Light intensity and wavelength influence development, reproduction and locomotor activity in the predatory flower bug Orius sauteri (Poppius) (Hemiptera: Anthocoridae)

Light wavelength and intensity are physical factors that can affect arthropod development and reproduction. The present study examined the development, reproduction and locomotor activity of the predatory flower bug, Orius sauteri (Poppius) (Hemiptera: Anthocoridae), under five light intensities (1000, 2000, 3000, 4000 and 5000 lux) and five wavelengths [red (678.5 nm), green (620.0 nm), yellow (581.7 nm), blue (478. 1 nm) and white (all wavelengths)] at constant temperature (25 °C) and RH (70 %). The duration of nymphal development was extended at lower light intensities, primarily due to effects on the first three instars. Under white, yellow and green light, O. sauteri completed development in 18.0 days, but blue light extended development by 3.2 days and red light extended it by 7.4 days. Although lower light intensities extended the preoviposition period and reduced fecundity, they improved egg fertility. Both red and blue light negatively affected preoviposition period, fecundity and egg fertility. Whereas adult female mean walking speed over a five min period was reduced at lower light intensities, longer wavelengths (yellow and red) increased it, ostensibly reflecting an avoidance response. The respiration quotient of adult O. sauteri females was also elevated under red light conditions. These findings are informative for optimizing O. sauteri mass-rearing procedures and maximizing its efficacy as a biological control agent in greenhouse cultures.     

Side-effects of pesticides on the predatory bug Orius laevigatus (Heteroptera: Anthocoridae) in the laboratory

Laboratory trials were carried out in order to test the effects of 29 pesticides on the predatory bug, Orius laevigatus. To evaluate residual contact activity, newly moulted fourth instar nymphs of O. laevigatus were placed on treated Petri dishes and their mortality was checked after 7 days. The fecundity of surviving females was tested for 14 days. Young O. laevigatus adults were fed with eggs of Ephestia kuehniella, treated with the (above-mentioned) pesticides, to assess the effect of pesticides by ingestion. Adult mortality, female fecundity and egg hatching were recorded. Azadirachtin, granulosis virus products, mineral oil, pirimicarb, tebufenozide, clofentezine, hexythiazox and copper oxychloride had no significant effect on the survival and fecundity of O. laevigatus when predators were exposed to pesticide residues by contact or by ingestion. Triflumuron and diflubenzuron appeared to be harmless by contact, but diflubenzuron was slightly toxic when ingested. Buprofezin and teflubenzuron were slightly to moderately toxic, while hexaflumuron, flufenoxuron, and lufenuron showed a marked toxicity by contact as well as by ingestion. A number of organophosphates, endosulfan and deltamethrin were detrimental especially by contact. Imidacloprid was very toxic by contact but only slightly toxic when ingested. Indoxacarb and methoxyfenozide were less toxic than imidacloprid. These findings should be considered when releases of O. laevigatus are used in greenhouses or on outdoor crops.     

二种活体饲料对东亚小花蝽生长发育和生殖的影响

本文比较了果蝇Drosophila melanogaster(Meigen)幼虫和西花蓟马Frankliniella occidentalis(Pergande)2种活体饲料对东亚小花蝽Orius sauteri(Poppius)生长发育和生殖的影响。结果显示:果蝇幼虫饲喂的东亚小花蝽幼虫发育历期12.36d,与西花蓟马饲喂的(12.19d)相近。果蝇幼虫饲喂的东亚小花蝽产卵量(89.58粒)与西花蓟马饲喂(95.72粒)相当。表明果蝇幼虫与传统活体饲料西花蓟马饲养东亚小花蝽的效果相当,可以很好的满足东亚小花蝽生长发育和生殖的要求。由于西花蓟马饲喂成本比较高,实际操作中有一定困难,果蝇幼虫是一种较为理想的活体饲料。     

Olfactory response of the anthocorid predatory bug Orius sauteri to thrips-infested eggplants

