

Ethyl Formate as a Methyl Bromide Alternative for Fumigation of Citrus: Efficacy, Fruit Quality, and Workplace Safety.

Ethyl formate (EF) was evaluated as a potential alternative to methyl bromide (MB) for phytosanitary treatment of imported citrus fruit in the Republic of Korea. Planococcus citri (Risso) (Hemiptera: Pseudococcidae), a mealybug with known tolerance against EF and MB, was used as a representative pest to test efficacy of the two fumigants against eggs. In nine commercial-scale refrigerated container (67.5 m3) trials using imported orange, lemon and grapefruit, EF applied at the currently approved dose for citrus (70 g·m-3 at 5°C for 4 h, developed for Aspidiotus excisus Green (Hemiptera: Diaspididae), a species less EF tolerant than P. citri) resulted in 76.9-98.3% mortality of P. citri eggs. The EF treatment did not affect the sugar content or the color of peel and pulp of the treated fruit. When oranges were treated according to the current MB (64 g·m-3 at >5°C for 2 h) or EF treatment guidelines, the concentration of fumigant around the fruit fluctuated between 9.4 and 185.1 ppm for EF and 9.5-203.0 ppm for MB during the 72-h post-fumigation processes (venting [0-2 h], transportation to storage [2-24 h], and storage periods [24-72 h]) with both EF and MB maintained between 10 and 100 ppm during the storage period. Considering the efficacy of EF, its apparent lack of phytotoxicity, and its more manageable threshold limit value for humans (100 ppm EF compared to 1 ppm MB for an 8-h time weighted average exposure), our results suggest that EF may be a promising alternative to MB for the phytosanitary treatment of imported citrus in Korea.

Pheromone Deployment Strategies for Mating Disruption of a Vineyard Mealybug.

The mealybug, Planococcus ficus (Signoret), is a primary vineyard pest in California and other grape-growing regions throughout the World. Mating disruption programs are commercially available to manage Pl. ficus, but widespread adoption has been limited, in part, by high costs compared with insecticide programs. To improve mating disruption economic effectiveness, different deployment technologies (passive, aerosol, and microencapsulated formulations) were individually examined. Adult male Pl. ficus captures in pheromone traps and categorical ratings of vine infestation or crop damage suggest that all deployment strategies lowered mealybug densities or damage. Using passive dispensers, deployment rates of 310 and 465 per ha lowered Pl. ficus crop damage similar to 615 per ha, a rate commonly used in commercial operations; reduced rates would lower product and deployment costs. Meso dispensers, containing more a.i., deployed at 35 per ha did not have a treatment impact, but a microencapsulated formulation and aerosol canisters lowered male flight captures and/or crop damage. Male mealybug flight activity was greatest from 0500-1100 hr, which coincided with temperatures >16° and <32°C. These restricted times and temperatures suggest programable dispensers might allow pheromone deployment to coincide only with flight patterns. A large field trial using passive dispensers found greater treatment separation after 3 yr of pheromone deployment. Discrepancies in results among vineyards may be related to Pl. ficus density, but combined results from all trials suggest that different deployment technologies can be used to impact Pl. ficus densities and damage, even at reduced rates, especially with continued use over multiple seasons.

Whole genome sequencing and comparative genomic analyses of Planococcus alpniumensis MSAK28401T, a new species isolated from Antarctic krill.

BACKGROUND: Extremophiles have attracted much attention in the last few decades, as they possess different properties by producing certain useful metabolites. However, the secondary metabolism of the extremophiles of Antarctic krill has received little attention. RESULTS: In this study, a new bacterial strain MSAK28401T from Antarctic krill was isolated and identified. The results of analysis on phenotypic, chemotaxonomic, and genomic characteristics showed that the strain MSAK28401T belongs to the genus Planococcus. Cells of this strain were coccoid (0.89-1.05 µm) and aerobic. The majority of the fatty acid content was C15:0 anteiso (37.67 ± 0.90%) followed by C16:1 ω7c alcohol (10.37 ± 1.22%) and C16:0 iso (9.36 ± 0.71%). The calculated average nucleotide identity and DNA-DNA hybridization values between the strain MSAK28401T and type strains P. citreus DSM 20549T and P. rifietoensis M8T were lower than 91 and 70%, respectively. The strain MSAK28401T (=KCTC 43283T and MCCC 1k05448T) represented a new member of the genus Planococcus and was named P. alpniumensis sp. nov. Moreover, genes involved in the degradation of aromatic compounds (e.g., salicylate, gentisate, and quinate) were found in the genome, implying that strain MSAK28401T has an aromatic compound as its potential metabolite. This work will help us understand the genomic characteristics and potential metabolic pathway of Planococcus from Antarctic krill. CONCLUSIONS: This study reported the genomic information and phenotypic characteristics of the new strain P. alpniumensis MSAK28401T isolated from Antarctic krill, and provided the genome information of Planococcus strains for further studying the function roles in aromatic compound metabolism.

