Using Ferula assafoetida essential oil as adult carob moth repellent in Qom pomegranate orchards (Iran)

Carob moth, Ectomyelois ceratoniae (Lep.: Pyralidae), is the key pest of pomegranate fruits in most countries like Iran. Chemical insecticides cannot be used for the control of carob moth because they have biological and behavioral traits. Other control methods have no sufficient efficiency. So it is necessary to use new methods. Some pest control management such as application of semiochemicals like repellents are common practices. Ferula assafoetida essential oil is a botanical material and itsrepellency on some pests is proved under laboratory conditions. In this research, its repellency was studied on adult carob moth, in Qom pomegranate orchards, during a two farming seasons study (2007- 2008). Two orchards (treatment and control) were selected in about 3 km distances from each other. In treatment and control plots, F. assafoetida essential oil and ethanol (solvent) were used, respectively. During the farming season, number of rotten pomegranates of treatment and control trees were counted and removed weekly. The percentage of rotten pomegranates on trees was calculated at the end of the season. Two sample t-test showed significant differences between weekly (T = 2.22, df = 38, P = 0.032), (T = 3.11, df = 58, P = 0.003) and end of the season (T = 2.97, df = 16, P = 0.012), (T = 3.54, df = 48, P = 0.001) data of treatment and control orchards in 2007 and 2008, respectively. Number of rotten pomegranates of treatments was lower than control. Comparison of treatment and control orchards data showed damage lessening in treatment plot. Laboratory results proved repellency effect of F.assafoetida essential oil on adult carob moth in orchard conditions.Key words: Carob moth, semiochemicals, Ferula assafoetida essential oil, repellency, Iran

EFFECT OF DIFFERENT LIGHT SPECTRA ON FECUNDITY OF EPHESTIA KUEHNIELLA ZELLER (LEPIDOPTERA: PYRALIDAE)

This paper examines the effects of different light spectra on the number of eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) as a general host of biological control agents. Six distinct spectra of light, ranging from 395 nm to 625 nm, were examined in laboratory conditions. Green and red spectra with ranges of 520-525 nm and 620-625 nm caused the highest and the lowest numbers of eggs, respectively. Additionally, the effects of time on the mean egg load of E. kuehniella were also found to be significant at five days. The implications of the current results are discussed below and suggest that the application of a green spectrum in insectariums could help in increasing egg production

Étude comportementale et écologie chimique de la recherche d'un partenaire sexuel chez le puceron de la pomme de terre, Macrosiphum euphorbiae (Thomas) (Homoptera : Aphididae)

