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Objectives: Pomegranate (Punica granatum L.) is frequently affected by fungal infections during the pre-and post-harvesting periods, resulting in severe losses to the farming economy. The common pre-and post-harvest pomegranate pathogens affecting the final yield and quality of the fruits are Botrytis cinerea, Alternaria alternata, Penicillium implicatum, and Aspergillus niger. This study aimed to isolate and identify the pathogens causing pomegranate rot diseases. Also, the values of Xanthium strumarium extracts as eco-friendly control agents and three Trichoderma strains as biological control agents against the pomegranate fungal pathogen were determined. Methods: The plate dilution method was used to isolate fungi populations from pomegranate plants. The pathogens fungi were identified by the morphological and molecular method by sequenced of internal transcript spacer (ITS) region. The antifungal activities of X. strumarium extracted either by both ethanol or methanol and Trichoderma were investigated. Results and conclusions: The isolated and identified pathogens were P. implicatum, A. alternata, A. niger, Fusarium oxysporum, and F. chlamydosporum. The obtained sequences of these fungi were deposited in NCBI gene bank with accession numbers OK562113–OK562125. The efficiency of X. strumarium extract against pomegranate fungal pathogens ranged from 40.32 to 69.53% for ethanol extract and from 44.40 to 70.28% for methanol extract compared to 44.43%–85.71% for the antifungal Nystatin. Moreover, the efficiency of Trichoderma was 42.22%–72.50%, 42.30%–70.21%, and 44.54%–72.50% for strains ABSA-16, TSA-17, and ABSA-18, respectively. It could be concluded that the isolated pomegranate's pathogenic fungi in Taif were P. implicatum, A. alternata, A. niger, F. oxysporum, and F. chlamydosporum. The extract of X. strumarium obtained from the Taif region and Trichoderma can successfully assist control the pomegranate's pathogenic fungi at pre-and post-harvest, and hence can be successfully included in the IPM programs.

Objective: Trichogramma species are minute endoparasitoids of insect eggs that are considered one of the most efficient natural enemies due to their vital role against lepidopteran pests. This experiment was achieved to evaluate the effect of the emergence time of T. evanescens (Westwood) on the emergence rate, % females, % males, sex ratio, longevity, and the emergence of first generation (F1). Methods: Mass rearing of Sitotroga cerealella and T. evanecsens was performed and the previous parameters were investigated throughout an emergence period extended to 16 hrs. Results and conclusion: The emergence time has a clear impact on the tested biological parameters. The highest values of % emergence of T. evanecsens was obtained at the 7th hrs of emergence. The female percentage increased gradually to achieve the highest rate (63.58%) at the 3rd hrs, then it declined gradually to record the lowest rate (50.00%) at the 15th hrs and 16th hrs of emergence. A significant decrease in the female numbers was started after 8th hrs. There were significant negative correlations between the emerging time and each of emergence percentages and the % female. There was a negative correlation between the emerging time and longevity of T. evanescens. The longevity was 3.06 days for the parasitoid wasp adults emerged at the 1st hr and enhanced to be 3.19 days at the 3rd hrs. Also, there was a negative correlation between the emerging time and the emerging percentages of F1. Finally, the impact of developmental time on the fitness of female wasps proposes that the high quality of T. evanescens could be enlarged by enhancing the percentage of the individuals emerging early at the 7th hrs of emergence.