Planococcus soli sp. nov., isolated from antarctic soil.

A novel bacterial strain, designated C23T, was isolated from a soil sample obtained from King George Island, Antarctica. Phenotypic, phylogenetic, chemotaxonomic and molecular analyses were performed on the new isolate. Strain C23T formed orange colonies on agar plates and was Gram-stain-positive. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain C23T was a member of the genus Planococcus and was closely related to Planococcus salinarum DSM 23802T (98.5% sequence similarity), Planococcus halotolerans SCU63T (98.3%), Planomicrobium okeanokoites IFO 12526T (98.3%), Planococcus donghaensis DSM 22276T (98.3%) and Planococcus maitriensisi S1T (98.2%). This organism grew at 2-38 °C (optimum, 25-30 °C), pH 6.0-12.0 (optimum, pH 7.5) and 0-14% (w/v) NaCl (optimum, 2%). The predominant menaquinone was MK-8. The major cellular fatty acids were anteiso-C15:0, iso-C14:0 and C16:1 ω7c alcohol. The whole genome DNA of C23T was deposited in the GenBank database under accession number WXYN00000000. According to the whole genome, the DNA G + C content of strain C23T was determined to be 46.8 mol%; the average nucleotide identity (ANI) of strain C23T and P. salinarum DSM 23802T, P. halotolerans SCU63T, P. okeanokoites IFO 12526T, P. donghaensis DSM 22276T and P. maitriensis S1T were 74.1%, 74.3%, 74.1%, 78.8 and 73.6%; the digital DNA-DNA hybridization (dDDH) values between strain C23T and the five closely related species were 19.7%, 19.6%, 19.5%, 22.4 and 18.6%; the average amino acid identity (AAI) values between strain C23T and the five closely related species were 73.9%, 74.5%, 74.4%, 84.6 and 74.5%. All data were below the threshold range for species determination. Based on the polyphasic taxonomic study, we considered that strain C23T represented a novel species of the genus Planococcus for which the name Planococcus soli sp. nov. is proposed. The type strain is C23T (= KCTC 33644T = CGMCC 1.15115T).

Old Parasitoids for New Mealybugs: Host Location Behavior and Parasitization Efficacy of Anagyrus vladimiri on Pseudococcus comstocki.

The Comstock mealybug, Pseudococcus comstocki (Hemiptera: Pseudococcidae) is a primary pest of orchards in the North and Northwest of China. This pest appeared recently in Europe, including Italy, where it is infesting mainly vineyards as well as apple and pear orchards. The present study investigated the efficacy of Anagyrus vladimiri, a known biological control agent (BCA) of Planococcus ficus, on P. comstocki to evaluate a potential use for the management of this new pest. No-choice tests were conducted to quantify the parasitoid behavior against P. ficus and P. comstocki. The parasitoid successfully parasitized both species (parasitization rate: 51% and 67% on P. comstocki and P. ficus, respectively). The A.vladimiri developmental time (19.67 ± 1.12 vs. 19.70 ± 1.07 days), sex ratio (1.16 ± 1.12 vs. 1.58 ± 1.07) and hind tibia length of the progeny showed no differences when P. comstocki and P. ficus, respectively, were exploited as hosts. Two-choice tests, conducted by providing the parasitoid with a mixed population of P. ficus and P. comstocki, showed no host preference for either of the two mealybug species (23 vs. 27 first choices on P. comstocki and P. ficus, respectively). The parasitization rate (61.5% and 64.5% in P. comstocki and P. ficus, respectively) did not differ between the two hosts. Overall, our study adds basic knowledge on parasitoid behavior and host preferences and confirms the use of this economically important encyrtid species as an effective BCA against the invasive Comstock mealybug.