The predator Orius sauteri (Poppius) (Heteroptera: Anthocoridae) is an effective arthropod natural enemy of thrips, especially Thrips palmi Karny (Thysanoptera: Thripidae), a serious pest of vegetables. First, we studied O. sauteri's response to the odour from thrips-infested eggplant [Solamum melongena L. (Solanaceae)] in a laboratory by two-choice experiments using a Y-tube olfactometer. When detached eggplant leaves were used as odour sources, O. sauteri preferred the volatiles from uninfested leaves to clean air. Concerning preferences among differently infested leaves, O. sauteri preferred the volatiles from plants infested with 10–100 thrips per leaf to uninfested leaves, but showed no significant preference for artificially damaged leaves over uninfested leaves. Similar results were obtained when complete plants were tested as the odour source. Second, release and recapture experiments in a greenhouse, a more realistic set of conditions, were conducted to confirm whether a significant preference for infested plants occurred at similar infestation levels as in the laboratory. Trends favouring infested plants were detected at densities of five and 500 thrips per plant; however, at the five thrips per plant, this trend was due to the large deviation seen in infested plants in only one replicate. In light of the low tolerable thrips density of eggplant, it is necessary to confirm whether artificial treatments with chemicals induce the emission of herbivore-induced plant volatiles that can attract O. sauteri and prolong its residence time on the leaf.     

东亚小花蝽人工饲料微胶囊剂型的研制及饲养效果评价

通过正交试验对东亚小花蝽Orius sauteri人工饲料微胶囊进行了配方优化研究, 明确了海藻酸钠及壳聚糖的填充比例和芯壁比例在微胶囊产率、包埋率和含水率等方面的影响。各配方因素对产率的影响程度依次为: 芯壁比 > 海藻酸钠填充比 > 壳聚糖填充比; 而各因素对包埋率的影响程度依次为: 壳聚糖填充比 > 海藻酸钠填充比 > 芯壁比; 含水率受海藻酸钠填充比影响最大, 而后依次为壳聚糖填充比和芯壁比; 在海藻酸钠填充比为2.0%、壳聚糖填充比为0.6%及芯壁比为1∶3时, 所得人工饲料微胶囊感官评定得分最高。以包埋率作为基准考量下, 取最佳配比为海藻酸钠填充比为1.0%, 壳聚糖填充比为0.8%, 芯壁比为1∶1的配方, 制作人工饲料微胶囊饲喂东亚小花蝽, 与取食朱砂叶螨Tetranychus cinnabarinus组为对照, 进行了饲喂效果试验。结果表明: 与对照组相比, 取食人工饲料微胶囊后, 东亚小花蝽1、 2龄若虫发育历期显著延长, 雌成虫寿命显著缩短; 羽化率和产卵前期差异不显著, 但产卵期、产卵量和卵孵化率显著降低。此外, 取食人工饲料微胶囊的东亚小花蝽成虫呼吸墒显著低于对照, 运动速率则显著高于对照。     

Residual effects of four pesticides on the predatory bug,Orius albidipennis Reut. (Hem.: Anthocoridae)

Residual effects of abamectin (0.02%), propargite (0.1%), dichlorvos (DDVP) (0.15%) and pymetrozine (0.15%) were determined on Orius albidipennis at laboratory conditions. Planted cucumbers were sprayed with the highest recommended concentrations of all insecticides and experimental treatments were monitored during 20 days based on the period of pesticides residues. On the first day after spraying, the greatest of mortality belonged to dichlorvos and pymetrozine (97 ± 1.22, 57 ± 3.1, respectively, p < 0.01), while abamectin and propargite had the highest mortality after four (44 ± 1.87 and 24 ± 2.91, respectively, p < 0.01) and eight (51 ± 2.91 and 17 ± 2.23, respectively, p < 0.01) days after spraying. At day 16th, post treatment, abamectin had the highest residual mortalities on O. albidipennis (15 ± 1.58, p < 0.01) and finally mortality results at the 20th day showed there is no significant difference between insecticides (p < 0.01).     

