Control of spotted wing drosophila,Drosophila suzukii,by specific insecticides and by conventional and organic crop protection programs

Spotted wing drosophila, Drosophila suzukii, is an invasive insect pest that has spread into many fruit production regions of the world. Strategies to protect fruit from infestation by this insect are currently dominated by insecticide applications, so producers need information on relative efficacy and residual activity of insecticides to be able to select effective treatments. Semi-field bioassays in which highbush blueberry shoots with berries were treated then exposed to adult flies at different times after application revealed that fresh residues of organophosphate, pyrethroid, and spinosyn insecticides have strong initial activity on flies, with varying levels of residual protection against fruit infestation. An organic pyrethrum insecticide was not effective, whereas the neonicotinoid insecticide acetamiprid was found to have activity for up to five days. Rainfall after application greatly reduced the level of control achieved by some insecticides. Field-scale evaluation of conventional and organic spray programs initiated in response to capture of D. suzukii flies in monitoring traps indicated that both types of management provide significant fruit protection compared to untreated fields, with less larval detection in the conventionally-produced berries.     

Effect of a plastic rain shield on fruit cracking and cherry diseases in Greek orchards

The use of plastic rain shields is a very effective method to control fruit cracking in cherry trees. In this study, the effect of plastic rain shields on fruit cracking and fruit decay was investigated in different sweet cherry cultivars. The results showed that the percentage of fruit cracking and fruit decay was significant higher in uncovered than covered cherry trees. Fungi of the genus Monilinia were the main pathogens causing fruit decay in cherry fruits. In fruit with symptoms of cracking, fungi of the genus Alternaria predominated. Finally, the effect of plastic rain shield on the development of the disease Shot Hole (Wilsonomyces carpophilus) was examined. In most of cases, the percentage of the Shot Hole disease was higher in covered than uncovered cherry trees. Differences were found among cultivars.Generally, the use of plastic rain shields is a very effective method to control fruit cracking and fruit decay on cherry trees, but they should be removed during dry periods to reduce the risk of developing of Shot Hole.     

Marketplace Analysis Demonstrates Quality Control Standards Needed for Black Raspberry Dietary Supplements

There is currently no standard for the minimum anthocyanin concentration a black raspberry dietary supplement must contain for legal sale in the US. All consumer available black raspberry products (n?=?19), packaged as dietary supplements or otherwise prepared (freeze-dried whole and pre-ground powders), were purchased and analyzed for their anthocyanin composition and concentration. Seven of the 19 samples contained no anthocyanins from black raspberry fruit, while three of those seven (without black raspberry fruit) had no anthocyanins of any kind. There was a wide range of anthocyanin concentration within the remaining products (18.1–2,904.8 mg/100 g; n?=?12). When expressed as per capsule or per ～1 teaspoon, concentration ranged from 0.1 to 145.2 mg (average 28 mg; n?=?12). Until US dietary supplement labeling comes under regulatory oversight similar to food guidelines, foods are a more dependable source for dietary phenolics than supplements.     

Differential attraction ofDrosophila melanogaster Meig. to potato tissue infected with two varieties ofErwinia carotovora

Experiments were conducted to determine ifDrosophila melanogaster Meig. was differentially attracted to decaying potato tissue infected withErwinia carotovora var.carotovora as compared toE. C. var.atroseptica because these insects transmit each bacterium at a different rate in nature. The results of olfactometer tests demonstrated that potato tissue infected with the two varieties of the organism do not differ in their attractiveness toD. melanogaster; also, that attraction of these flies to healthy potato tissue was not significantly different than the attraction to infected tissue.     

