Egyptian Journal of Plant Protection Research Institute

Efficacy of some volatile oils against adults of the white garden snail Theba pisana and the brown garden snail Eobania vermiculata (Gastropoda: Helicidae) and their effects on carbohydrate hydrolyzing enzyme activity

Fri, 30 May 2025 00:00:00 +0000

The objective of this study is to investigate the molluscicide impacts of some volatile oils, such as geranium oil (Pelargonium graveolens), French lavender oil (Lavandula dentate), and lemon eucalyptus oil (Corymbia citriodora), against adults of Theba pisana (Müller) and Eobania vermiculata (Müller) (Gastropoda: Helicidae) snails at concentrations (7, 14, and 28%). Then, gas chromatography (GC) is a powerful analytical technique utilized to separate, identify, and quantify components in tested volatile oils. Data showed that the maximum effect of mortality percentages was (46.67 and 40.00%) of Lemon eucalyptus oil at the highest concentration after 28 days of T. pisana and E. vermiculata snails, respectively. Furthermore, the outcomes of biochemical investigations explained that Lemon eucalyptus oil for T. pisana snails were reported (-9.69, -9.81 and -8.59%) and (-16.53, -21.37 and -23.53%) of amylase and invertase enzymes, respectively, at the highest concentration, whereas E. vermiculata snails were recorded (-9.13, -6.41 and -5.55%) and (-2.10, -2.54 and -2.61%) of the same enzymes, respectively. Finally, data mentioned that the tested oils can be categorized in declining order of their efficiency as follows: Corymbia citriodora > Lavandula dentate > Pelargonium graveolens on T. pisana followed by E. vermiculata, possibly due to differences in the size of snails.

Biologicalstudies on the efficacy of two native fungal pathogens against fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae)

A. Ibrahim Suzan, E. Lotfy Dalia, M.S. Badr Suzan — Fri, 30 May 2025 00:00:00 +0000

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), a notorious and adaptable pest, has inflicted substantial crop yield losses globally. This research investigated the potential of two native entomopathogenic fungi, Beauveria bassiana and Purpureocillium lilacinum, Isolations were conducted at the biopesticide production unit at the Plant Protection Research Institute as biocontrol agents against S. frugiperda larvae. In laboratory trials, larvae were exposed to five different concentrations of fungal spores, ranging from 1×10⁵ to 1×10⁹ spores/ml. Researchers then meticulously tracked mortality rates, larval development time, pupation rates, adult longevity, and fecundity. The study revealed a clear, dose-dependent relationship between fungal concentration and larval mortality. B. bassiana emerged as the most potent isolate, achieving an impressive 76.5% mortality within 6.1 days at the highest concentration. Both fungal isolations also significantly impacted other key life-cycle parameters, reducing larval development time, pupation rates, adult longevity, and fecundity. These promising results suggest that these entomopathogenic fungi hold considerable potential as effective biocontrol agents in the fight against S. frugiperda. Future research will focus on optimizing application strategies for these fungal biocontrol agents and rigorously evaluating their efficacy under real-world field conditions.

Mass rearing technique for predaceous Orius laevigatus (Hemiptera: Anthocoridae) in the laboratory and its efficacy on three prey species

M.S. Hammad, M.H. Mowafi, A.A. Abdallah, M.I. Hassan — Fri, 30 May 2025 00:00:00 +0000

Orius species (Hemiptera: Anthocoridae) are generalist predators of small insects, including thrips, mites, aphids, and scales. Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) can be reared successfully using a plastic Petri dish as a rearing cage with wheat grains to prevent cannibalism and excessive moisture. Frozen eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) were supplied as food, and a soybean seedling was provided as an oviposition substrate. We checked the prey preference of the predatory leaf disks containing different numbers of nymphs and adults of Thrips tabaci (Lindeman) (Thysanoptera: Thripidae), Myzus persicae (Sulzer) (Hemiptera: Aphididae), and Tetranychus urticae. Koch (Acari: Tetranychidae). In addition, the number of prey consumed was recorded, and the development stages of O. laevigatus were observed. This study aimed to examine the composition of predatory Orius laevigatus on three preys: T. tabaci, M. persicae, and T. urticae. The experiment was carried out under laboratory conditions (25±1°C and 65±5% RH.).

