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Insects pests such as Mastigimas anjosi Burckhardt (Hemiptera: Calophyidae), native to Brazil, limit the establishment of commercial plantations of the tropical cedar Cedrela fissilis Vell. (Meliaceae), reducing growth and affecting tree shape. Insecticides have been used to suppress M. anjosi outbreaks, but sustainable alternatives should be developed to manage this pest. The objective of this work was to report, for the first time, the predator Atopozelus opsimus Elkins (Hemiptera: Reduviidae) preying on M. anjosi attacking C. fissilis trees in Minas Gerais State, Brazil. Trees of this plant were observed between Apr and May 2018 in Montes Claros, Minas Gerais State, Brazil. Atopozelus opsimus adults preyed on M. anjosi nymphs and adults, and fed on their honeydew. This predator did not eliminate the damage to C. fissilis, which may be related to the temperatures of the region, and which may have affected reproduction and increased its development period. [ABSTRACT FROM AUTHOR]

Nylanderia fulva (Mayr) (Hymenoptera: Formicidae), or tawny crazy ant, is an invasive ant from South America that is spreading in the southern US. Extremely large populations of this ant can inundate urban and natural landscapes, and efficient control methods are lacking. This study was conducted to determine if activity of N. fulva would decline after controlling the hemipteran honeydew-producers they were tending. Potted plants infested with cottony cushion scale (Icerya purchasi Maskell) (Hemiptera: Monophlebidae) were treated with 2 imidacloprid insecticide formulations, and changes in N. fulva survival and foraging behavior were monitored. There were fewer ant trails, lower trailing intensity, less foraging, and less nesting in potted plants treated with either product than in the control pots. The use of low application rates of systemic insecticide to reduce honeydewproducing hemipterans, such as cottony cushion scale, could be an important component of the integrated pest management of N. fulva. [ABSTRACT FROM AUTHOR]

Honeydew produced by hemipterans mediates mutualistic interactions between ants and hemipterans. Previous studies demonstrated that the mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) and the aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) produce abundant honeydew and attract a large number of tending ants. Ghost ants, Tapinoma melanocephalum (F.) (Hymenoptera: Formicidae), show a significant preference for mealybug honeydew over aphid honeydew. Although many studies have indicated that the honeydew produced by hemipterans plays an important role in ant-hemipteran interactions, we know little about what triggers ants' foraging preferences. Our results showed that the honeydew produced by both mealybugs and aphids contained fructose, sucrose, trehalose, melezitose, raffinose, and rhamnose. There were no significant difference in the concentrations of the various sugars between mealybugs and aphids, except sucrose. Xylose was present only in mealybug honeydew, and glucose was present only in aphid honeydew. We also found no substantial difference in the excretion frequency and the total weight of honeydew produced per 24 h between mealybugs and aphids. Ghost ants preferred sucrose. In addition, attractiveness of sucrose solutions increased significantly with increasing concentration. These results suggest that sucrose is the trigger for ghost ants' honeydew preference. [ABSTRACT FROM AUTHOR]

Infection of Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), with ' Candidatus' Liberibacter asiaticus (Las), the causal pathogen of citrus greening disease or huanglongbing, increases psyllid susceptibility to insecticides. Diaphorina citri populations in citrus occur year-round in tropical and sub-tropical habitats, and thus insecticide applications for managing this plant disease vector occur over a wide temperature range (10-40 °C). During the winter season, D. citri is occasionally exposed to periods of freezing temperatures, when temperatures fall below -6.5 °C. In this investigation, we compared insecticide susceptibility of uninfected and Las-infected D. citri at various temperatures (20-37 °C). Cold-acclimated (6 ± 1 °C) D. citri adults were less susceptible to neonicotinoid insecticides as compared with non-acclimated controls, but this trend was not observed for other insecticides tested. A positive correlation between temperature and percentage mortality caused by chlorpyriphos, imidacloprid, spinetoram, and thiamethoxam was found irrespective of infection status when evaluated at temperatures ranging between 20 and 37 °C. In contrast, a negative correlation between temperature and percentage mortality was observed for fenpropathrin for both infected and uninfected psyllids. Glutathione S-transferase levels were negatively correlated with temperature, whereas levels of cytochrome P450 and general esterase were not correlated with temperature fluctuations. These results indicate that altered insecticide susceptibility due to temperature may not be related to glutathione S-transferase, cytochrome P450, and general esterase levels. Diaphorina citri adults that carried the Las bacterium had reduced CYP4 transcript and protein levels, and ingested less than uninfected counterparts, as measured by the production of honeydew. Diaphorina citri adult feeding was greatest at 32 °C within the temperature range tested. Overall, annual temperature fluctuation does not appear to be a major factor impacting management of D. citri. [ABSTRACT FROM AUTHOR]