Response of two tephritid species, Bactrocera oleae and Ceratitis capitata, to different emission levels of pheromone and parapheromone

Attractants and pheromones are commonly used in integrated pest management programs in crop systems. However, pheromone dispensers employed in monitoring traps and lure and kill devices are not usually well studied and attractants are released at uncontrolled rates leading to low treatment efficacies and misleading monitoring estimations. Fruit flies are pests of economic importance and monitoring is essential in order to program insecticidal treatments. Moreover, lure and kill techniques are being increasingly used, but the cost of these techniques depends on the number of required traps and, therefore, on the efficacy of the attractants. Ceratitis capitata and Bactrocera oleae are the two main fruit flies in Mediterranean countries, and the effect of different doses of trimedlure and spiroacetal on fly attraction has been studied. Results showed that a release rate over 1.28 mg/day of spiroacetal reduces B. oleae attraction and emission values over 2.4 mg of trimedlure per day did not increase C. capitata catches. Under the environmental conditions of our study, an optimum release rate for pheromone attraction in B. oleae was determined. Emission values over this optimum level reduced B. oleae attraction. However, when a parapheromone was used with C. capitata, a fruit fly of the same family, the optimum emission value was not found and higher quantities of parapheromone attracted the same number of flies. The saturation effect of high concentrations of pheromone and parapheromone is discussed.     

Effect of simulated rainfall on the effectiveness of insecticides against spotted wing drosophila in blueberries

The current spotted wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae) management strategy relies on routine application of insecticides during the fruit ripening and harvesting period. The amount and frequency of insecticide spray needed to maintain continuous protection of fruits may depend on a variety of factors including the level of rainfall. Studies were conducted to determine the effects of simulated rainfall (0, 12.5, 25 and 37.5 mm) and adjuvant – Nu Film (with and without) on the residual efficacy of commonly used insecticides against D. suzukii in blueberries during the fruiting season of 2014 and 2015. Spray applications were made using an air-assisted backpack (2014) or airblast (2015) sprayer. Insecticide spray residues were allowed to dry for ∼2 h before simulated rainfalls were applied using central pivot irrigation system. Semi-field bioassays were conducted to assess mortality at 1, 3 and 7 days after treatment (DAT). Results showed that simulated rainfall caused a significant reduction in D. suzukii mortality in all chemical treatments, particularly at 1 and 3 DAT in the 2014 study, and at 1 DAT in the 2015 study. In general, higher rainfall resulted in lower mortality in 2014, however such a clear trend was not observed in 2015. Addition of adjuvant, Nu Film 17, significantly increased mortality at 3 DAT in the zeta-cypermethrin treatment with 25 mm of simulated rainfall (2014). In 2015, the addition of Nu Film P significantly increased mortality at 1 DAT in the spinetoram and spinosad treatments with 12.5 mm, and in the malathion treatment with 25 mm of simulated rainfall. These results suggest that although frequent rainfall incidents increase the need for more frequent spray of insecticides, addition of adjuvants helps to prolong the residual efficacy of some insecticides.     

Season-long programs for control of Drosophila suzukii in southeastern U.S. blueberries

Drosophila suzukii is an invasive insect pest which has major impacts on small fruit production throughout North America. Current control programs use frequent applications of broad-spectrum insecticides. To prevent resistance, modes of action must be rotated. This study examines the acute and residual efficacy of rotational treatment programs designed to meet the needs of commercial growers in the southeastern United States, a region which experiences significant precipitation throughout the growing season. All insecticide applications had greater adult acute mortality than controls, and some had residual efficacy for three or more days after treatment. Programs had no residual effects at seven days after treatment. Within programs, organophosphates (phosmet and malathion) and pyrethroids (zeta-cypermethrin and fenpropathrin) were the most effective. Some programs also resulted in less offspring production by D. suzukii in bioassays and reduced field infestation compared to controls. Results show that effective, season-long rotational chemical treatment programs can be designed to minimize crop damage, meet exportation requirements and manage for resistance. Understanding the effect of regional climate on the performance of individual insecticide treatments and their efficacy will be critical for widespread implementation of effective control programs for D. suzukii.     

