RNAi against ribosomal protein L27 gene impairs larval development in Phthorimaea operculella

The potato tuber moth (PTM) is an important pest of the potato plant and its tuber. With the expansion of its geographic range, the PTM could be potential threat to the tomato (Solanum lycopersicum L.), a congeneric species of the potato. To assess that risk, we tested larval feeding and development of PTM on leaves of five cultivated tomato varieties namely Moneymaker, Campari, Ailsa Craig, LA3475, E6203 and one wild tomato variety S. pimpinellifolium. PTM larvae accepted all tested plant leaves and developed into adults. Larval development was fastest on the Ailsa Craig variety. Pupae developed fastest on the Moneymaker variety and slowest on LA3475. Host acceptance and survival were highest on Ailsa Craig and lowest on LA3475. The significantly highest male proportion occurred on LA3475 variety. The study showed that PTM could be a potential threat to tomato cultivation which is rapidly increasing in temperate regions owing to climate change.

The potato tuber moth (PTM), Phthorimaea operculella (Zeller 1873) (Lepidoptera: Gelechiidae), is a destructive pest of stored potatoes and potato crop. Biopesticides are certain types of pesticides derived from animals, plants, and bacteria. Botanicals are especially efficient in the form of antifeedant, repellent, protectants, and growth-disrupting hormones. They are also sources of secondary metabolites that are safer than synthetic insecticides. Present research was conducted to evaluate some botanical extracts as natural local alternatives against PTM under storage conditions. Twelve different 80% ethanolic plant extracts were tested on PTM during storage condition (30 ± 2°C and 70 ± 5% RH) at a light regime of the day 10-h light and 14-h dark. Biological parameters of the pest, evidence of the potato tubers damage, and continuation of protection to the tubers were recorded. Extracts of mint, zygophyllum, coriander, arnoglosse, harmel, and solanum indicated a total inhibition of egg deposition at 2.5% concentration; also, they provided high protections to the potato tubers from the PTM infestation for about 3 months and without observations’ effect on tubers germination. Senna, colocynth, and basil reduced the number of deposited egg/female. Jasmine, geranium, and chamomile recorded a low potential on egg deposition. Basil showed the highest potency in decreasing development of larvae that hatched from eggs, therefore, reduced the number of next adult offspring (F1) and followed by jasmine and geranium. Variable levels of extracts’ protection can be arranged according to their damage evidence as follows: basil > colocynth > jasmine > geranium > senna > chamomile.

Tuber resistance can contribute to current management strategies against the potato tuber moth, Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae), in field and stored potatoes. Wild potatoes represent a potential source of novel resistance traits against the moth. We assessed resistance in three wild potato species, Solanum multiinterruptum Bitt., Solanum sparsipilum (Bitt.) Juz. & Buk., and Solanum wittmackii Bitt. against neonate and developing tuber moth larvae. All three species had high levels of resistance but accessions of S. sparsipilum and S. wittmackii were significantly more resistant. Resistance in S. multiinterruptum was generally concentrated in the tuber periderm, whereas in S. sparsipilum and S. wittmackii resistance was mainly cortex‐based. Unidentified cortex‐resistance factors in all three species reduced survival and increased larval and pupal development times, but had no apparent effects on the pupal weights of survivors. A high proportion of larvae abandoned or died within tubers of S. wittmackii, which has particularly high levels of unidentified cortex‐based defenses. Resistance decreased in S. multiinterruptum and S. sparsipilum as tubers sprouted but was more stable in S. wittmackii. Periderm‐based resistance was more stable than cortex‐based resistance in S. multiinterruptum during sprouting. In contrast, cortex‐based resistance was stable in tubers of S. wittmackii as these sprouted, and resistance may have increased on some older sprouting tubers. Solanum multiinterruptum and S. sparsipilum are proposed as potential sources of resistance against the potato tuber moth.