Afin d’utiliser les phéromones sexuelles dans les programmes de lutte intégrée des espèces nuisibles d’insectes, il est essentiel d’identifier les composés chimiques phéromonaux et de comprendre adéquatement la biologie reproductive des espèces considérées. Cette thèse porte sur l’étude de ces deux thèmes chez le puceron de la pomme de terre, Macrosiphum euphorbiae (Homoptera: Aphididae), un insecte nuisible pour l’agriculture à l’échelle mondiale. Les femelles sexuées vierges du puceron de la pomme de terre émettent leur phéromone sexuelle afin d’attirer les mâles conspécifiques. Lorsque soumisent à des températures froides, elles expriment ce comportement à un plus jeune âge que dans des conditions plus chaudes. En laboratoire, pour tous les régimes thermiques, une grande différence était observée au niveau du comportement d’appel en fonction de l’âge (i.e., les vieilles femelles appelaient plus tôt après l’ouverture des lumières et passaient plus de temps à appeler). Toutefois, sur le terrain, compte tenu des effets des faibles températures, des vents élevés et de la pluie sur l’activité des femelles en appel, les changements liés à l’âge étaient beaucoup moins prononcés. La phéromone sexuelle libérée par les femelles de M. euphorbiae a été identifiée comme étant un mélange de deux monoterpenoïdes, le nepetalactol (I) et la nepetalactone (II). Ces deux composés étaient présents dans un rapport de 4:1 à l’émergence des femelles. Ce ratio a changé avec l’âge, les femelles les plus âgées libérant un mélange au rapport de 2:1. Des proportions semblables de mâles de M. euphorbiae ont répondu aux mélanges synthétiques des rapports de 3:1, 4:1 et 5:1 et aux femelles vierges en appel. Cependant, les mâles mettaient plus de temps pour atteindre une source de phéromone synthétique que des femelles en appel. Le comportement des mâles face aux femelles sexuées en appel a été étudié dans des bioessais en laboratoire et sur le terrain. En laboratoire, les mâles détectaient la phéromone et s’orientaient vers la source mais ne volaient pas contre le vent lorsqu'ils étaient exposés à une source de phéromone. Par contre, ils rejoignaient la source si un pont était présent entre la source de phéromone et les cages de relâche pour leur permettre de marcher contre le vent. Sur le terrain, les comportements d'appel des femelles et de marche des mâles ont été étudiés pour différentes vitesses de vent inférieures à 5 m/s. Les femelles appelent jusqu’à une vitesse de 4 m/s mais le comportement de vol des mâles était inhibé à des vélocités supérieures à 2 m/s. Tel qu’observé en laboratoire, les mâles marchaient vers la source à des vitesses de vent élevées. Toutefois, contrairement aux résultats de laboratoire où les mâles atteignaient tous la source en marchant, 30% des mâles volaient contre le vent et se posaient sur la source. L'étude détaillée des patrons de vent a démontré qu'en présence de vent, les mâles marchaient vers la source, mais s'envolaient et progressaient vers l'avant lorsqu'une accalmie temporaire du vent se présentait.In order to use insect sex pheromones in integrated management programme of pest species, it is essential to have the correct identification of the chemical composition of pheromones and a solid understanding of the reproductive biology for the species in question. In this thesis, I examined the two aspects in the potato aphid, Macrosiphum euphorbiae (Homoptera: Aphididae), an agricultural pest of importance worldwide. Virgin female oviparae of the potato aphid release sex pheromone to attract conspecific males. At cooler temperatures females express this behavior at a younger age that at warmer ones. Under all constant temperature regimes in the laboratory there was a significant change in calling behavior as a function of age, with older females calling sooner after the “lights on” signal and spending more time calling. However, under field conditions the age related changes were much less evident due to the effects of low temperatures, high winds and rain on female calling activity. The sex pheromone emitted by calling females of M. euphorbiae was identified as a mixture of two monoterpenoids nepetalactol (I) and nepetalactone (II). The two components were present in a 4:1 ratio in the young females, but this changed with age and older females released a 2:1 ratio. A similar proportion of M. euphorbiae males responded to 3:1, 4:1, and 5:1 synthetic blends and to calling virgin, although the time taken to reach the source was less when conspecific females were used. Males’ behaviour to the calling females was examined in the laboratory and field bioassays. In the laboratory, males detected and oriented themselves to the source but did not fly upwind when exposed to calling females or appropriate lures, and only reached the source if there was a bridge available between the release cage and pheromone source allowing them to walk upwind. Under field conditions female calling, and male walking behavior were observed under variable wind speeds < 5m/s, but male flight behavior was inhibited at variable winds > 2m/s. In contrast to laboratory results where males only reached the source by walking, nearly 40% of males reaching the source did so by flying. A detailed examination of the wind patterns showed that in the presence of wind males walked towards the source but would take flight and make forward progress when there was a temporary lull in the wind

Seasonal pattern of infestation by the carob moth Ectomyelois ceratoniae in pomegranate cultivars

Pomegranate (Punica granatum L.) orchards in the Middle East are typically composed of a mix of different cultivars in which variation in fruit infestation by carob moth Ectomyelois ceratoniae (Zeller) (Lepidoptera: Pyralidae) has been observed. However, seasonal variation in infestation and adaptation of the carob moth to this cropping system have not been explored. We monitored the progress of fruit infestation in 10 pomegranate cultivars during the growing season of two consecutive years in pomegranate orchards of Iran. Overall, levels of infestation in fruits were strongly correlated with susceptibility to fruit cracking in pomegranate, so that cracked fruits and cracking-susceptible cultivars were infested the most. However, this pattern changed during the season. Infestation was first observed on cracking-susceptible cultivars. At this point almost all cracked fruits were infested. Towards the end of the season, infestation in uncracked fruits and cracking-resistant cultivars increased. Uncracked fruits seem better overwintering sites for carob moth as under simulated winter conditions, survival of insect larvae in uncracked fruits was >3 times higher than in cracked fruits. Taken together, our data reveal that cracked fruits of pomegranate are the better host during the growing season, while uncracked fruits better sustain carob moth population in winter. It seems therefore advisable not to grow cracking-susceptible and cracking-resistant cultivars together in the same area

Effect of single and mixed diets on the fitness of omnivorous thrips, Thrips tabaci (Thys.: Thripidae)