Color preference,seasonality, spatial distribution and species composition of thrips (Thysanoptera: Thripidae) in northern highbush blueberries

We investigated color preference, seasonal abundance, spatial distribution and species composition of thrips in northern highbush blueberries, Vaccinium corymbosum L., in New Jersey (USA). White sticky traps were more attractive to thrips compared with yellow or blue traps. Thrips captures using white sticky traps showed that their flight activity begins 20–30 d after the onset of flowering, with 10, 50 and 90% of trap captures observed at 383, 647 and 1231 degree-day accumulations, respectively (10 °C base temperature). Two methods were used to study thrips distribution within a blueberry bush. First, white sticky traps were placed within the bush canopy at three different heights. The highest numbers of thrips were caught on traps in the middle and top one-third of the canopy while the lowest numbers were caught in the bottom one-third. A second method determined the distribution of thrips on the blueberry plant at different heights and phenological stages. The highest numbers of thrips were found on young leaves at lower parts of the canopy, whereas flowers and fruit had fewer thrips and none were found on buds; these thrips were identified as, Scirtothrips ruthveni (88% of adults) and Frankliniella tritici (12%). The distribution of thrips within a blueberry planting was investigated using an evenly-spaced grid of white sticky traps in combination with on bush beating-tray samples. Thrips counts from traps correlated with direct counts on the bush across the entire blueberry field (macro-scale level); however, within the field (micro-scale level), there was no correlation between the number of thrips on traps and on individual bushes near traps. Early in the season, trap counts were higher on bushes closer to the forest, indicative of movement of thrips from wild hosts into blueberry fields. However, this was not the case for direct on bush counts or trap counts for the later part of the season, where there was no clear forest “edge” effect. Percent fruit injury due to thrips feeding was low, and it correlated with thrips counts on bushes but not from counts on traps. Overall, our data show that thrips counts on sticky traps need to be interpreted with care because these numbers weakly correlated with the numbers of thrips on bushes at the micro-scale level and percent fruit injury; however, they can be useful predictors of thrips activity across entire blueberry fields (macro-scale).     

An Alien in the Group: Eusocial Male Bees Sharing Nonspecific Reproductive Aggregations

Sexual selection predicts that individuals competing for access to sexual partners should maximize their chances of mating by looking for sites where the chances of finding partners are more likely to occur. However, males of stingless bees have been observed sharing nonspecific reproductive aggregations. This uncommon behavior appears to confer no obvious increase of individual fitness. It has been suggested that this reproductive strategy is due to the similarity between male odors common to different stingless bee species. Cuticular hydrocarbons (CHCs) are candidate odors of interest because their nonvolatile pheromone nature allows them to play an important role in sexual behavior and species recognition. Here, we review the literature to evaluate whether any phylogenetic patterns exist among male stingless bees that aggregate with closely or distantly related species. We also compared the CHC profiles of males of Neotropical stingless bee species (Plebeia sp. Schwarz, Trigona spinipes (F.), Tetragona clavipes (F.), Nannotrigona testaceicornis (Lepeletier), Scaptotrigona aff. depilis (Moure), Tetragonisca angustula (Latreille), and Melipona subnitida (Ducke) to reveal any chemical similarities among their male odors. We found males of 21 stingless bee species involved in interspecific interactions mainly from Neotropical and Indo-Malayan/Australasian regions. Alien males did not necessarily visit host aggregations of closely related species. Furthermore, the CHC profiles of different studied species were very distinct from each other and do not overlapped at all. It is unclear yet why this apparently nonadaptive behavior carried out by some stingless bee males.     

Improvement of Hanseniaspora uvarum biocontrol activity against gray mold by the addition of ammonium molybdate and the possible mechanisms involved

The efficacy of Hanseniaspora uvarum against gray mold by adding ammonium molybdate (NH₄–Mo) and the mode of actions were evaluated. The results showed that H. uvarum at 1 × 10⁶ CFU ml⁻¹ plus 1 mmol l⁻¹ NH₄–Mo greatly reduced gray mold in grape fruits. NH₄–Mo at concentrations of 1, 5, 10 and 15 mmol l⁻¹ significantly inhibited spore germination and mycelium growth of Botrytis cinerea. Population growth of H. uvarum was markedly inhibited by NH₄–Mo at 5 mmol l⁻¹in vitro and not affected by addition of NH₄–Mo at 1 and 5 mmol l⁻¹ in wounds combination of NH₄–Mo and H. uvarum induced higher activities of peroxidase (POD), polyphenoloxidase (PPO), phenylalanine ammonialyase (PAL), superoxide dismutase (SOD), catalase (CAT) and β-1,3-Glucanase than individual application of H. uvarum or NH₄–Mo. The enhancement of disease control may be directly because of the inhibitory effects of NH₄–Mo on spore germination and mycelial growth of B. cinerea in vitro, and indirectly because of the induced defense reactions by NH₄–Mo in grape berries.     

