In honeydew beech forest in the South Island of New Zealand, introduced Vespula vulgaris wasps are now very abundant. Approximated biomass estimates indicate that Vespula (mostly V. vulgaris) biomass (mean estimate at peak = 3761 g ha, averaged over the year = 1097 g ha) is as great as, or greater than combined biomasses of birds (best estimate = 206 g ha), rodents (up to 914 g ha in some years...

The benefits of mutualistic interactions are often highly context dependent. We studied the interaction between the milkweed aphid Aphis asclepiadis and a tending ant, Formica podzolica. Although this interaction is generally considered beneficial, variation in plant genotype may alter it from mutualistic to antagonistic. Here we link the shift in strength and relative benefit of the ant-aphid ...

The effects of application of an artificial honeydew mixture of glucose, fructose and trehalose (GFT), honey and Bemisia tabaci nymph-extract as kairomonal sources in enhancing the foraging efficiency and performance of Eretmocerus sp. near furuhashii on cucumber plants were studied. Experiments were conducted in small greenhouses (4×3×3 m) using life table methods. Life table data indicated th...

BACKGROUND Invasive ants, such as the Argentine ant, have often been reported to facilitate honeydew-producing hemipteran pests such as mealybugs, which can be vectors of plant pathogens. Synthetic pheromones may offer a target-specific method to control such ants and consequently lower the abundance of honeydew-producing pests. Here we report the results of a trial to suppress Argentine ants i...

Examination of four species of aphid and four of whitefly showed that mannitol was present in each species of aphid, while sorbitol was present in the whitefly species. In the cotton aphid, Aphis gossypii Glover, the total body content of mannitol was considerably higher at noon than during the early morning. A similar increase in the sorbitol content of the silverleaf whitefly, Bemisia argenti...

Invasive ants often enter into facultative mutualisms that frequently lead to outbreaks of the hemipteran partner. Native ants may also enter into similar mutualisms but often these do not lead to outbreaks. However, field studies comparing the impact of an invasive and native ant on a honeydew-producing hemipteran are lacking. We monitored numerical changes of the black citrus aphid, Toxoptera...

The effects of different Cucurbita spp. rootstocks on melon cultivars belonging to different horticultural groups were studied by comparing grafted plants with non-grafted ones under greenhouse and open ®eld growing conditions. Winter melons (Cucumis melo L.) of the Inodorus group, cvs. `Thraki', `Peplo' and `Lefko Amynteou', and a summer melon of the Cantalupensis group, cv. `Kokkini Banana', ...

A series of experiments was set up to examine the effects of nitrogen on rice (Oryza sativa L.) resistance against Nilaparvata lugens (Stål) and Sogatella furcifera (Horváth). Egg laying by N. lugens was reduced on the indica variety IR60. Nymph biomass (N. lugens and S. furcifera) was also lower on IR60: this was associated with low honeydew production and a high proportion of xylem-derived ho...

In insects, Malpighian tubules are functionally analogous to mammalian kidneys in that they not only are essential to excrete waste molecules into the lumen but also are responsible for the reabsorption of indispensable molecules, such as sugars, from the lumen to the principal cells. Among sugars, the disaccharide trehalose is highly important to insects because it is the main hemolymph sugar ...

In this paper, the mutualistic relationship known as trophobiosis, which occurs convergently between ants and several groups of Hemiptera Sternorrhyncha and Auchenorrhyncha (formerly ‘Homoptera’) is reviewed. The main characteristics of ‘Homoptera’ and Formicidae which favor trophobiotic interactions, such as honeydew excretion by sapsucking insects, ant attendance and physiological needs of bo...