Histopathology and effect on development of the PhopGV on larvae of the potato tubermoth, Phthorimaea operculella (Lepidoptera: Gelechiidae)

The trichome‐bearing wild potatoes Solanum berthaultii (Hawkes) and Solanum tarijense (Hawkes) (Solanaceae) have noted resistance to leaf‐feeding insect herbivores; however, little is known about their resistance to tuber‐feeding herbivores. This study evaluates resistance in tubers of these two species to attack by the potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae). Tubers from a range of accessions were presented to recently emerged neonate tuber moth larvae. Resistance to neonates varied between accessions and was generally higher in accessions of S. tarijense. The contribution to observed resistance of periderm vs. cortex factors was assessed by perforating tuber periderm in paired‐tuber experiments. Across species and accessions, an average of 62% of resistance was attributed to periderm‐related factors. All larvae entered tubers through the eyes. Unidentified cortex‐related factors affected larval development time and pupal weight. Sprouting compromised resistance by reducing the protective value of the periderm. The degree of sprouting also decreased larval development times and increased pupal weights in one of two accessions examined. These results demonstrate the potential of S. berthaultii and S. tarijense as sources of tuber‐resistance and identify accessions of both species with notably high periderm‐based protection. Levels of periderm resistance were not correlated to levels of cortex resistance and represent an independent resistance source compatible with the food value of crop potato.

The extensive reliance on synthetic pesticides has led to considerable ecological disruption and negative impacts on non-target organisms worldwide. As a sustainable alternative, nanotechnology offers promising avenues for the development of innovative and environmentally safe biopesticides. In this study, the insecticidal efficacy of ethanol and silver nanoparticles (AgNPs) extracts derived from Lantana camara L. was evaluated against the eggs and larvae of the Potato Tuber Moth (Phthorimaea operculella [Zeller, 1873]), a quarantine pest of major concern in potato production in Türkiye. Toxicological assessments revealed dose-dependent larvae mortality, with LC₅₀–LC₉₀ values ranging from 6.49–51.45 ppm for ethanol extracts and 1.47–5.88 ppm for AgNPs formulations. Maximum inhibition of egg hatching was observed at 12% ethanol extract (86.51%) and 200 ppm AgNPs treatment (94.95%). Bioassay results demonstrated that AgNPs formulations of L. camara were significantly more effective than ethanol extracts in suppressing both larval and egg development. Moreover, potato tubers treated with AgNPs exhibited a pronounced reduction in adult moth emergence compared to untreated controls. Collectively, these findings highlight the potential of L. camara nano-silver extracts as a sustainable biopesticide candidate for integrated management of P. operculella.

Simple SummaryQuantitative real-time fluorescent polymerase chain reaction (qRT-PCR) is a momentous tool for calculating the expression levels of targeted genes across various experimental conditions. The selection and evaluation of stable reference genes for qRT-PCR analysis is an essential precondition for reliable expression assessment. Phthorimaea operculella is one of the most serious Lepidopteran pests that attack potatoes around the world. In the present paper, a total of 10 commonly used reference genes, namely ACT, α-TUB, 18S, 28S, GAPDH, EF1α, RPL4, RPL13, RPL27 and SOD, were selected and validated for suitability under three treatments (developmental stages, tissues/organs and temperatures) using five methods (Ct value, geNorm, NormFinder, BestKeeper and RefFinder). These results indicated that EF1α and RPL13 were the best suitable reference genes for diverse backgrounds. The relative transcript levels of the target gene chitin synthase A gene (PoChSA) were abundantly expressed in epidermal cells, and lowly transcribed in the midgut. Our findings will be beneficial for improving the accuracy of qRT-PCR analysis for future functional analysis of the target gene expression in P. operculella.Due to a lack of effective internal references, studies on functional genes in Phthorimaea operculella, a serious Lepidopteran pest attacking potatoes worldwide, have been greatly limited. To select suitable endogenous controls, ten housekeeping genes of actin (ACT), α-tubulin (α-TUB), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), elongation factor 1α (EF1α), 18S and 28S ribosomal RNA (18S, 28S), ribosomal protein genes RPL4, RPL13 and RPL27 and superoxide dismutase (SOD) were tested. Their expression levels were determined under three different experimental conditions (developmental stages, tissues/organs and temperatures) using qRT-PCR technology. The stability was evaluated with five methods (Ct value, geNorm, NormFinder, BestKeeper and RefFinder). The results clarified that RPL13, EF1α and RPL27 are ranked as the best reference gene combination for measuring gene expression levels among different developing stages and under various temperatures; EF1α and RPL13 are recommended to normalize the gene expression levels among diverse tissues. EF1α and RPL13 are the best reference genes in all the experimental conditions. To validate the utility of the selected reference pair, EF1α and RPL13, we estimated the tissue-biased expression level of chitin synthase A gene (PoChSA). As expected, PoChSA was abundantly expressed in ectodermally derived epidermal cells, and lowly transcribed in the midgut. These findings will lay the foundation for future research on the molecular physiology and biochemistry of P. operculella.

