Leafroller oviposition on larval host plants

Abstract

Caged greenheaded leafroller (Planotortrix excessana (Walker)) (Lepidoptera: Tortricidae) and lightbrown apple moth (Epiphyaspostvittana (Walker)) (Lepidoptera: Tortricidae) adults were provided with the leaves of known larval host plants to determine the relative amount of oviposition on the different hosts. Relative to apple leaves, lightbrown apple moth oviposited fewer eggs on narrow-leaved plantain (Plantago lanceolata L.), and blackberry (Rubus st~igolosus agg.) and equal numbers on poplar (Populus nigra L.). Greenheaded leafrollers laid more eggs on poplar leaves than on apple leaves. Close examination of the likely factors determining oviposition sites revealed that hairs on the dorsal leaf surface could affect the choice of oviposition sites.Lightbrown apple moths therefore tended to oviposit more frequently on the less hairy mature leaves of apple shoots compared to more hairy, emerging leaves which had a greater density of dorsal surface leaf hairs. Arrangement of host plant leaf clusters may have affected oviposition site preference as lightbrown apple moths tended to lay relatively more eggs on apple fruiting clusters than shoots.

The effects of mating, age at mating, and plant stimuli, on the lifetime fecundity and fertility of the generalist herbivore Epiphyas postvittana

“…That fecundity decreased as leaf pubescence increased, is consistent with texture strongly influencing host selection by female E. postvittana (Danthanarayana, 1975;Tomkins et al, 1991;Foster et al, 1997;Foster & Howard, 1998). Further supporting this are the no-choice experiments with plants of different acceptability, in which there were substantial differences in fecundity on the three plants.…”

“…The larvae of this pest are highly polyphagous, with more than 250 species in more than 50 families of plants recorded as hosts (Wearing et al, 1991). ), and are influenced by non-specific plant stimuli, including texture, with females preferring to lay on smooth surfaces (Danthanarayana, 1975;Foster et al, 1997) with varicose texture (Foster & Howard, 1998), rather than rough surfaces (Tomkins et al, 1991;Foster et al, 1997), long chain alkanes (Foster and Howard, unpubl. The polyphagy of the larvae is matched by the ovipositional specificity of the females.…”

Bioassays for measuring ovipositional and larval preferences of leafrollers (Lepidoptera: Tortricidae) for different cultivars of apple

“…The strong preference for egg laying on the upper leaf surface in these experiments was similar to that reported in the field by Green (1984) and Tomkins et al (1991), and in the laboratory by Foster et al (1997). The wide variation in the vertical distribution of egg batches on the terminals in the oviposition bioassay suggests that all the expanded leaves were equally suitable for egg laying.…”

Oviposition preference and larval performance of Epiphyas postvittana (Lepidoptera: Tortricidae) on Botrytis cinerea (Helotiales: Sclerotiniaceae) infected berries of Vitis vinifera (Vitales: Vitaceae)

“…Surface texture plays a role in the oviposition behavior of gravid E. postvittana , which prefers to lay eggs on smooth surfaces of varicose texture, rather than on rough and hairy surfaces such as the abaxial sides of the leaves of V. vinifera (Rizvi et al ., ). This corroborates with the pattern of oviposition in E. postvittana noted in natural environments on the leaves of V. vinifera (Danthanarayana, ) and Malus domestica (Rosaceae) (Tomkins et al ., ). The fungal mycelia growing on the surfaces of either leaves or berries of V. vinifera mimic hairiness, and possibly that acts as a physical barrier in the preference of E. postvittana during oviposition (Rizvi et al ., ).…”