Sensory biology of Chilo spp. with specific reference to C. partellus

Abstract

This paper reports observations made on the sensory biology of Chilo partellus larvae and adults. The larval and adult antennae of this insect have hygro/thermosensitive sensilla equipped with receptor cells sensitive to minute changes in temperature. Inputs through those cells may partly be responsible for the light evasive and other light/temperaturedependent behaviour patterns. The grooved basiconic sensilla especially those found on the male antennae are sensitive to the female sex pheromone components of C. partellus. Hostplant odours are most likely perceived by one or two of the other antennal olfactory sensilla, namely the smooth-surfaced basiconica and coeloconica sensilla. Chilo partellus moths have a limited number of gustatory sensilla on the tarsi, ovipositor, antennae and the proboscis. Electrophysiological bioassays done on the ovipositor and tarsal sensilla are discussed. Similar tests on the larval maxillary styloconica sensilla showed that the lateral and medial sensilla differed in their sensitivity. Their taste receptor cells can detect differences between saps from susceptible and resistant host-plants. Resume-Cette publication est basee sur certaines observations faites sur la biologie sensorielle des larves et adultes de Chilo partellus. Les antennes de larves et adultes de Chilo partellus ont des sensilles hygro-thermosensibles equipees de cellules receptrices qui enregistrent les changements dues a la temperature. L'energie provenant de ces cellules peuvent partiellement etre responsable du pheromene evasif a la lumiere et autres facteurs dependant de lumiere-temperature. Les sensilles basiconiques specialement ceux qu'on trouve sur les antennes des males sont sensible a 1'effet des pheromones sexuels de Chilo partellus. Les odeurs des plantes-hotes sont apercues soit par un ou deux types de sensilles olfactrices de l'antenne appelees sensilles basiconiques ayant une surface lisse et les sensilles coeloconiques. Les adultes de C. partellus ont un nombre limite de sensilles gustatrices sur les tarses, les bvipositeurs, les antennes et le proboscis. Les donnees electrophysiologiques des essais biologiques faits sur les sensilles des tarses et de l'ovipositeur ont ete discutles. Des epreuves similaires faites sur les sensilles styloconiques des larves ont montre que les sensilles laterales et medianes different de leur sensibilite et que les cellules receptrices peuvent detecter les differences entre les plantes-hdtes resistantes et susceptibles.

Comparison of Sensory Structures Present on Larval Antennae and Mouthparts of Lepidopteran Crop Pests

“…The structures of the sensilla chaetica, sensilla styloconica, and sensilla basiconica have been established. The external morphology, distribution, and types of sensilla on antennae and mouthparts in the 4 species we studied largely agree with those reported for other lepidopteran species (Sanes & Hildebrand 1976;Baker et al 1986;Waladde & Kahoro 1990;Koh et al 1995;Keil 1996;Lin 1997;Malo et al 2004;Li et al 2008;Wang et al 2008;Dey et al 2011;Barsagade et al 2013;Zhao et al 2013;Zheng et al 2014).…”

“…Other reports of sensory structures in lepidopterans document the distribution, morphology, and number of sensory receptors on the larval maxillae and labia of Heliothis virescens (F.) and Helicoverpa zea Boddie (Noctuidae) (Baker et al 1986); the type and distribution of antennal sensilla in Manduca sexta L. (Sphingidae) (Sanes & Hildebrand 1976), C. partellus (Waladde & Kahoro 1990), Helicoverpa assulta Guenée (Noctuidae) (Koh et al 1995), Spodoptera frugiperda (J. E. Smith) (Noctuidae ) (Malo et al 2004), Maruca testulalis (Geyer) (Pyralidae) (Wang et al 2008), and Catocala remissa Staudinger (Noctuidae) (Zheng et al 2014); and the sensory structures present on the maxillary and labial palps of Helicoverpa armigera (Hübner) (Noctuidae), which are responsible for chemoreception (Keil 1996;Zhao et al 2013).…”

“…In many lepidopteran larvae, the chemosensilla or chemoreceptors present on galea, maxillary palp, and the inner surface of the labrum are involved in determining food preferences (Ishikawa 1963;Ma 1972;Dethier 1973;Stadler & Hanson 1975;De Boer et al 1977;Albert 1980;Devitt & Smith 1982;Wazalwar & Khurad 2009). In larvae of C. partellus, the antennae contain sensilla basiconica and sensilla coeloconica that have olfactory function, and the maxillary palp contains sensilla styloconica that detect the difference between saps from susceptible and resistant host plants (Waladde & Kahoro 1990). Li et al (2008) documented the morphology and distribution of sensilla present on larval antennae and mouthparts of Spodoptera exigua Hübner (Noctuidae).…”

Behaviour and biology ofChilo partelluson maize landraces

“…Volatile cues from host plants provide crucial information for many herbivores during orientation towards a plant (Bruce & Pickett, ). In addition to chemical cues, physical plant characteristics also play a role in assessment of host‐plant suitability (Waladde et al., ). The HIPVs produced as a result of herbivore attack have been shown to reduce further herbivore colonisation by affecting the host selection behaviour in herbivores or attracting natural enemies of herbivores (Karban, ; Zakir et al., ).…”

Evaluation of Napier grass (Pennisetum purpureum) varieties for use as trap plants for the management of African stemborer (Busseola fusca) in a push–pull strategy

“…A majority of these insects are, therefore, able to discriminate between plants that are acceptable for oviposition and feeding and those that are not (Otter & Kahoro, 1983; Rebe et al., 2004). Host‐plant colonization by cereal stemborers, which are the most injurious insects of maize and sorghum in sub‐Saharan Africa (Kfir et al., 2002), is a process based on the interactions between sensory cells and the physical and chemical characteristics of the plant (Waladde et al., 1990).…”