Effect of Pichia membranaefaciens on ROS metabolism and postharvest disease control in citrus fruit

The yeast Pichia membranaefaciens has antagonistic effects against a wide range of phytopathogenic fungi that cause postharvest fruit decay. This work evaluated the effects of P. membranaefaciens on the reactive oxygen species (ROS) metabolism and disease control in harvested citrus fruit (Citrus sinensis L. Osbeck). The lesion diameter caused by Penicillium italicum and Penicillium digitatum on citrus fruit was remarkably reduced when the fruit was point-inoculated or dipped in a suspension of P. membranaefaciens at 1 × 10⁸ CFU mL⁻¹. The application of P. membranaefaciens on citrus fruit enhanced the activity of superoxide dismutase, ascorbate peroxidase, and glutathione reductase, as well as the levels of hydrogen peroxide, the superoxide anion and glutathione, but inhibited the decreasing ascorbic acid content. Furthermore, catalase activity was decreased by the same treatment. These results indicated that yeast treatment induced the synthesis of antioxidant enzymes which might have antagonistic effects against postharvest green and blue mold infection in citrus fruit.     

Bird damage to select fruit crops: The cost of damage and the benefits of control in five states

Fruit loss to birds is a long-standing and costly problem for many producers. We conducted a survey of Honeycrisp apple, blueberry, cherry, and wine grape growers in California, Michigan, New York, Oregon, and Washington to estimate costs of bird damage and benefits of bird damage management. We also assessed grower perceptions of impacts on profits and effectiveness of bird management techniques. Current yield-loss estimates provided by growers and market price data were used to monetize current bird damage in each crop and growing region. Data on expected damage without management were used to estimate the benefits of bird damage management as it is currently being employed in the different crops and growing regions. We estimated that current bird damage costs per hectare ranged from $104 in Oregon tart cherries to $7267 in Washington Honeycrisp apples. Estimated benefits of bird management ranged from $299 per hectare in Oregon tart cherries to $36,851 in California blueberries. Aggregate bird damage in the five crops and states was estimated at $189 million, and the aggregate benefits of managing that damage were estimated at $737 million to $834 million. Growers viewed most techniques for bird damage management as ineffective, or only slightly effective, and a majority of blueberry and sweet cherry growers viewed bird damage as having a significant impact on profits. Enhancing the effectiveness of bird damage management would increase both the efficiency and profitability of fruit production.     

Biocontrol action mechanisms of Cryptococcus laurentii on Colletotrichum gloeosporioides of mango

Mechanisms of action and effectiveness of the antifungal yeast Cryptococcus laurentii [(Kuff.) C.E. Skinner] strain L5D, were examined against the causal agent of anthracnose Colletotrichum gloeosporioides ((Penz.) Penz. & Sacc.) in mango (Mangifera indica L.). C. laurentii showed a high antagonistic potential in vivo, with significant inhibition of anthracnose (75.88%). Different mechanisms of action were examined in C. laurentii among them competition for nutrients, specifically for sucrose (p < 0.05). Scanning Electron Microscopy (SEM) showed that the yeast biofilm adheres to the fruit and to C. gloeosporioides hyphae showing competition for space; C. laurentii was not washed off from treated Colletotrichum hyphae as observed with SEM. According to statistical analysis, only nagase and chitinase were significantly stimulated on wounded fruit. Activity of all three hydrolytic enzymes was detected in vitro but only nagase was induced by addition of autoclaved pathogen mycelium. Treated wounds with the yeast biocontrol stimulated glucanase activity and suppressed chitinase activity on fruit wounds with or without presence of autoclaved pathogen mycelium but did not affect nagase significantly (p = 0.05). Parasitic activity of yeast on pathogen was not detected.     