Histopathological effects of bacterial symbionts of entomopathogenic nematodes on the leaf miner Tuta absoluta (Lepidoptera: Gelechiidae)

Muhammad Jihan, A. M. Azazy, I. El-Kholy Ayat, D. Saleh Waleed, M. A. Ali — Fri, 30 May 2025 00:00:00 +0000

The economic impact of Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), an invasive lepidopteran pest, on global Solanum lycopersicum production is substantial, driven by its high fecundity and selection for insecticide-resistant phenotypes. Entomopathogenic nematodes (EPNs) and their symbiotic bacteria introduce an environmentally friendly protection method for tomato plants. This study intends to elucidate the histopathological alterations induced in the third larval instar of T. absoluta by bacterial symbionts associated with entomopathogenic nematodes, under controlled laboratory environments. Results demonstrated that the EPNsB and their cell-free filtrates caused significant midgut disruption, characterized by epithelial cell degeneration and apical membrane vacuolization. These alterations culminated in larval mortality through cellular lysis and compromised midgut integrity.

Context based expert system for diagnosing tomato pests

Elsayed Abdelrahman, F. Ellakwa Susan, Moawad Nevien, A.M. Azazy — Fri, 30 May 2025 00:00:00 +0000

An expert system is a decision support system for a specific domain. It has been applied in different fields. In the agriculture domain in Egypt, we have developed many systems for different crops since the late 1990s. However, those systems need to be updated to match current advances in technologies. Traditional expert systems statically interact with end users, there is a need to make it smarter to be adaptable based on user context. We utilize a context knowledge base; hence the expert system will be more intelligent by expecting user complaints. For diagnosing pests of tomatoes, we added knowledge that correlates between the current month and potential pests. So, the questions that relate to the current date will have a high rate of being asked by the grower. Also, we used weather services to get weather data and correlate it with potential pests. The result ensures that the proposed system outputs are as expected, and it displays symptoms of pests that are related to the grower context data.

Bird damage assessment and evaluation of mechanical approaches to protect crops from birds

M.A. Mohamed, M. Wilson, W.F. Soliman — Fri, 30 May 2025 00:00:00 +0000

Birds causing crop damage led to an economic problem in Egypt's agricultural. Therefore, this work aimed to determine the damage in some crops, such as wheat, barley, broad bean, sunflower, grapes, and tomato in the fields of Yousef El-Sedik, Fayoum Governorate. Moreover, some mechanical approaches (Fish net, and reflecting stripes) were evaluated. The results revealed that the birds attacked all the ripening stages of the plants except tomato and grapes, they were only damaged in the mature stage. Also, broad beans were damaged in the milky and dough stages, but there was no damage in the mature stage. Regarding the results, the investigation found that the fishnet approach was more effective and achieved 100% protection for all crops compared to the scaring approaches (Reflecting stripes). Therefore, it can be concluded that the birds caused the damage to crops in all ripening stages of crops, and fishnets achieved complete protection for the crops, but they are very expensive for the farmer and difficult to use in the mature stage in some crops, so it needs more studies to protect crops, especially at the mature stage and at the lowest costs to help farmers and solve the economic problems in agriculture.

