Phthorimaea Operculella Research Articles

A New-Designed Light Trap for the Control of Potato Tuber Moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), in Stored Potatoes

A New-Designed Light Trap for the Control of Potato Tuber Moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), in Stored Potatoes

Heat stress affects potato's volatile emissions that mediate agronomically important trophic interactions.

Potato, a cool-weather crop, emits volatile organic compounds (VOCs) which attract the specialist herbivore, Phthorimaea operculella, but also this herbivore's parasitic wasp, Trichogramma chilonis, an important biocontrol agent. What happens to this trophic system when heat stress challenges this agro-ecosystem? We studied how high temperature (HT) pre-treatments influence potato's VOC emissions and their subsequent effects on the preferences of insects, as evaluated in oviposition assays and Y-tube olfactometers. HT pre-stressed plants were less attractive to P. operculella adult moths, which were repelled by HT VOCs, but increased the recruitment of the parasitoid, T. chilonis, which were attracted. VOC emissions, including the most abundant constituent, ß-caryophyllene, were enhanced by HT treatments; some constituents elicited stronger behavioural responses than others. Transcripts of many genes in the biosynthetic pathways of these VOCs were significantly enhanced by HT treatment, suggesting increases in de novo biosynthesis. HT increased the plant's stomatal apertures, and exogenous applications of the hormone, ABA, known to suppress stomatal apertures, reduced leaf volatile emissions and affected the HT-altered plant attractions to both insects. From these results, we infer that HT stress affects this plant-insect interaction through its influence on VOC emissions, potentially decreasing herbivore ovipositions while increasing ovipositions of the parasitoid.

Front Cover Image, Volume 78, Issue 9

The cover image is based on the Research Article Potato plant variety affects the performance and oviposition preference of Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae) by Mengdi Zhang et al., https://doi.org/10.1002/ps.6625. Image Credit: Yulin Gao.image

Surveillance for potato tuber moth, Phthorimaea operculella Zeller (Lepidoptera: Gelichiidae) in Kolar and Chikkaballapur district of Karnataka

Potato tuber moth (PTM), Phthorimaea operculella Zeller has become one of the most serious insect pests of potato (Solanum tuberosum L.) around the world, including in India. Field studies were conducted against PTM in Rabi seasons during 2019-20 in four and two taluks of Kolar and Chikkaballapur districts of Karnataka, respectively to understand the extent of foliage damage and leaf mines. Mean per cent infestation of PTM and number of mined leaves per plant during Rabi season of survey were highest with 4.47% and 8.31 mined leaves in Kolar district and it was least in Chikkaballpur district (2.51% and 2.95), respectively. Number of mines per plant was observed lowest (5.09) in Kolar district compared to Chikkaballapur district with 5.24 mines per plant. The above damage parameters like per cent PTM infestation and number of mined leaves per plant were not differed significantly whereas number of mines per plant was significantly different in Chikkaballapur district. On the other hand, all the damage parameters were significantly differed in Kolar districts during the survey in Rabi season 2019-20. In recent years, the temperature has been steadily rising due to climate change, and it is predicted that the occurrence of the PTM will continue to increase in the future. Therefore, the development of control technologies and intensive monitoring will be necessary for stable potato production as well as potato post-harvest.

Repellency and insecticidal activities of Thapsia garganica crude extract against some important pests

Repellency and insecticidal activities of Thapsia garganica leaf methanolic extract were investigated against Tribolium castaneum, Myzus persicae, Phthorimaea operculella, and Spodoptera littoralis. Repellency and toxic activities (by ingestion and topical application) were evaluated on T. castaneum nymphs and adults. Topical application treatment caused total larval growth inhibition at 10%, until mortality after 7 days. The highest mortality was recorded with 94% at the same concentration. Methanolic extracts incorporation into T. castaneum larvae artificial diet at 10% caused 100% mortality after 3 days. The extract at 1% cause high repellent effect on T. castaneum after 60 min of exposure, while M. persicae was less sensitive. P. operculella female’s showed sensitivity by a repellent effect at oviposition. Egg’s number laid on treated tubers at 1% and 2% decreased significantly to 32% and 72%, respectively. In addition, methanolic extracts had a preventive effect on P. operculella larval penetration. In fact, the number of larvae was reduced by 30.46% and 76.12% in the treated tubers at 1% and 2%, respectively. For S. littoralis, a low antifeeding effect was recorded. However, the relative growth rate (RGR), conversion of ingested and digested food to biomass, were decreased. The approximate digestibility increased. Moreover, a delay in larval development was observed. This study suggests that the leaf extract of T. garganica could be applied as bio-insecticide.