Quality characteristics of red raspberry fruit spread made with four sweeteners

Red raspberry fruit spreads sweetened with sugar (S) or raspberry, red grape, or apple juice concentrates were processed by inversion and analyzed for chemical, physical, and sensory properties at 1, 12, and 24 weeks. All pH values were between 3.0 and 3.5 while all a_w were above 0.81. Samples were dark red but became duller over time. Viscosities and total solids were lower (p<0.05) in juice sweetened products than in S. Sensory evaluations improved over time for all samples, but were always higher (p<0.05) for S. Mold was detected in all samples at 24 weeks. Acceptable products were prepared using fruit juice concentrates but inversion processing was not recommended for fruit spread preparation.     

References for “musty” odor notes in sensory analysis of grain sorghum

The presence of off-odors, such as “musty” or “sour,” in grain sorghum decreases the value of the product. Sensory analysis and head space-solid phase micro extraction-gas chromatography-mass spectrometry were conducted on raw sorghum to identify chemicals that would be suitable as sensory references for musty odors in this grain. Two groups of musty grain sorghum notes were differentiated: “dry” and “wet” musty sorghum. Musty sorghum with “wet” odor notes had other off-odor notes described as earthy/damp or moldy. The compounds found in musty sorghum grain were studied as “musty” note standards to use for the development of sensory references. Seven potential compounds were chosen, and a shelf life study was completed on the sensory references. Geosmin (0.1 mg/kg), 1,2-dimethoxybenzene (100 mg/kg), 3-octanone (100 mg/kg), and 1,2,4-trimethoxybenzene (100 mg/kg) were identified as potential candidates to help reproduce musty odor notes when added to clean fresh sorghum grain.     

Differences in Antennal Sensillae of Male and Female Peach Fruit Flies in Relation to Hosts

Antennal sensillae of male and female peach fruit flies, Bactrocera zonata (Saunders) (Diptera: Tephritidae), obtained from three different host fruit species (guava, Psidium guajava L. (Myrtales: Myrtaceae); peach, Prunus persica (L.) Stokes (Rosales: Rosaceae); and orange, Citrus sinensis (L.) Osbeck (Sapindales: Rutaceae)), were studied with scanning electron microscopy. This study was carried out to describe the different types of sensillae present on the three antennal segments (scape, pedicel, and flagellum or funiculus) of both sexes of B. zonata on different host fruit. The antennal segments of females tended to be larger than those of males feeding on peach and guava fruit. On orange, both sexes were similar (no significant differences were found). The first two antennal segments, scape and pedicel, are reinforced by some bristles and have different types of sensillae, including trichoid I, II, S; basiconic II; and sensilla chaetica in different numbers on different host fruit species. Numerous microtrichia, as well as trichoid (I, II), basiconic (I), clavate, and coeloconic (I, II) sensillae were observed on the funiculus with a great variation in number and length. As a result of feeding on different hosts, differences were found between sexes and some plasticity in size, number, distribution, and position of some sensillae, including trichoid, basiconic, chaetica, and clavate on the antennae of the female B. zonata. These sensillae were significantly larger in females. Also, some morphological and morphemetric differences have been found according to their feeding on different host fruit.     

Parasitism,Emergence, and Development of Spalangia endius (Hymenoptera: Pteromalidae) in Pupae of Different Ages of Bactrocera cucurbitae (Diptera: Tephritidae)

The wasp Spalangia endius Walker (Hymenoptera: Pteromalidae) is a major parasitoid of the pupae of fruit flies, which are a common agricultural pest. An understanding of this intricate host–parasitoid interaction could provide basic information necessary for the sustainable integrated biological control of fruit flies. In this study, we investigated the effect of S. endius on different-aged pupae of the melon fly Bactrocera cucurbitae Coquillett by using choice and nonchoice tests under laboratory conditions. We showed that S. endius females oviposited, and their progeny successfully developed, in different-aged pupae of B. cucurbitae regardless of the method of exposure. There was an oviposition preference for 3–5-d-old pupa. The highest mean percentage parasitism occurred on 4- and 5-d-old hosts, followed by 2- and 3-d-old hosts. The average development time for both males and females was significantly longer in 6–7-d-old hosts than in the younger host stages. Adult females that developed from younger host pupae (2–5-d old) were significantly heavier than those from older host pupae (6–7-d old), and they also lived longer. The sex ratio (proportion of females) of the parasite progeny decreased with an increase in host age. Host mortality also decreased gradually as the pupal age increased. The differences in development time, body weight, and longevity between females and males were significant. These results suggest that S. endius is a good candidate for the biological control of B. cucurbitae.     