Rearing of Orius strigicollis (Heteroptera: Anthocoridae) on Artificial Diet

Orius strigicollis (Poppius) was reared on the modification of rearing media for Tetrastichus sp. at 28°C, 18L: 6D, and 50‐60% RH, in which meat diets were used for partial replacements of insect source of the artificial diets. Life history traits of the predacious bug fed on the diet were measured. Nymphal development period and mortality rate of O. strigicollis were about 14 days and 31.5% (survival rate: 68.5%), respectively. The female bug produced average of 82.5 eggs during its oviposition period of 18 days when artificial oviposition substrate was provided. The fecundity was shown to be superior compared with previous researches on the species fed natural preys as a food.     

Acceptance and suitability of four plant substrates for rearing Orius sauteri (Hemiptera: Anthocoridae)

Orius sauteri (Poppius) is an important hemipterous predator that has been mass-reared for biological control of numerous pests in protected crop-production systems. To find a good oviposition substrate for mass-rearing this predator under insectary conditions [25°C, 65 ± 5% relative humidity, and a photoperiod of 16:8 (L:D) h], we compared kidney bean, soybean, broad bean sprouts and fresh leaves of kidney bean. We found that O. sauteri made more punctures and laid more eggs in kidney bean sprouts than in the other substrates examined. However, there were no significant differences among substrates in the proportion of punctures receiving eggs. Female O. sauteri laid the most eggs (as many as 68 eggs) in kidney bean sprouts and also had the shortest pre-oviposition period on this plant material. In addition, there were no significant differences in total oviposition durations or female longevity among the four plant substrates. The hatch rates of nymphs in the sprouts and leaves of kidney bean (>90%) were higher than those in soybean and broad bean sprouts. Thus, we found that the kidney bean sprout was the most suitable substrate for mass-rearing of O. sauteri.     

Optimization an Optimal Artificial Diet for the Predatory Bug Orius sauteri (Hemiptera: Anthocoridae)

Background

The flower bug Orius sauteri is an important polyphagous predator that is widely used for the biological control of mites and aphids. However, the optimal conditions for mass rearing of this insect are still unclear, thus limiting its application.

Methodology

In this study, we investigated the optimal ingredients of an artificial diet for raising O. sauteri using a microencapsulation technique. The ingredients included egg yolk (vitellus), whole-pupa homogenate of the Tussah silk moth (Antheraea paphia), honey, sucrose, rapeseed (Brassica napus) pollen and sinkaline. We tested 25 combinations of the above ingredients using an orthogonal experimental design. Using statistical analysis, we confirmed the main effect factors amongst the components, and selected five optimal combinations based on different biological and physiological characters.

Principal Findings

The results showed that, although different artificial diet formats significantly influenced the development and reproductive ability of O. sauteri, the complete development of O. sauteri to sexual maturity could only be achieved by optimizing the artificial diet according to specific biological characters. In general, pupae of A. paphia had more influence on O sauteri development than did artificial components. The results of a follow-up test of locomotory and respiratory capacity indicated that respiratory quotient, metabolic rate and average creeping speed were all influenced by different diets. Furthermore, the field evaluations of mating preference, predatory consumption and population dispersion also demonstrated the benefits that could be provided by optimal artificial diets.

Conclusions

A microencapsulated artificial diet overcame many of the difficulties highlighted by previous studies on the mass rearing of O. sauteri. Optimization of the microencapsulated artificial diet directly increased the biological and physiological characters investigated. Successive physiological tests and field investigations were used to evaluate the outcome of different artificial diet combinations on the quality of the reared O. sauteri.     