The pink stem borer (PSB), Sesamia cretica (Lepidoptera: Noctuidae) purple-lined borer (PLB), Chilo agamemnon (Lepidoptera: Crambidae) and European corn borer Ostrinia nubilalis, (Lepidoptera: Crambidae) are considered the most devastating insect pests of maize production in the Mediterranean region. The frequent use of chemical insecticides has resulted in the evolution of resistance to various insect pests as well as the pernicious impact on natural enemies and environmental hazardousness. Therefore, developing resistant and high-yielding hybrids is the best economic and environmental approach to cope with these destructive insects. Accordingly, the objective of the study was to estimate the combining ability of maize inbred lines (ILs), identify promising hybrids, determine gene action controlling agronomic traits and resistance to PSB and PLB, and investigate inter-relationships among evaluated traits. A half-diallel mating design was employed to cross seven diverse maize inbreds to generate 21 F1 hybrids. The developed F1 hybrids, alongside high-yielding commercial check hybrid (SC-132), were assessed in field trials for two years under natural infestation. Substantial variations were obtained among the evaluated hybrids for all recorded characteristics. The non-additive gene action was major for grain yield and its contributing traits, while the additive gene action was more important in controlling the inheritance of PSB and PLB resistance. The inbred line IL1 was identified to be a good combiner for earliness and developing short-stature genotypes. Additionally, IL6 and IL7 were recognized as excellent combiners to enhance resistance to PSB, PLB and grain yield. The hybrid combinations IL1×IL6, IL3×IL6, and IL3×IL7 were determined to be excellent specific combiners for resistance to PSB, PLB and grain yield. Strong positive associations were identified among grain yield, its related traits, and resistance to PSB and PLB. This implies their importance as useful traits for indirect selection for improving grain yield. Otherwise, the resistance against PSB and PLB was negatively associated with the silking date, indicating that earliness would be favorable for escaping from the borer’s attack. It could be concluded that the inheritance of PSB and PLB resistance can be governed by the additive gene effects, and the IL1×IL6, IL3×IL6, and IL3×IL7 hybrid combinations can be recommended as excellent combiners for resistance to PSB and PLB and good yield.

Objectives: The activity and productivity of the honey bee colony depend upon many factors operating simultaneously and reacts to some environmental conditions. We aimed to study the morphometric characteristics and glands development of nurse and forager of hybrid Carniolan honey bee (Apis mellifera carnica Pollmann) workers in relation to activities of the colony during the different seasons. Methods: The study was conducted during spring, summer, fall, then winter in 2020/2021. Ten colonies of hybrid Carniolan honey bees, every colony with about 14,000 bees, were utilizedz. The seasonal variations of foraging activity, hoarded pollen area, and sealed brood area were determined. Also, the body weight, some morphometric characteristics, and development of glands of nurses and foragers bees were measured. Results and conclusions: The highest numbers of foragers and pollen foragers/colony/min., stored pollen area, and worker sealed brood area were recorded in May. Measurements of nurses reared during spring were larger than nurses and foragers of other seasons for body weight, mandibular and hypopharyngeal glands (HPGs), length and width of the 2nd wax mirror. The highest proboscis and corbicula lengths were found in foragers reared during spring, without significant differences between worker castes. It can be concluded that the performance of the colony, morphometric characteristics, and development of glands were dependent on the time of the year. Beekeepers in Kafrelsheikh province and similar environmental condition areas should provide the colonies with pollen substitutes or supplements during April, June, and October to February to maintain the strength of the colonies.

The cotton leafworm, Spodoptera littoralis (Bosid.), is a major pest in African and Asian nations that attacks a wide variety of host plants. This study was conducted to assess the effectiveness of effective microorganisms (EMs) on the biological and physiological features of S. littoralis larvae. Five concentrations (100, 200, 300, 400, and 500 ppm) of EMs were tested. Antifeedant activity, food consumption index, the efficiency of converting digested food, the efficiency of converting ingested food, relative growth rate, and approximate body tissue of the fourth larval instar of S. littoralis were determined. Moreover, carbohydrate enzyme activities (amylase, trehalose, and invertase), total protein, and total lipids of S. littoralis larvae were measured to elucidate the mode of action of the tested agent in the S. littoralis’s larval stage. The EMs at 500 ppm had a substantial impact on antifeedant activity, nutritional indices, egg deposit reduction, and hatchability in S. littoralis during the five days. All concentrations interrupted S. littoralis’s life cycle and developmental phases. Furthermore, all concentrations were quite useful in lengthening the developmental stages of S. littoralis. In addition, Ems affected the biochemical activities of larvae, leading to disturbances in carbohydrate, lipid, and protein levels. From this study, EMs can be used as a bioinsecticide alternative to traditional insecticides against S. littoralis and may be compatible with integrated pest management approaches.

