Hawkmoth Behaviour and Flower Adaptation Reducing Self Pollination in Two Liliiflorae

Abstract

Summary In experiments with models and a Petunia cultivar a hawkmoth makes its initial approach at about the same level as the flower. In Lilium martagon L., after flower opening, the style curves towards the direction of maximum light intensity. A hawkmoth comes into contact with the stigma at the beginning of its visit. Thereafter, while drinking from the individual nectaries on each petal, the visitor picks up pollen from the anther in front of the petals. During the initial approach to Crinum jagns (Thomp.). Dandy flowers a hawkmoth touches only the stigma, which is in front of the anthers. Anthers contact the visitor's body only during drinking. Then the moth leaves the flower by flying upwards and does not touch the stigma again. Thus there is evidence that in two Lilüflorae, the combination of the moth‐behaviour with the flower structure might reduce self‐pollination.

Flight behaviour of the hawkmothManduca sextatowards unimodal and multimodal targets

“…The lack of this counterturning in the flight paths recorded in the present study is most likely due to the lack of a uniform airflow in our arena, where, instead, the local concentration gradients and the plume fragments provide information about the location of the odour source (Fraenkel and Gunn, 1961). Straight flight in moths has also been reported previously from flight conditions with homogeneous or turbulent odour plumes (Mafra-Neto and Cardé, 1994), as well as in still air (Brantjes, 1978;Brantjes and Bos, 1980). When approaching the multimodal target -which was both clearly visible and carried an odour -the moths turned directly towards it (Fig.5) and were also able to locate it from any visual angle (Fig.7).…”

The role of mechanosensory input in flower handling efficiency and learning byManduca sexta

“…Further investigation of the influence of mechanoreception on probing behavior led to Experiment 2, in which we found that corolla grooves positively affect the handling performance when they converge at the nectary and negatively affect it when they are incorrectly oriented (Fig.·5). This suggests that three-dimensional features have a hierarchical precedence on nectar-searching behavior at the flower handling scale as proposed by Brantjes and Bos (Brantjes and Bos, 1980). At this level, the spatial resolution of M. sexta's eyes does not allow for accurate feedback about proboscis position (A.…”

The avoidance of interference between the presentation of pollen and stigmas in angiosperms II. Herkogamy

“…1E), Polemoniaceae (Grant & Grant 1965), and others. Brantjes & Bos (1980) provided three detailed examples of what we describe as approach herkogamy, all in species pollinated by hawkmoths:…”