Nitrite is one of the harmful pollutants for both people and animals. The formation of nitrite during the manufacturing of beet sugar was investigated. The results indicated that the cossettes contained lower nitrite content (1.23±0.1 mg/kg DM). However, the nitrite mainly formed during the extraction and purification processes. Most of the nitrite was transferred to molasses, with the remaining portion returning to the crystallization process through the circulation of juices. The nitrite content of raw juice was lower than 10 mg/kg DM in the aerobic extraction system, and it was reduced by 50% during the liming and carbonation. In the tower extraction system for both factories F1 and F2, the nitrite content increased from 5.5 and 25 mg/kg DM in the raw juice to 298 and 247%, 284 and 238%, 716 and 1032%, and 307 and 881% in the thin juice, thick juice, raw sugar green, and molasses, respectively. A significant reduction in the nitrite content of raw and de-foamed juice was achieved by the suggested point (L3) for dosing the disinfectant B (hop β-acids). The effect of the disinfectant lasted for more than 6 h at normal nitrite levels of juice and up to 90 min at high nitrite levels. Furthermore, the nitrite contents were reduced in thin juice, thick juice, and molasses by 58, 48 and 30%, respectively. By optimizing the dosing procedure and point of disinfectant hop β-acids dosage, the microbial load on the extraction system and formation rate of nitrite could be reduced significantly.

Honeybees exposed to pesticides direct or indirect ways through their food
research trips. Herein, this study examined the toxicity effects on laboratory of
seven tested pesticides insecticides from different pesticide groups. emamectin
benzoate, imidacloprid, chlorpyrifos, indoxacarb, lambada cyhalothrine,
glyphosate and thiophanate-methyl on honeybee workers, Apis mellifera L.
through different exposure periods of time at 24, 48, and 72 hours. The selected
pesticides were ranked based on their toxicity from the most to least one as
following: emamectin benzoate, imidacloprid, chlorpyrifos, indoxacarb, and
lambda cyhalothrine. Further, thiophanate-methyl and glyphosate were the lowest
toxicity among selected pesticides. The highest toxic pesticide during the exposure
period 24, 48 and 72 hrs was emamectin benzoate with LC50 values (0.247, 0.047
and 0.020 ppm) and with LC90 values (5.752, 0.302 and 0.072 ppm) respectively,
and the least one was glyphosate with LC50 values of (6861.151, 3366.968 and
2477.267 ppm) and LC90 values of (28243.795, 9033.695 and 6203.485 ppm) after
24, 48 and 72hr of exposure respectively. However, chlorpyrifos ranked the third
toxic pesticide at 24 and 48 hrs of treatment with LC50 values of 10.226 and 2.731
ppm and with LC90 values of (101.224 and 7.496 ppm for 24 and 48 hrs,
respectively). Whereas, after 72 hrs chlorpyrifos recorded the fourth toxic pesticide
with LC502.086 ppm and LC90 5.179ppm. Based on the toxicity index, results
showed that, the most to least toxic pesticides were arranged as followed:
emamectin benzoate>imidacloprid >chlorpyrifos >indoxacarb >lambada
cyhalothrine> thiophanate -methyl > glyphosate. These results demonstrated that
pesticides are very toxic to honeybee workers and must avoid applying them
during the times when bees are most active such as during flowering periods.
 

Incidence of mature and immature stages of pomegranate butterfly, Deudorix livia Klug (Lepidoptera: Lycaenidae) was studied regarding to some host plants phenology during growth stages. The hosts are sweet acacia, Acacia farnesiana L., and pomegranate, Punica granatum L.. Besides, study its eggs population fluctuation on Manfaloty pomegranate cultivar during 2020 and 2021 under climatic factors [Maximum (MaxT) and Minimum (MinT) Temp. in Celsius degree (°C), Relative humidity (RH %), and Wind Speed (km/hr.)]. The sweet acacia was the most favourable for D. livia and represented the main host plant during the absence of targeted stage of other host plants. Eggs and adults were first observed after 2 and 7 weeks from fruit setting on sweet acacia; respectively in 2020 and 2021. On pomegranate the previous stages appeared after 3 weeks of fruit formation in both seasons. October was the best month for egg deposition in both seasons, because egg averages highly increased and this was the damaging time for pomegranate fruits. The populations of eggs showed three peaks in 2020 and two in 2021. The correlation coefficient between average numbers of eggs and maximum wind speed was negative and highly significant (r= -0.36776, P= <.0001) in 2020, meanwhile in 2021 still negative with non-significant effect (r= -0.10447, P= 0.1410). In conclusion, determine pest peaks is important to establish control program before peaks occurrence or after infestation reaches to economic threshold levels. This will be important to directed control strategies to prevent pest from laying eggs on pomegranate fruits.