Objectives: The honeybee mainly uses the wax comb for brood rearing and food storage. Repeated brood rearing in the comb changes the wax color and cell dimensions. Therefore, we aimed to study the decline of body size of the individual bees and its impact on colony productivity in relation to comb age. Methods: Twenty colonies of hybrid Carniolan honeybees, each of 12,000 bees, were used. Combs aged 1–3 years were used as new combs, and combs aged 4–6 years as old combs. The weight of the worker, queen, drone, and royal jelly (RJ)/queen cell, storing pollen and honey, and rearing worker and drone brood were determined. Results and conclusions: The body weights of the newly emerged worker, drones, queens, and nurse and forager workers of colonies with the new combs were significantly heavier than those of the colonies with the old combs. Colonies with the new combs were significantly more active in storing pollen and honey, RJ production, and rearing workers and drones. We concluded that the body sizes of the individual bees were declined, and the productivity was decreased in the colonies with the old combs. Replace combs after three years with new others is recommended to encourage colony growth and increase productivity.

The rice weevil, Sitophilus oryzae (L.), is the most destructive insect pest of stored cereals worldwide. The current study was conducted to determine the lethal, reproductive, and histological effects of gamma irradiation on S. oryzae adults. In addition, the impact on germination, chlorophyll, and proline content in wheat seedlings from treated grains was determined. Wheat grains were infested with rice weevil adults and then irradiated by gamma rays. Gamma radiation was applied at a dosage of 0.10, 0.25, 0.50, and 1.00 kGy. Mortality percentage and LD50 were recorded after 48, 72, 96, and 120 h of treatment. The dosage of 1.00 kGy caused 100% mortality after 96 h of irradiation. The required dosage of gamma radiation to kill 50% (LD50) of adults after 48 h was 1.51 kGy. All tested doses caused complete sterility to 24 h old adults. A histological alteration was noticed at a dosage of 1.00 kGy, which showed cytoplasmic vacuolization, tissues exhibiting signs of putrefaction, and necrosis of cells; furthermore, gamma irradiation affected chlorophyll a and b. The highest amounts were detected in wheat seedlings from grains irradiated at 0.10 kGy. There was a significant increase in plant proline content at the higher doses (0.50 and 1.00 kGy) compared with seedlings from nonirradiated grains. It could be concluded that gamma radiation can be used as an eco-friendly trend to control stored-product pests without any residual effects.

Objectives: The small hive beetles (SHBs) cause dangerous damages to bee colonies in several countries. Some African countries represent the native land to these beetles. The SHBs are not well established in North Africa and South Europe (the closest land to the native countries). Therefore, this study aimed to model the current and future distribution of SHBs in Africa and South Europe utilizing temperature datasets. Methods: A total of 250 occurrence data was incorporated in the study. Six temperature variables were used in the Maxent analysis to model the suitability of the study countries for the SHBs. Three climate models were used to estimate the future distribution of SHBs in 2050 and 2070, considering the lowest and the highest limits of the Shared Socio-economic Pathways (126 and 585). Results and conclusions: The high performance of the used model was confirmed by analyzing omission/commission rates as well as the area under curve. All future maps showed the potential expansion of SHBs towards the Northern parts of Africa and some parts in Europe. Such potential expansion was discussed in light of current distribution of SHBs. The study concluded that the SHBs can cause damages to bee colonies in new regions in Africa and Europe during the near future.