Life history parameters of Orius sauteri (Poppius) (Het., Anthocoridae) reared on Ephestia kuehniella eggs and the minimum amount of the diet for rearing individuals

Abstract: Mass rearing techniques are essential elements in developing a reliable and economic biological control method for Orius sauteri, a promising indigenous Orius species for biological control of Thrips palmi in greenhouses. Orius sauteri was reared on Ephestia kuehniella eggs and life history parameters and the minimum number of E. kuehniella eggs for rearing O. sauteri individuals were measured at 25°C and L16:D8. Developmental time during the nymphal stages was about 14 days for both sexes. Total fecundity and female longevity were 103.9 and 27.9 days, respectively. The intrinsic rate of natural increase per day was 0.115. An individual requires at least 30 eggs for nymphal development and survival and 20 eggs for adult oviposition and survival per four days.     

Development of Orius vicinus (Ribaut) (Heteroptera: Anthocoridae) on Different Prey

The survival, development and adult size of Orius vicinus were studied on five prey species, the mites Aculus schlechtendali, Panonychus ulmi and Tetranychus urticae, and larvae of the insects Dasineura mali and Thrips obscuratus. Survival was high (74-100%) and O. vicinus was able to complete development on all prey species in an average of 22-26 days at 20 C. The most rapid development occurred on T. obscuratus, T. urticae and P. ulmi. Adult size was estimated from the length of the fifth instar cast skin, which averaged 2.18 to 2.48 mm on different prey. The largest bugs were obtained from feeding on T. obscuratus or D. mali. O. vicinus, which were fed A. schlechtendali, were the slowest to develop and produced the smallest adults. The results are discussed in relation to prey availability and observed predation in the field, and are compared with previous feeding studies.     

Taxonomic review of the genus Orius (Heteroptera: Anthocoridae) in the Korean Peninsula

A total of five species the genus Orius are revised from the Korean Peninsula, containing four native species, O. minutus (Linnaeus 1758), O. sauteri (Poppius 1909), O. nagaii Yasunaga 1993 and O. strigicollis (Poppius 1914), and an introduced species for biological control, O. laevigatus Fieber 1860. Orius laticollis Reuter 1884, formally recorded in the Korean Peninsula, is deleted from the Korean fauna registry. The preparation of the macerated slide specimen was applied to this group for the first time, which is confirmed to be effective to identify the Orius species, especially the female specimens whose genital structures have been hardly observed in the traditional dissection method. Observing macerated specimens, new taxonomical characters are documented.     

Laboratory test method to evaluate the effect of 31 pesticides on the predatory bug,Orius laevigatus (Het: Anthocoridae)

A laboratory test method was developed to evaluate the pesticide toxicity on the predatory bugOrius laevigatus (Fieber). Newly hatched first-instar nymphs ofO. laevigatus were exposed to spray deposits of pesticides that were sprayed on the glass plates of a drum cell at the manufacturer’s recommended maximum dosage. Nymphal mortality and oviposition of surviving adults were recorded. Test results of various (31) commonly used pesticides (insecticides, insecticides/acaricides, acaricides and fungicides) are presented and discussed in accord with the classification of the IOBC/WPRS Working Group ”Pesticides and Beneficial Organisms”. Most fungicides had no toxic effect on nymphal development and egg-laying of surviving adults. The acaricides tested had variable toxicity on the predatory bug, while some insect growth regulators, such as the benzoylphenyl urea were very toxic. Otherwise, the ecdysone agonist tebufenozide and azadirachtin were not harmful for nymphal development and oviposition     

小花蝽属两种核型的研究(半翅目: 花蝽科)

本文利用姬姆萨染色空气干燥压片方法,对花蝽科小花蝽属中国2种小花蝽的性细胞核型进行了研究.研究结果表明该2种小花蝽的2倍体均具有24条染色体和X-Y性别机制,但2种间在染色体行为特征方面具有差别,主要表现在细胞减数分裂的晚终变期和中期常染色体以及性染色体的排列形状与位置等方面,该特征可以用于种间的细胞分类.     