Host suitability of three avocado cultivars (Persea americana Miller: Lauraceae) to oriental fruit fly (Bactrocera (invadens) dorsalis (Hendel) (Diptera: Tephritidae))

The oriental (invasive) fruit fly Bactrocera (invadens) dorsalis (Hendel) (Diptera: Tephritidae) has invaded Africa and is currently established in over 30 countries and has caused in massive fruit losses. Avocado (Persea americana Miller) is among the fruit with which the pest is associated. The aim of the study was to determine the host status of a ‘black-skinned’ cultivar “Hass” and two ‘green-skinned’ cultivars “Pinkerton” and “Fuerte” to B. (invadens) dorsalis. In the laboratory study conducted in Kenya in 2012 and 2013, punctured and unpunctured recently-harvested fruit were exposed to sexually-mature fruit fly in ‘no-choice’ experiments. B. (invadens) dorsalis readily developed in the punctured fruit but not in the uncompromised fruit (fruit not damaged by insects or handling). This result was confirmed in Tanzania in 2013 where flies were introduced to unpunctured fruit. In the field studies the fruit of each cultivar were caged in situ with flies for 72 h. On dissection only fruit damaged by false codling moth (Thaumatotibia leucotreta (Meyrick)) were found to harbor B. (invadens) dorsalis. In the light of these results the risk imposed for “Hass”, “Pinkerton” and “Fuerte” by B. (invadens) dorsalis is negligible under standard export conditions. The findings of this study and the implications to regional and international trade are discussed.     

Contributions of visual cues to cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), resistance in novel host genotypes

Herbivorous insects can demonstrate great selectivity among visual cues. The cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae) (syn. Ceutorhynchus assimilis (Paykull)) is also influenced by visual cues. Here, we present results of a study examining the attractiveness of flowers and foliage of Sinapis alba (a suboptimal host for larval development), Brassica napus (an excellent host for larval development) and novel lines derived from S. alba x B. napus; several of these have been demonstrated to be resistant in field and laboratory tests. Attractiveness, reflectance properties and resistance demonstrated in field trials were related. Responses to host plants differed among plant genotypes and were related to the amounts of UV and yellow reflected from flowers. Moderate UV reflectance greatly increased the attractive effects of yellow. Fewer weevils responded to test plants with greater or lesser floral UV reflectance.     

Effect of a Tart Cherry Juice Supplement on Arterial Stiffness and Inflammation in Healthy Adults: A Randomised Controlled Trial

Tart cherries are a particularly rich source of anthocyanins. Evidence indicates that dietary intake of anthocyanins is inversely associated with arterial stiffness. We conducted an open-label randomised placebo controlled study to determine whether a tart cherry juice concentrate (Cherry Active®) reduced arterial stiffness, inflammation and risk markers for cardiovascular disease in 47 healthy adults (30–50 years). Participants consumed 30 ml of cherry concentrate diluted to a volume of 250 ml with water or the same volume of an energy matched control drink daily for six weeks. Measurements were taken at baseline and at the end of the intervention. There was no effect of the intervention on arterial stiffness (P?=?0.218), c-reactive protein (P?=?0.220), systolic blood pressure (P?=?0.163), diastolic blood pressure (P?=?0.121), total cholesterol (P?=?0.342) and high density lipoprotein cholesterol (P?=?0.127). At the end of the intervention, plasma antioxidant capacity (measured as the ferric reducing ability of plasma (FRAP)) was significantly higher in the intervention group than the control group (P?=?0.012). We conclude that a tart cherry juice concentrate rich in anthocyanins has no effect on arterial stiffness, c-reactive protein and risk markers for cardiovascular disease, but evokes a minor increase in antioxidant status in healthy adults.