Efficacy of some chemicals and bioinsecticides against cotton mealybug Phenacoccus solenopsis (Hemiptera: Pseudococcidae) as a new recorded pest of sugar beet in Egypt

S. Abdel-Fattah Rasha, H.M. Mokhtar Aida, H.M.A. Konper, M.F. Arafa Eman — Fri, 30 May 2025 00:00:00 +0000

Abstract The purpose of this study was to evaluate the effectiveness of chemical and bioinsecticides against the cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), which was recently found infesting sugar beet (Beta vulgaris L.) in Egypt. Lambda-cyhalothrin, mineral oil, sulfoxaflor, and Biossiana® are some of the chemical and bioinsecticides that are commonly used. Field trials were conducted over two consecutive growing seasons (2022–2023) in Kafr El-Sheikh Governorate using a randomized complete block design. Results demonstrated that lambda-cyhalothrin and sulfoxaflor achieved the highest population reductions (99.92% and 99.31%, respectively), with rapid knockdown effects attributed to their neurotoxic modes of action. Mineral oil showed delayed but significant efficacy (98.4% reduction by day 10), consistent with its physical mode of action. The biofungicide Biossiana® exhibited progressive control (96.1–99.31% reduction), with its performance linked to wax degradation and cuticular penetration. The study demonstrated that the efficacy of control measures against P. solenopsis was substantially influenced by the pest's distinctive morphological adaptations, most notably its protective wax coating and cryptic feeding behavior. These biological traits underscore the importance of adopting integrated pest management strategies that combine chemical and biological control methods. To optimize management outcomes, applications should be timed to coincide with vulnerable life stages, while treatment combinations should be employed to counteract the pest's wax-mediated resistance mechanisms. Furthermore, regular rotation of control agents is essential to maintain long-term effectiveness. This research aimed to provide crucial insights for developing sustainable management approaches against this recent pest infested sugar beet, offering solutions that balance effective control with environmental conservation.

Toxicological effect of Photorhabdus luminescens and Xenorhabdus spp. on fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera, Noctuidae) and its safety evaluation on Sprague Dawley albino rats

Muhammad Jihan, Faisal Saheir, A. El-Shiekh Tarek — Fri, 30 May 2025 00:00:00 +0000

The polyphagous lepidopteran pest Spodoptera frugiperda (J.E. Smith) (Lepidoptera, Noctuidae) (Fall armyworm), is a significant contributor to agricultural economic losses. This study investigated the insecticidal efficacy of Photorhabdus luminescens and Xenorhabdus spp. against neonate larvae of S. frugiperda. Bioassays revealed statistically significant larval mortality, evidencing potent entomotoxic effects associated with these bacterial species. The acute oral and dermal toxicity of P. luminescens (EGAP3) and Xenorhabdus spp. were evaluated in Sprague-Dawley albino rats to determine their suitability as natural agricultural materials. Throughout the experimental period, no observable adverse effects, including clinical signs, behavioral abnormalities, mortality, or pathological lesions, were detected in any of the treated animals. Additionally, all rats exhibited normal weight gain. These toxicity results suggest that P. luminescens (EGAP3) and Xenorhabdus spp., possess potential as a safe and effective biocontrol for the control of insect pests, phytopathogenic fungi, and root-knot nematodes in agricultural settings.

Population dynamics of Tetranychus urticae (Acari: Tetranychidae) and its predator Phytoseiulus persimilis on eggplant cultivars, with emphasis on vertical distribution and chemical control of this pest

