Evaluation of non-linear models to describe development and fertility of codling moth at constant temperatures

Μελετήθηκε η ανάπτυξη των ατελών σταδίων και η γονιμότητα των θηλέων της καρπόκαψας της μηλιάς Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) σε σταθερές θερμοκρασίες. Για την καλύτερη περιγραφή των δύο αυτών βιολογικών παραμέτρων ακολούθησε αξιολόγηση μη γραμμικών μαθηματικών υποδειγμάτων η οποία, εκτός από τον συντελεστή προσδιορισμού (R2) και το άθροισμα τετραγώνων του υπολοίπου (RSS), βασίστηκε επιπλέον και στον προσαρμοσμένο συντελεστή προσδιορισμού (R2adj) και στο πληροφοριακό κριτήριο του Akaike (Akaike information criterion - AIC). Δοκιμάστηκαν οι εξισώσεις των Enkegaard, Αναλυτή, Bieri 1 και Bieri 2, οι οποίες έδειξαν καλή προσαρμογή στα δεδομένα, ιδιαίτερα της ανάπτυξης των ατελών σταδίων [R2, R2adj, RSS και AIC κυμάνθηκαν από 0,9673-0,9917, 0,8601-0,9861, 0,08-6,7x10-4 και (-75,29) – (-46,26) αντίστοιχα]. Η ιδανική θερμοκρασία ανάπτυξης (Topt) και το ανώτερο θερμοκρασιακό όριο (Tmax) υπολογίστηκαν ικανοποιητικά από όλα τα πρότυπα (Topt: 29,9-31,2oC και Tmax: 35,9-36,7oC). Το κατώτερο θερμοκρασιακό όριο (Tmin) υπολογίστηκε ικανοποιητικά από την εξίσωση Bieri-1 (9,9-10,8oC) ενώ υποεκτιμήθηκε από την εξίσωση Αναλυτή (7,0-8,4oC). Στα δεδομένα της γονιμότητας υπήρξε καλύτερη προσαρμογή στους 30oC, (δηλαδή κοντά στην ιδανική θερμοκρασία) [R2 ,R2adj, RSS και AIC κυμάνθηκαν από 0,6966-0,7744, 0,5756-0,6455, 2,44-3,33 x10-4 και (-9,15)-7,15 αντίστοιχα].Developmental rate of immature stages and age-specific fertility of females of codling moth at constant temperatures was modeled using non-linear models. The equations of Enkegaard, Analytis, and Bieri 1 and 2 were evaluated based on the value of adjusted R2 (R2adj) and Akaike information criterion (AIC) besides coefficient of determination (R2) and residual sum of squares (RSS). All models have goodness of fit to data especially for development [R2, R2adj, RSS and AIC ranged 0.9673-0.9917, 0.8601-0.9861, 0.08-6.7x10-4 and (-75.29) – (-46.26) respectively]. Optimum temperature (Topt) and upper threshold (Tmax) were calculated accurately (Topt and Tmax ranged 29.9-31.2oC and 35.9-36.7oC) by all models. Lower temperature threshold (Tmin) was calculated accurately by Bieri-1 model (9,9-10,8oC) whereas Analytis model (7,0-8,4oC) underestimated it. As far as fertility is concerned the respective values were better fitted near the optimum temperature (in 30oC) [R2 ,R2adj, RSS and AIC ranged 0,6966-0,7744, 0,5756-0,6455, 2,44-3,33 x10-4 and (-9,15)-7,15 respectively]

Fist report of parasitoid wasps, Ascogaster quadridentata and Bassus rufipes (Hym.: Braconidae) on codling moth (Lep.: Tortricidae) larvae from Iran

در جریان بررسی دینامیسم جمعیت کرم سیب در منطقه‌ی مراغه واقع در استان آذربایجان شرقی، نمونه‌هایی از لاروهای کامل پارازیته‌شده‌ی کرم سیب از کارتن‌های بسته‌شده روی تنه‌ی درختان سیب در سال‌های 86-1385 به دست آمد. از این لاروها، 3 گونه زنبور پارازیتوئید جمع‌آوری و شناسایی شد که دو گونه‌ی Ascogaster quadridentata Wesmael و Bassus rufipes (Nees) از خانواده‌ی Braconidae برای اولین بار از ایران گزارش می‌شوند. گونه‌ی سوم،Pristomerus vulnerator (Panzer) متعلق به خانواده‌ی Ichneumonidae بوده و قبلاً از ایران گزارش شده است. بیشترین درصد پارازیتیسم در منطقه‌ی مورد مطالعه مربوط به گونه‌ی A. quadridentata بود