Evaluation of the Egg Predator Blattisocius tarsalis (Mesostigmata: Blattisociidae) for the Biological Control of the Potato Tuber Moth Tecia solanivora under Storage Conditions

Tecia solanivora is the most prevalent pest causing damage to potato crops in fields in the Canary Islands, but even more so in the postharvest storage period. However, currently, there are no authorised chemical insecticides for potato storage facilities. Analysis of the viability of the predator mite Blattisocius tarsalis as a biological control agent for this moth was carried out. A study of the temperature effect showed B. tarsalis maintains predatory capacity in the range of 10–27 °C. Though predatory activity increases with temperature, no differences in mortality rates were observed between 10 and 20 °C (33.52 ± 2.44 and 40.14 ± 3.54% efficacy rate, respectively), nor between 25 and 27 °C (59.26 ± 4.59 and 75.19 ± 4.64% efficacy rate, respectively). Under microcosm conditions, at low pest infestation (10 eggs), B. tarsalis achieved the highest mortality of eggs at a density of 5 mites, with an efficacy rate of 91.67 ± 8.33%. At high infestation levels (50 eggs), maximum mortality was achieved with a density of 10 mites and efficacy of 98.52 ± 1.48%. The choice-assay showed no preference of B. tarsalis between T. solanivora and Phthorimaea operculella, suggesting this mite could be useful in mixed infestations of potato moths. The results show B. tarsalis is a very good candidate as a control agent in storage conditions and even in mixed infestations of T. solanivora and P. operculella.

Disentangling the Potato Tuber Moth-Induced Early-Defense Response by Simulated Herbivory in Potato Plants.

Plants rely on the perception of a multitude of herbivory-associated cues (HACs) to activate their defense response to insect herbivores. These stimuli are mainly derived from three functional components, namely, mechanical damage, insect-associated microbe, and insect’s chemical cues. While simulated herbivory integrating these stimuli is widely exploited for complementing actual herbivory in clarifying the details of plant–herbivore interaction, breaking down these stimuli and identifying the mechanisms of plant responses associated with them have been less explored. In this study, the components of potato tuber moth (Phthorimaea operculella, PTM) herbivory were reorganized in a cumulative way and their impacts on the early defense responses of potato leaf were characterized. We found that simulated and actual herbivory of PTM triggered similar patterns of phytohormonal and transcriptomic responses in potato leaf. Moreover, the microbe in the PTM herbivory stimuli is associated with the regulation of the phytohormones jasmonic acid (JA) and abscisic acid (ABA) since reducing the microbe in HAC could reduce JA while increasing ABA. In addition, seven robust gene modules were identified to illustrate how potato plants respond to different PTM herbivory stimuli when herbivory components increased. Significantly, we found that mechanical damage mainly activated JA-mediated signaling; PTM-derived HACs contributed much more to potato early-defense response and induced signaling molecules such as multiple protein kinases; orally secreted bacteria stimuli could antagonize PTM-derived HACs and modulate plant defense, including repressing phenylpropanoid biosynthesis. Our study broadened the understanding of how potato plants integrate the responses to a multitude of stimuli upon PTM herbivory and evidenced that insect-associated microbes greatly modulated the plants response to insect herbivory.

Establishment of Beauveria bassiana as a fungal endophyte in potato plants and its virulence against potato tuber moth, Phthorimaea operculella (Lepidoptera: Gelechiidae).