A. Ibrahim Noha, M. Gaber Wafaa, Z. Aziz Wessam, A. Elshanat Heba — Fri, 30 May 2025 00:00:00 +0000

This study investigated the population dynamics, vertical distribution, varietal susceptibility, and chemical control of Tetranychus urticae Koch (Acari: Tetranychidae) on four eggplant (Solanum melongena) cultivars during two consecutive growing seasons (2023 and 2024). Seasonal population monitoring revealed higher mite densities in 2024 compared to 2023. Among the cultivars, Spherical Black had the highest infestation, peaking with 52.6 mites per leaf (28 July 2024), while Long Black showed the lowest levels, indicating some inherent resistance. Varietal susceptibility analysis revealed significant differences, with Spherical Black and Balady being the most susceptible and Long Black the least affected in both years. Vertical distribution assessments during the fruiting stage showed T. urticae preferred the lower canopy, with most of eggs, immatures, and adults concentrated in this area, emphasizing the need for targeted monitoring. Regarding the predator-prey interaction, natural predators of T. urticae, particularly Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) were observed to play an important role in controlling mite populations. Positive correlations (highly significant) between P. persimilis and T. urticae were recorded in both years, suggesting that the predator actively tracks and potentially helps in suppressing mite populations in the field. For chemical control, four acaricides, hexythiazox, fenpyroximate, bifenazate, and abamectin, were evaluated. Abamectin proved the most effective, reducing populations by over 90%, followed by fenpyroximate, bifenazate, and hexythiazox. These findings highlight the importance of integrating acaricide use with resistant cultivars for effective pest management.

Predicting the annual generations for the cucurbit fruit fly Dacus ciliatus (Loew) (Diptera: Tephitidae) under climate change

M.I. Ouda, M. Abozeid Samia, El-Sabah A. Fetoh Badr — Fri, 30 May 2025 00:00:00 +0000

The cucurbit fruit Dacus ciliatus (Loew) (Diptera: Tephritidae) is pest distribution in all Africa, Asia and Middle East on cucurbit crops. In Egypt, this study was conducted the prediction of annual generations of D. ciliatus with climate changes for 2022 and 2023 years at Qaha city, Qalyoubia Governorate. The results showed that the calculated nine D. ciliatus generations by applying the formula of Richmond et al. (1983) they: One generation in the winter: the expected generation was on 21^st of December and 23^rd of December and the observed generation was on 1^st of January and 30^th of December on cucumber crop in greenhouse for 2022 and 2023 and 2024 seasons. Two generations in the spring: the expected generation was on (21^st of March and 18^th of March) and (3^rd of May and 1^st of May) and the observed generation was on (25^th of March and 20^th of March) and (5^th of May and 6^th of May) during 2022 and 2023 seasons, respectively. Four generations in the summer they: The expected generations were on (10^th of June and 7^th of June ); (7^th of July and 1^st of July); (31^st of July and 26^th of July) and (23^rd of August and 18^th of August), the observed generations were on (15^th of June and 10^th of June ); ( 10^th of July and 5^th of July); (5^th of August and 29^th of July) and (1^st of September and 20^th of August) for first, second, three and four summer generations during 2022 and 2023 seasons, respectively. Two generations in the autumn: the expected generations were on (26^th of September and 18^th of September) and (8^th of May and 5^th of November), the observed generation were on (1^st of October and 21^st of September) and (11^th of November and 8^th of November) during 2022 and 2023 seasons, respectively. The infestation was recorded on the host plant of the squash crop in the open field for each of the spring, summer and autumn generations for the 2022 and 2023 seasons. Whereas the results indicated that there was a significant correlation between the numbers of D. ciliatus with plant age, maximum, minimum temperature and R.H.%.

The resident and migratory bird species in Fayoum Governorate, Egypt

M.A. Mohamed, M. Wilson, W.F. Soliman — Fri, 30 May 2025 00:00:00 +0000

Egypt has diverse weather throughout the year, which makes it attractive to many types of birds. So, the present study surveyed some of the resident and migratory bird species in Yousef El-Seddik district, Fayoum Governorate, Egypt, from 2018 to 2020. Birds were counted for four successive days monthly during the study period. The observed bird species were counted, identified, and classified. Also, the registered birds were divided into resident and migratory bird species. The results pointed out that there are 78 bird species belonging to 12 orders and 30 families that were recorded from 2018 to 2020. Also, the results revealed that seventeen birds were residents, while 59 birds were migratory. Finally, it was concluded that the order Passeriformes was the largest order registered in the study district, followed by Charadriiformes, followed by Ciconiiformes and Anseriformes, while the rest of the orders came in the last rank.