Royal jelly (RJ) is commercially harvested after the 4th day of queen larval age. In the current study, it was harvested after 24, 48, 72, and 96 hours after grafting of 1-day larval age queens to investigate changes in macro and trace elements associated with harvesting time. The RJ yields were significantly affected by harvest time, and the highest yield was obtained 72 hours after grafting. The highest phosphorus (P) and zinc (Zn) contents were obtained from RJ harvested 24 hours after grafting. Royal jelly harvested 48 hours after grafting had the highest concentrations of magnesium (Mg), calcium (Ca), potassium (K), sodium (Na), iron (Fe), and manganese (Mn). Likewise, RJ harvested 96 hours after grafting had higher concentrations of copper (Cu). Royal jelly harvested 72 hours after grafting showed the second rank for P, Mg, Ca, K, Na, Fe, Cu, and Mn concentrations. In descending order, P, Mg, Ca, and K were the most dominant elements in RJ harvested at different times after grafting. The Mg, Ca, K, Na, Cu, and Mn concentrations in RJ were all positively correlated, and P, Fe, and Zn were positively correlated. The P and Zn were negatively correlated with Ca, Cu, and Mn. It was concluded that macro and trace element contents in RJ can differ depending on the harvest time after grafting. We recommend harvesting RJ at 72 hours after grafting for possible use as healthy nutritional human food supplement.

This study was conducted to compare the repellent effect and contact toxicity of eight essential oils (EOs), including Syzygium aromaticum, Allium sativum, Eucalyptus camaldulensis, Lavandula officinalis, Simmondsia chinensis, Matricaria chamomilla, Citrus limon, and Prunus dulcis, against adults of Tribolium castaneum Herbst. Four concentrations (1, 5, 10, and 15% in acetone solvent) of each EO were tested. The 5, 10, and 15% concentrations of S. aromaticum EO had a high repellency effect against T. castaneum compared with A. sativum, E. camaldulensis, L. officinalis, S. chinensis, M. chamomilla, C. limon, and P. dulcis after 30 min of exposure. The repellency test of the S. aromaticum, E. camaldulensis, L. officinalis, M. chamomilla, C. limon, and P. dulcis EOs on T. castaneum has shown that the mortality percentages enhanced with the increase in the EOs concentration and also with the exposure time. The 15% concentration of P. dulcis and M. chamomilla EOs have a significant impact on the mortality rate of T. castaneum compared with S. aromaticum, A. sativum, E. camaldulensis, L. officinalis, and S. chinensis after the 24 h of contact test. Moreover, the 15% concentration of the C. limon EO caused a greater mortality percentage compared with S. aromaticum, A. sativum, E. camaldulensis, and L. officinalis. It could be concluded that using the S. aromaticum EO as a repellent oil and using P. dulcis, M. chamomilla, and C. limon for contact toxicity to treat the flour infested by T. castaneum can play an important role in protecting stored grains and their products.

Seasonal variations in the fatty acid (FA) compositions of pollen loads collected from the Al-Ahsa Oasis in eastern Saudi Arabia throughout one year were determined to identify the optimal season for harvesting bee pollen rich in essential fatty acids (EFAs) and unsaturated fatty acids (UFAs). The highest values (%) of lipids, linolenic acid (C18:3), stearic acid (C18:0), linoleic acid (C18:2), arachidic acid (C20:0), the sum of the C18:0, C18:1, C18:2, and C18:3 concentrations, and EFAs were obtained from bee pollen harvested during autumn. The maximum values (%) of oleic acid (C18:1), palmitic acid (C16:0), UFAs, and the UFA/saturated fatty acid (SFA) ratio were found in bee pollen harvested during summer. The highest concentrations (%) of behenic acid (C22:0), lignoceric acid (C24:0), and SFAs were found in bee pollen harvested during winter. Bee pollen harvested during spring ranked second in its oleic, palmitic, linolenic, stearic, arachidic, behenic, and lignoceric acid concentrations and for EFAs, UFAs, and the UFA/SFA ratio. The lowest SFA concentration was found in bee pollen harvested during summer. Oleic, palmitic, and linolenic acids were the most predominant FAs found in bee pollen. It was concluded that the FA composition of bee pollen varied among the harvest seasons due to the influence of the dominant botanical origins. We recommend harvesting pollen loads during spring and summer to feed honeybee colonies during periods of scarcity and for use as a healthy, nutritious food for humans.