The potato tuber moth, Phthorimaea operculella, is the most damaging potato pest in the world and is difficult to control as the larvae are internal feeders in the foliage and tubers. Entomopathogenic fungi that colonize plants as endophytes have lethal and sublethal pathological effects on insect pests. We show that Beauveria bassiana colonizes the aerial parts of potato plants endophytically after inoculation through soil drenching. Endophytic B. bassiana persisted in potato foliage for more than 50days postinoculation. Bioassays indicated that foliage of B. bassiana-inoculated potato plants were pathogenic against larvae of P. operculella. Sublethal experiments indicated that B. bassiana negatively affected the growth, development, and reproduction of P. operculella. Development experiments showed that the weight of P. operculella pupae reared on B. bassiana-colonized potato plants (4.25mg) was significantly less than that of those reared on uninoculated control plants (8.89mg). Compared with newly eclosed larvae fed on control plants, those fed on B. bassiana-inoculated plants had significantly lower survivorship, with only 17.8% developing to the adult stage. Oviposition of P. operculella females reared on B. bassiana endophytically colonized plants was significantly lower (35 eggs/female) than of those reared on uninoculated plants (115 eggs/female). This study demonstrates that endophytic B. bassiana can be a potential biological control agent for the control and management of P. operculella. Comparing pupal weights of P. operculella reared on potato plants inoculated with the B. bassiana strain GZGY-1-3 and on untreated control plants, pupae from the control plants were significantly heavier than those from treated plants.

Glutamicibacter halophytocola-mediated host fitness of potato tuber moth on Solanaceae crops.

The potato tuber moth (PTM), Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), is a destructive pest of Solanaceae crops worldwide. α-solanine and α-chaconine are toxic steroidal glycoalkaloids (SGAs) in Solanaceae crops and are most abundant in potatoes (Solanum tuberosum L.), accounting for more than 95% of the total SGAs. PTM grows on potatoes with a higher concentration of SGAs. Gut bacteria play an important role in the physiology and behavior of insects. To understand the role of gut bacteria of PTM in host adaptability, we isolated and identified major SGA (α-chaconine and α-solanine)-degrading gut bacteria in the gut of PTM by a selective medium and analyzed their degradability and degradation mechanism. The gut Glutamicibacter halophytocola S2 of PTM with high degradation capacity to α-solanine and α-chaconine were detected by liquid chromatography mass spectrometry (LC-MS) and identified by morphological and 16S rRNA gene sequence analysis. A gene cluster involving α-rhamnosidases, β-glucosidases, and β-galactosidases was identified by whole-genome sequencing of G. halophytocola S2. These genes had higher expression on the α-solanine medium. PTM inoculated with the isolated G. halophytocola S2 obtained higher fitness than antibiotic-treated PTM. The G. halophytocola S2 in the gut of PTM could degrade the major toxic α-solanine and α-chaconine in potatoes. This enhances the fitness of PTM feeding on potatoes with high SGA contents. The results provide a theoretical foundation for the integrated pest management of PTM and provide an effective strain for the treatment of α-solanine and α-chaconine in potato food. © 2022 Society of Chemical Industry.

Population dynamics of eight pests on different potato cultivars in southwest China

Yunnan province is most important area of potato planting in China. Meanwhile, there are many factors constraint to its developments, especially pest damage. So, eleven potato cultivars (such as Hezuo 88, Lishu 6, Qingshu 9 and Yunshu 304) of vital commercial variety in Yunnan were selected for pests investigation. The field survey of eleven potato cultivars in two cropping seasons (spring and autumn) was conducted from 2020 to 2021 in Yunnan province, China. During autumn planting season of 2020 and 2021, populations of eight insect pests including aphid, thrips, whitefly, leafhopper, potato tuber moth, tomato leaf miner, beet armyworm and cabbage moth were surveyed. All pest’s population peaked in October. Meanwhile, Qingshu 9 and Yunshu 304 has the largest population of aphid. The largest population of whitefly were reported on Hezuo 88 and Yunshu 304, respectively. The largest population of thrips were found on Hezuo 88, whereas Qingshu 9 has the lowest population of whitefly. The lowest population of aphid were observed on Lishu 6. The lowest population of thrips were found on Yunshu 304. During spring planting season of 2021, population of thrips, leafhopper and adult potato tuber moth were surveyed. The highest population was appeared in June. But there was no significant difference for the pests populations among different cultivars. These results of pests population dynamics during the cropping period would be helpful for making appropriate and sustainable pest management strategies.