The influence of intraguild competitors on reproductive decisions by two predatory Heteroptera,Orius insidiosus (Anthocoridae) and Nabis americoferus (Nabidae)

The relationship between the oviposition site preferences of predators in the face of intraguild competitors has received little attention, but it likely shapes the reproductive ecology of predatory species. In this study, oviposition intensity and the within-plant distribution of Orius insidiosus (Heteroptera: Anthocoridae) and Nabis americoferus (Heteroptera: Nabidae) eggs on Phaseolus vulgaris plants was studied when the two species were present independently or in combination. Both predators laid more eggs in the presence of the other species relative to when they were only exposed to conspecifics. When only exposed to conspecifics, O. insidiosus preferred to lay eggs on leaves and petioles on the upper half of the plant, whereas N. americoferus laid eggs mostly on the petioles and petiolules equally throughout the height of the plant. But when both species were present, O. insidiosus preferred to lay eggs on the leaf, whereas N. americoferus altered their behavior to lay an even greater proportion of their eggs on the petioles and petiolules. They altered their preferences for different plant strata too: N. americoferus laid more eggs on the upper quarter of the plant when O. insidiosus was present, and O. insidiosus was marginally more likely to lay eggs lower on the plant in the presence of N. americoferus. This study indicates that these two Cimicomorpha can detect the presence of one another, and that they adjust their reproductive decisions, presumably to avoid potential competitive interactions.     

Influence of weed management on the abundance of thrips species (Thysanoptera) and the predatory bug,Orius niger (Hemiptera: Anthocoridae) in citrus mandarin

Applied Entomology and Zoology - Field trials were carried out in 2014 and 2015 in fields of Çukurova University Research and Implementation Area, Adana province, Turkey. The experiment was...     

Nutritional value of brine shrimp cysts as a factitious food for Orius laevigatus (Heteroptera: Anthocoridae)

Decapsulated cysts of the brine shrimp Artemia franciscana were assessed as a factitious food for rearing the anthocorid predator Orius laevigatus. Developmental and reproductive traits of O. laevigatus reared for a single generation on A. franciscana from three geographical locations or on gamma-irradiated eggs of the Mediterranean flour moth Ephestia kuehniella were compared. There was no effect of diet on nymphal survival but nymphal period on E. kuehniella eggs (12.2 days) was 0.7-1.6 days shorter than on the Artemia diets. The predator developed 0.5-1 day faster on cysts from San Francisco Bay (USA) than on cysts from Great Salt Lake (USA) or Macau (Brazil). Fecundity on brine shrimp cysts from different locations was similar to that on flour moth eggs (142-187 eggs/female). The biochemical composition of decapsulated cysts from San Francisco Bay was compared with that of E. kuehniella eggs. Depending on the type of analysis, Artemia cysts contained higher or similar amounts of protein as compared with E. kuehniella eggs, but amino acid patterns were generally similar. Flour moth eggs were almost three times richer in fatty acids than brine shrimp cysts, with some marked differences in fatty acid profiles. Because nutrient imbalances in a diet may be expressed only after several generations of rearing, the predator was cultured for three consecutive generations on A. franciscana cysts from San Francisco Bay. In the third generation on brine shrimp cysts, nymphs took 18% longer to develop, and adults were shorted-lived and about 60% less fecund than those maintained on E. kuehniella eggs. Brine shrimp cysts may be used as a supplement in the mass production of O. laevigatus but may not be a suitable food for long-term culturing of the predator.     