From late autumn until the end of winter conditions, bees are exposed to many stress factors including low air temperature and several pathogens. This study aimed to estimate the effects of three commercial materials (acetylsalicylic acid, Echinacea purpurea extract, and vitamin (C) mixed with sugar feeding on some parameters related to stress tolerance using laboratory and field tests. The laboratory tests supported the potential role of vitamin C and Echinacea purpurea extract to enhance the tolerance ability of bees to low temperatures. The most promising results for the recovery time of bees after exposure to low temperatures, survival rates after narcosis, and hemocyte count were recorded with these two materials. After winter the strength of bee colonies fed on sugar feeding mixed with vitamin C and Echinacea purpurea extract were approximately equal to the strength before winter. However, the contrary was obtained with acetylsalicylic acid and the control group. Thus, using vitamin C or Echinacea purpurea extract as safe additives can boost the survival of bee colonies during the winter period.

Bee pollen is a natural cocktail of floral nectar, flower pollen, enzymes, and salivary secretions produced by honeybees. Bee pollen is one of the bee products most enriched in proteins, polysaccharides, polyphenols, lipids, minerals, and vitamins. It has a significant health and medicinal impact and provides protection against many diseases, including diabetes, cancer, infectious, and cardiovascular. Bee pollen is commonly promoted as a cost-effective functional food. In particular, bee pollen has been applied in clinical trials for allergies and prostate illnesses, with a few investigations on cancer and skin problems. However, it is involved in several patents and health recipes to combat chronic health problems. This review aimed to highlight the clinical trials and patents involving bee pollen for different cases and to present the role of bee pollen as a supplementary food and a potential product in cosmetic applications.

A honey bee colony’s ability to grow and develop is dependent on adequate nutrition. Bees collect pollen from flowers as a source of protein, fat, vitamins, and minerals. The crude protein content of corn pollen is considered low, around 15%; however, bees frequently visit the male flowers of the tassels for pollen. In this study, we aimed for the first time to improve the nutritious value of corn pollen by mechanically crushing its external pollen wall. We then compared the effect of feeding crushed vs. non-crushed corn pollen grains on honey bee diet consumption, digestibility, hemolymph protein content, hypopharyngeal gland (HPG) size, and thorax weight under laboratory conditions. We found that crushing corn pollen grains increased diet digestibility and hemolymph protein content while decreasing honey bee pollen consumption (− 39.88%). Crushing pollen however had no effect on HPG size or thorax weight. These findings may be beneficial to beekeepers in areas where corn monoculture is prevalent. The effect of crushed corn pollen on larval development and growth, as well as colony development and vitality, should be investigated in future studies.

We investigated the effect of adult honey bee pollen nutrition on the flight performance of honey bees. Therefore, caged bees were allowed to perform 30 min of defecation/training flights every second day before flight performance of pollen-fed bees and pollen-deprived bees older than 16 days were compared in a flight mill. We first fed 10 µL of 1 M glucose solution to bees, and after they metabolized this during flight, they were fed 10 µL of 2 M glucose solution for a second flight test. Pollen-deprived bees flew longer and further than pollen-fed bees in both flights. Pollen-fed bees flew faster in the early period at the beginning of flights, whereas pollen-deprived bees were faster in the final phases. Pollen-fed bees were able to raise their maximum flight speed in 2 M glucose solution flights, whereas pollen-constraint bees were not. The two groups did not differ in abdomen fresh weight, but the fresh weight of the head and thorax and dry weight of the head, thorax and abdomen were higher in pollen-fed bees. In a second experiment, we constrained pollen consumption of caged bees during the first 7 days and compared daily consumption of bees from day 8–16 to consumption of bees unrestricted in pollen. We found that pollen-deprived bees perceive the pollen shortage and try to compensate for their needs by consuming significantly more pollen at the later phase of their life than pollen-fed bees of the same age. Still, bees constrained from pollen in the first 7 days did only reach 51.1% of the lifetime consumption of unconstrained bees. This shows that bees can sense the need for essential nutrients from pollen, but their physiological apparatus does not allow them to fully compensate for their early life constraint. Pollen deprivation only in the first 7 days of worker life likewise significantly reduced fresh and dry weights of the body sections (head, thorax, and abdomen) and survival. This underlines the importance of protein consumption in a short critical period early in adult bees’ lives for their development and their performance later in life.