Cinnamon essential oil loaded β-cyclodextrin/gum Arabic nanoparticles affecting life table parameters of potato tuber moth, Phthorimaea operculella (Zeller)

Plant essential oils are considered potential natural alternatives to chemical insecticides. However, increased degradation and evaporation of essential oils on exposure to environmental conditions may affect the bioavailability of their phytocompounds and reduce their activity as bio-insecticides. Therefore, this study aimed to formulate nanocapsules of cinnamon essential oil (CEO) by lyophilization technique using mixtures of β-cyclodextrin and gum Arabic (βCD + GA) inclusion as coating materials. By measuring life table parameters, the dry nano-formulations of CEO-βCD/GA were tested for insecticidal activity against the potato tuber moth Phthorimaea operculella (Zeller). Gas Chromatography–Mass Spectrometry analysis of CEO identified cinnamaldehyde as the major volatile, followed by benzyl alcohol with eugenol and nerol detected as minor constituents. CEO-βCD/GA particle sizes were 164.43 ± 1.27 nm and 151.36 ± 1.24 nm, with PDI values of 0.11 ± 0.00 and 0.25 ± 0.00 for 5.0 and 2.5% concentration, respectively. High percentage of encapsulation efficiency was obtained, reaching 81.53 ± 0.39 and 87.39 ± 0.31 for CEO-βCD/GA at concentrations of 2.5 and 5.0%, respectively. Higher mortality rates occurred in larvae treated with 2.5 and 5.0% CEO-βCD/GA (80, 85%, respectively) compared with 45% and 65% mortality rates recorded for 2.5 and 5.0% pure CEO, respectively. When compared to pure CEO, CEO-βCD/GA had a significant negative impact on tested population parameters of life table. Our findings revealed that nanoencapsulation of CEO by loading with βCD + GA inclusion increased its insecticidal efficacy. CEO-βCD/GA nanocapsules could be effective in P. operculella integrated pest management program.

CONDUCTING ACTIONS ON CONTROLLING THE SPREAD OF QUARANTINE PEST TYPES IN THE AGROBIOCENOSIS OF KARAKALPAKSTAN

Due to the fact that the Republic of Karakalpakstan is situated in the northern part of Uzbekistan, where the climate is sharp and the territory is extra-arid, changes of ecological factors in recent years, in the first place bringing into the decrease of the amount of plant types, yields of agricultural crops, which are being sown in the biotopes. As a result, rapid change of pest types of agricultural crops, which appear in biocenosis, was being observed. While the process of extinction of some types is appeared, there is an opportunity for rapid appearance of types, which did not exist in the past and coming into the ranks of the main pests. It is required to indicate these types of pests as inner and outer quarantine object and carrying out controlling actions in order to prevent them from spreading. Although these types of pests are appearing in the region in recent years, it can be stated as an example potato moth, which is damaging potato and tomato moth, which is the main pest of potato. Nowadays, it is an actual problem to create scientific basics of controlling actions which influence in maximum degree by defining biological peculiarities, developing dynamics, damaging degree in order to carry out effective controlling actions of the types which are spread in the agrobiocenosis.

Evaluation of Trichogramma cacaeciae (Hymenoptera: Trichogrammatidae) and Blattisocius mali (Mesostigmata: Blattisociidae) in the Post-Harvest Biological Control of the Potato Tuber Moth (Lepidoptera: Gelechiidae): Use of Sigmoid Functions

The potato tuber moth (PTM), Phthorimaea operculella, is the main potato pest in the world, having managed to adapt to a wide range of climatic conditions, and causing damage to stored tubers. The effectiveness of a biological control using the parasitoid Trichogramma cacaeciae and the predatory mite Blattisocius mali was evaluated in PTM under conditions that simulated those of tubers in storage. The number of adults found at the end of the trial was significantly higher in the control (181.75 ± 11.00 adults/container) than in treatments where B. mali (24.50 ± 7.22) or T. cacaeciae (102.00 ± 14.61) were released. The biological control’s effectiveness using the Abbot formula was 86.52% for the predator and 43.88% for the parasitoid. In addition, the PTM population data was fitted by logistic models, and the best fit was found for the simple logistic function. Using the data generated from these functions, the control efficiencies for the mite and the parasitoid were 94.85% and 73.77%, respectively. B. mali showed greater potential for being incorporated into integrated PTM management programs than T. cacaeciae. Based on logistic functions, a novel way of estimating the effectiveness of predators and parasitoids is also presented and discussed.

