Good mothers, bad mothers, and the nature of resistance to herbivory in Solidago altissima

Abstract

Evidence of poor correspondence between an insect herbivore's oviposition preferences and the performance of its offspring has generally been attributed either to maladaptive behavior of the insect mother or inadequate measurement by the researcher. In contrast, we hypothesize that many cases of "bad mothers" in herbivores may be a byproduct of the hierarchical way natural selection works on resistance in host plants. Epistatic selection on the components of resistance (i.e., antixenosis and antibiosis) may generate negative genetic correlations between the resistance components, which could counteract the efforts of herbivores to oviposit on the best hosts for the performance of their offspring. In common garden and greenhouse experiments, we measured aspects of antixenosis and antibiosis resistance in 26 genets of tall goldenrod, Solidago altissima, against two common herbivores: the gall-inducing fly Eurosta solidaginis and the spittlebug Philaenus spumarius. Goldenrod antixenosis and antibiosis were positively correlated against E. solidaginis and negatively correlated against P. spumarius. Analogously, population-wide preference-performance correlations were positive for the gall flies and negative for the spittlebugs. Several natural history differences between the two insects could make gall flies better mothers, including better synchrony of the phenologies of the flies and the host plant, the much narrower host range of the gall flies than the spittlebugs, and the more sedentary lifestyle of the gall fly larvae than the spittlebug nymphs. If these results are typical in nature, then negative genetic correlations in antixenosis and antibiosis in plants may often result in zero or negative population-wide correlations between preference and performance in herbivores, and thus may be an important reason why herbivorous insects often appear to be bad mothers.

Biology of the Huanglongbing Vector <I>Diaphorina citri</I> (Hemiptera: Liviidae) on Different Host Plants

“…2), indicating that M. exotica was more suitable than H. apiculata for oviposition. Oviposition on H. apiculata was significantly lower than that obtained on M. exotica; however, this does not eliminate the possibility that H. apiculata can serve as a potential host for D. citri, because a low oviposition rate is not directly associated with impaired development of the offspring (Thompson 1988;Mayhew 2001;Wise et al 2008). In areas that lack its main host (M. exotica) or citrus groves, H. apiculata could help D. citri survive and may be important for insect dispersal and the epidemiology of HLB.…”

DUCKING AS A MEANS OF RESISTANCE TO HERBIVORY IN TALL GOLDENROD, SOLIDAGO ALTISSIMA

“…Females oviposit on apical-leaf buds, often after walking up and down the stem several times and making test punctures with their ovipositors in the bud (Uhler 1951, Walton et al 1990). Each gall contains one larva, but a single ramet occasionally forms up to three galls (Hess et al 1996, Wise et al 2008. Eggs hatch in about a week and spherical stem galls become visible within three weeks (Uhler 1951, Craig et al 2000.…”

Phenolics, rather than glucosinolates, mediate host choice of Bemisia tabaci MEAM1 and MED on five cabbage genotypes

“…Another study reported that survivorship of MEAM1 and MED nymphs was substantially lower and nymph developmental duration (egg-to-adult) was substantially longer on phenol-rich poinsettia than on cotton or tomato . Our present results indicate that there are significantly negative relationships between the total phenol contents of cabbage and the settling and oviposition preferences of high-quality food (Bernays, 1999;Bernays & Minkenberg, 1997;Gripenberg et al, 2010;Wise, Partelow, Everson, Anselmo, & Abrahamson, 2008). Although both MEAM1 and MED are generalist herbivores, MEAM1 may be more "specialized" than MED (Jiao et al, 2018).…”