Tetranychid mites and their natural enemies in Maragheh region and the first record of Neopronematus neglectus (Acari: Iolinidae) from Iran

During 2006 a survey was carried out on tetranychid mites and their natural enemies in Maragheh apple orchards (North-west of Iran). In this survey a total of 20 species within the families Tetranychidae, Phytoseiidae, Stigmaeidae, Anystidae, Iolinidae, Coccinellidae, Chrysopidae and Thripidae were collected and identified. One species of the Iolinidae identified as Neopronematus neglectus (Kuznetzov) and its identity was confirmed by Dr. Edward Ueckermann from Plant Protection Research Institute of South Africa. It is reported here as a new record to Acari fauna of Iran

Life history and population growth parameters of Tyrophagus putrescentiae (Acari: Acaridae) on Fusarium graminearum in laboratory conditions

The life history of an acarid mite, Tyrophagus putrescentiae (Schrank), on Fusarium graminearum Clade was investigated at 25 ± 1°C, 60 ± 5% RH and a photoperiod of 16: 8 (L: D) h. Incubation period for egg hatch, larval and nymphal periods and adult longevity were 2.22 ± 0.06, 3.46 ± 0.12, 4.84 ± 0.16 and 10.05 ± 0.9 days, respectively. The average life span of males and females were 22.22 ± 1.21 and 19.08 ± 1.37 days respectively. Pre-oviposition, oviposition and post-oviposition periods were 2.22, 5.77 and 1.4 days respectively. Gross and net fecundity rates were obtained 76.2 and 23 eggs per female per generation respectively. Net reproduction rate was 12.5 female eggs per female per generation, and average daily oviposition rate was 5.7 eggs. The intrinsic and finite rates of population increase were 0.15 and 1.16 day-1 respectively. The mean generation time (T) and the mean doubling time (DT) were 16.74 and 4.59 days respectively. The population mainly (78%) consisted of eggs and larvae, and nymphs and adults represented only 22% of the population

Population fluctuation of Neoseiulus barkeri (Acari: Phytoseiidae) and its prey, Tetranychus urticae (Acari: Tetranychidae), in cucumber fields of Khorramabad, Iran

Population density and spatial distribution of Neoseiulus barkeri Hughes and its prey, Tetranychus urticae Koch, in cucumber fields of Sarab-e Chengaei region in west of the city of Khorramabad, Lorestan province, were studied in 2008-2009. The population densities of both species in the first year was higher than the second year. The population densities for T. urticae and N. barkeri reached their peaks in late July and late August 2008, respectively. In 2009, the population peaks for both species occurred in late August. The reaction of N. barkeri to different population densities of its prey, with linear regression, was described as density independent. It was also found that mated females of N. barkeri overwintered in soil. The Taylor's power law regression method was used for finding the spatial pattern of the predator and prey, which was aggregated for both species. The correlation between the population fluctuation and spatial distribution pattern of the pest and its predator can effectively help to improve the strategy for a successful IPM program

Population growth parameters of Tetranychus urticae (Acari: Tetranychidae) on different bean varieties

Population growth parameters of Tetranychus urticae Koch on four bean varieties including Talash (Colorado bean), Sadaf (Navy bean), Goli (Kidney bean) and Parastoo (Black-eye bean) were investigated in laboratory conditions at 25 ± 1°C, 60 ± 5% RH and a photoperiod of 16: 8 (L: D) h. In this experiment, one-day old eggs of T. urticae were selected and reared in growth chamber until the death of the last female mite, and the survival rate and female progeny of the mite were measured. Net reproduction rate (R0) on four bean varieties, was 8.822, 3.622, 4.908 and 2.043, intrinsic rate of increase (rm) was 0.142, 0.079, 0.095 and 0.038, and finite rate of increase (λ) was 1.152, 1.082, 1.099 and 1.039, respectively. Mean generation time (T) was determined 15.381, 16.283, 16.715 and 18.308 and doubling time (DT) was 4.901, 8.787, 7.292 and 18.125 days, respectively. The results indicated that the rate of population growth of T. urticae on Talash variety was more than other varieties. The rates of population parameters on Parastoo variety were the least