Entomopathogenic nematodes for control of potato tuber moth (Phthorimaea operculella [Zeller], (Lepidoptera: Gelechiidae) in infested tubers

The potato tuber moth (PTM), Phthorimaea operculella, is one of the most economically important potato pests worldwide. In the present study, the potential of Steinernema carpocapsae for controlling PTM in infested potato tubers was evaluated and compared with S. feltiae and the pyrethroid alpha-cypermethrin. The results for efficacy percentage showed that S.carpocapsae [72.52 and 65.49% for 12.6 × 106 and 6.2 × 106 infective juveniles (IJs), respectively] and S. feltiae (69.56% for 12.6 × 106 IJs) were as efficient as alpha-cypermethrin (66.76% for10 mg ai L−1). Both concentrations of alpha-cypermethrin and S. carpocapsae showed the least tuber damage with no significant differences (33.5–39.33%), while it was as high as the control (59.26%) in both concentrations of S. feltiae. The median lethal concentration (LC50) value for S. carpocapsae [5.46 (4.41–6.55) IJs per prepupa] was significantly lower than S. feltiae [8.52 (7.12-10.20) IJs per prepupa] which confirms the superiority of S. carpocapsae. These promising findings introduce S. carpocapsae as a part of the potato tuber protection programs for treating the tubers. Accordingly, EPNs can be considered as an appropriate alternative to synthetic chemicals for PTM control.

Sex Pheromones of the Potato Tuber Moth (Phthorimaea operculella).

The potato tuber moth (Phthorimaea operculella) is a major potato pest. Its sex pheromones contain two chemical structures: 4E,7Z-tridecadiene-1-ol acetate (PTM1) and 4E,7Z,10Z-tridecatriene-1-ol acetate (PTM2). Increasing global consciousness of environmental protection is driving widespread attention to the possible use of these pheromones for sustainable pest management. This review summarizes research on the structure confirmation, field application, and chemical synthesis of the sex pheromones of the potato tuber moth. An efficient synthesis strategy of the two sex pheromones is proposed.

A temperature‐dependent phenology model for Apanteles subandinus Blanchard, parasitoid of Phthorimaea operculella Zeller and Symmetrischema tangolias (Gyen)

AbstractThe 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.

Virulence and sex-dependent invasion efficiency of entomopathogenic nematodes on developmental stages of Phthorimaea operculella (Lep., Gelechidae)

• By IJs concentration established Steinernema in PTM increased. • Sex ratio of S. carpocapsae in pre-pupa was affected by IJ concentration. • An inverse relationship was recorded between penetration rate and IJs concentration. • No correlation was observed between the invasion efficiencies (IE) and LC50 values of EPNs. • Despite higher Steinernema IE into pupae, mortality was lower compared to pre-pupa. Virulence and invasion efficiency of the three entomopathogenic nematodes, Heterorhabditis bacteriophora , Steinernema carpocapsae and S. feltiae against the potato tuber moth (PTM), Phthorimaea operculella was evaluated. Also evaluated were the sex ratio of Steinernema spp. and host stages to determine if 1) the developmental stage of the host affects sex ratio of nematodes; 2) infective juveniles (IJs) concentration affects sex ratio in host developmental stages and 3) the establishment of IJs is affected by developmental stages of host. The PTM pre-pupa and pupa were exposed to IJs in filter substrate petri dish bioassays. By increasing the IJs concentrations, the number of established Steinernema spp. in both PTM stages increased and only decreased at the highest concentration. No reduction in established nematode numbers at the highest concentration was observed for H. bacteriophora . Sex ratio of S. carpocapsae in pre-pupa was affected by IJ concentration. PTM was more susceptible to Steinernema spp. than H. bacteriophora . Pre-pupa were more susceptible to S. feltiae but S. carpocapsae recorded as the most virulent EPN on pupa. Invasion efficiencies were similar for Steinernema and considerably higher than for H. bacteriophora . Despite a higher invasion efficiency of Steinernema into pupae, mortality was lower compared to pre-pupa No correlation was recorded between the invasion efficiencies of the EPNs and mortalities of PTM. The results showed that the invasion efficiency is not appropriate criterion to reflect the virulence of studied EPNs. Compared to H. bacteriophora both tested Steinernema spp. were good candidates for further studies as biocontrol agents of PTM.