Mutualism between ants and honeydew-producing hemipterans is a common phenomenon in ecosystems, and interactions between ants and hemipterans have been extensively studied. The invasive solenopsis mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), and the ghost ant, Tapinoma melanocephalum (F.) (Hymenoptera: Formicidae), are widely distributed in China. Previous studies showed that the ghost ant can promote the fitness of the invasive mealybug when natural enemies of the mealybug are excluded. In this study, we investigated the interactions between the ghost ant and the invasive solenopsis mealybug when the mealybug's natural enemies were included. Our results indicated that the honeydew produced by mealybugs facilitated colony growth of the ghost ant significantly more than by allowing them to feed on the mealworm, Tenebrio molitor L. (Coleoptera: Tenebrionidae). Tending by the ghost ant increased mealybug survival on the plants when six-spotted zigzag lady beetle larvae, Cheilomenes sexmaculata (Fabricius) (Coleoptera: Coccinellidae), were present. Both lady beetle adults and the mealybug parasitoid, Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae), showed strong avoidance responses to ghost ants. The fecundity of lady beetle adults and the hatching rate of their eggs were significantly reduced by ghost ants. Also ghost ant tending appeared to negatively affect parasitoid performance. The number of mummified mealybugs on Hibiscus rosa-sinensis L. (Malvales: Malvaceae) in the presence of ghost ants was significantly less than the number without ants. [ABSTRACT FROM AUTHOR]

Honeydew is a carbohydrate-rich solution excreted by phloem-feeding insects such as aphids. Ants often consume this substance and, in return, protect aphids from natural enemies. This indirect benefit of ant--aphid mutualisms to aphids (reduced predation) has been examined extensively. Few studies, however, have quantified the direct benefits that aphids may gain from the mutualism. We conducted greenhouse experiments to estimate the direct benefits that cotton aphids, Aphis gossypii (Glover) (Hemiptera: Aphididae), receive from their mutualistic relationship with red imported fire ants, Solenopsis invicta (Buren) (Hymenoptera: Formicidae). We compared population growth and alate production between ant-tended and untended aphid colonies in the absence of natural enemies. We found strong evidence that cotton aphids receive direct benefits from their relationship with fire ants. After 12 days, aphid colonies with tending ants were 46% larger than their non-tended counterparts. Alate production, however, was not affected by ant tending, suggesting that a reduction in dispersal did not explain the ant effect on aphid population growth. We hypothesize that the increase in aphid population size results from altered feeding behaviors in the presence of ants. This study suggests that there may be constant selection for this mutualism even in the absence of aphid natural enemies because aphids gain direct benefits. [ABSTRACT FROM AUTHOR]

Nylanderia fulva (Mayr) (Formicidae) is an invasive pest ant that has been reported in Florida, Texas, Louisiana and Mississippi. Workers tend various honeydew producing hemipterans in Florida landscapes and natural areas. We sought to understand the seasonal foraging activities of N. fulva and its relationship with honeydew producing hemipterans. Twenty-two hemipteran species were collected from 15 different plant hosts sampled in Florida from Jul 2010 to Jul 2012. The relative density of hemipterans on 4 plant species [live oak (Quercus virginiana Mill.; Fagales: Fagaceae), holly (Ilex cornuta Lindl.; Aquifoliales: Aquifoliaceae), magnolia (Magnolia grandiflora L.; Magnoliales: Magnoliaceae), and sugarberry (Celtis laevigata Willd.; Urticales: Ulmaceae)] was compared to the relative density of N. fulva at the base or stem of the selected plants. The number of N. fulva and hemipterans on each plant species was positively correlated from spring through fall. Both N. fulva and hemipteran populations increased from May to Sep and decreased from Oct to Apr. In addition, Cinara juniperivora (Wilson) (Hemiptera: Aphididae) on southern red cedar and Toumeyella liriodendri (Gmelin) (Hemiptera: Coccidae) on magnolia were covered with carton shelters presumably constructed by N. fulva, suggesting that this ant potentially protects certain hemipterans species. [ABSTRACT FROM AUTHOR]

Associations between ants and Hemiptera are common in the families Membracidae, Coccoidea and Aphidoidea, but there are only a few cases of ants using honeydew of Cicadellidae species. We surveyed plants of Roupala montana Aubl. (Proteaceae) in the cerrado area (savanna like vegetation) in the Federal District (Brazil) during the rainy season of 2006 and 2007. In this period the plants produce new leaves, which are consumed by the nymphs of a probable new species of Rotundicerus (Cicadellidae: Idiocerinae). The nymph groups are of variable size, with a mean of 20 individuals. We found 83% of them being tended by ants. A total of 21 ant species was documented, with predominance of Camponotus spp. and Cephalotes spp. There is a clear species turnover of ants on the nymph groups and attendance is not continuous in most of the cases, suggesting an opportunistic association between ants and Rotundicerus sp. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the method for short-term rearing of Asian citrus psyllid (ACP) and for accumulating its honeydew excretions. The study has evaluated the data gathered from the rearing of ACP with the use of detached mature citrus leaves for adults and detached young terminal shoots for nymphs. The study has found out that the survival and adult emergence of nymphs were higher when reared on younger leaves than on mature leaves.