The Yemeni honeybee (Apis mellifera jemenitica Ruttner) is the native race in Saudi Arabia. The Carniolan honeybee (A. m. carnica Pollmann) and its hybrid with the Egyptian honeybee (A. m. lamarkii Cockerell) have been imported and frequently reared in Saudi Arabia. Temperature often exceed 40 °C during the summer season in most regions of Saudi Arabia. Honeybees decrease foraging activity in this period during mid-day, which affect colony productivity. The Yemeni bee race appears well adapted to these unique climatic conditions. We compared body weight and morphometric parameters of both subspecies' worker bees reared at the apiary of Training and Research Station, King Faisal University, Al-Ahsa oasis of eastern Saudi Arabia. Measurements of Yemeni bee were smaller than Carniolan bee for body weight, head structures, including antenna, flagellum, and proboscis length, thorax appendages, including femur length, tibia length and width, metatarsus length and width of the right hind leg, and length and width of the right forewing and hind wing, abdominal characteristics, including the length of the 3rd and 4th abdominal tergites and sternites, and length and width of the 1st and 4th wax mirrors. It could be concluded that with the exception of the number of hamuli, worker Yemeni bee body size and morphometric parameters related to the colony productivity were smaller than Carniolan bees under environmental conditions of the study region.

The honey bees (Apis mellifera L.) mainly use beeswax (comb) for brood rearing and food storage. Changes in the color and cell dimensions occur due to repeated food storage and brood rearing in the comb. The study aimed to determine the changes in comb cell measurements and worker body sizes in relation to comb age. For this purpose, the cell measurements of combs at age zero (wax foundation), 1, 2, 3, 4, 5, and 6 years and the body size of workers reared in them were estimated. The weight of the comb, the height of the cell base, and the weight of accumulated substances in the cell significantly increased with time. Comb age had negative effects on the cell diameter, cell depth, cell volume, cell honey or pollen capacity, and newly emerged worker body weight. Significant negative correlations were observed between the accumulated substances in a cell and the cell diameter, cell depth, and cell size, while significant positive correlations were observed among the cell volume, cell diameter, cell depth, cell honey capacity, cell pollen capacity, and worker body weight. It can be concluded that the dimensions of the comb cells and worker body size changed with the age of the comb. The obtained results recommend beekeepers to replace combs aged more than 3 years with a new comb to allow large workers to gather more nectar and pollen, rear a larger brood, and store more honey.

Royal jelly (RJ) is commercially harvested after the 4th day of queen larval age. In the current study, it was harvested after 24, 48, 72, and 96 hours after grafting of 1-day larval age queens to investigate changes in macro and trace elements associated with harvesting time. The RJ yields were significantly affected by harvest time, and the highest yield was obtained 72 hours after grafting. The highest phosphorus (P) and zinc (Zn) contents were obtained from RJ harvested 24 hours after grafting. Royal jelly harvested 48 hours after grafting had the highest concentrations of magnesium (Mg), calcium (Ca), potassium (K), sodium (Na), iron (Fe), and manganese (Mn). Likewise, RJ harvested 96 hours after grafting had higher concentrations of copper (Cu). Royal jelly harvested 72 hours after grafting showed the second rank for P, Mg, Ca, K, Na, Fe, Cu, and Mn concentrations. In descending order, P, Mg, Ca, and K were the most dominant elements in RJ harvested at different times after grafting. The Mg, Ca, K, Na, Cu, and Mn concentrations in RJ were all positively correlated, and P, Fe, and Zn were positively correlated. The P and Zn were negatively correlated with Ca, Cu, and Mn. It was concluded that macro and trace element contents in RJ can differ depending on the harvest time after grafting. We recommend harvesting RJ at 72 hours after grafting for possible use as healthy nutritional human food supplement.