Botanical pesticides, a potential ethnobotany Karo Regency to support food safety of the horticultural product

The use of plants as materials to control pests was known by traditional communities before the introduction of synthetic pesticides. The use of botanical pesticides has received important attention along with the negative impacts of using synthetic pesticides on health and environment. In the world, Indonesia is the seventh-largest country with the number of species of plant. There are estimated more than 20,000 spesies and 25 percent of them are flowering plants. This study aims to determine the effectiveness of several native plants of Karo Regency, that have the potential as botanical pesticides to control pests in horticultural crops. Botanical pesticides are made by extraction methods, and indicator plants for observing pest attacks are potatoes. The results based on the inventory and exploration at Karo Regency, there are 12 species of plants that are most often used by farmers as botanical pesticides to control pests in horticultural crops from family Meliaceae, Solanaceae, Caricaceae, Asteraceae, Poaceae, Annonaceae, Rubiaceae, Euphorbiaceae and Amaryllidaceae. Botanical pesticide significantly reduced pest attack on plants, reduced population of Myzus pesicae and Phthorimaea operculella and increase potato yield. The most effective of botanical pesticides to control pests on potato plants were tobacco leaf extract, lemongrass extract, and soursop leaf extract, respectively.

Encapsulated Clove Bud Essential Oil: A New Perspective as an Eco-Friendly Biopesticide

In this work by encapsulation technique we have synthetized three new clove bud essential oil (CEO) Emulsifiable Concentrate (EC) formulations depending on the carrier (synthetic zeolite- F-CSZ, nature zeolite- F-CNZ and gelatin- F-CG). The main idea was to develop an eco-friendly biopesticide that can find use in plant protection as an alternative to the use of conventional pesticides. By encapsulation we wanted to enable water solubility and ensure prolonged efficacy of the essential oil. Biological activity of designed CEO formulations was tested on potato tuber moth Phthorimaea operculella (fumigant mode of action), gray mold fungal pathogen Botrytis cinerea (preserver coatings), and soft rotting bacterial pathogens Pectobacterium carotovorum (subsp. carotovorum and brasiliensis) and Dickeya dianthicola (direct competition). CEO formulations evinced a prolonged action on mortality of P. operculella during the insects’ exposure to the concentration of the emulsions of 40 µL L−1 air. The mortality gradually decreased from a probability of 100% after the first 24 h to 50% after 5 days for F-CSZ or after 4 days for F-CNZ and F-CG. The most promising formulation is F-CSZ enabling activity during 14 days of exposure, while the effect of the other two formulations lasted 10 days. All three formulations produced a strong fungicidal effect against B. cinerea by preventing infection and disease development. The best efficacy was evidenced with F-CSZ (synthetic zeolite as a carrier) showing 100% efficacy when it was used even at the lowest tested concentration of active CEO (1%). The results of in vitro testing against soft rot pathogens determined the MIC value of CEO formulations to be 1% of active CEO. By this research, we present a novel perspective on the use of essential oils as an alternative, environmental biopesticide. CEO formulations can be commercially exploited as a fumigant or preserver coatings to extend the shelf life of stored products or the fresh-fruit market.

Germplasm, Breeding, and Genomics in Potato Improvement of Biotic and Abiotic Stresses Tolerance.

Potato is one of the most important food crops in the world. Late blight, viruses, soil and tuber-borne diseases, insect-pests mainly aphids, whiteflies, and potato tuber moths are the major biotic stresses affecting potato production. Potato is an irrigated and highly fertilizer-responsive crop, and therefore, heat, drought, and nutrient stresses are the key abiotic stresses. The genus Solanum is a reservoir of genetic diversity, however, a little fraction of total diversity has been utilized in potato breeding. The conventional breeding has contributed significantly to the development of potato varieties. In recent years, a tremendous progress has been achieved in the sequencing technologies from short-reads to long-reads sequence data, genomes of Solanum species (i.e., pan-genomics), bioinformatics and multi-omics platforms such as genomics, transcriptomics, proteomics, metabolomics, ionomics, and phenomics. As such, genome editing has been extensively explored as a next-generation breeding tool. With the available high-throughput genotyping facilities and tetraploid allele calling softwares, genomic selection would be a reality in potato in the near future. This mini-review covers an update on germplasm, breeding, and genomics in potato improvement for biotic and abiotic stress tolerance.