Distributions of western flower thrips (Thysanoptera: Thripidae) and its predatory bug Orius niger (Hemiptera: Anthocoridae) assessed by coloured sticky traps and plant samplings in cotton

The capturing efficiency of four coloured (yellow, green, white and blue) sticky traps, placed at the top, middle and bottom strata of cotton plants, was tested for the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and its predatory bug, Orius niger (Wolff) (Hemiptera: Anthocoridae), as well as spatial distributions of both insects on the plant in years 2006 and 2007. The white coloured trap was the most attractive to F. occidentalis and O. niger in the 2-year study. The blue coloured trap was the least attractive for Orius. The mean numbers of F. occidentalis and O. niger on the top plant parts (flowers and leaves) and in all coloured traps positioned on the upper parts of the plants were greater than those found in the lower two strata. Taylor's power law analysis showed that F. occidentalis and O. niger adults aggregated in the flowers or on the leaves. This study suggests that top flowers could be preferentially sampled to determine population densities of Frankliniella flower thrips and Orius species in cotton, and thus, sticky traps should be placed on the top level of plants. F. occidentalis: O. niger ratios in the flowers varied from 4 to 60 thrips per Orius adult in the three plant strata. This result may indicate that F. occidentalis experiences more predation from Orius.     

Effect of nymphal diet on adult predation behavior in Orius majusculus (Heteroptera: Anthocoridae)

The predatory bug Orius majusculus (Reuter) was reared on 2 different diets during the nymphal stages. The 1st group was exclusively offered eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), a standard diet for O. majusculus production. The 2nd group was exclusively offered 4th instars of the pea aphid, Acyrtosiphon pisum (Harris). Subsequently, adult predatory behavior in experimental arenas containing A. pisium was recorded using 2 video cameras. One camera permitted observation of the predator's contact with the prey, where the 2nd camera viewed the arena from above to record the path taken by O. majusculus adults before and after contact with prey. When O. majusculus were reared on aphids, adult bugs successfully located and consumed 55% of experimental prey and continued prey search behavior after each aphid meal. O. majusculus adults that had no experience of aphid predation as nymphs, did not prey on aphids in the experimental arena. The mean walking speed of this group of predators increased from 5.9 +/- 1.2 mm/s to 9.8 +/- 0.7 mm/s after contact or detection of prey, indicating that predators rapidly moved away from unfamiliar prey. Moreover, for egg-reared O. majusculus, all contacts between aphid and predator were lateral, along the side of the prey and were effectively repelled by an aphid kicking response. In contrast, 83% of attacks by aphid-reared O. majusculus were directed at the head or posterior abdomen for which the prey could not defend themselves adequately. When egg-reared O. majusculus were exposed to novel aphid prey for 1-8 d, the frequency of aphid attack increased significantly. We conclude that the standard diet used for rearing O. majusculus may adversely affect the efficiency of this predator as an agent of biological control.     

Pollen increases fitness and abundance of Orius insidiosus Say (Heteroptera: Anthocoridae) on banker plants

Banker plants are intended to enhance biological control by sustaining populations of natural enemies. Banker plants do this by providing alternative sources of food for natural enemies, such as pollen for omnivorous predators, thus decreasing the likelihood of their starvation and emigration from a cropping system when pest populations are low or absent. A banker plant system consisting of the Black Pearl pepper, Capsicum annuum ‘Black Pearl’, and the omnivorous minute pirate bug, Orius insidiosus Say (Hemiptera: Anthocoridae) has recently been proposed to improve biological control of thrips. Therefore, we studied how pollen from the Black Pearl pepper plant affects O. insidiosus fitness and abundance through a series of laboratory and greenhouse experiments. We found that a mixed diet of pollen and thrips increased O. insidiosus female longevity, decreased nymphal development time, and yielded larger females compared to a diet of thrips alone. Furthermore, O. insidiosus abundance was greater on flowering pepper plants than non-flowering pepper plants. From these results, we suggest that pollen from Black Pearl pepper banker plants could increase adult O. insidiosus abundance for the purpose of biological control in two ways: (1) reduce starvation and increase longevity of O. insidiosus when prey is absent; (2) enhance O. insidiosus fitness and fecundity when prey is present by mixing plant and prey diets. These results encourage future studies with the Black Pearl pepper as a banker plant for improving biological control of thrips in commercial greenhouses.