Prey feeding increases water stress in the omnivorous predator Dicyphus hesperus

Abstract

The effects of water stress (produced by water deprivation and prey feeding) on plant feeding were investigated in the omnivorous predator Dicyphus hesperus Knight (Hemiptera: Miridae). The objective was to determine if prey feeding aggravated water deficits and thus increased plant feeding. We measured plant feeding in a factorial experiment where female D. hesperus were prepared for experiments by providing or withholding water and/or prey for 24 h. We then evaluated the amount of plant feeding on Nicotiana tabacum seedlings by the direct observation of insects at three different densities of the prey, Ephestia kuehniella eggs. The amount of plant feeding, as measured by frequency of plant feeding bouts and time spent plant feeding during observation, was significantly greater for water-deprived individuals than for those that had been provided with water. Individuals that had been provided with prey fed on plants at a significantly higher frequency than prey-deprived individuals at two of the prey densities used in the experiment. These results support the hypothesis that plant feeding in zoophytophagous Hemiptera facilitates prey feeding by providing water that is essential for predation.

Nitrogen and water limitations in tomato plants trigger negative bottom-up effects on the omnivorous predator Macrolophus pygmaeus

“…In addition, reduced water availability to plant may affect predatory behavior of the predator M. pygmaeus. Omnivorous predators belonging to Heteropteran sub-order must feed on plant tissues to acquire the water required for key biological processes, e.g., to produce saliva needed for the extra-oral digestion (Cohen 1998; Sinia et al 2004;Gillespie and Mcgregor 2000). We assume that in our study, a water deficit in plant tissues restricted the predator's ability to digest preyed eggs, which in turn, resulted in decreased longevity in the predator.…”

Development, survival and reproduction of Podisus nigrispinus (Dallas, 1851) (Heteroptera: Pentatomidae) with salt and amino acids solutions supplementary diet

“…The zoophytophagy facilitates the predation by supplying water for the extra-oral digestion of the prey (Sinia et al, 2004). This might occur for P. nigrispinus because individuals of this predator receiving water and prey had better development and reproduction than those with NaCl or amino acid solutions.…”

“…However, it is not clear if these predators obtain only water or also nutrients from plants (O´Neil and Wiedenmann, 1990;De Clercq and Degheele, 1992;Armer et al 1998). There are at least three hypotheses to explain the zoophytophagy in these insects: (1) equivalenceplants can supply nutrients obtained from prey when these are lacking; (2) facilitation -vegetable material supplies essential components to aid predation and (3) independence -vegetable material supplies essential nutrients not present in prey (Lalonde et al, 1999;Eubanks and Denno, 2000;Gillespie and McGregor, 2000;Sinia et al, 2004). The objective of this work was to study the effect of amino acids (commonly found in plants) and sodium chloride (NaCl) on survival, development and reproduction of the predator P. nigrispinus.…”

The cost of being an omnivore: mandible wear from plant feeding in a true bug

“…D. hesperus and related insects are closely allied with plant species that have sticky and hairy aerial parts (Cassis 1984). This species of insect requires food from both plant and animal sources for optimum development, and is dependent on water from plant sources (Gillespie and McGregor 2000;Sinia et al 2004 We ran three separate experiments to determine impact of plant feeding on our focal zoophytophage. In experiment one, we used a digital penetrometer to measure penetration resistance on pepper, tomato, tobacco, and mullein leaves and stems, and on green peach aphid, Myzus persicae adult apterae, syrphid larvae (Syrphus opinator) and D. hesperus fourth instar nymphs..…”