First record of Agistemus collyerae (Acari: Stigmaeidae) from Iran

During a survey on stigmaeid mites in northwestern Iran (2004-2006), several specimens of the family Stigmaeidae were collected on olive trees in Moghan (Ardebil province) in July 2006. These mites were later identified as Agistemus collyerae Gonzalez-Rodriguez. This is the first record of this species from Iran. The specimens were collected along with the specimens of the family Eriophyidae on olive leaves demonstrating a type of correlation between stigmaeid and eriophyid mites. Further studies on the ecological roles of these mites will provide better understanding of their coexisting behavior

Demographic parameters of the diamondback moth, Plutella xylostella (Lep.: Plutellidae) on five rapeseed cultivars

The diamondback moth, Plutella xylostella (L.) (Lep.: Plutellidae) is one of the most destructive insectpests of cruciferous crops throughout the world. In this research, the demographic parameters of P. xylostellawere studied on five rapeseed cultivars including Licord, Modena, Okapi, RGsoo3 and REGXkobra. Theexperiments were conducted in a growth chamber at temperature of 25 ± 1°C, 60 ± 5% RH and aphotoperiod of 16: 8 (L: D) hr. The mortality of preimaginal stages differed from 47.65 to 65.75% onModena and REGXkobra, respectively. The life expectancy of newly laid eggs and one-day-old adults ofP. xylostella was estimated as 13.48, 4.90; 14.69, 10.84; 15.39, 7.72; 16.25, 12.23; 15.06 and 6.05 dayson Licord, Modena, Okapi, RGsoo3 and REGXkobra, respectively. There was significant differencebetween net reproductive rates (Ro) of the cultivars. The highest value of Ro belonged to RGsoo3 (74.97 ±7.99). The longest generation time was on Rgsoo3 while the shortest one belonged to the Modena. Theintrinsic rate of natural increase (rm) on Modena was significantly differed from other cultivarsemphasizing that Modena was the most sensitive cultivar to the diamondback moth than the others

The influence of temperature on the functional response and prey consumption of Neoseiulus barkeri (Acari: Phytoseiidae) on Tetranychus urticae (Acari: Tetranychidae)

The foraging behavior of a natural enemy is greatly affected by temperature. The influence ofdifferent constant temperatures on the functional response and prey consumption of the mated female ofNeoseiulus barkeri Hughes on nymphal stages of Tetranychus urticae Koch was evaluated. Four ambienttemperatures (20, 25, 30 and 35 ± 1°C) and six prey densities (2, 4, 8, 16, 32 and 64 individuals) wereused during a 24-h period in functional response experiments. The effect of seven constant temperatures(15, 20, 25, 27, 30, 35 and 37 ± 1°C) on prey consumption of N. barkeri on nymphal stages of T. urticaewas also determined. Using the logistic regression, the type II functional response was determined foradult female of N. barkeri at all temperatures. The type II Rogers' model was used to estimate the valuesof the searching efficiency (a) and handling time (Th). The value of the searching efficiency increasedwith increasing temperature from 20 to 30°C (0.0364 to 0.0731 h-1 respectively), then decreased at 35°C(0.0646 h-1). The handling time of this predator decreased when the temperature increased from 20 to35°C, and the minimum value was observed at 35°C (0.5548 h). Similarly, temperature had a significanteffect on the prey consumption of adult females of N. barkeri over the range of 15-37ºC. The minimumand maximum daily prey consumption of whole immature stages of N. barkeri was observed at 15°C and35°C respectively. The highest and the lowest number of total preys consumed by all immature stages ofN. barkeri were 14.61 and 8.79 preys that occurred at 20°C and 15°C respectively. During the ovipositionperiod, the total prey consumption increased with increasing temperature from 15 (160.43 preys) to 30°C(286.71 preys) and then declined and reached to 191.57 preys at 37°C. The results of this studyunderscore the effect of temperature on searching efficiency and prey consumption of N. barkeri

First report of Tydeus caudatus (Acari: Tydeidae) from Iran

در این یادداشت، کنه‌ی Tydeus caudatus (Duge`s) از باغات میوه کرمانشاه برای اولین بار از ایران گزارش می‌‌شود. همچنین، تاریخچه‌ای مختصر از تاکسونومی همراه با خصوصیات ریخت‌شناسی این کنه ارایه شده است