Food choice in omnivorous animals is influenced by the balance of nutritional needs, food availability, and quality of a particular food items. Here, we study whether omnivorous onion thrips, Thrips tabaci Lindeman, feed on the eggs of its competitor Tetranychus urticae Koch (Acari: Tetranychidae) when an alternative supplemental source is, or is not, available. Thrips were either fed a cucumber leaf alone, or this diet was supplemented with pollen, mite eggs, or both. We demonstrated that the supplemental food sources improved several fitness-determining traits of thrips with pollen, being nutritionally superior to mite eggs. Pollen reduced the development time and increased the population growth of thrips compared to mite eggs. When both pollen and mite eggs were available, thrips fed on both; pollen to improve nutritional status and eggs to eliminate the opponent, despite the latterâs consisting lower of nutritional benefit. In all, this study showed that omnivorous thrips benefit from a cucumber leaf diet that is supplemented with other food sources and that pollen and mite eggs increase several fitness traits and positively affect the dynamics of future thrips generations

Aversive learning in Bombus terrestris Audax (Hymenoptera: Apidae): responses to electric shock in a simulated environment

The study of animal behavior, particularly in insects, is crucial for understanding their biological and evolutionary aspects, with wide-ranging applications in agricultural science, pest management, conservation biology, and neuroscience. Investigating cognitive characteristics, specifically aversive learning, plays a pivotal role in comprehending the success of insects. This adaptive ability enables animals to efficiently cope with the stressful factors in their environment. In this study, we investigated the aversive learning capabilities of Bombus terrestris Audax workers, crucial pollinators across diverse ecosystems. Bees were trained and tested in a flight arena using artificial flowers equipped with electric shocks to simulate conditions wherebees could associate punishment alongside food resources with available cues. The result suggested that bees possess the ability to simultaneously detect potential threats and food resources, indicating a dual aversive-appetitive memory. Furthermore, comparing groups trained with aversive (electric shock) and neutral (distilled water) stimuli showed that danger cues led to faster learning and stronger memory formation. This conditioning setup aimed to simulate real-life foraging situations, exploring bee responses when confronted with potential dangers. These findings provide insights into the survival strategies of insects in challenging environments that negatively impact bee populations

Report of two fly parasitoids of carob moth, Ectomyelois ceratoniae (Lepidoptera: Pyralidae)

A study on larval parasitoids of carob moth, Ectomyelois ceratoniae Zeller, in pomegranate orchards in Ghale-Cham, Qom province and Tarom-e-sofla, Zanjan province was carried out in 2006-2007. Two species of fly parasitoids belonging to the family Tachinidae were collected and identified as Fischeria bicolor Robineau-Desvoidy and Clausicella suturata Rondani. The latter species is newly recorded from Iran

Effect of Harvesting Time on Essential Oil Content and Composition of Thymbra spicata

This study aims to investigate the essential oils content of Thymbr Spicata L. in two times before flowering and full flowering in shirpenah area in Ilam Province. Both samples were dried out in shade and without humidity. Then 50 grams of each sample were powdered after obtaining the essential oils by hydro distillation using a Clevenger apparatus for 2 hours. Resulted oils were dried by anhydrous sodium sulfate and kept in tightly closed vials at 4 °C before chemical analyses. Finally both essential oil samples were analyzed by GC and GC/MS. Outcomes show that essential oils content in full flowering was (%4.04) more than before flowering (%3.64). The compositions of essential oils in before flowering were 7 compounds and major constituents were γ-terpinene (15.5%) and carvacrol (79.3%). The composition of essential oils in full flowering were 11 and the major composition also were carvacrol (70.5%) and γ-terpinene (14.9%). α-pinene, β-pinene, α-phellandrene and cis-sabinene hydrate were not found in compositions of before flowering. It is figured that flowering time is the best for obtaining the higher essential oils content and composition in T. spicata

Effect of single and mixed diets on the fitness of omnivorous thrips, Thrips tabaci (Thys.: Thripidae)

Abstract Food choice in omnivorous animals is influenced by the balance of nutritional needs, food availability, and quality of a particular food items. Here, we study whether omnivorous onion thrips, Thrips tabaci Lindeman, feed on the eggs of its competitor Tetranychus urticae Koch (Acari: Tetranychidae) when an alternative supplemental source is, or is not, available. Thrips were either fed a cucumber leaf alone, or this diet was supplemented with pollen, mite eggs, or both. We demonstrated that the supplemental food sources improved several fitness-determining traits of thrips with pollen, being nutritionally superior to mite eggs. Pollen reduced the development time and increased the population growth of thrips compared to mite eggs. When both pollen and mite eggs were available, thrips fed on both; pollen to improve nutritional status and eggs to eliminate the opponent, despite the latter's consisting lower of nutritional benefit. In all, this study showed that omnivorous thrips benefit from a cucumber leaf diet that is supplemented with other food sources and that pollen and mite eggs increase several fitness traitsand positively affect the dynamics of future thrips generations