Biological implications of somatic DDX41 p.R525H mutation in acute myeloid leukemia.

48] Temperature-sensitive mutants with alterations in ribosomal protein L24 and isolation of intra- and extragenic suppressor mutants

Predator-derived chemical cues suppress pest reproduction through non-consumptive pathways and may be exploitable as semiochemicals in integrated pest management. We evaluated the volatile organic compounds (VOCs) emitted by the predatory mite Pyemotes zhonghuajia, for their inhibitory effects on reproduction in the potato tuber moth (Phthorimaea operculella, PTM). Screening of 34 mite-associated VOCs identified dimethyl trisulfide (DMTS) as the strongest oviposition suppressor. In dose-response assays, DMTS reduced egg-laying (>80% at 0.9 mg mL-1), shortened the oviposition period (from 5.09 to 1.86 days at 0.9 mg mL-1) and decreased female longevity (from 13.48 to 4.80 days), but did not affect the pre-oviposition period. DMTS exposure also lowered mating frequency without affecting copulation duration, thereby compounding fecundity reduction. Offspring from exposed parents hatched slightly earlier (4.00 versus 4.32 days), showed prolonged larval development (14.44 versus 13.61 days), and exhibited higher food consumption (1.66 versus 0.83 g). Ovarian dissections revealed fewer mature oocytes, consistent with inhibited oocyte maturation. DMTS disrupts PTM reproduction by suppressing oviposition and mating, and inhibiting ovarian maturation, with additional, modest carry-over effects on offspring development. These findings support DMTS as a promising predator-derived semiochemical for sustainable PTM management. © 2026 Society of Chemical Industry.

Morphological and microstructural properties of silica (SiO2) are essential factors that need to be considered during the experimental applications. In this report, SiO2 nanoparticles (NPs) have been prepared at different concentrations from SiO2 powder derived from olive stones and corncobs by an alkali leaching extraction method. Thermal treatment has been used to modify the morphological and microstructural properties of the extracted SiO2. X-ray diffraction (XRD) shows that the extracted amorphous SiO2 has been transformed into a crystalline phase after the thermal treatment. Nitrogen adsorption–desorption measurements revealed significant reduction in both the specific surface area (SABET) and the total pores volume (Vtotal) of the derived SiO2 samples after the thermal treatment. The acquired thermal treatment properties of SiO2 found to have high impacts on the influence of the SiO2 NPs on the survival and development of larvae and pupae of P. opercullela. SiO2 NPs prepared from the crystalline silica samples exhibited less efficiency on suppressing potato tuber moth comparing to SiO2 NPs of the amorphous silica powders. Varied effects on biological parameters including larvae mortality, pupae weight, larval and pupal development time, fecundity and fertility are also linked to the SiO2 NPs source type and showed concentration depending manner effects. SiO2 NPs are conditionally effective as an alternative pesticide against P. opercullela, based on their sources, mesoporous structures and concentrations.

