Leaf abscission phenology of a scrub oak: consequences for growth and survivorship of a leaf mining beetle

Abstract

Brachys tessellatus is a leaf-mining beetle that attacks Quercus laevis (turkey oak), a deciduous scrub oak in the fall line Sandhills of the southeastern United States. This oak species varies substantially in leaf abscission phenology. In the fall of 1994 we examined leaf abscission patterns at three sites in central South Carolina and found that leaves containing active miners abscised earlier than leaves without active miners. To quantify the effect of leaf abscission phenology on the survivorship and body size of leaf miners within the abscised leaves, we marked naturally and manually abscised leaves, left leaves on the ground to over-winter, and then collected leaves before beetles emerged the following spring. We found that beetles inside leaves that were abscised early in the season were more likely to be killed by predators, and that they produced smaller pupae than beetles within leaves abscised later in the season. We also evaluated the relationship between adult beetle body size and fecundity; body size of B. tessellatus is positively correlated with lifetime fecundity and daily oviposition rate indicating that effects of leaf-abscission phenology on beetle body size likely translate into effects on beetle fitness. We discuss how B. tessellatus has adapted to variation of leaf abscission phenology of oaks by evolving developmental plasticity that permits successful completion of larval development over a range of season lengths.

Perfect is best: low leaf fluctuating asymmetry reduces herbivory by leaf miners

“…Eggs are deposited singly on the upper surface of the leaves and after hatching the larvae mine into the mesophyll creating distinct, characteristic damage. Contrary from what happens in South Carolina (Waddell et al 2001) Brachys in our study sites go through two generations instead of just one. The first mines appear in early April and remain active until late June, when larvae complete their development and pupate inside the mines.…”

“…Pupation and overwintering of this second generation occurs within the leaves after they have senesced and abscised from the tree. New adults emerge from the leaf litter in the following spring (Waddell et al 2001). Turkey oak leaves are also attacked by a vast array of herbivores, such as the leaf roller weevil Homoeolabus analis (Coleoptera: Atellabidae), the eastern buck moth H. maia, the white tussock moth Orgyia leucostigma (Lepidotpera: Lymantriidae) and other leaf miners such as Stigmella (Lepidoptera: Nepticulidae) and Cameraria (Lepidoptera: Gracillariidae).…”

Alteration of the phenology of leaf senescence and fall in winter deciduous species by climate change: effects on nutrient proficiency

“…The progressive increase in resorption as leaf senescence is delayed may have other causes. For example, leaves tend to fall earlier when affected by various stresses, such as water stress (Killingbeck, 2004), biotic stress (Waddell et al, 2001), or ozone stress (Kasurinen et al, 2012), and leaves are less proficient at resorption under water stress (Killingbeck, 2004) and herbivory (Silla et al, 2008), which may be the case for leaves falling early within a stand. We are of the opinion that nutrient resorption is not inherently determined by the date of leaf senescence and that the appropriate approach is to ascertain if the factor altering the phenology of leaf senescence affects any physiological step of the process of leaf senescence that regulates the resorption of nutrients.…”

Revisión de las influencias de los insectos minadores de hojas en sus plantas huésped

“…First, premature leaf fall stops the further development of young leaf miner larvae lessening leaf miner numbers in the next generation. The falling of mined leaves earlier than unmined leaves may attribute high mortality of some leaf miners (Faeth et al, 1981;Stiling et al, 1987Stiling et al, , 1991Auerbach & Simberloff, 1989;Preszler & Price, 1993;Connor et al, 1994;Waddell et al, 2001), since the development of most leaf miner larvae is restricted to a single leaf . Second, leaf miners could make leaves fall year-round and return the nutrients back to the tree in a more even way (Owen, 1978).…”