Direct and indirect influences of intercrops on the coconut defoliator Opisina arenosella

Abstract

Coconut palm (Cocos nucifera) infestation by Opisina arenosella (Lepidoptera: Oecophoridae) in the Indian subcontinent may occur in November to May each year in the same or adjoining areas of plantations. Parasitoids of O. arenosella may also be consistently present at these times. During other periods, pests and/or parasitoids could be maintained on intercrops that are commonly grown throughout the year. Field surveys of 54 intercrop species in Kerala, India, found that O. arenosella attacks banana, but not others, while laboratory screening showed that O. arenosella can mature on jack fruit, cashew and oil palm. Larvae of 20 lepidopteran species found on intercrops were screened for use by Goniozus nephantidis (Hymenoptera: Bethylidae), a larval parasitoid of O. arenosella, which oviposited on two species but its offspring failed to mature. Thirteen intercrop herbivore species were screened for use by Brachymeria nosatoi (Hymenoptera: Chalcididae), a pupal parasitoid of O. arenosella, which completed development on the pyralids Herculia nigrivita, Syllepte derogata and Psara basalis. Further, connectance trophic webs were compiled using prior field records of coconut, 33 species of intercrops, 58 species of lepidopteran herbivores and 29 species of primary parasitoids. Both laboratory and literature evidence suggests that populations of O. arenosella are unlikely to be maintained by feeding on intercrops or strongly influenced by direct competition with other lepidopterans but are likely to be affected by sharing parasitoids. Intercrop herbivores have clear potential for maintaining parasitoids of O. arenosella, and we recommend thirteen plant species as intercrops that should aid in conservation biocontrol.

Goniozus omanensis (Hymenoptera: Bethylidae) an important parasitoid of the lesser date moth Batrachedra amydraula Meyrick (Lepidoptera: Batrachedridae) in Oman

“…omanensi s appears to be the numerically dominant parasitoid in Omani date palm plantations, its population biology may be influenced by behavioural and ecological interactions with other natural enemies of B . amydraula (as in other agro-ecosystems; [45,46]. We note in particular that there is no information on whether the geographical range of G .…”

Contests between beneficial natural enemies: brood‐guarding parasitoids vs. foraging predators

“…The black headed caterpillar, Opisina arenosella (Walker) (Lepidoptera: Oecophoridae), is an important pest that feeds on the leaves of coconut palm, Cocos nucifera (L.) (Arecaceae), making galleries of silk and frass on the leaf under‐surface and causing severe yield loss. The most important infestations occur in November to May each year (Sreekanth & Muralimohan, 2013; Shameer et al, 2018). Attempts to control O. arenosella have been made by applying chemical pesticides, via stem injection or via spraying, but this has had adverse non‐target effects.…”

“…One of the principal parasitoids of O. arenosella is Goniozus nephantidis (Muesebeck) (Hymenoptera: Bethylidae) (Cock & Perera, 1987; Sujatha & Singh, 1999; Sreenivas & Hardy, 2016; Shameer et al, 2018). Adult females enter the galleries constructed by feeding O. arenosella larvae and paralyze them by stinging.…”

Complete mitochondrial genome of the coconut black-headed caterpillar Opisina arenosella (Lepidoptera: Gelechioidea: Xyloryctidae)

“…The coconut black-headed caterpillar Opisina arenosella Walker is one of the major coconut leaf-feeding pests with outbreaks causing serious damage to coconut and other palms in India and Sri Lanka and it has been widely distributed in Myanmar, Pakistan, Thailand, Bangladesh, Malaysia, and Indonesia (Kumara et al 2015;Shameer et al 2018). Recently, it has invaded Hainan Province and Guangxi Zhuang Autonomous Region in China (Li et al 2014).…”

“…Recently, it has invaded Hainan Province and Guangxi Zhuang Autonomous Region in China (Li et al 2014). To date, studies of O. arenosella have mainly focused on its biological characteristics (Muralimohan and Srinivasa 2008;Kumara et al 2015), biological control (Venkatesan et al 2009;Shameer et al 2018), etc. Few studies have been devoted to the molecular characterization of O. arenosella.…”