Host fidelity in phytophagous insects can arise from both genetic constraints and behavioral plasticity, with consequences for host specialization. The preference–performance hypothesis predicts that females should oviposit on hosts that maximize offspring fitness, yet the extent to which host fidelity and host quality jointly shape oviposition preference is not fully understood. For host fidelity to be an adaptive pattern, it should be relaxed in scenarios of low‐quality hosts. We used the potato tuber moth Phthorimaea operculella (PTM) to test if fidelity to a given host depends on its quality as larval host. First, PTM larvae were reared on seven potato ( Solanum tuberosum ) varieties differing in dry matter content. We measured performance parameters, including larval stage duration, pupal weight, and pupal survival. We found variation in PTM performance across potato varieties, which was aligned with the varieties dry matter content. Larval development was fastest and pupal numbers highest on the high‐dry matter (starchy) varieties, while pupal weight varied among varieties and did not consistently align with host quality. Based on the performance results, we chose one potato variety representing each of three categories of host quality: low (waxy), high (starchy) and intermediate (waxy‐starchy). Second, we evaluated in a four‐port olfactometer the oviposition preference of gravid females reared on each of those three varieties of different quality, having as alternative choices the same three varieties plus a control variety. Females reared on high‐quality and intermediate‐quality varieties strongly preferred their rearing host, that is, showed host fidelity. In contrasts, those females reared on a low‐quality variety showed no preference. Results show that host fidelity in PTM is conditional on host quality and shaped by developmental experience, supporting the preference–performance hypothesis when hosts are of relatively high quality only. Our findings have implications for the evolution of host specialization in insects and PTM management.

The potato tuber moth (Phthorimaea operculella Zeller) is a major invasive pest of potato (Solanum tuberosum L.) worldwide. Classical biological control using parasitoids had been of primary interest during the last decades to control this pest. More than twenty parasitoid species have been reported parasitizing P. operculella. Apanteles subandinus Blanchard had been successfully used in different countries. Determination of the parasitoid's temperature‐dependent development is crucial for better predicting the potential of the parasitoid to establish in a new region and to control the target pest. Therefore, the effect of temperature on the development and reproduction of A. subandinus was studied at five constant temperatures ranging from 11–30°C in its main host P. operculella. The Insect Life Cycle Modeling (ILCYM) software was used to fit nonlinear equations to collected life table data and to establish an overall phenology model to simulate life table parameters based on temperature. The parasitoid completed its life cycle at constant temperatures from 15 to 30°C. Temperature of 11°C was lethal to pupae, and at 35°C no larvae development was possible. The theoretical lower threshold temperatures for the development of egg‐larvae and pupae were 10.3°C and 11.8°C respectively. The model predicted limits for survival at around 12°C and 33°C. The lowest senescence rate was observed within the temperature range of 15–25°C. Oviposition time decreased significantly with increasing temperature from 12.2 days (15°C) to 1.8 days (30°C). The highest fertility was predicted at 27°C. Maximum population growth is expected around 26.78°C with a finite rate of increase, λ of 1.0445, which corresponds to a population doubling time of 15.9 days. The highest values for gross reproduction rate (GRR) and net reproduction rate (R0) were found between 24 and 25°C, and the shortest mean generation time (T) was observed at 30°C (23.48 d). The use of the phenology model in the context of classical biological control of P. operculella is discussed.

The occurrence and mechanism of plant resistance to some pests were studied on potato ( Solanum tuberosum) cultivars Achat, Aracy, Itarar and Apu and on the hybrids N 140-201 and NYL 235-4 from S. tuberosum x S. berthaultii. Myzus persicae ( green peach aphid) was evaluated in the greenhouse and in field plots. Liriomyza huidobrensis (leaf miner) and soil insects were evaluated in field plots Phthorimaea opercullela (potato tuber moth) was evaluated in the laboratory, in the rang of 24 to 27 C and photophase of 14 hours, on potato tuber. The clones N 140-201 and NYL 235-4 were susceptible to attack of the green peach aphid, while the cultivars Aracy and Achat showed field resistance (antixenosis) to this pest. All clones from S. tuberosum and the hybrids N 140-201 and NYL 235-4 did not show resistance in the grenhouse. The cul ti vars Itarar and Apu showed resistance (antixenosis) for alimentation of L. huidobrensis, while the hybrids N 140-XV 201 and NYL 235-4 did not show deterrent action for alimentation. In the field, the clones N 140-201 and NYL 235-4 showed resistance to tuber damage. The sarne resul ts were observed for potato tuber moth in the laboratory experiment. Antibiosis was the mechanism of resistance to P. operculella, increasing larval mortality rate and development time.

because we included samples from children hospitalized with or without respiratory disease.