This article presents managed honey bee colony loss rates over winter 2019/20 resulting from using the standardised COLOSS questionnaire in 37 countries. Six countries were from outside Europe, including, for the first time in this series of articles, New Zealand. The 30,491 beekeepers outside New Zealand reported 4.5% of colonies with unsolvable queen problems, 11.1% of colonies dead after winter and 2.6% lost through natural disaster. This gave an overall colony winter loss rate of 18.1%, higher than in the previous year. The winter loss rates varied greatly between countries, from 7.4% to 36.5%. 3216 beekeepers from New Zealand managing 297,345 colonies reported 10.5% losses for their 2019 winter (six months earlier than for other, Northern Hemisphere, countries). We modelled the risk of loss as a dead/empty colony or from unresolvable queen problems, for all countries except New Zealand. Overall, larger beekeeping operations with more than 50 colonies experienced significantly lower losses (p < 0.001). Migration was also highly significant (p < 0.001), with lower loss rates for operations migrating their colonies in the previous season. A higher proportion of new queens reduced the risk of colony winter loss (p < 0.001), suggesting that more queen replacement is better. All three factors, operation size, migration and proportion of young queens, were also included in a multivariable main effects quasi-binomial GLM and all three remained highly significant (p < 0.001). Detailed results for each country and overall are given in a table, and a map shows relative risks of winter loss at the regional level.

To enhance the performance of honey bee colonies and to improve the physiological characteristics of honey bee workers in late winter and early spring (dearth period) in Assiut region, Upper Egypt—three pollen substitutes rich in protein and available in the local market were used and compared with bee bread as a control. The pollen substitutes were administrated at 7-day intervals for 15 wk, from December 2018 to March 2019. The rate of food consumption, sealed brood areas, bee population size, and characteristics of hemolymph of honey bee individuals were measured. Stored bee bread was the best protein source for developing honey bee colonies, continued with date syrup, recording the highest sealed brood areas compared with the rest of the diets. All hemolymph parameters under substitute feeding conditions were less than those determined under control conditions (bee bread), and the numbers of spring bees were more than those of winter bees. Total soluble solids (TSS), total hemolymph count (THC), differential hemolymph count (DHC), and hemolymph protein concentration (HPC) differed significantly among the experimental treatments with a significant superiority of date syrup (diet 3) over the others. It can be concluded that the date syrup was more suitable for honey bee colonies which was more favorable than traditional pollen substitute and improved physiological status of honey bee individuals during pollen scarcity periods. So under Upper Egypt conditions, pollen substitute feeding especially date syrup during the winter-early spring period under pollen scarcity helped honey bee colonies to be developed in the early spring seasons.

Several pesticides may be directly responsible for reducing the performance and losses of honeybee colonies. The action of feeding a nursing honeybee worker sugar solution with a sublethal concentration of seven pesticide groups was evaluated under laboratory conditions. Various physiological characteristics of nursing honeybees including food consumption, development of food glands, body water content, and food reserves were considered as indications for the functional status of nursing honeybee workers. Food consumption rate was significantly reduced in all treatments except two treatments, chlorpyrifos, and thiophanate-methyl. Also, the development of hypopharyngeal glands was significantly reduced in all treatments the reduction ranged between   31 to 55.62%. At the end of the nursing period, the state of metabolism as a food reservoir was determined. A maximum decrease in adult water content was recorded under the effect of lambada-cyhalothrine pesticide treatment without any significant difference in all treatments. Otherwise, the protein content of adults significantly decreased in all treatments except with lambada-cyhalothrine pesticide treatment. Fat content significantly increased in all treatments. The present data reflects the negative effects of sublethal concentration after dietary oral application of certain pesticide groups during the nursing period of the honeybee